1
|
Dahir KM, Rush ET, Diaz-Mendoza S, Kishnani PS. A Delphi panel to build consensus on assessing disease severity and disease progression in adult patients with hypophosphatasia in the United States. J Endocrinol Invest 2024; 47:1487-1497. [PMID: 38236379 DOI: 10.1007/s40618-023-02256-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Accepted: 11/21/2023] [Indexed: 01/19/2024]
Abstract
BACKGROUND Hypophosphatasia (HPP) is an inborn error of metabolism with a variable presentation. We conducted a modified Delphi panel to obtain expert consensus on knowledge gaps regarding disease severity and progression in adult patients with HPP. METHODS Healthcare professionals (HCPs) with experience managing adult patients with HPP were recruited to participate in a 3-round Delphi panel (round 1: paper survey and 1:1 interview; rounds 2-3: email survey). Panelists rated the extent of their agreement with statements about disease severity and progression in adult patients with HPP. Consensus was defined as ≥ 80% agreement. RESULTS Ten HCPs completed round 1; nine completed rounds 2 and 3. Consensus was reached on 46/120 statements derived from steering committee input. Disease severity markers in adult patients with HPP can be bone-related (recurrent/poorly healing fractures, pseudo-fractures, metatarsal fractures, osteomalacia) or involve dentition or physiologic/functional manifestations (use of mobility devices/home modifications, abnormal gait, pain). Disease progression markers can include recurrent/poorly healing low-trauma fractures, development of ectopic calcifications, and/or impairment of functional activity. Panelists supported the development of a tool to help assess disease severity in the clinic and track changes in severity over time. Panelists also highlighted the role of a multidisciplinary team, centers with expertise, and the need to refer patients when disease severity is not clear. CONCLUSIONS These statements regarding disease severity, progression, and assessment methods address some knowledge gaps in adult patients with HPP and may be helpful for treating HCPs, although the small sample size affects the ability to generalize the healthcare provider experience.
Collapse
Affiliation(s)
- K M Dahir
- Division of Endocrinology and Metabolism, Vanderbilt University Medical Center, 1215 21st Ave S Suite 8210, Nashville, TN, 37232, USA.
| | - E T Rush
- Division of Clinical Genetics, Children's Mercy Kansas City, 2401 Gillham Rd, Kansas City, MO, 64108, USA.
- Department of Pediatrics, University of Missouri-Kansas City School of Medicine, Kansas City, MO, USA.
- Department of Internal Medicine, University of Kansas School of Medicine, Kansas City, KS, USA.
| | | | - P S Kishnani
- Division of Medical Genetics, Department of Pediatrics, Duke University School of Medicine, Durham, NC, USA
| |
Collapse
|
2
|
Larid G, Vix J, Preuss P, Robin F, Tison A, Delaveau C, Krajewski F, Bouvard B, Chu Miow Lin D, Guggenbuhl P, Maugars Y, Saraux A, Debiais F. Detection of hypophosphatasia in hospitalised adults in rheumatology and internal medicine departments: a multicentre study over 10 years. RMD Open 2024; 10:e004316. [PMID: 38580346 PMCID: PMC11002352 DOI: 10.1136/rmdopen-2024-004316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2024] [Accepted: 03/15/2024] [Indexed: 04/07/2024] Open
Abstract
INTRODUCTION Hypophosphatasia (HPP) is a rare genetic disease caused by loss-of-function mutations in the ALPL gene encoding the tissue non-specific alkaline phosphatase (ALP). Mild HPP is usually misdiagnosed in adult age. While an elevated serum ALP value draws more attention than a low value, low serum ALP should be better recognised and may lead to HPP detection. METHODS Patients were selected from the records of the biochemistry department of six University Hospitals in France. Patients were hospitalised in the departments of rheumatology and internal medicine between 2007 and 2017. RESULTS 56 321 hospitalised patients had at least 2 serum ALP dosages and 664 of these patients had at least 2 low serum ALP≤35 UI/L. Among these 664 patients, 482 (72.6%) had fluctuating low values (mean age 62.9 years; 60% of women) and 182 patients (27.4%) had persistent low values below 35 IU/L (mean age 53.4 years; 67% of women). Among patients with persistent hypophosphatasaemia treated with bisphosphonates, 70.8% never had ALP measurement before treatment and 20.8% were treated despite an abnormal decrease of ALP. Genetic testing was performed in 18 patients and was positive in 11. Genetic diagnosis of HPP was at least 6.0% in persistent hypophosphatasaemia and at least 15.9% in patients with at least three symptoms suggestive of HPP. CONCLUSION In this 10-year retrospective study, 0.32% of adult patients hospitalised in the rheumatology and internal medicine departments had persistently low serum ALP, and among them, 6% had genetically proven HPP. Reported hypophosphatasaemia represented only 3.6% of hospitalised patients.
Collapse
Affiliation(s)
- Guillaume Larid
- Department of Rheumatology, CHU Poitiers, Poitiers, France
- LITEC, Poitiers University, Poitiers, France
| | - Justine Vix
- Department of Rheumatology, CHU Poitiers, Poitiers, France
| | | | | | | | | | | | | | - Delphine Chu Miow Lin
- Department of Rheumatology, CHU de Tours, Tours, France
- Université de Tours, Tours, France
| | | | | | | | | |
Collapse
|
3
|
Khan AA, Brandi ML, Rush ET, Ali DS, Al-Alwani H, Almonaei K, Alsarraf F, Bacrot S, Dahir KM, Dandurand K, Deal C, Ferrari SL, Giusti F, Guyatt G, Hatcher E, Ing SW, Javaid MK, Khan S, Kocijan R, Linglart A, M'Hiri I, Marini F, Nunes ME, Rockman-Greenberg C, Roux C, Seefried L, Simmons JH, Starling SR, Ward LM, Yao L, Brignardello-Petersen R, Lewiecki EM. Hypophosphatasia diagnosis: current state of the art and proposed diagnostic criteria for children and adults. Osteoporos Int 2024; 35:431-438. [PMID: 37982857 PMCID: PMC10866785 DOI: 10.1007/s00198-023-06844-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Accepted: 06/23/2023] [Indexed: 11/21/2023]
Abstract
BACKGROUND This manuscript provides a summary of the current evidence to support the criteria for diagnosing a child or adult with hypophosphatasia (HPP). The diagnosis of HPP is made on the basis of integrating clinical features, laboratory profile, radiographic features of the condition, and DNA analysis identifying the presence of a pathogenic variant of the tissue nonspecific alkaline phosphatase gene (ALPL). Often, the diagnosis of HPP is significantly delayed in both adults and children, and updated diagnostic criteria are required to keep pace with our evolving understanding regarding the relationship between ALPL genotype and associated HPP clinical features. METHODS An International Working Group (IWG) on HPP was formed, comprised of a multidisciplinary team of experts from Europe and North America with expertise in the diagnosis and management of patients with HPP. Methodologists (Romina Brignardello-Petersen and Gordon Guyatt) and their team supported the IWG and conducted systematic reviews following the GRADE methodology, and this provided the basis for the recommendations. RESULTS The IWG completed systematic reviews of the literature, including case reports and expert opinion papers describing the phenotype of patients with HPP. The published data are largely retrospective and include a relatively small number of patients with this rare condition. It is anticipated that further knowledge will lead to improvement in the quality of genotype-phenotype reporting in this condition. CONCLUSION Following consensus meetings, agreement was reached regarding the major and minor criteria that can assist in establishing a clinical diagnosis of HPP in adults and children.
Collapse
Affiliation(s)
- Aliya A Khan
- Division of Endocrinology and Metabolism, McMaster University, Hamilton, Canada.
| | - Maria Luisa Brandi
- F.I.R.M.O. Italian Foundation for the Research On Bone Diseases, Florence, Italy
- Donatello Bone Clinic, Villa Donatello Hospital, Florence, Italy
| | - Eric T Rush
- Division of Clinical Genetics, Children's Mercy Kansas City, Kansas City, MO, USA
- Division of Endocrinology, Metabolism, Osteoporosis and Genetics, Department of Internal Medicine, University of Kansas School of Medicine, Kansas City, KS, USA
- Department of Pediatrics, University of Missouri-Kansas City School of Medicine, Kansas City, MO, USA
| | - Dalal S Ali
- Division of Endocrinology and Metabolism, McMaster University, Hamilton, Canada
| | - Hatim Al-Alwani
- Division of Endocrinology and Metabolism, McMaster University, Hamilton, Canada
| | - Khulod Almonaei
- Division of Endocrinology and Metabolism, McMaster University, Hamilton, Canada
| | - Farah Alsarraf
- Division of Endocrinology and Metabolism, McMaster University, Hamilton, Canada
| | - Severine Bacrot
- Department of Genetics, Centre Hospitalier de Versailles, Hôpital André Mignot, Versailles, France
| | - Kathryn M Dahir
- Division of Endocrinology and Metabolism, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Karel Dandurand
- Department of Medicine, Endocrinology and Metabolism, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Chad Deal
- Center for Osteoporosis and Metabolic Bone Disease, Department of Rheumatology, The Cleveland Clinic Foundation, Cleveland, OH, USA
| | - Serge Livio Ferrari
- Division of Bone Diseases, Department of Internal Medicine Specialties, Geneva University Hospitals and Faculty of Medicine, Geneva, Switzerland
| | - Francesca Giusti
- Donatello Bone Clinic, Villa Donatello Hospital, Florence, Italy
| | - Gordon Guyatt
- Department of Health Research Methods, Evidence and Impact at McMaster University, Hamilton, Canada
| | - Erin Hatcher
- Neuromuscular Clinic, McMaster University Medical Centre, Hamilton Health Sciences, Hamilton, Canada
| | - Steven W Ing
- Division of Endocrinology, Diabetes & Metabolism, Ohio State University Wexner Medical Center, Columbus, OH, USA
| | - Muhammad Kassim Javaid
- Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, University of Oxford, Oxford, UK
| | - Sarah Khan
- Bone Research and Education Centre, Oakville, ON, Canada
| | - Roland Kocijan
- Ludwig Boltzmann Institute of Osteology at Hanusch Hospital of OEGK and AUVA, Trauma Centre Meidling, 1St Medical Department Hanusch Hospital, 1140, Vienna, Austria
| | - Agnes Linglart
- APHP, Bicêtre Paris-Sud, UniversityParis Sud, Paris-Saclay, Le Kremlin Bicêtre, Paris, France
| | - Iman M'Hiri
- Bone Research and Education Centre, Oakville, ON, Canada
| | - Francesca Marini
- F.I.R.M.O. Italian Foundation for the Research On Bone Diseases, Florence, Italy
| | - Mark E Nunes
- Division of Medical Genetics and Metabolism, Valley Children's HealthCare, Madera, CA, USA
| | | | - Christian Roux
- INSERM CRESS UMR 1153, Paris, France
- Université Paris-Cité, Department of Rheumatology, APHP-Centre, Cochin Hospital, Paris, France
| | - Lothar Seefried
- Musculoskeletal Center Wuerzburg, University of Würzburg, Würzburg, Germany
| | - Jill H Simmons
- Division of Endocrinology and Metabolism, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Susan R Starling
- Division of Clinical Genetics, Children's Mercy Kansas City, Kansas City, MO, USA
| | - Leanne M Ward
- Children's Hospital of Eastern Ontario, Department of Pediatrics, University of Ottawa, Ottawa, ON, Canada
| | - Liang Yao
- Department of Health Research Methods, Evidence and Impact at McMaster University, Hamilton, Canada
| | | | - E Michael Lewiecki
- New Mexico Clinical Research & Osteoporosis Center, Albuquerque, NM, USA
| |
Collapse
|
4
|
González-Cejudo T, Villa-Suárez JM, Ferrer-Millán M, Andújar-Vera F, Contreras-Bolívar V, Andreo-López MC, Gómez-Vida JM, Martínez-Heredia L, González-Salvatierra S, de Haro Muñoz T, García-Fontana C, Muñoz-Torres M, García-Fontana B. Mild hypophosphatasia may be twice as prevalent as previously estimated: an effective clinical algorithm to detect undiagnosed cases. Clin Chem Lab Med 2024; 62:128-137. [PMID: 37440753 DOI: 10.1515/cclm-2023-0427] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Accepted: 07/04/2023] [Indexed: 07/15/2023]
Abstract
OBJECTIVES Since the prevalence of hypophosphatasia (HPP), a rare genetic disease, seems to be underestimated in clinical practice, in this study, a new diagnostic algorithm to identify missed cases of HPP was developed and implemented. METHODS Analytical determinations recorded in the Clinical Analysis Unit of the Hospital Universitario Clínico San Cecilio in the period June 2018 - December 2020 were reviewed. A new clinical algorithm to detect HPP-misdiagnosed cases was used including the following steps: confirmation of persistent hypophosphatasemia, exclusion of secondary causes of hypophosphatasemia, determination of serum pyridoxal-5'-phosphate (PLP) and genetic study of ALPL gene. RESULTS Twenty-four subjects were selected to participate in the study and genetic testing was carried out in 20 of them following clinical algorithm criteria. Eighty percent of patients was misdiagnosed with HPP following the current standard clinical practice. Extrapolating these results to the current Spanish population means that there could be up to 27,177 cases of undiagnosed HPP in Spain. In addition, we found a substantial proportion of HPP patients affected by other comorbidities, such as autoimmune diseases (∼40 %). CONCLUSIONS This new algorithm was effective in detecting previously undiagnosed cases of HPP, which appears to be twice as prevalent as previously estimated for the European population. In the near future, our algorithm could be globally applied routinely in clinical practice to minimize the underdiagnosis of HPP. Additionally, some relevant findings, such as the high prevalence of autoimmune diseases in HPP-affected patients, should be investigated to better characterize this disorder.
Collapse
Affiliation(s)
- Trinidad González-Cejudo
- Clinical Analysis Unit, University Hospital Clínico San Cecilio, Granada, Spain
- Department of Medicine, University of Granada, Granada, Spain
| | | | - María Ferrer-Millán
- Instituto de Investigación Biosanitaria de Granada (ibs. GRANADA), Granada, Spain
| | - Francisco Andújar-Vera
- Department of Computer Science and Artificial Intelligence, University of Granada, Granada, Spain
- CIBER on Frailty and Healthy Aging (CIBERFES), Instituto de Salud Carlos III, Madrid, Spain
- Andalusian Research Institute in Data Science and Computational Intelligence (DaSCI Institute), Granada, Spain
| | - Victoria Contreras-Bolívar
- Instituto de Investigación Biosanitaria de Granada (ibs. GRANADA), Granada, Spain
- Endocrinology and Nutrition Unit, University Hospital Clínico San Cecilio, Granada, Spain
| | | | | | | | - Sheila González-Salvatierra
- Instituto de Investigación Biosanitaria de Granada (ibs. GRANADA), Granada, Spain
- Department of Biochemistry and Molecular Biology II, Faculty of Pharmacy, University of Granada, Granada, Spain
| | - Tomás de Haro Muñoz
- Clinical Analysis Unit, University Hospital Clínico San Cecilio, Granada, Spain
| | - Cristina García-Fontana
- Instituto de Investigación Biosanitaria de Granada (ibs. GRANADA), Granada, Spain
- CIBER on Frailty and Healthy Aging (CIBERFES), Instituto de Salud Carlos III, Madrid, Spain
- Endocrinology and Nutrition Unit, University Hospital Clínico San Cecilio, Granada, Spain
| | - Manuel Muñoz-Torres
- Department of Medicine, University of Granada, Granada, Spain
- Instituto de Investigación Biosanitaria de Granada (ibs. GRANADA), Granada, Spain
- CIBER on Frailty and Healthy Aging (CIBERFES), Instituto de Salud Carlos III, Madrid, Spain
- Endocrinology and Nutrition Unit, University Hospital Clínico San Cecilio, Granada, Spain
| | - Beatriz García-Fontana
- Instituto de Investigación Biosanitaria de Granada (ibs. GRANADA), Granada, Spain
- CIBER on Frailty and Healthy Aging (CIBERFES), Instituto de Salud Carlos III, Madrid, Spain
- Department of Cell Biology, University of Granada, Granada, Spain
| |
Collapse
|
5
|
Kim SM, Korkmaz F, Sims S, Ryu V, Yuen T, Zaidi M. Musculoskeletal and neurocognitive clinical significance of adult hypophosphatasia. Osteoporos Sarcopenia 2023; 9:115-120. [PMID: 38374822 PMCID: PMC10874721 DOI: 10.1016/j.afos.2023.12.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2023] [Revised: 12/03/2023] [Accepted: 12/12/2023] [Indexed: 02/21/2024] Open
Abstract
Hypophosphatasia (HPP), also called Rathbun disease, is a rare genetic disorder that is caused by the loss-of-function mutation in the ALPL gene encoding tissue non-specific alkaline phosphatase. Doctor Rathbun first described the case of a 3-week-old infant who presented with severe osteopenia, rickets, and multiple radiographic fractures, and died shortly after of epileptic seizure and respiratory distress. The term "hypophosphatasia" was coined as the patients' alkaline phosphatase levels were significantly low. Since then, our understanding of HPP has evolved, and now we appreciate causative genetic mutation and the broad spectrum of clinical presentation depending on the age of onset, severity, and skeletal involvement: perinatal, infantile, childhood, adult and odontohypophosphatasia. The new development of enzyme replacement with asfostase alfa has saved the lives of severe form of hypophosphatasia. However, it is still unclear and remains challenging how to manage adult HPP that often presents with mild and non-specific symptoms such as muscle pain, joint stiffness, fatigue, anxiety, or low bone mass, which are common in the general population and not necessarily attributed to HPP. In this review, we will present 3 unique cases of adult HPP and discuss the pathophysiology, clinical presentation particularly neuromuscular and neurocognitive symptoms and management of adult HPP.
Collapse
Affiliation(s)
- Se-Min Kim
- Center for Translational Medicine and Pharmacological Science, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Funda Korkmaz
- Center for Translational Medicine and Pharmacological Science, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Steve Sims
- Center for Translational Medicine and Pharmacological Science, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Vitaly Ryu
- Center for Translational Medicine and Pharmacological Science, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Tony Yuen
- Center for Translational Medicine and Pharmacological Science, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Mone Zaidi
- Center for Translational Medicine and Pharmacological Science, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| |
Collapse
|
6
|
Li X, Ren N, Wang Z, Wang Y, Hu Y, Hu W, Gu J, Hong W, Zhang Z, Wang C. Clinical and Genetic Characteristics of Hypophosphatasia in Chinese Adults. Genes (Basel) 2023; 14:genes14040922. [PMID: 37107680 PMCID: PMC10137706 DOI: 10.3390/genes14040922] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 04/06/2023] [Accepted: 04/12/2023] [Indexed: 04/29/2023] Open
Abstract
Hypophosphatasia (HPP) is an inherited disease caused by ALPL mutation, resulting in decreased alkaline phosphatase (ALP) activity and damage to bone and tooth mineralization. The clinical symptoms of adult HPP are variable, making diagnosis challenging. This study aims to clarify the clinical and genetic characteristics of HPP in Chinese adults. There were 19 patients, including 1 with childhood-onset and 18 with adult-onset HPP. The median age was 62 (32-74) years and 16 female patients were involved. Common symptoms included musculoskeletal symptoms (12/19), dental problems (8/19), fractures (7/19), and fatigue (6/19). Nine patients (47.4%) were misdiagnosed with osteoporosis and six received anti-resorptive treatment. The average serum ALP level was 29.1 (14-53) U/L and 94.7% (18/19) of patients had ALP levels below 40 U/L. Genetic analysis found 14 ALPL mutations, including three novel mutations-c.511C>G (p.His171Ala), c.782C>A (p.Pro261Gln), and 1399A>G (p.Met467Val). The symptoms of two patients with compound heterozygous mutations were more severe than those with heterozygous mutations. Our study summarized the clinical characteristics of adult HPP patients in the Chinese population, expanded the spectrum of pathogenic mutations, and deepened clinicians' understanding of this neglected disease.
Collapse
Affiliation(s)
- Xiang Li
- Shanghai Clinical Research Center of Bone Disease & Department of Osteoporosis and Bone Diseases, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200233, China
| | - Na Ren
- Shanghai Clinical Research Center of Bone Disease & Department of Osteoporosis and Bone Diseases, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200233, China
| | - Ziyuan Wang
- Shanghai Clinical Research Center of Bone Disease & Department of Osteoporosis and Bone Diseases, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200233, China
| | - Ya Wang
- Shanghai Clinical Research Center of Bone Disease & Department of Osteoporosis and Bone Diseases, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200233, China
| | - Yunqiu Hu
- Shanghai Clinical Research Center of Bone Disease & Department of Osteoporosis and Bone Diseases, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200233, China
| | - Weiwei Hu
- Shanghai Clinical Research Center of Bone Disease & Department of Osteoporosis and Bone Diseases, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200233, China
| | - Jiemei Gu
- Shanghai Clinical Research Center of Bone Disease & Department of Osteoporosis and Bone Diseases, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200233, China
| | - Wei Hong
- Department of Osteoporosis & Shanghai Key Laboratory of Clinical Geriatric Medicine, Huadong Hospital, Fudan University, Shanghai 200040, China
| | - Zhenlin Zhang
- Clinical Research Center, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200233, China
| | - Chun Wang
- Shanghai Clinical Research Center of Bone Disease & Department of Osteoporosis and Bone Diseases, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai 200233, China
| |
Collapse
|
7
|
Dicks AR, Maksaev GI, Harissa Z, Savadipour A, Tang R, Steward N, Liedtke W, Nichols CG, Wu CL, Guilak F. Skeletal dysplasia-causing TRPV4 mutations suppress the hypertrophic differentiation of human iPSC-derived chondrocytes. eLife 2023; 12:e71154. [PMID: 36810131 PMCID: PMC9949800 DOI: 10.7554/elife.71154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Accepted: 02/03/2023] [Indexed: 02/24/2023] Open
Abstract
Mutations in the TRPV4 ion channel can lead to a range of skeletal dysplasias. However, the mechanisms by which TRPV4 mutations lead to distinct disease severity remain unknown. Here, we use CRISPR-Cas9-edited human-induced pluripotent stem cells (hiPSCs) harboring either the mild V620I or lethal T89I mutations to elucidate the differential effects on channel function and chondrogenic differentiation. We found that hiPSC-derived chondrocytes with the V620I mutation exhibited increased basal currents through TRPV4. However, both mutations showed more rapid calcium signaling with a reduced overall magnitude in response to TRPV4 agonist GSK1016790A compared to wildtype (WT). There were no differences in overall cartilaginous matrix production, but the V620I mutation resulted in reduced mechanical properties of cartilage matrix later in chondrogenesis. mRNA sequencing revealed that both mutations up-regulated several anterior HOX genes and down-regulated antioxidant genes CAT and GSTA1 throughout chondrogenesis. BMP4 treatment up-regulated several essential hypertrophic genes in WT chondrocytes; however, this hypertrophic maturation response was inhibited in mutant chondrocytes. These results indicate that the TRPV4 mutations alter BMP signaling in chondrocytes and prevent proper chondrocyte hypertrophy, as a potential mechanism for dysfunctional skeletal development. Our findings provide potential therapeutic targets for developing treatments for TRPV4-mediated skeletal dysplasias.
Collapse
Affiliation(s)
- Amanda R Dicks
- Department of Biomedical Engineering, Washington University in St. LouisSt LouisUnited States
- Department of Orthopedic Surgery, Washington University School of Medicine, St. LouisSt LouisUnited States
- Shriners Hospitals for Children - St. LouisSt. LouisUnited States
| | - Grigory I Maksaev
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. LouisSt LouisUnited States
| | - Zainab Harissa
- Department of Biomedical Engineering, Washington University in St. LouisSt LouisUnited States
- Department of Orthopedic Surgery, Washington University School of Medicine, St. LouisSt LouisUnited States
- Shriners Hospitals for Children - St. LouisSt. LouisUnited States
| | - Alireza Savadipour
- Department of Orthopedic Surgery, Washington University School of Medicine, St. LouisSt LouisUnited States
- Shriners Hospitals for Children - St. LouisSt. LouisUnited States
- Department of Mechanical Engineering and Material Science, Washington University in St. LouisSt. LouisUnited States
| | - Ruhang Tang
- Department of Orthopedic Surgery, Washington University School of Medicine, St. LouisSt LouisUnited States
- Shriners Hospitals for Children - St. LouisSt. LouisUnited States
| | - Nancy Steward
- Department of Orthopedic Surgery, Washington University School of Medicine, St. LouisSt LouisUnited States
- Shriners Hospitals for Children - St. LouisSt. LouisUnited States
| | - Wolfgang Liedtke
- Department of Neurology, Duke University School of MedicineDurhamUnited States
- Department of Molecular Pathobiology - NYU College of DentistryNew YorkUnited States
| | - Colin G Nichols
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. LouisSt LouisUnited States
| | - Chia-Lung Wu
- Department of Orthopaedics and Rehabilitation, Center for Musculoskeletal Research, University of RochesterRochesterUnited States
| | - Farshid Guilak
- Department of Orthopedic Surgery, Washington University School of Medicine, St. LouisSt LouisUnited States
- Shriners Hospitals for Children - St. LouisSt. LouisUnited States
| |
Collapse
|
8
|
Childhood Hypophosphatasia Associated with a Novel Biallelic ALPL Variant at the TNSALP Dimer Interface. Int J Mol Sci 2022; 24:ijms24010282. [PMID: 36613725 PMCID: PMC9820760 DOI: 10.3390/ijms24010282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Revised: 12/08/2022] [Accepted: 12/15/2022] [Indexed: 12/28/2022] Open
Abstract
The goal of this study was to perform a clinical and molecular investigation in an eight-year-old female child diagnosed with hypophosphatasia (HPP). The proband and her family were evaluated by medical and dental histories, biochemical analyses, radiographic imaging, and genetic analysis of the tissue-nonspecific alkaline phosphatase (ALPL) gene. A bioinformatic analysis was performed to predict the structural and functional impact of the point mutations in the tissue-nonspecific alkaline phosphatase (TNSALP) molecule and to define their potential contribution to the phenotype. We identified a novel combination of heterozygous ALPL missense variants in the proband, p.Ala33Val and p.Asn47His, compatible with an autosomal recessive mode of inheritance and resulting in skeletal and dental phenotypes. Computational modeling showed that the affected Asn47 residue is located in the coil structure close to the N-terminal α-helix, whereas the affected Ala33 residue is localized in the N-terminal α-helix. Both affected residues are located close to the homodimer interface, suggesting they may impair TNSALP dimer formation and stability. Clinical and biochemical follow-up revealed improvements after six years of ERT. Reporting this novel combination of ALPL variants in childhood HPP provides new insights into genotype-phenotype associations for HPP and specific sites within the TNSALP molecule potentially related to a childhood-onset HPP and skeletal and dental manifestations. Beneficial effects of ERT are implicated in skeletal and dental tissues.
Collapse
|
9
|
Zhu X, Gao Z, Wang Y, Huang W, Li Q, Jiao Z, Liu N, Kong X. Utility of trio-based prenatal exome sequencing incorporating splice-site and mitochondrial genome assessment in pregnancies with fetal ultrasound anomalies: prospective cohort study. ULTRASOUND IN OBSTETRICS & GYNECOLOGY : THE OFFICIAL JOURNAL OF THE INTERNATIONAL SOCIETY OF ULTRASOUND IN OBSTETRICS AND GYNECOLOGY 2022; 60:780-792. [PMID: 35726512 DOI: 10.1002/uog.24974] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2022] [Revised: 05/30/2022] [Accepted: 05/31/2022] [Indexed: 06/15/2023]
Abstract
OBJECTIVE To evaluate the utility of trio-based prenatal exome sequencing (pES), incorporating splice-site and mitochondrial genome assessment, in the prenatal diagnosis of fetuses with ultrasound anomalies and normal copy-number variant sequencing (CNV-seq) results. METHODS This was a prospective study of 90 ongoing pregnancies with ultrasound anomalies that underwent trio-based pES after receiving normal CNV-seq results, from September 2020 to November 2021, in a single center in China. By using pES with a panel encompassing exome coding and splicing regions as well as mitochondrial genome for fetuses and parents, we identified the underlying genetic causes of fetal anomalies, incidental fetal findings and parental carrier status. Information on pregnancy outcome and the impact of pES findings on parental decision-making was collected. RESULTS Of the 90 pregnancies included, 28 (31.1%) received a diagnostic result that could explain the fetal ultrasound anomalies. The highest diagnostic yield was noted for brain abnormalities (3/6 (50.0%)), followed by hydrops (4/9 (44.4%)) and skeletal abnormalities (13/34 (38.2%)). Collectively, 34 variants of 20 genes were detected in the 28 diagnosed cases, with 55.9% (19/34) occurring de novo. Variants of uncertain significance (VUS) associated with fetal phenotypes were detected in six (6.7%) fetuses. Interestingly, fetal (n = 4) and parental (n = 3) incidental findings (IFs) were detected in seven (7.8%) cases. These included two fetuses carrying a de-novo likely pathogenic (LP) variant of the CIC and FBXO11 genes, respectively, associated with neurodevelopmental disorders, and one fetus with a LP variant in a mitochondrial gene. The remaining fetus presented with unilateral renal dysplasia and was incidentally found to carry a pathogenic PKD1 gene variant resulting in adult-onset polycystic kidney, which was later confirmed to be inherited from the mother. In addition, parental heterozygous variants associated with autosomal recessive diseases were detected in three families, including one with additional fetal diagnostic findings. Diagnostic results or fetal IFs contributed to parental decision-making about termination of the pregnancy in 26 families (26/72 (36.1%)), while negative pES results or identification of VUS encouraged 40 families (40/72 (55.6%)) to continue their pregnancy, which ended in a live birth in all cases. CONCLUSION Trio-based pES can provide additional genetic information for pregnancies with fetal ultrasound anomalies without a CNV-seq diagnosis. The incidental findings and parental carrier status reported by trio-based pES with splice-site and mitochondrial genome analysis extend its clinical application, but careful genetic counseling is warranted. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.
Collapse
Affiliation(s)
- X Zhu
- Genetics and Prenatal Diagnosis Center, Department of Obstetrics and Gynecology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Z Gao
- Genetics and Prenatal Diagnosis Center, Department of Obstetrics and Gynecology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Y Wang
- Genetics and Prenatal Diagnosis Center, Department of Obstetrics and Gynecology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - W Huang
- Genetics and Prenatal Diagnosis Center, Department of Obstetrics and Gynecology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Q Li
- Genetics and Prenatal Diagnosis Center, Department of Obstetrics and Gynecology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Z Jiao
- Genetics and Prenatal Diagnosis Center, Department of Obstetrics and Gynecology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - N Liu
- Genetics and Prenatal Diagnosis Center, Department of Obstetrics and Gynecology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - X Kong
- Genetics and Prenatal Diagnosis Center, Department of Obstetrics and Gynecology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| |
Collapse
|
10
|
Chinoy A, Iruloh C, Kerr B, Mughal MZ, Padidela R. Normal Mid-Gestation Fetal Ultrasonography Cannot Reliably Exclude Severe Perinatal Hypophosphatasia. Horm Res Paediatr 2022; 94:307-312. [PMID: 34438404 DOI: 10.1159/000519209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2021] [Accepted: 07/22/2021] [Indexed: 11/19/2022] Open
Abstract
INTRODUCTION Hypophosphatasia is a systemic bone disease characterized by inhibition of bone mineralization due to mutations in the ALPL gene that results in a deficiency of tissue nonspecific alkaline phosphatase. The perinatal form is the most severe. In the past, this form was lethal, although human recombinant enzyme replacement therapy has now been developed and licensed, which improves survival. Perinatal hypophosphatasia is usually suggested on antenatal ultrasonography with undermineralization of the long bones, skull, and thoracic cavity. In the UK, antenatal ultrasonography for fetal anomalies is conducted at mid-gestation (i.e., 18-21 weeks gestational age), and if normal, no further routine scans are performed. Usually, this would identify abnormalities in bone mineralization suggestive of perinatal hypophosphatasia. CASES We describe 2 cases of perinatal hypophosphatasia where mid-gestation ultrasonography was normal. In the first case, where a previous pregnancy had been terminated for perinatal hypophosphatasia, third trimester ultrasonography revealed skeletal features of hypophosphatasia. In the second case, the diagnosis of perinatal hypophosphatasia was made only immediately after birth. CONCLUSION We conclude that serial antenatal ultrasonography or antenatal genetic testing should be considered in all pregnancies with a positive family history of hypophosphatasia, as mid-gestation ultrasonography cannot reliably exclude perinatal hypophosphatasia. This is especially important given that effective enzyme replacement therapy is now available.
Collapse
Affiliation(s)
- Amish Chinoy
- Department of Paediatric Endocrinology, Royal Manchester Children's Hospital, Manchester, United Kingdom.,Faculty of Biology, Medicine & Health, University of Manchester, Manchester, United Kingdom
| | - Chibuike Iruloh
- Fetal Medicine Unit, St. Mary's Hospital, Manchester, United Kingdom
| | - Bronwyn Kerr
- Division of Evolution and Genomic Sciences, School of Biological Sciences, University of Manchester, Manchester, United Kingdom
| | - M Zulf Mughal
- Department of Paediatric Endocrinology, Royal Manchester Children's Hospital, Manchester, United Kingdom.,Faculty of Biology, Medicine & Health, University of Manchester, Manchester, United Kingdom
| | - Raja Padidela
- Department of Paediatric Endocrinology, Royal Manchester Children's Hospital, Manchester, United Kingdom.,Faculty of Biology, Medicine & Health, University of Manchester, Manchester, United Kingdom
| |
Collapse
|
11
|
Junkiert-Czarnecka A, Pilarska-Deltow M, Bąk A, Heise M, Latos-Bieleńska A, Zaremba J, Bartoszewska-Kubiak A, Haus O. Next-Generation Sequencing of Connective Tissue Genes in Patients with Classical Ehlers-Danlos Syndrome. Curr Issues Mol Biol 2022; 44:1472-1478. [PMID: 35723357 PMCID: PMC9164033 DOI: 10.3390/cimb44040099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Revised: 03/21/2022] [Accepted: 03/23/2022] [Indexed: 11/30/2022] Open
Abstract
Background: Ehlers-Danlos syndrome (EDS) is a common non-inflammatory, congenital connective tissue disorder. Classical type (cEDS) EDS is one of the more common forms, typically caused by mutations in the COL5A1 and COL5A2 genes, though causative mutations in the COL1A1 gene have also been described. Material and methods: The study group included 59 patients of Polish origin, diagnosed with cEDS. The analysis was performed on genomic DNA (gDNA) with NGS technology, using an Illumina sequencer. Thirty-five genes related to connective tissue were investigated. The pathogenicity of the detected variants was assessed by VarSome. Results: The NGS of 35 genes revealed variants within the COL5A1, COL5A2, COL1A1, and COL1A2 genes for 30 of the 59 patients investigated. Our panel detected no sequence variations for the remaining 29 patients. Discussion: Next-generation sequencing, with an appropriate multigene panel, showed great potential to assist in the diagnosis of EDS and other connective tissue disorders. Our data also show that not all causative genes giving rise to cEDS have been elucidated yet.
Collapse
Affiliation(s)
- Anna Junkiert-Czarnecka
- Department of Clinical Genetics, Faculty of Medicine, Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Toruń, 85-094 Bydgoszcz, Poland; (M.P.-D.); (A.B.); (M.H.); (A.B.-K.); (O.H.)
- Correspondence: ; Tel.: +48-52-585-3567
| | - Maria Pilarska-Deltow
- Department of Clinical Genetics, Faculty of Medicine, Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Toruń, 85-094 Bydgoszcz, Poland; (M.P.-D.); (A.B.); (M.H.); (A.B.-K.); (O.H.)
| | - Aneta Bąk
- Department of Clinical Genetics, Faculty of Medicine, Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Toruń, 85-094 Bydgoszcz, Poland; (M.P.-D.); (A.B.); (M.H.); (A.B.-K.); (O.H.)
| | - Marta Heise
- Department of Clinical Genetics, Faculty of Medicine, Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Toruń, 85-094 Bydgoszcz, Poland; (M.P.-D.); (A.B.); (M.H.); (A.B.-K.); (O.H.)
| | - Anna Latos-Bieleńska
- Department of Medical Genetics, Poznan University of Medical Sciences, 60-352 Poznan, Poland;
| | - Jacek Zaremba
- Department of Genetics, Institute of Psychiatry and Neurology, 02-957 Warsaw, Poland;
| | - Alicja Bartoszewska-Kubiak
- Department of Clinical Genetics, Faculty of Medicine, Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Toruń, 85-094 Bydgoszcz, Poland; (M.P.-D.); (A.B.); (M.H.); (A.B.-K.); (O.H.)
| | - Olga Haus
- Department of Clinical Genetics, Faculty of Medicine, Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University in Toruń, 85-094 Bydgoszcz, Poland; (M.P.-D.); (A.B.); (M.H.); (A.B.-K.); (O.H.)
| |
Collapse
|
12
|
Mohamed FF, Chavez MB, de Oliveira FA, Narisawa S, Farquharson C, Millán JL, Foster BL. Perspective on Dentoalveolar Manifestations Resulting From PHOSPHO1 Loss-of-Function: A Form of Pseudohypophosphatasia? FRONTIERS IN DENTAL MEDICINE 2022; 3:826387. [PMID: 36185572 PMCID: PMC9521815 DOI: 10.3389/fdmed.2022.826387] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Mineralization of the skeleton occurs by several physicochemical and biochemical processes and mechanisms that facilitate the deposition of hydroxyapatite (HA) in specific areas of the extracellular matrix (ECM). Two key phosphatases, phosphatase, orphan 1 (PHOSPHO1) and tissue-non-specific alkaline phosphatase (TNAP), play complementary roles in the mineralization process. The actions of PHOSPHO1 on phosphocholine and phosphoethanolamine in matrix vesicles (MVs) produce inorganic phosphate (Pi) for the initiation of HA mineral formation within MVs. TNAP hydrolyzes adenosine triphosphate (ATP) and the mineralization inhibitor, inorganic pyrophosphate (PPi), to generate Pi that is incorporated into MVs. Genetic mutations in the ALPL gene-encoding TNAP lead to hypophosphatasia (HPP), characterized by low circulating TNAP levels (ALP), rickets in children and/or osteomalacia in adults, and a spectrum of dentoalveolar defects, the most prevalent being lack of acellular cementum leading to premature tooth loss. Given that the skeletal manifestations of genetic ablation of the Phospho1 gene in mice resemble many of the manifestations of HPP, we propose that Phospho1 gene mutations may underlie some cases of "pseudo-HPP" where ALP may be normal to subnormal, but ALPL mutation(s) have not been identified. The goal of this perspective article is to compare and contrast the loss-of-function effects of TNAP and PHOSPHO1 on the dentoalveolar complex to predict the likely dental phenotype in humans that may result from PHOSPHO1 mutations. Potential cases of pseudo-HPP associated with PHOSPHO1 mutations may resist diagnosis, and the dental manifestations could be a key criterion for consideration.
Collapse
Affiliation(s)
- Fatma F. Mohamed
- Division of Biosciences, College of Dentistry, The Ohio State University, Columbus, OH, United States
| | - Michael B. Chavez
- Division of Biosciences, College of Dentistry, The Ohio State University, Columbus, OH, United States
| | - Flavia Amadeu de Oliveira
- Sanford Children’s Health Research Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, United States
| | - Sonoko Narisawa
- Sanford Children’s Health Research Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, United States
| | - Colin Farquharson
- The Royal (Dick) School of Veterinary Studies (RDSVS), The Roslin Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - José Luis Millán
- Sanford Children’s Health Research Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, United States
| | - Brian L. Foster
- Division of Biosciences, College of Dentistry, The Ohio State University, Columbus, OH, United States,,Correspondence: Brian L. Foster,
| |
Collapse
|
13
|
Abstract
Hypophosphatasia (HPP) is an inherited metabolic disease caused by loss-of-function mutations in the tissue non-specific alkaline phosphatase (TNAP) gene. Reduced activity of TNAP leads to the accumulation of its substrates, mainly inorganic pyrophosphate and pyridoxal-5′-phosphate, metabolic aberrations that largely explain the musculoskeletal and systemic features of the disease. More than 400 ALPL mutations, mostly missense, are reported to date, transmitted by either autosomal dominant or recessive mode. Severe disease is rare, with incidence ranging from 1:100,000 to 1:300,000 live births, while the estimated prevalence of the less severe adult form is estimated to be between 1:3100 to 1:508, in different countries in Europe. Presentation largely varies, ranging from death in utero to asymptomatic adults. In infants and children, clinical features include skeletal, respiratory and neurologic complications, while recurrent, poorly healing fractures, muscle weakness and arthropathy are common in adults. Persistently low serum alkaline phosphatase is the cardinal biochemical feature of the disease. Management requires a dedicated multidisciplinary team. In mild cases, treatment is usually symptomatic. Severe cases, with life-threating or debilitating complications, can be successfully treated with enzyme replacement therapy with asfotase alfa.
Collapse
|
14
|
Tsai MC, Chou YY, Li CY, Wang YC, Yu HW, Chen CH, Chen PC. New Structural and Single Nucleotide Mutations in Type I and Type II Collagens in Taiwanese Children With Type I and Type II Collagenopathies. Front Genet 2021; 12:594285. [PMID: 34394176 PMCID: PMC8355745 DOI: 10.3389/fgene.2021.594285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Accepted: 06/22/2021] [Indexed: 11/21/2022] Open
Abstract
Collagenopathy is a rare genetic condition characterized by abnormality in either collagen structure or metabolism. Variations in its clinical presentations highlight diversity in the genetic causes and potential existence of concurrent mutations. Through whole exome sequencing (WES) complemented with multiplex ligation-dependent probe amplification, we identified the genetic etiologies for six cases with osteogenesis imperfecta (OI) in COL1A1 (p.T1298N, p.Q1280Pfs∗51, and p.G557Vfs∗23) and COL1A2 (c.1-1677_133-441del) as well as three cases with spondyloepiphyseal dysplasia congenita in COL2A1 (p.G1041S, p.G654S, and p.G441A). Co-occurrence of COL1A1 and WNT1 mutations was found in a patient with a mild OI phenotype but severe osteoporosis. These findings extended the pathogenic variant spectrum of COL1A1, COL1A2, and COL2A1 for type I and type II collagenopathies. Although WES provides a fast and accurate method to identify the genetic causes in most of the patients with type I and type II collagenopathies, its limitation of detecting CNVs because of variable capturing uniformity should be kept in mind when interpreting the results. Taken together, we demonstrate that multiple genetic characterizing technologies can provide an accurate and efficient molecular diagnostic of new genetic variants in disease-causing genes that are compatible with clinical phenotypes.
Collapse
Affiliation(s)
- Meng-Che Tsai
- Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan.,Depatment of Pediatrics, College of Medicine, National Cheng Kung University Hospital, National Cheng Kung University, Tainan, Taiwan
| | - Yen-Yin Chou
- Depatment of Pediatrics, College of Medicine, National Cheng Kung University Hospital, National Cheng Kung University, Tainan, Taiwan
| | - Chia-Yi Li
- Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Yi-Chieh Wang
- Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Hui-Wen Yu
- Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Chia-Hsiang Chen
- Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Peng-Chieh Chen
- Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan.,Research Center of Clinical Medicine, College of Medicine, National Cheng Kung University Hospital, National Cheng Kung University, Tainan, Taiwan
| |
Collapse
|
15
|
Hepp N, Frederiksen AL, Duno M, Præst Holm J, Rye Jørgensen N, Beck Jensen JE. Biochemical, clinical and genetic characteristics in adults with persistent hypophosphatasaemia; Data from an endocrinological outpatient clinic in Denmark. Bone Rep 2021; 15:101101. [PMID: 34258332 PMCID: PMC8256181 DOI: 10.1016/j.bonr.2021.101101] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 06/18/2021] [Accepted: 06/23/2021] [Indexed: 12/18/2022] Open
Abstract
Background Hypophosphatasia (HPP) is an inborn disease caused by pathogenic variants in ALPL. Low levels of alkaline phosphatase (ALP) are a biochemical hallmark of the disease. Scarce knowledge about the prevalence of HPP in Scandinavia exists, and the variable clinical presentations make diagnostics challenging. The aim of this study was to investigate the prevalence of ALPL variants as well as the clinical and biochemical features among adults with endocrinological diagnoses and persistent hypophosphatasaemia. Methods A biochemical database containing ALP measurements of 26,121 individuals was reviewed to identify adults above 18 years of age with persistently low levels of ALP beneath range (≤ 35 ± 2.7 U/L). ALPL genetic testing, biochemical evaluations and assessment of clinical features by a systematic questionnaire among included patients, were performed. Results Among 24 participants, thirteen subjects (54.2%) revealed a disease-causing variant in ALPL and reported mild clinical features of HPP, of which musculoskeletal pain was the most frequently reported (n = 9). The variant c. 571G > A; p.(Glu191Lys) was identified in six subjects, and an unreported missense variant (c.1019A > C; p.(His340Pro)) as well as a deletion of exon 2 were detected by genetic screening. Biochemical analyses showed no significant differences in ALP (p = 0.059), the bone specific alkaline phosphatase (BALP) (p = 0.056) and pyridoxal-5′-phosphate (PLP) (p = 0.085) between patients with an ALPL variant and negative genetic screening. Patients with a variant in ALPL had significantly higher PLP levels than healthy controls (p = 0.002). We observed normal ALP activity in some patients classified as mild HPP, and slightly increased levels of PLP in two subjects with normal genetic screening and four healthy controls. Among 51 patients with persistent hypophosphatasaemia, fifteen subjects (29.4%) received antiresorptive treatment. Two patients with unrecognized HPP were treated with bisphosphonates and did not show complications due to the treatment. Conclusions Pathogenic variants in ALPL are common among patients with endocrinological diagnoses and low ALP. Regarding diagnostics, genetic testing is necessary to identify mild HPP due to fluctuating biochemical findings. Antiresorptive treatment is a frequent reason for hypophosphatasaemia and effects of these agents in adults with a variant in ALPL and osteoporosis remain unclear and require further studies. Mild HPP is overlooked among adults with endocrinological diagnoses. Biochemical hallmarks of HPP can fluctuate to normal among mild forms. Genetic screening of ALPL including MLPA is necessary to identify mild HPP. Musculoskeletal pain is the most common symptom in adult HPP. Effects of bisphosphonates in mild HPP need further studies.
Collapse
Affiliation(s)
- Nicola Hepp
- Dept. of Endocrinology, Hvidovre University Hospital Copenhagen, Kettegaard Alle 30, 2650 Hvidovre, Denmark
| | - Anja Lisbeth Frederiksen
- Dept. of Clinical Genetics, Aalborg University Hospital, Ladegaardsgade 5, 9000 Aalborg C, Denmark.,Dept. of Clinical Research, Aalborg University, Fredrik Bajers Vej 7K, 9220 Aalborg Ø, Denmark
| | - Morten Duno
- Dept. of Clinical Genetics, University Hospital Copenhagen Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark
| | - Jakob Præst Holm
- Department of Endocrinology, Copenhagen University Hospital Herlev, Borgmester Ib Juuls Vej 1, 2730 Herlev, Denmark
| | - Niklas Rye Jørgensen
- Dept. of Clinical Biochemistry, Rigshospitalet, Valdemar Hansens Vej 13, 2600 Glostrup, Denmark.,Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3 B, 2200 Copenhagen, Denmark
| | - Jens-Erik Beck Jensen
- Dept. of Endocrinology, Hvidovre University Hospital Copenhagen, Kettegaard Alle 30, 2650 Hvidovre, Denmark.,Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3 B, 2200 Copenhagen, Denmark
| |
Collapse
|
16
|
Butscheidt S, Tsourdi E, Rolvien T, Delsmann A, Stürznickel J, Barvencik F, Jakob F, Hofbauer LC, Mundlos S, Kornak U, Seefried L, Oheim R. Relevant genetic variants are common in women with pregnancy and lactation-associated osteoporosis (PLO) and predispose to more severe clinical manifestations. Bone 2021; 147:115911. [PMID: 33716164 DOI: 10.1016/j.bone.2021.115911] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Revised: 01/19/2021] [Accepted: 03/08/2021] [Indexed: 12/17/2022]
Abstract
Pregnancy and lactation-associated osteoporosis (PLO) is a rare skeletal disorder characterized by early-onset osteoporosis typically manifestating with vertebral compression fractures or transient osteoporosis of the hip. We hypothesized that genetic variants may play a role in the development of PLO. This study aimed to analyze the presence of genetic variants and a potential association with the clinical presentation in PLO. 42 women with PLO were included from 2013 to 2019 in a multicenter study in Germany. All cases underwent comprehensive genetic analysis based on a custom-designed gene panel including genes relevant for skeletal disorders. The skeletal status was assessed using dual-energy X-ray absorptiometry (DXA). Subgroups were further analyzed by serum bone turnover markers (n = 31) and high-resolution peripheral computed tomography (HR-pQCT; n = 23). We detected relevant genetic variants in 21 women (50%), with LRP5, WNT1 and COL1A1/A2 being the most commonly involved genes. The mean number of vertebral compression fractures was 3.3 ± 3.4 per case with a significantly higher occurrence in the subgroup with genetic variants (4.8 ± 3.7 vs. 1.8 ± 2.3, p = 0.02). Among the total cohort, DXA Z-scores were significantly lower at the lumbar spine compared to the femoral neck (p = 0.002). HR-pQCT revealed a pronounced reduction of trabecular and cortical thickness, while trabecular number was within the reference range. Eighteen women (43%) received a bone-specific therapy (primarily teriparatide). Overall, a steep increase in bone mass (+37.7%) was observed after 3 years. In conclusion, pregnancy and lactation represent skeletal risk factors, which may unmask hereditary bone disorders leading to PLO. These cases were affected more severely. Nevertheless, a timely diagnosis and adequate treatment can ensure a substantial recovery potential even without specific therapy. Patients with genetically induced low bone turnover (e.g.; LRP5, WNT1) may especially benefit from osteo-anabolic medication.
Collapse
Affiliation(s)
- Sebastian Butscheidt
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany; Division of Orthopaedics, Department of Trauma and Orthopaedic Surgery, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Elena Tsourdi
- Department of Medicine III, Technische Universität Dresden Medical Center, Dresden, Germany; Center for Healthy Aging, Technische Universität Dresden Medical Center, Dresden, Germany
| | - Tim Rolvien
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany; Division of Orthopaedics, Department of Trauma and Orthopaedic Surgery, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Alena Delsmann
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Julian Stürznickel
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Florian Barvencik
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Franz Jakob
- Orthopedic Center for Musculoskeletal Research, Orthopedic Department, University of Würzburg, Germany
| | - Lorenz C Hofbauer
- Department of Medicine III, Technische Universität Dresden Medical Center, Dresden, Germany; Center for Healthy Aging, Technische Universität Dresden Medical Center, Dresden, Germany
| | - Stefan Mundlos
- Institute of Medical Genetics and Human Genetics, Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Uwe Kornak
- Institute of Medical Genetics and Human Genetics, Charité Universitätsmedizin Berlin, Berlin, Germany; Institute of Human Genetics, Universitätsmedizin Göttingen, Göttingen, Germany
| | - Lothar Seefried
- Orthopedic Center for Musculoskeletal Research, Orthopedic Department, University of Würzburg, Germany
| | - Ralf Oheim
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
| |
Collapse
|
17
|
Kishnani PS, Del Angel G, Zhou S, Rush ET. Investigation of ALPL variant states and clinical outcomes: An analysis of adults and adolescents with hypophosphatasia treated with asfotase alfa. Mol Genet Metab 2021; 133:113-121. [PMID: 33814268 DOI: 10.1016/j.ymgme.2021.03.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 02/03/2021] [Accepted: 03/14/2021] [Indexed: 12/22/2022]
Abstract
BACKGROUND Hypophosphatasia (HPP), a rare metabolic disease, can be inherited in an autosomal recessive (biallelic) or an autosomal dominant (monoallelic) manner. Most of the severe, early-onset, frequently lethal HPP in infants is acquired through recessive inheritance; less severe, later-onset, typically nonlethal HPP phenotypes are acquired through either dominant or recessive inheritance. HPP's variable clinical presentation arises from >400 identified ALPL pathogenic variants with likely variable penetrance, especially with autosomal dominant inheritance. This post hoc analysis investigated the relationship between ALPL variant state (biallelic and monoallelic) and clinical outcomes with asfotase alfa in HPP. METHODS Data were pooled from two phase 2, randomized, open-label studies in adolescents and adults with HPP; one study evaluated the efficacy and safety of different doses of asfotase alfa (n = 25), and the other assessed the pharmacodynamics and safety of asfotase alfa (n = 19). Patients were grouped by ALPL variant state (biallelic or monoallelic). Available data from both studies included ALPL pathogenic variant state, Baseline characteristics, HPP-specific medical history, and Baseline TNSALP substrate levels (inorganic pyrophosphate [PPi] and pyridoxal 5'-phosphate [PLP]) concentrations). Clinical outcomes over 5 years of treatment were available from only the efficacy and safety study. RESULTS In total, 44 patients with known variant status were included in the pooled analysis (biallelic, n = 30; monoallelic, n = 14). The most common pathogenic variant was c.571G > A (p.Glu191Lys) in biallelic patients (allele frequency: 19/60) and c.1133A > T (p.Asp378Val) in monoallelic patients (allele frequency: 7/28). Median (min, max) Baseline PPi concentrations were significantly higher in patients with a biallelic vs monoallelic variant state (5.3 [2.2, 12.1] vs 4.3 [3.5, 7.4] μM; P = 0.0113), as were Baseline PLP concentrations (221.4 [62.4, 1590.0] vs 75.1 [28.8, 577.0] ng/mL; P= 0.0022). HPP-specific medical history was generally similar between biallelic and monoallelic patients in terms of incidence and type of manifestations; notable exceptions included fractures, which were more common among monoallelic patients, and delayed walking and bone deformities such as abnormally shaped chest and head and bowing of arms or legs, which were more common among biallelic patients. Data from the efficacy and safety study (n = 19) showed that median PPi and PLP concentrations were normalized over 5 years of treatment in patients with both variant states. Median % predicted distance walked on the 6-Minute Walk Test remained within the normal range for monoallelic patients over 4 years of treatment, and improved from below normal (<84%) to normal in biallelic patients. CONCLUSIONS Although patients with biallelic variants had significantly higher Baseline PPi and PLP levels than monoallelic variants, both groups generally showed similar pretreatment Baseline clinical characteristics. Treatment with asfotase alfa for up to 5 years normalized TNSALP substrate concentrations and improved functional outcomes, with no clear differences between biallelic and monoallelic variant states. This study suggests that patients with HPP have significant disease burden, regardless of ALPL variant state.
Collapse
Affiliation(s)
- Priya S Kishnani
- Department of Pediatrics, Duke University Medical Center, 2351 Erwin Road, Durham, NC, USA.
| | | | - Shanggen Zhou
- Covance, Inc., 206 Carnegie Center Dr, Princeton, NJ, USA.
| | - Eric T Rush
- Children's Mercy Hospital Kansas City, 2401 Gillham Rd, Kansas City, MO, USA; University of Missouri-Kansas City School of Medicine, Kansas City, MO, USA; University of Kansas School of Medicine, Kansas City, KS, USA.
| |
Collapse
|
18
|
Tang H, Zhang Q, Xiang J, Yin L, Wang J, Wang T. Whole Exome Sequencing Aids the Diagnosis of Fetal Skeletal Dysplasia. Front Genet 2021; 12:599863. [PMID: 33777089 PMCID: PMC7987927 DOI: 10.3389/fgene.2021.599863] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Accepted: 01/27/2021] [Indexed: 11/22/2022] Open
Abstract
Skeletal dysplasia is a complex group of bone and cartilage disorders with strong clinical and genetic heterogeneity. Several types have prenatal phenotypes, and it is difficult to make a molecular diagnosis rapidly. In this study, the genetic cause of 16 Chinese fetuses with skeletal dysplasia were analyzed, and 12 cases yielded positive results including one deletion in DMD gene detected by SNP-array and 14 variants in other 6 genes detected by whole exome sequencing (WES). In addition, somatic mosaicism was observed. Our study expanded the pathogenic variant spectrum and elucidated the utilization of WES in improving the diagnosis yield of skeletal dysplasia.
Collapse
Affiliation(s)
- Hui Tang
- Center for Reproduction and Genetics, The Affiliated Suzhou Hospital of Nanjing Medical University, Suzhou, China
- Center for Reproduction and Genetics, Suzhou Municipal Hospital, Suzhou, China
| | - Qin Zhang
- Center for Reproduction and Genetics, The Affiliated Suzhou Hospital of Nanjing Medical University, Suzhou, China
- Center for Reproduction and Genetics, Suzhou Municipal Hospital, Suzhou, China
| | - Jingjing Xiang
- Center for Reproduction and Genetics, The Affiliated Suzhou Hospital of Nanjing Medical University, Suzhou, China
- Center for Reproduction and Genetics, Suzhou Municipal Hospital, Suzhou, China
| | - Linliang Yin
- Center for Reproduction and Genetics, The Affiliated Suzhou Hospital of Nanjing Medical University, Suzhou, China
- Center for Reproduction and Genetics, Suzhou Municipal Hospital, Suzhou, China
| | - Jing Wang
- Suzhou Guangji Hospital, Suzhou, China
| | - Ting Wang
- Center for Reproduction and Genetics, The Affiliated Suzhou Hospital of Nanjing Medical University, Suzhou, China
- Center for Reproduction and Genetics, Suzhou Municipal Hospital, Suzhou, China
| |
Collapse
|
19
|
Laroche M, Couture G, Faruch M, Ruyssen-Witrand A, Porquet-Bordes V, Salles JP, Degboe Y. Hypophosphatasia: A Case of Two Patients With Spinal Cord Compression From Increase in Ligamentous Ossifications During Treatment. JBMR Plus 2021; 5:e10449. [PMID: 33869986 PMCID: PMC8046109 DOI: 10.1002/jbm4.10449] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Accepted: 11/08/2020] [Indexed: 11/20/2022] Open
Abstract
Treatment with asfotase alfa has transformed the prognosis of hypophosphatasia in children and improves the bone and muscle signs in adults. The doses used in adults are the same as in children, whereas bone remodeling is different between them. We report on the cases of two patients treated with 1 mg/kg/day of asfotase alfa who developed spinal cord compression from spinal ossifications during treatment. The first patient, 50 years old, presented after 2 years of treatment with quadraparesis secondary to an increase in ossifications of the cervical vertebral ligaments. The neurological damage was resolved after laminectomy, and the patient was then treated for 18 months with doses of 80 mg per week, without recurrence of the bone and muscle signs. The second patient, 26 years old, 78 kg, developed pain and cervical stiffness with pyramidal tract irritation secondary to ossifications of the vertebral ligaments. This improved with a reduction of doses to 80 mg/week, which then, after 6 months of follow‐up, enabled maintained improvement of the bone and muscle pain that was initially obtained. To our knowledge, these are the first reported cases of increased spinal ligamentous ossifications with neurological complications. Biological monitoring in adults does not seem to enable asfotase alfa doses to be adjusted. The levels of serum alkaline phosphatase (ALP) while on the recommended treatment of 1 mg/kg/day are significantly supraphysiological (5000 to 20,000 IU) and the assays of pyrophosphate and pyridoxal phosphate are not correlated with clinical efficacy. In both of our patients, the treatment with 80 mg of asfotase alfa per week, which was proposed after the occurrence of spinal complications, seemed as effective, after a follow‐up of 18 months and 6 months, as the initial treatment for improving the bone and muscle signs, and could be provided as “attack” doses after healing of the pseudoarthroses. © 2021 American Society for Bone and Mineral Research © 2020 The Authors. JBMR Plus published by Wiley Periodicals LLC. on behalf of American Society for Bone and Mineral Research.
Collapse
Affiliation(s)
- Michel Laroche
- Centre de Rhumatologie du Centre Hospitalo-Universitaire de Toulouse [Rheumatology Center of Toulouse University Hospital] Toulouse France
| | - Guillaume Couture
- Centre de Rhumatologie du Centre Hospitalo-Universitaire de Toulouse [Rheumatology Center of Toulouse University Hospital] Toulouse France
| | - Marie Faruch
- Service de Radiologie du Centre Hospitalo-Universitaire de Toulouse [Department of Radiology of Toulouse University Hospital] Toulouse France
| | - Adeline Ruyssen-Witrand
- Centre de Rhumatologie du Centre Hospitalo-Universitaire de Toulouse [Rheumatology Center of Toulouse University Hospital] Toulouse France
| | - Valérie Porquet-Bordes
- Endocrinologie, Maladies Osseuses, Hôpital des Enfants, Centre de Référence des Maladies Rares du Métabolisme du Calcium et Phosphate, European Reference Network on rare bone diseases, Centre Hospitalo-Universitaire de Toulouse Toulouse France
| | - Jean Pierre Salles
- Endocrinologie, Maladies Osseuses, Hôpital des Enfants, Centre de Référence des Maladies Rares du Métabolisme du Calcium et Phosphate, European Reference Network on rare bone diseases, Centre Hospitalo-Universitaire de Toulouse Toulouse France.,INSERM UMR 1043 CNRS5825, Centre de Physiopathologie de Toulouse Purpan, Centre de Physiopathology Toulouse Purpan, Université de Toulouse Toulouse France
| | - Yannick Degboe
- Centre de Rhumatologie du Centre Hospitalo-Universitaire de Toulouse [Rheumatology Center of Toulouse University Hospital] Toulouse France.,INSERM UMR 1043 CNRS5825, Centre de Physiopathologie de Toulouse Purpan, Centre de Physiopathology Toulouse Purpan, Université de Toulouse Toulouse France
| |
Collapse
|
20
|
Sperelakis-Beedham B, Taillandier A, Domingues C, Guberto M, Colin E, Porquet-Bordes V, Rothenbuhler A, Salles JP, Wenkert D, Zankl A, Muti C, Bacrot S, Simon-Bouy B, Mornet E. Utility of genetic testing for prenatal presentations of hypophosphatasia. Mol Genet Metab 2021; 132:198-203. [PMID: 33549410 DOI: 10.1016/j.ymgme.2021.01.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 01/18/2021] [Accepted: 01/19/2021] [Indexed: 01/13/2023]
Abstract
Hypophosphatasia (HPP) is a rare inherited disease affecting bone and dental mineralization due to loss-of-function mutations in the ALPL gene encoding the tissue nonspecific alkaline phosphatase (TNSALP). Prenatal benign HPP (PB HPP) is a rare form of HPP characterized by in utero skeletal manifestations that progressively improve during pregnancy but often still leave symptoms after birth. Because the prenatal context limits the diagnostic tools, the main difficulty for clinicians is to distinguish PB HPP from perinatal lethal HPP, the most severe form of HPP. We previously attempted to improve genotype phenotype correlation with the help of a new classification of variants based on functional testing. Among 46 perinatal cases detected in utero or in the neonatal period for whose ALPL variants could be classified, imaging alone was thought to clearly diagnose severe lethal HPP in 35 cases, while in 11 cases, imaging abnormalities could not distinguish between perinatal lethal and BP HPP. We show here that our classification of ALPL variants may improve the ability to distinguish between perinatal lethal and PB HPP in utero.
Collapse
Affiliation(s)
| | - Agnès Taillandier
- Unité de Génétique constitutionnelle, Centre Hospitalier de Versailles, Le Chesnay, France
| | - Christelle Domingues
- Unité de Génétique constitutionnelle, Centre Hospitalier de Versailles, Le Chesnay, France
| | - Mihelaiti Guberto
- Unité de Génétique constitutionnelle, Centre Hospitalier de Versailles, Le Chesnay, France
| | | | - Valérie Porquet-Bordes
- Pédiatrie - Endocrinologie, génétique et gynécologie médicale, Hôpital des enfants (CHU Toulouse), Toulouse, France
| | - Anya Rothenbuhler
- Service d'endocrinologie et diabète de l'enfant, Hôpital Bicêtre (Hôpitaux Universitaires Paris Saclay - APHP), Paris, France
| | - Jean-Pierre Salles
- Pédiatrie - Endocrinologie, génétique et gynécologie médicale, Hôpital des enfants (CHU Toulouse), Toulouse, France
| | - Deborah Wenkert
- Center for Metabolic Bone Disease and Molecular Research, Shriners Hospitals for Children - St. Louis, St. Louis, MO 63110, USA; Wenkert & Young, LLC, Thousand Oaks, CA 91362, USA
| | - Andreas Zankl
- Department of Clinical Genetics, Sydney Children's Hospital Network (Westmead), Westmead, Australia; Faculty of Medicine and Health, The University of Sydney, Sydney, Australia; Bone Biology Division and Kinghorn Centre for Clinical Genomics, Garvan Institute of Medical Research, Darlinghurst, Australia
| | - Christine Muti
- Unité de Génétique constitutionnelle, Centre Hospitalier de Versailles, Le Chesnay, France
| | - Séverine Bacrot
- Unité de Génétique constitutionnelle, Centre Hospitalier de Versailles, Le Chesnay, France
| | - Brigitte Simon-Bouy
- Unité de Génétique constitutionnelle, Centre Hospitalier de Versailles, Le Chesnay, France
| | - Etienne Mornet
- Unité de Génétique constitutionnelle, Centre Hospitalier de Versailles, Le Chesnay, France.
| |
Collapse
|
21
|
Estimation of the carrier frequencies and proportions of potential patients by detecting causative gene variants associated with autosomal recessive bone dysplasia using a whole-genome reference panel of Japanese individuals. Hum Genome Var 2021; 8:2. [PMID: 33452237 PMCID: PMC7810679 DOI: 10.1038/s41439-020-00133-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 12/07/2020] [Accepted: 12/08/2020] [Indexed: 12/04/2022] Open
Abstract
Bone dysplasias are a group of rare hereditary diseases, with up to 436 disease types. Perinatal diagnosis is clinically important for adequate personalized management and counseling. There are no reports focused on pathogenic variants of bone dysplasias in the general population. In this study, we focused on autosomal recessive bone dysplasias. We identified pathogenic variants using whole-genome reference panel data from 3552 Japanese individuals. For the first time, we were able to estimate the carrier frequencies and the proportions of potential patients. For autosomal recessive bone dysplasias, we detected 198 pathogenic variants of 54 causative genes. We estimated the variant carrier frequencies and the proportions of potential patients with variants associated with four clinically important bone dysplasias: osteogenesis imperfecta (OI), hypophosphatasia (HPP), asphyxiating thoracic dysplasia (ATD), and Ellis–van Creveld syndrome (EvC). The proportions of potential patients with OI, ATD, and EvC based on pathogenic variants classified as “pathogenic” and “likely pathogenic” by InterVar were closer to the reported incidence rates in Japanese subjects. Furthermore, the proportions of potential patients with HPP variants classified as “pathogenic” and “likely pathogenic” in InterVar and “pathogenic” in ClinVar were closer to the reported incidence rates. For bone dysplasia, the findings of this study will provide a better understanding of the variant types and frequencies in the Japanese general population, and should be useful for clinical diagnosis, genetic counseling, and personalized medicine. A bioinformatics approach helps estimate carrier frequency of a rare inherited bone disease which causes abnormalities in skeletal shape and structure. Autosomal recessive bone dysplasias affect bone and cartilage development and result from inheriting two mutated genes, one from each parent. Junichi Sugawara, Tohoku University, Sendai, Japan, and colleagues used mutation databases and a bioinformatics tool for variant interpretation to detect 198 pathogenic variants in 54 genes associated with autosomal recessive bone dysplasia in a whole-genome reference panel of 3,552 general Japanese individuals (3.5KJPNv2). They then estimated the frequency of people in the sample carrying bone dysplasia mutations and the expected proportion in whom the disorder could manifest, which compared well with reported incidence rates in the general population. These findings could prove useful for calculating the risk of bone dysplasia in the future children of carrier parents.
Collapse
|
22
|
Mornet E, Taillandier A, Domingues C, Dufour A, Benaloun E, Lavaud N, Wallon F, Rousseau N, Charle C, Guberto M, Muti C, Simon-Bouy B. Hypophosphatasia: a genetic-based nosology and new insights in genotype-phenotype correlation. Eur J Hum Genet 2020; 29:289-299. [PMID: 32973344 DOI: 10.1038/s41431-020-00732-6] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Revised: 09/08/2020] [Accepted: 09/15/2020] [Indexed: 11/09/2022] Open
Abstract
Hypophosphatasia (HPP) is caused by pathogenic variants in the ALPL gene. There is a large continuum in the severity, ranging from a lethal perinatal form to dental issues. We analyzed a cohort of 424 HPP patients from European geographic origin or ancestry. Using 3D modeling and results of functional tests we classified ALPL pathogenic variants according to their dominant negative effect (DNE) and their severity. The cohort was described by the genotypes resulting from alleles s (severe recessive), Sd (severe dominant), and m (moderate). Many recurrent variants showed a regional anchor pointing out founder effects rather than multiple mutational events. Homozygosity was an aggravating factor of the severity and moderate alleles were rare both in number and frequency. Pathogenic variants with DNE were found in both recessive and dominant HPP. Sixty percent of the adults tested were heterozygous for a variant showing no DNE, suggesting another mechanism of dominance like haploinsufficiency. Adults with dominant HPP without DNE were found statistically less severely affected than adults with DNE variants. Adults with dominant HPP without DNE represent a new clinical entity mostly diagnosed from 2010s, characterized by nonspecific signs of HPP and low alkaline phosphatase, and for which a high prevalence is expected. In conclusion, the genetic composition of our cohort suggests a nosology with 3 clinical forms: severe HPP is recessive and rare, moderate HPP is recessive or dominant and more common, and mild HPP, characterized by low alkaline phosphatase and unspecific clinical signs, is dominantly inherited and very common.
Collapse
Affiliation(s)
- Etienne Mornet
- Unité de Génétique Constitutionnelle, Service de Biologie, Centre Hospitalier de Versailles, 78150, Le Chesnay, France.
| | - Agnès Taillandier
- Unité de Génétique Constitutionnelle, Service de Biologie, Centre Hospitalier de Versailles, 78150, Le Chesnay, France
| | - Christelle Domingues
- Unité de Génétique Constitutionnelle, Service de Biologie, Centre Hospitalier de Versailles, 78150, Le Chesnay, France
| | - Annika Dufour
- Unité de Génétique Constitutionnelle, Service de Biologie, Centre Hospitalier de Versailles, 78150, Le Chesnay, France
| | - Emmanuelle Benaloun
- Unité de Génétique Constitutionnelle, Service de Biologie, Centre Hospitalier de Versailles, 78150, Le Chesnay, France
| | - Nicole Lavaud
- Unité de Génétique Constitutionnelle, Service de Biologie, Centre Hospitalier de Versailles, 78150, Le Chesnay, France
| | - Fabienne Wallon
- Unité de Génétique Constitutionnelle, Service de Biologie, Centre Hospitalier de Versailles, 78150, Le Chesnay, France
| | - Nathalie Rousseau
- Unité de Génétique Constitutionnelle, Service de Biologie, Centre Hospitalier de Versailles, 78150, Le Chesnay, France
| | - Carole Charle
- Unité de Génétique Constitutionnelle, Service de Biologie, Centre Hospitalier de Versailles, 78150, Le Chesnay, France
| | - Mihelaiti Guberto
- Unité de Génétique Constitutionnelle, Service de Biologie, Centre Hospitalier de Versailles, 78150, Le Chesnay, France
| | - Christine Muti
- Unité de Génétique Constitutionnelle, Service de Biologie, Centre Hospitalier de Versailles, 78150, Le Chesnay, France
| | - Brigitte Simon-Bouy
- Unité de Génétique Constitutionnelle, Service de Biologie, Centre Hospitalier de Versailles, 78150, Le Chesnay, France
| |
Collapse
|
23
|
Tilden DR, Sheehan JH, Newman JH, Meiler J, Capra JA, Ramirez A, Simmons J, Dahir K. Phenotypic Profiling in Subjects Heterozygous for 1 of 2 Rare Variants in the Hypophosphatasia Gene ( ALPL). J Endocr Soc 2020; 4:bvaa084. [PMID: 32803091 PMCID: PMC7417882 DOI: 10.1210/jendso/bvaa084] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Accepted: 06/22/2020] [Indexed: 11/19/2022] Open
Abstract
Context Hypophosphatasia (HPP) is a syndrome marked by low serum alkaline phosphatase (AlkP) activity as well as musculoskeletal and/or dental disease. While the majority of subjects with HPP carry a pathogenic variant in the ALPL gene or its regulatory regions, individual pathogenic variants are often not tightly correlated with clinical symptomatology. We sought to better understand the genotype/phenotype correlation in HPP by examining the clinical and biochemical data of 37 subjects with 2 rare variants in ALPL. Methods Through BioVU, a DNA biobank that pairs individuals’ genetic information with their de-identified medical records, we identified subjects with 2 rare variants with distinct reported clinical phenotypes (p.D294A and p.T273M). We then performed a manual review of these subjects’ de-identified medical records along with computational modeling of protein structure to construct a genetic, biochemical and clinical phenotype for each subject and variant. Results Twenty subjects with the p.D294A variant and 17 with the p.T273M variant had sufficient data for analysis. Among subjects in our cohort with the p.D294A variant, 6 (30.0%) had both clinical bone disease and serum AlkP activity below 40 IU/L while 4 subjects (23.5%) with the p.T273M variant met the same criteria despite the distinct clinical phenotypes of these variants. Conclusions Given the loose genotype/phenotype correlation in HPP seen in our cohort, clinical context is crucial for the interpretation of genetic test results to guide clinical care in this population. Otherwise, over- or under-diagnosis may occur, resulting in misidentification of those who may benefit from additional screening and perhaps pharmacologic intervention.
Collapse
Affiliation(s)
- Daniel R Tilden
- Division of Endocrinology, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee.,Ian M. Burr Division of Pediatric Endocrinology, Department of Pediatrics, Monroe Carroll Jr. Children's Hospital at Vanderbilt, Nashville, Tennessee
| | - Jonathan H Sheehan
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - John H Newman
- Division of Allergy, Pulmonary and Critical Care Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Jens Meiler
- Center for Structural Biology, Vanderbilt University Medical Center Nashville, TN.,Department of Chemistry, Vanderbilt University Medical Center, Nashville, Tennessee.,Department of Pharmacology, Vanderbilt University Medical Center, Nashville, Tennessee
| | - John A Capra
- Center for Structural Biology, Vanderbilt University Medical Center Nashville, TN.,Department of Chemistry, Vanderbilt University Medical Center, Nashville, Tennessee.,Department of Biological Sciences and Biomedical Informatics, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Andrea Ramirez
- Division of Endocrinology, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Jill Simmons
- Ian M. Burr Division of Pediatric Endocrinology, Department of Pediatrics, Monroe Carroll Jr. Children's Hospital at Vanderbilt, Nashville, Tennessee
| | - Kathryn Dahir
- Division of Endocrinology, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
| |
Collapse
|
24
|
Tornero C, Navarro-Compán V, Tenorio JA, García-Carazo S, Buño A, Monjo I, Plasencia-Rodriguez C, Iturzaeta JM, Lapunzina P, Heath KE, Balsa A, Aguado P. Can we identify individuals with an ALPL variant in adults with persistent hypophosphatasaemia? Orphanet J Rare Dis 2020; 15:51. [PMID: 32066479 PMCID: PMC7026995 DOI: 10.1186/s13023-020-1315-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2019] [Accepted: 01/24/2020] [Indexed: 12/19/2022] Open
Abstract
Background Hypophosphatasia (HPP) is an inborn error of metabolism characterized by low levels of serum alkaline phosphatase (ALP). Scarce evidence exists about features that should signal the potential association between hypophosphatasaemia and HPP in adults. The aim of this study is to estimate the prevalence of ALPL variants in subjects with persistent hypophosphatasaemia and determine the associated clinical and laboratory features. For this cross-sectional study, laboratory records of 386,353 subjects were screened by measurement of ALP activity. A total of 85 (0.18%) subjects with persistent hypophosphatasaemia (≥2 serum alkaline phosphatase–ALP–measurements ≤35 IU/L and none > 45 IU/L) were included (secondary causes previously discarded). ALPL genetic testing and a systematized questionnaire to retrieve demographic, clinical and laboratory data were performed. Descriptive analysis and logistic regression models were employed to identify the clinical and laboratory characteristics associated with ALPL variants. Results Forty subjects (47%) had a variant(s) in ALPL. With regard to clinical characteristics, the presence of an ALPL variant was significantly associated only with musculoskeletal pain (OR: 7.6; 95% IC: 1.9–30.9). Nevertheless, a trend to present more dental abnormalities (OR: 3.6; 95% IC: 0.9–13.4) was observed. Metatarsal stress fractures were also more frequent (4 vs 0; p < 0.05) in this group. Regarding laboratory features, median ALP levels were lower in subjects with ALPL variants (26 vs 29 IU/L; p < 0.005). Interestingly, the threshold of ALP levels < 25 IU/L showed a specificity, positive predictive value and positive likelihood ratio of 97.8, 94.4% and 19.8 to detect a positive ALPL test, respectively. Conclusions In subjects with persistent hypophosphatasaemia –secondary causes excluded– one out of two presented ALPL variants. Musculoskeletal pain and ALP levels < 25 IU/L are associated with this variant(s). In this scenario, ALP levels < 25 IU/L seem to be very useful to identify individuals with the presence of an ALPL variant.
Collapse
Affiliation(s)
- C Tornero
- Department of Rheumatology, La Paz University Hospital, IdiPAZ, Paseo de la Castellana, 261, 28046, Madrid, Spain.
| | - V Navarro-Compán
- Department of Rheumatology, La Paz University Hospital, IdiPAZ, Paseo de la Castellana, 261, 28046, Madrid, Spain
| | - J A Tenorio
- Institute of Medical and Molecular Genetics (INGEMM), La Paz University Hospital, IdiPAZ, Universidad Autónoma de Madrid, Madrid, Spain.,CIBERER (Centro de Investigación Biomédica en Red de Enfermedades Raras), ISCIII, Madrid, Spain
| | - S García-Carazo
- Department of Rheumatology, La Paz University Hospital, IdiPAZ, Paseo de la Castellana, 261, 28046, Madrid, Spain
| | - A Buño
- Department of Clinical Biochemistry, La Paz University Hospital, Madrid, Spain
| | - I Monjo
- Department of Rheumatology, La Paz University Hospital, IdiPAZ, Paseo de la Castellana, 261, 28046, Madrid, Spain
| | - C Plasencia-Rodriguez
- Department of Rheumatology, La Paz University Hospital, IdiPAZ, Paseo de la Castellana, 261, 28046, Madrid, Spain
| | - J M Iturzaeta
- Department of Clinical Biochemistry, La Paz University Hospital, Madrid, Spain
| | - P Lapunzina
- Institute of Medical and Molecular Genetics (INGEMM), La Paz University Hospital, IdiPAZ, Universidad Autónoma de Madrid, Madrid, Spain.,CIBERER (Centro de Investigación Biomédica en Red de Enfermedades Raras), ISCIII, Madrid, Spain
| | - K E Heath
- Institute of Medical and Molecular Genetics (INGEMM), La Paz University Hospital, IdiPAZ, Universidad Autónoma de Madrid, Madrid, Spain.,CIBERER (Centro de Investigación Biomédica en Red de Enfermedades Raras), ISCIII, Madrid, Spain.,Skeletal dysplasia multidisciplinary Unit (UMDE), La Paz University Hospital, Madrid, Spain
| | - A Balsa
- Department of Rheumatology, La Paz University Hospital, IdiPAZ, Paseo de la Castellana, 261, 28046, Madrid, Spain
| | - P Aguado
- Department of Rheumatology, La Paz University Hospital, IdiPAZ, Paseo de la Castellana, 261, 28046, Madrid, Spain
| |
Collapse
|
25
|
Abstract
Hypophosphatasia (HPP) is a rare inherited systemic metabolic disease caused by mutations in the tissue-nonspecific alkaline phosphatase (TNSALP) gene. TNSALP is expressed in the liver, kidney and bone, and its substrates include TNSALP inorganic pyrophosphate, pyridoxal-5'-phosphate (PLP)/vitamin B6 and phosphoethanolamine (PEA). Autosomal recessive and dominant forms of the disease result in a range of clinical entities. Major hallmarks are low alkaline phosphatase (ALP) and elevated PLP and PEA levels. Very severe infantile forms of HPP cause premature death as a result of respiratory insufficiency and also present with hypo-mineralisation leading to deformed limbs with, in some cases, the near-absence of bones and skull altogether. Respiratory failure, rib fractures and seizures due to vitamin B6 deficiency are indicative of a poor prognosis. Craniosynostosis is frequent. HPP leads to an unusual presentation of rickets with high levels of calcium and phosphorus, resulting in hypercalciuria, nephrocalcinosis and low ALP levels. Hypercalcaemic crisis, failure to thrive and growth retardation are concerns in infants. Fractures are common in both infantile and adult forms of the disease, concomitantly occurring with unexplained chronic pain and fatigue. Dental clinical presentations, which include the premature loss of teeth, are also commonly found in HPP and specifically manifest as odontohypophosphatasia. A novel enzyme therapy for human HPP, asfotase alfa, which is specifically targeted to mineralised tissues, has been developed in the past decades. While this treatment seems very promising, especially for infantile HPP, many questions regarding its long-term effects, the management of treatment, and any potential secondary adverse effects remain unresolved.
Collapse
|
26
|
Isik E, Onay H, Atik T, Canda E, Cogulu O, Coker M, Ozkinay F. Clinical utility of a targeted next generation sequencing panel in severe and pediatric onset Mendelian diseases. Eur J Med Genet 2019; 62:103725. [DOI: 10.1016/j.ejmg.2019.103725] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Revised: 07/01/2019] [Accepted: 07/13/2019] [Indexed: 02/03/2023]
|
27
|
Uday S, Matsumura T, Saraff V, Saito S, Orimo H, Högler W. Tissue non-specific alkaline phosphatase activity and mineralization capacity of bi-allelic mutations from severe perinatal and asymptomatic hypophosphatasia phenotypes: Results from an in vitro mutagenesis model. Bone 2019; 127:9-16. [PMID: 31146036 DOI: 10.1016/j.bone.2019.05.031] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2019] [Revised: 05/24/2019] [Accepted: 05/25/2019] [Indexed: 10/26/2022]
Abstract
BACKGROUND Hypophosphatasia (HPP) is an inherited metabolic bone disease characterized by reduced mineralization due to mutations in the tissue non-specific alkaline phosphatase (ALPL) gene. HPP is clinically variable with extensive allelic heterogeneity in the ALPL gene. We report the findings of in vitro functional studies following site-directed mutagenesis in bi-allelic mutations causing extreme clinical phenotypes; severe perinatal and asymptomatic HPP. AIMS Elucidate genotype-phenotype correlation using in vitro functional studies and 3 dimensional (3D) ALP modelling. METHODS Clinical, biochemical and radiological features were recorded in two children with extreme HPP phenotypes: Subject 1 (S1): Perinatal HPP with compound heterozygous mutations (c.110T>C; c.532T>C); Subject 2 (S2): asymptomatic with homozygous missense mutation (c.715G>T). Plasmids created for mutants 1 c.110T>C (L37P), 2 c.532T>C (Y178H) and 3 c.715G>T (D239Y) using in vitro mutagenesis were transfected into human osteosarcoma (U2OS) cells and compared to wildtype (WT) and mock cDNA. ALP activity was measured using enzyme kinetics with p-nitrophenylphosphate. Mineral deposition was evaluated photometrically with Alizarin Red S staining after culture with mineralization medium. Western blot analysis was performed to identify the mature type protein expression (80 kDa). Mutations were located on a 3D ALP model. Co-transfection was performed to identify dominant negative effect of the mutants. RESULTS Phenotype: S1, had typical perinatal HPP phenotype at birth; extremely under-mineralized bones and pulmonary hypoplasia. S2, diagnosed incidentally by laboratory tests at 4 years, had normal growth, development, dentition and radiology. All S2's siblings (3 homozygous, 1 heterozygous) were asymptomatic. All subjects had typical biochemical features of HPP (low ALP, high serum pyridoxal-5'-phosphate), except the heterozygous sibling (normal ALP). Functional assay: Mutants 1 and 2 demonstrated negligible ALP activity and mineralization was 7.9% and 9.3% of WT, respectively. Mutant 3 demonstrated about 50% ALP activity and 15.5% mineralization of WT. On Western blot analysis, mutants 1 and 2 were detected as faint bands indicating reduced expression and mutant 3 was expressed as mature form protein with 50% of WT expression. Mutant 1 was located near the Glycosylphosphatidylinositol anchor, 2 at the core structure of the ALP protein and 3 at the periphery of the protein structure. Co-transfection did not reveal a dominant negative effect in any of the mutants. CONCLUSION Our findings expand the current knowledge of functional effect of individual mutations and the importance of their location in the ALP structure.
Collapse
Affiliation(s)
- Suma Uday
- Department of Endocrinology and Diabetes, Birmingham Women's and Children's Hospital, Birmingham, UK; Institute of Metabolism and Systems Research, University of Birmingham, Birmingham, UK
| | - Tomohiro Matsumura
- Department of Biochemistry and Molecular Biology, Graduate School of Medicine, Nippon Medical School, Tokyo, Japan
| | - Vrinda Saraff
- Department of Endocrinology and Diabetes, Birmingham Women's and Children's Hospital, Birmingham, UK
| | - Shiho Saito
- Department of Biochemistry and Molecular Biology, Graduate School of Medicine, Nippon Medical School, Tokyo, Japan
| | - Hideo Orimo
- Department of Biochemistry and Molecular Biology, Graduate School of Medicine, Nippon Medical School, Tokyo, Japan
| | - Wolfgang Högler
- Institute of Metabolism and Systems Research, University of Birmingham, Birmingham, UK; Department of Paediatrics and Adolescent Medicine, Johannes Kepler University, Linz, Austria.
| |
Collapse
|
28
|
Martins L, de Almeida AB, Dos Santos EJL, Foster BL, Machado RA, Kantovitz KR, Coletta RD, Nociti FH. A novel combination of biallelic ALPL mutations associated with adult hypophosphatasia: A phenotype-genotype association and computational analysis study. Bone 2019; 125:128-139. [PMID: 31077853 DOI: 10.1016/j.bone.2019.05.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 04/28/2019] [Accepted: 05/07/2019] [Indexed: 02/07/2023]
Abstract
Hypophosphatasia (HPP) is an inherited metabolic disorder that causes defective skeletal and dental mineralization. HPP exhibits a markedly heterogeneous range of clinical manifestations caused by dysfunction of the tissue-nonspecific isozyme of alkaline phosphatase (TNSALP), resulting from loss-of-function mutations in the ALPL gene. HPP has been associated with predominantly missense mutations in ALPL, and a number of compound heterozygous genotypes have been identified. Here, we describe a case of a subject with adult-onset HPP caused by a novel combination of missense mutations p.Gly473Ser and p.Ala487Val, resulting in chronic musculoskeletal pain, myopathy, persistent fatigue, vomiting, and an uncommon dental phenotype of short-rooted permanent teeth. Pedigree and biochemical analysis indicated that severity of symptoms was correlated with levels of residual ALP activity, and co-segregated with the p.Gly473Ser missense mutation. Bioinformatic analysis to predict the structural and functional impact of each of the point mutations in the TNSALP molecule, and its potential contribution to the clinical symptoms, revealed that the affected Gly473 residue is localized in the homodimer interface and predicted to have a dominant negative effect. The affected Ala487 residue was predicted to bind to Tyr479, which is closely located the N-terminal α-helix of TNSALP monomer 2, suggesting that both changes may impair dimer stability and catalytic functions. In conclusion, these findings assist in defining genotype-phenotype associations for HPP, and further define specific sites within the TNSALP molecule potentially related to neuromuscular manifestations in adult HPP, allowing for a better understanding of HPP pathophysiology.
Collapse
Affiliation(s)
- Luciane Martins
- Department of Prosthodontics and Periodontics, Division of Periodontics, Piracicaba Dental School, University of Campinas - UNICAMP, Piracicaba, SP, Brazil
| | - Amanda Bandeira de Almeida
- Department of Prosthodontics and Periodontics, Division of Periodontics, Piracicaba Dental School, University of Campinas - UNICAMP, Piracicaba, SP, Brazil
| | - Elis Janaína Lira Dos Santos
- Department of Prosthodontics and Periodontics, Division of Periodontics, Piracicaba Dental School, University of Campinas - UNICAMP, Piracicaba, SP, Brazil
| | - Brian L Foster
- Division of Biosciences, College of Dentistry, The Ohio State University, Columbus, OH, USA
| | - Renato Assis Machado
- Department of Oral Diagnosis, Piracicaba Dental School, University of Campinas - UNICAMP, Piracicaba, SP, Brazil
| | - Kamila Rosamilia Kantovitz
- Department of Pediatric Dentistry, Piracicaba Dental School, University of Campinas - UNICAMP, Piracicaba, SP, Brazil; Department of Dental Materials, São Leopoldo Mandic School of Dentistry and Research Center, Campinas, SP, Brazil
| | - Ricardo D Coletta
- Department of Oral Diagnosis, Piracicaba Dental School, University of Campinas - UNICAMP, Piracicaba, SP, Brazil
| | - Francisco H Nociti
- Department of Prosthodontics and Periodontics, Division of Periodontics, Piracicaba Dental School, University of Campinas - UNICAMP, Piracicaba, SP, Brazil.
| |
Collapse
|
29
|
Colazo JM, Hu JR, Dahir KM, Simmons JH. Neurological symptoms in Hypophosphatasia. Osteoporos Int 2019; 30:469-480. [PMID: 30215116 DOI: 10.1007/s00198-018-4691-6] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Accepted: 08/26/2018] [Indexed: 12/27/2022]
Abstract
UNLABELLED Hypophosphatasia (HPP) typically manifests with fractures, tooth loss, and muscle pain. Although mental health diagnoses and neurological symptoms have not been previously well documented in HPP, they occur commonly. The recognition of non-traditional symptoms may improve patient satisfaction, preempt costly evaluation and misdiagnosis, and lead to further treatment options. INTRODUCTION Hypophosphatasia (HPP) is an inborn error of metabolism due to deficiency of tissue non-specific alkaline phosphatase (TNSALP). It is traditionally characterized by rickets in children and osteomalacia in adults, along with fractures, tooth loss, and muscle pain. Neurological symptoms and mental health diagnoses have not been widely reported, and we therefore report their prevalence in a cohort of patients with HPP. METHODS A retrospective chart review was performed on a series of 82 HPP patients. Patient charts were reviewed to identify the possible presence and onset of 13 common neurological symptoms. RESULTS Median age was 36 years (2 to 79). Seventeen had adult onset HPP (> 18 years) and 65 had pediatric onset HPP (< 18 years). Median time from symptom onset to HPP diagnosis was 8 years (0 to 67). Seventy-four percent had a family history of bone disease, while 17% had a family history of neurologic disease. Bone problems occurred in 89%, dental problems in 77%, and muscle problems in 66%. Fatigue occurred in 66%, headache in 61%, sleep disturbance in 51%, gait change in 44%, vertigo in 43%, depression in 39%, anxiety in 35%, neuropathy in 35%, and hearing loss in 33%. CONCLUSIONS The extra-skeletal manifestations of HPP, specifically neurological symptoms, have not been previously well documented. However, mental health diagnoses and neurological symptoms such as headache and sleep disturbance occur commonly in patients with HPP. The recognition of non-traditional symptoms in HPP may improve patient satisfaction, preempt costly evaluation and misdiagnosis, and may lead to further treatment options.
Collapse
Affiliation(s)
- J M Colazo
- Vanderbilt University School of Medicine, Vanderbilt University Medical Center, Nashville, TN, 37232, USA
- Medical Scientist Training Program, Vanderbilt University School of Medicine, Nashville, TN, 37232, USA
| | - J R Hu
- Vanderbilt University School of Medicine, Vanderbilt University Medical Center, Nashville, TN, 37232, USA
| | - K M Dahir
- Department of Medicine, Division of Diabetes, Endocrinology, and Metabolism, Vanderbilt University Medical Center, Nashville, TN, 37232, USA
| | - J H Simmons
- Department of Pediatrics, Division of Diabetes, Endocrinology, and Metabolism, Vanderbilt University Medical Center, Nashville, TN, 37232, USA.
| |
Collapse
|
30
|
Offiah AC, Vockley J, Munns CF, Murotsuki J. Differential diagnosis of perinatal hypophosphatasia: radiologic perspectives. Pediatr Radiol 2019; 49:3-22. [PMID: 30284005 PMCID: PMC6313373 DOI: 10.1007/s00247-018-4239-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Revised: 06/25/2018] [Accepted: 08/14/2018] [Indexed: 01/13/2023]
Abstract
Perinatal hypophosphatasia (HPP) is a rare, potentially life-threatening, inherited, systemic metabolic bone disease that can be difficult to recognize in utero and postnatally. Diagnosis is challenging because of the large number of skeletal dysplasias with overlapping clinical features. This review focuses on the role of fetal and neonatal imaging modalities in the differential diagnosis of perinatal HPP from other skeletal dysplasias (e.g., osteogenesis imperfecta, campomelic dysplasia, achondrogenesis subtypes, hypochondrogenesis, cleidocranial dysplasia). Perinatal HPP is associated with a broad spectrum of imaging findings that are characteristic of but do not occur in all cases of HPP and are not unique to HPP, such as shortening, bowing and angulation of the long bones, and slender, poorly ossified ribs and metaphyseal lucencies. Conversely, absent ossification of whole bones is characteristic of severe lethal HPP and is associated with very few other conditions. Certain features may help distinguish HPP from other skeletal dysplasias, such as sites of angulation of long bones, patterns of hypomineralization, and metaphyseal characteristics. In utero recognition of HPP allows for the assembly and preparation of a multidisciplinary care team before delivery and provides additional time to devise treatment strategies.
Collapse
Affiliation(s)
- Amaka C Offiah
- Academic Unit of Child Health, Sheffield Children's NHS Foundation Trust, University of Sheffield, Western Bank, Sheffield, S10 2TH, UK.
| | - Jerry Vockley
- School of Medicine and Children's Hospital of Pittsburgh, University of Pittsburgh, Pittsburgh, PA, USA
| | - Craig F Munns
- The Children's Hospital at Westmead, Westmead, NSW, Australia
- Sydney Medical School, The University of Sydney, University of Sydney NSW, Sydney, Australia
| | - Jun Murotsuki
- Aoba Ward, Miyagi Children's Hospital, Sendai, Miyagi Prefecture, Japan
| |
Collapse
|
31
|
Taillandier A, Domingues C, Dufour A, Debiais F, Guggenbuhl P, Roux C, Cormier C, Cortet B, Porquet-Bordes V, Coury F, Geneviève D, Chiesa J, Colin T, Fletcher E, Guichet A, Javier RM, Laroche M, Laurent M, Lausch E, LeHeup B, Lukas C, Schwabe G, van der Burgt I, Muti C, Simon-Bouy B, Mornet E. Genetic analysis of adults heterozygous for ALPL mutations. J Bone Miner Metab 2018; 36:723-733. [PMID: 29236161 DOI: 10.1007/s00774-017-0888-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Accepted: 11/11/2017] [Indexed: 12/11/2022]
Abstract
Hypophosphatasia (HPP) is a rare inherited metabolic bone disease due to a deficiency of the tissue nonspecific alkaline phosphatase isoenzyme (TNSALP) encoded by the ALPL gene. Patients have consistently low serum alkaline phosphatase (AP), so that this parameter is a good hallmark of the disease. Adult HPP is heterogeneous, and some patients present only mild nonpathognomonic symptoms which are also common in the general population such as joint pain, osteomalacia and osteopenia, chondrocalcinosis, arthropathy and musculoskeletal pain. Adult HPP may be recessively or dominantly inherited; the latter case is assumed to be due to the dominant negative effect (DNE) of missense mutations derived from the functional homodimeric structure of TNSALP. However, there is no biological argument excluding the possibility of other causes of dominant HPP. Rheumatologists and endocrinologists are increasingly solicited for patients with low AP and nonpathognomonic symptoms of HPP. Many of these patients are heterozygous for an ALPL mutation and a challenging question is to determine if these symptoms, which are also common in the general population, are attributable to their heterozygous ALPL mutation or not. In an attempt to address this question, we reviewed a cohort of 61 adult patients heterozygous for an ALPL mutation. Mutations were distinguished according to their statistical likelihood to show a DNE. One-half of the patients carried mutations predicted with no DNE and were slightly less severely affected by the age of onset, serum AP activity and history of fractures. We hypothesized that these mutations result in another mechanism of dominance or are recessive alleles. To identify other genetic factors that could trigger the disease phenotype in heterozygotes for potential recessive mutations, we examined the next-generation sequencing results of 32 of these patients for a panel of 12 genes involved in the differential diagnosis of HPP or candidate modifier genes of HPP. The heterozygous genotype G/C of the COL1A2 coding SNP rs42524 c.1645C > G (p.Pro549Ala) was associated with the severity of the phenotype in patients carrying mutations with a DNE whereas the homozygous genotype G/G was over-represented in patients carrying mutations without a DNE, suggesting a possible role of this variant in the disease phenotype. These preliminary results support COL1A2 as a modifier gene of HPP and suggest that a significant proportion of adult heterozygotes for ALPL mutations may have unspecific symptoms not attributable to their heterozygosity.
Collapse
Affiliation(s)
- Agnès Taillandier
- Unité de Génétique Constitutionnelle, Service de Biologie, Centre Hospitalier de Versailles, 177 rue de Versailles, 78150, Le Chesnay, France
| | - Christelle Domingues
- Unité de Génétique Constitutionnelle, Service de Biologie, Centre Hospitalier de Versailles, 177 rue de Versailles, 78150, Le Chesnay, France
| | - Annika Dufour
- Unité de Génétique Constitutionnelle, Service de Biologie, Centre Hospitalier de Versailles, 177 rue de Versailles, 78150, Le Chesnay, France
| | - Françoise Debiais
- Service de Rhumatologie, CHU de Poitiers, 86021, Poitiers cedex, France
| | - Pascal Guggenbuhl
- Service de Rhumatologie, hôpital Sud, CHU de Rennes, 16, boulevard de Bulgarie, BP90347, 35203, Rennes cedex 2, France
| | | | | | | | - Valérie Porquet-Bordes
- Endocrinologie, Maladies Osseuses, Génétique et Gynécologie Médicale, Hôpital des Enfants, CHU de Toulouse, Toulouse Cedex 9, France
| | - Fabienne Coury
- Service de Rhumatologie, CHU Lyon, Centre Hospitalier Lyon-Sud, Pierre Bénite, France
| | - David Geneviève
- Service de Génétique Clinique, Département de Génétique Médicale, maladies rares et médecine personnalisée, CHU Montpellier, université Montpellier, unité Inserm U1183, Montpellier, France
| | - Jean Chiesa
- Department of Genetics, University Hospital, Nîmes, France
| | - Thierry Colin
- Service de Rhumatologie, CH Public du Cotentin, Cherbourg, France
| | - Elaine Fletcher
- Clinical Genetics, Molecular Medicine Center, Western General Hospital, Edinburgh, UK
| | - Agnès Guichet
- Département Biochimie et génétique, CHU d'Angers, Angers, France
| | | | - Michel Laroche
- Service de Rhumatologie, Hôpital Pierre-Paul Riquet, Toulouse, France
| | - Michael Laurent
- Center for Metabolic Bone Diseases, University Hospitals Leuven, Leuven, Belgium
| | - Ekkehart Lausch
- Universitätsklinikum Freiburg, Zentrum für Kinder- und Jugendmedizin, Freiburg, Germany
| | - Bruno LeHeup
- Médecine infantile 3, CHU Nancy, Vandoeuvre, France
| | - Cédric Lukas
- Département de Rhumatologie, CHRU Montpellier, Montpellier, France
| | - Georg Schwabe
- Otto-Heubner-Centrum für Kinder und Jugendmedizin Allgemeine Päediatrie Charité, Campus Virchow Klinikum Augustenburger Platz 1, Berlin, Germany
| | | | - Christine Muti
- Unité de Génétique Constitutionnelle, Service de Biologie, Centre Hospitalier de Versailles, 177 rue de Versailles, 78150, Le Chesnay, France
| | - Brigitte Simon-Bouy
- Unité de Génétique Constitutionnelle, Service de Biologie, Centre Hospitalier de Versailles, 177 rue de Versailles, 78150, Le Chesnay, France
| | - Etienne Mornet
- Unité de Génétique Constitutionnelle, Service de Biologie, Centre Hospitalier de Versailles, 177 rue de Versailles, 78150, Le Chesnay, France.
| |
Collapse
|
32
|
Abstract
Hypophosphatasia (HPP) is a rare inherited disorder primarily affecting bone and dental mineralization. Although there is a continuum in the severity of the disease, clinical forms may be arbitrarily distinguished on the basis of age at onset and the presence or absence of bone symptoms: perinatal, infantile, juvenile, adult, prenatal benign, and odontological. Severe forms (perinatal and infantile) are autosomally recessively inherited while less severe forms may be autosomally recessively or dominantly inherited. Genetic counseling is complicated by the coexistence of the two modes of inheritance, the incomplete penetrance of the dominant forms, the markedly variable expression of the disease, including intra-familial expression, and the existence of a benign prenatal form that may sometimes be difficult to distinguish from the severe prenatal form. The disease is due to loss-of-function mutations in the Alkaline Phosphatase-Liver (ALPL) gene encoding the tissue nonspecific alkaline phosphatase (TNSALP). The great variety of missence mutations and the dominant negative effect of some mutations largely explain the clinical heterogeneity. Directed mutagenesis studies allowed further elucidation of the cellular pathophysiology of HPP, classification of the alleles in terms of their severity and dominant negative effect, and molecular explanations of the dominant inheritance mode. Genetics significantly contributed to show that there are in fact two HPPs, rare, severe and recessive HPP, and mild recessive or mild dominant HPP, which is markedly more frequent and probably under-diagnosed. The prevalence of the severe forms of HPP has been estimated to be 1/300,000 in France and Northern Europe while the prevalence of the moderate forms of HPP may reach 1/6,370.
Collapse
Affiliation(s)
- E Mornet
- Service de biologie, unité de génétique constitutionnelle, centre hospitalier de Versailles, Le Chesnay, France.
| |
Collapse
|
33
|
Abstract
A genetic disorder should be suspected in patients with hypercalcemia, notably those who are young; have family members with hypercalcemia; or have had a tumor of the endocrine pancreas, thyroid, pituitary, adrenal gland, or jaw bone. All forms of hypercalcemia should be interpreted according to the serum level of parathyroid hormone (PTH). Genetic forms are thus classified as related or unrelated to a parathyroid gland disorder. When the PTH level is elevated or is not depressed despite the hypercalcemia, findings that suggest family history of hypercalcemia due to a genetic cause include syndromic manifestations in the patient or family members, parathyroid cancer (either suspected before surgery or confirmed during parathyroidectomy), multiple or recurrent parathyroid tumors, a family history of primary hyperparathyroidism, and the onset of primary hyperthyroidism before 50 years of age. In patients with moderate hypercalcemia, a normal PTH level, and relative hypocalciuria, the first hypothesis is a mutation in the calcium-sensing receptor gene, which is often difficult to distinguish from primary hyperparathyroidism, particularly when there is no known family history of hyperparathyroidism, as is often the case. A low PTH level suggests non-parathyroid hypercalcemia due to a genetic defect in patients with no evidence of other conditions associated with hypercalcemia and low PTH levels and in those whose calcitriol levels are elevated or normal (instead of depressed as expected when PTH is elevated). Patients with hypercalciuria but no evidence of conditions such as granulomatous diseases should be evaluated for increased vitamin D sensitivity due to a CYP 4A1 mutation. Other very rare causes include hypophosphatasia due to ALPL mutations, which is characterized by a low alkaline phosphatase level; and renal phosphate wasting due to an NPT2A mutation, in which serum phosphate levels are low. A thorough analysis of the clinical and laboratory data can point toward a genetic disorder in patients with hypercalcemia. The diagnosis is then confirmed by obtaining genetic tests tailored to the clinical and laboratory test abnormalities. The current development of diagnostic genetic testing is shedding new light on the phenotypes, thereby improving their management.
Collapse
Affiliation(s)
- Catherine Cormier
- Hôpital Cochin assistance publique, hôpitaux de Paris, 27, rue du faubourg Saint-Jacques, 75014 Paris, France.
| |
Collapse
|
34
|
Four novel mutations in the ALPL gene in Chinese patients with odonto, childhood, and adult hypophosphatasia. Biosci Rep 2018; 38:BSR20171377. [PMID: 29724887 PMCID: PMC6131208 DOI: 10.1042/bsr20171377] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Revised: 04/20/2018] [Accepted: 05/03/2018] [Indexed: 01/17/2023] Open
Abstract
Hypophosphatasia (HPP) is a rare inherited disorder characterized by defective bone and/or dental mineralization, and decreased serum alkaline phosphatase (ALP) activity. ALPL, the only gene related with HPP, encodes tissue non-specific ALP (TNSALP). Few studies were carried out in ALPL gene mutations in the Chinese population with HPP. The purpose of the present study is to elucidate the clinical and genetic characteristics of HPP in five unrelated Chinese families and two sporadic patients. Ten clinically diagnosed HPP patients from five unrelated Chinese families and two sporadic patients and fifty healthy controls were genetically investigated. All 12 exons and exon–intron boundaries of the ALPL gene were amplified by PCR and directly sequenced. The laboratory and radiological investigations were conducted simultaneously in these HPP ten patients. A 3D model of the TNSALP was used to predict the dominant negative effect of identified missense mutations. Three odonto, three childhood, and four adult types of HPP were clinically diagnosed. Ten mutations were identified in five unrelated Chinese families and two sporadic patients, including eight missense mutations and two frameshift mutations. Of which, four were novel: one frameshift mutation (p.R138Pfsx45); three missense mutations (p.C201R, p.V459A, p.C497S). No identical mutations and any other new ALPL mutations were found in unrelated 50 healthy controls. Our study demonstrated that the ALPL gene mutations are responsible for HPP in these Chinese families. These findings will be useful for clinicians to improve understanding of this heritable bone disorder.
Collapse
|
35
|
Dahir KM, Tilden DR, Warner JL, Bastarache L, Smith DK, Gifford A, Ramirez AH, Simmons JS, Black MM, Newman JH, Denny JC. Rare Variants in the Gene ALPL That Cause Hypophosphatasia Are Strongly Associated With Ovarian and Uterine Disorders. J Clin Endocrinol Metab 2018; 103:2234-2243. [PMID: 29659871 PMCID: PMC6456921 DOI: 10.1210/jc.2017-02676] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Accepted: 04/02/2018] [Indexed: 11/19/2022]
Abstract
CONTEXT Mutations in alkaline phosphatase (AlkP), liver/bone/kidney (ALPL), which encodes tissue-nonspecific isozyme AlkP, cause hypophosphatasia (HPP). HPP is suspected by a low-serum AlkP. We hypothesized that some patients with bone or dental disease have undiagnosed HPP, caused by ALPL variants. OBJECTIVE Our objective was to discover the prevalence of these gene variants in the Vanderbilt University DNA Biobank (BioVU) and to assess phenotypic associations. DESIGN We identified subjects in BioVU, a repository of DNA, that had at least one of three known, rare HPP disease-causing variants in ALPL: rs199669988, rs121918007, and/or rs121918002. To evaluate for phenotypic associations, we conducted a sequential phenome-wide association study of ALPL variants and then performed a de-identified manual record review to refine the phenotype. RESULTS Out of 25,822 genotyped individuals, we identified 52 women and 53 men with HPP disease-causing variants in ALPL, 7/1000. None had a clinical diagnosis of HPP. For patients with ALPL variants, the average serum AlkP levels were in the lower range of normal or lower. Forty percent of men and 62% of women had documented bone and/or dental disease, compatible with the diagnosis of HPP. Forty percent of the female patients had ovarian pathology or other gynecological abnormalities compared with 15% seen in controls. CONCLUSIONS Variants in the ALPL gene cause bone and dental disease in patients with and without the standard biomarker, low plasma AlkP. ALPL gene variants are more prevalent than currently reported and underdiagnosed. Gynecologic disease appears to be associated with HPP-causing variants in ALPL.
Collapse
Affiliation(s)
- Kathryn M Dahir
- Division of Endocrinology, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
- Correspondence and Reprint Requests: Kathryn M. Dahir, MD, 21st Avenue South, Medical Center East 8210, Nashville, Tennessee 37232-8148. E-mail:
| | - Daniel R Tilden
- Department of Internal Medicine and Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Jeremy L Warner
- Division of Hematology and Oncology, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
- Department of Biomedical Informatics, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Lisa Bastarache
- Department of Biomedical Informatics, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Derek K Smith
- Departments of Biostatistics and Oral Maxillofacial Surgery, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Aliya Gifford
- Department of Biomedical Informatics, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Andrea H Ramirez
- Division of Endocrinology, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Jill S Simmons
- Division of Pediatric Endocrinology, Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Margo M Black
- Division of Pediatric Endocrinology, Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee
| | - John H Newman
- Division of Allergy, Pulmonary and Critical Care Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Josh C Denny
- Department of Biomedical Informatics, Vanderbilt University Medical Center, Nashville, Tennessee
- Division of General Internal Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
| |
Collapse
|
36
|
Abstract
We review here clinical, pathophysiological, diagnostic, genetic and molecular aspects of Hypophosphatasia (HPP), a rare inherited metabolic disorder. The clinical presentation is a continuum ranging from a prenatal lethal form with no skeletal mineralization to a mild form with late adult onset presenting with nonpathognomonic symptoms. The prevalence of severe forms is low, whereas less severe forms are more frequently observed. The disease is caused by loss-of-function mutations in the ALPL gene encoding the Tissue Nonspecific Alkaline Phosphatase (TNSALP), a central regulator of mineralization. Severe forms are recessively inherited, whereas moderate forms are either recessively or dominantly inherited, and the more severe the disease is, the more often it is subject to recessive inheritance. The diagnosis is based on a constantly low alkaline phosphatase (AP) activity in serum and genetic testing that identifies ALPL mutations. More than 340 mutations have been identified and are responsible for the extraordinary clinical heterogeneity. A clear but imperfect genotype-phenotype correlation has been observed, suggesting that other genetic or environmental factors modulate the phenotype. Enzyme replacement therapy is now available for HPP, and other approaches, such as gene therapy, are currently being investigated.
Collapse
Affiliation(s)
- Etienne Mornet
- Unité de Génétique Constitutionnelle, Service de Biologie, Centre Hospitalier de Versailles, 177 rue de Versailles, 78150 Le Chesnay, France.
| |
Collapse
|
37
|
Kishnani PS, Rush ET, Arundel P, Bishop N, Dahir K, Fraser W, Harmatz P, Linglart A, Munns CF, Nunes ME, Saal HM, Seefried L, Ozono K. Monitoring guidance for patients with hypophosphatasia treated with asfotase alfa. Mol Genet Metab 2017; 122:4-17. [PMID: 28888853 DOI: 10.1016/j.ymgme.2017.07.010] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Revised: 07/20/2017] [Accepted: 07/24/2017] [Indexed: 11/15/2022]
Abstract
Hypophosphatasia (HPP) is a rare, inherited, systemic, metabolic disorder caused by autosomal recessive mutations or a single dominant-negative mutation in the gene encoding tissue-nonspecific alkaline phosphatase (TNSALP). The disease is associated with a broad range of signs, symptoms, and complications, including impaired skeletal mineralization, altered calcium and phosphate metabolism, recurrent fractures, pain, respiratory problems, impaired growth and mobility, premature tooth loss, developmental delay, and seizures. Asfotase alfa is a human, recombinant enzyme replacement therapy that is approved in many countries for the treatment of patients with HPP. To address the unmet need for guidance in the monitoring of patients receiving asfotase alfa, an international panel of physicians with experience in diagnosing and managing HPP convened in May 2016 to discuss treatment monitoring parameters. The panel discussions focused on recommendations for assessing and monitoring patients after the decision to treat with asfotase alfa had been made and did not include recommendations for whom to treat. Based on the consensus of panel members, this review provides guidance on the monitoring of patients with HPP during treatment with asfotase alfa, including recommendations for laboratory, efficacy, and safety assessments and the frequency with which these should be performed during the course of treatment. Recommended assessments are based on patient age and include regular monitoring of biochemistry, skeletal radiographs, respiratory function, growth, pain, mobility and motor function, and quality of life. Because of the systemic presentation of HPP, a coordinated, multidisciplinary, team-based, patient-focused approach is recommended in the management of patients receiving asfotase alfa. Monitoring of efficacy and safety outcomes must be tailored to the individual patient, depending on medical history, clinical manifestations, availability of resources in the clinical setting, and the clinician's professional judgment.
Collapse
Affiliation(s)
- Priya S Kishnani
- Division of Medical Genetics, Duke University Medical Center, Durham, NC 27710, USA.
| | - Eric T Rush
- Department of Pediatrics, University of Nebraska Medical Center, Omaha, NE 68198, USA(2)
| | - Paul Arundel
- Metabolic Bone Team, Sheffield Children's NHS Foundation Trust, Sheffield S10 2TH, UK
| | - Nick Bishop
- Academic Unit of Child Health, University of Sheffield and Sheffield Children's Hospital, Sheffield S10 2TH, UK
| | - Kathryn Dahir
- Division of Diabetes and Endocrinology, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - William Fraser
- Norwich Medical School, Faculty of Medicine and Health Sciences, University of East Anglia, Norwich NR4 7UY, UK
| | - Paul Harmatz
- Pediatric Gastroenterology and Nutrition, UCSF Benioff Children's Hospital Oakland, Oakland, CA 94609, USA
| | - Agnès Linglart
- Service d'Endocrinologie Pédiatrique, Hôpital Bicêtre Paris-Sud, APHP, 94270 Le Kremlin Bicêtre, France
| | - Craig F Munns
- Paediatrics & Child Health, The Children's Hospital at Westmead, Westmead, NSW 2145, Australia; Sydney Medical School, University of Sydney, Sydney, NSW 2006, Australia
| | - Mark E Nunes
- Department of Pediatrics, University of California, San Diego, San Diego, CA 92093, USA
| | - Howard M Saal
- Division of Human Genetics, Cincinnati Children's Hospital, Cincinnati, OH 45229, USA
| | - Lothar Seefried
- Orthopedic Department, University of Würzburg, Würzburg, Bavaria 97074, Germany
| | - Keiichi Ozono
- Department of Pediatrics, Osaka University, Suita, Osaka 565-0871, Japan
| |
Collapse
|
38
|
Porntaveetus T, Srichomthong C, Suphapeetiporn K, Shotelersuk V. Monoallelic FGFR3
and Biallelic ALPL
mutations in a Thai girl with hypochondroplasia and hypophosphatasia. Am J Med Genet A 2017; 173:2747-2752. [DOI: 10.1002/ajmg.a.38370] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 06/16/2017] [Accepted: 06/25/2017] [Indexed: 01/22/2023]
Affiliation(s)
- Thantrira Porntaveetus
- Craniofacial Genetics and Stem Cells Research Group, Faculty of Dentistry, Department of Physiology; Chulalongkorn University; Bangkok Thailand
| | - Chalurmpon Srichomthong
- Center of Excellence for Medical Genetics, Faculty of Medicine, Department of Pediatrics; Chulalongkorn University; Bangkok Thailand
- Excellence Center for Medical Genetics, King Chulalongkorn Memorial Hospital; The Thai Red Cross Society; Bangkok Thailand
| | - Kanya Suphapeetiporn
- Center of Excellence for Medical Genetics, Faculty of Medicine, Department of Pediatrics; Chulalongkorn University; Bangkok Thailand
- Excellence Center for Medical Genetics, King Chulalongkorn Memorial Hospital; The Thai Red Cross Society; Bangkok Thailand
| | - Vorasuk Shotelersuk
- Center of Excellence for Medical Genetics, Faculty of Medicine, Department of Pediatrics; Chulalongkorn University; Bangkok Thailand
- Excellence Center for Medical Genetics, King Chulalongkorn Memorial Hospital; The Thai Red Cross Society; Bangkok Thailand
| |
Collapse
|
39
|
Kitaoka T, Tajima T, Nagasaki K, Kikuchi T, Yamamoto K, Michigami T, Okada S, Fujiwara I, Kokaji M, Mochizuki H, Ogata T, Tatebayashi K, Watanabe A, Yatsuga S, Kubota T, Ozono K. Safety and efficacy of treatment with asfotase alfa in patients with hypophosphatasia: Results from a Japanese clinical trial. Clin Endocrinol (Oxf) 2017; 87:10-19. [PMID: 28374482 DOI: 10.1111/cen.13343] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
OBJECTIVE Hypophosphatasia (HPP) is a rare skeletal disease characterized by hypomineralization and low alkaline phosphatase activity. Asfotase alfa (AA) has been recently developed to treat HPP complications. This study evaluated its safety and efficacy in Japan. DESIGN Open-label, multicentre, prospective trial. Patients were enrolled in 11 hospitals from June 2014 to July 2015. PATIENTS Thirteen patients (9 females, 4 males) ages 0 days to 34 years at baseline were enrolled and treated with AA (2 mg/kg three times weekly subcutaneously in all but one patient). All had ALPL gene mutations. HPP forms were perinatal (n=6), infantile (n=5), childhood (n=1) and adult (n=1). MEASUREMENTS Safety determined from adverse events (AEs) and laboratory data was the primary outcome measure. Efficacy was assessed as a secondary outcome measure from overall survival, respiratory status, rickets severity and gross motor development. RESULTS Injection site reactions were the most frequent AEs. Serious AEs possibly related to treatment were convulsion and hypocalcaemia observed in a patient with the perinatal form. In addition, hypercalcaemia and/or hyperphosphatemia was observed in three patients with the infantile form and a low-calcium and/or low-phosphate formula was given to these patients. With respect to efficacy, all patients survived and the radiographic findings, developmental milestones and respiratory function improved. CONCLUSION Asfotase alfa therapy improved skeletal, respiratory and physical symptoms with a few serious AEs in patients with HPP. Our results add support to the safety and efficacy of AA therapy for HPP patients.
Collapse
Affiliation(s)
- Taichi Kitaoka
- Department of Pediatrics, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Toshihiro Tajima
- Department of Pediatrics, Hokkaido University School of Medicine, Sapporo, Japan
| | - Keisuke Nagasaki
- Division of Pediatrics, Department of Homeostatic Regulation and Development, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Toru Kikuchi
- Division of Pediatrics, Department of Homeostatic Regulation and Development, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Katsusuke Yamamoto
- Department of Pediatric Nephrology and Metabolism, Osaka Medical Center and Research Institute for Maternal and Child Health, Osaka, Japan
| | - Toshimi Michigami
- Department of Bone and Mineral Research, Osaka Medical Center and Research Institute for Maternal and Child Health, Osaka, Japan
| | - Satoshi Okada
- Department of Pediatrics, Hiroshima University Graduate School of Biomedical & Health Sciences, Hiroshima, Japan
| | - Ikuma Fujiwara
- Department of Pediatrics, Tohoku University School of Medicine, Miyagi, Japan
| | - Masayuki Kokaji
- Department of Pediatrics, Showa General Hospital, Tokyo, Japan
| | - Hiroshi Mochizuki
- Division of Endocrinology and Metabolism, Saitama Children's Medical Center, Saitama, Japan
| | - Tsutomu Ogata
- Department of Pediatrics, Hamamatsu University School of Medicine, Hamamatsu, Japan
| | | | - Atsushi Watanabe
- Division of Clinical Genetics, Nippon Medical School Hospital, Tokyo, Japan
| | - Shuichi Yatsuga
- Department of Pediatrics and Child Health, Kurume University School of Medicine, Fukuoka, Japan
| | - Takuo Kubota
- Department of Pediatrics, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Keiichi Ozono
- Department of Pediatrics, Osaka University Graduate School of Medicine, Osaka, Japan
| |
Collapse
|
40
|
|
41
|
Wu Y, Wang Y, Tao J, Han X, Zhao X, Liu C, Gao L, Cheng W. The clinical use of chromosomal microarray analysis in detection of fetal chromosomal rearrangements: a study from China Mainland. Eur J Obstet Gynecol Reprod Biol 2017; 212:44-50. [DOI: 10.1016/j.ejogrb.2017.03.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2016] [Revised: 02/19/2017] [Accepted: 03/04/2017] [Indexed: 10/20/2022]
|
42
|
Baujat G, Michot C, Le Quan Sang K, Cormier-Daire V. Perinatal and infantile hypophosphatasia: clinical features and treatment. Arch Pediatr 2017; 24:5S61-5S65. [DOI: 10.1016/s0929-693x(18)30016-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
43
|
Di Rocco F, Baujat G, Cormier-Daire V, Rothenbuhler A, Linglart A. Craniosynostosis and hypophosphatasia. Arch Pediatr 2017; 24:5S89-5S92. [DOI: 10.1016/s0929-693x(18)30022-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
|
44
|
Meah F, Basit A, Emanuele N, Emanuele MA. Hypophosphatasia: Review of Bone Mineral Metabolism, Pathophysiology, Clinical Presentation, Diagnosis, and Treatment. Clin Rev Bone Miner Metab 2017. [DOI: 10.1007/s12018-016-9225-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
|
45
|
Tenorio J, Álvarez I, Riancho-Zarrabeitia L, Martos-Moreno GÁ, Mandrile G, de la Flor Crespo M, Sukchev M, Sherif M, Kramer I, Darnaude-Ortiz MT, Arias P, Gordo G, Dapía I, Martinez-Villanueva J, Gómez R, Iturzaeta JM, Otaify G, García-Unzueta M, Rubinacci A, Riancho JA, Aglan M, Temtamy S, Hamid MA, Argente J, Ruiz-Pérez VL, Heath KE, Lapunzina P. Molecular and clinical analysis ofALPLin a cohort of patients with suspicion of Hypophosphatasia. Am J Med Genet A 2017; 173:601-610. [DOI: 10.1002/ajmg.a.37991] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Accepted: 09/18/2016] [Indexed: 11/11/2022]
Affiliation(s)
- Jair Tenorio
- Institute of Medical and Molecular Genetics (INGEMM); Hospital Universitario La Paz, IdiPAZ; Universidad Autónoma de Madrid; Madrid Spain
- CIBERER; Centro de Investigación Biomédica en Red de Enfermedades Raras, ISCIII; Madrid Spain
| | | | | | - Gabriel Á. Martos-Moreno
- Department of Endocrinology; Hospital Universitario Niño Jesús, IIS La Princesa; Madrid Spain
- Department of Pediatrics; Universidad Autónoma de Madrid; Madrid Spain
- CIBEROBN, Centro de Investigación Biomédica en Red sobre Fisiopatología de la obesidad y nutrición; Instituto de Salud Carlos III; Madrid Spain
| | - Giorgia Mandrile
- Department of Medical Genetics; San Luigi University Hospital; Orbassano Italy
- Department Clinical and Biological Sciences; University of Torino; Torino Italy
| | | | - Mikhail Sukchev
- Diagnostic Specialist; Alexion Pharmaceuticals; Moscow Russia
| | - Mostafa Sherif
- Medical Division; Alexion Pharma Middle East; Dubai Media City United Arab Emirates
| | - Iza Kramer
- Department of Pediatrics; Privat Hospitalet Denmark; Charlottenlund Denmark
| | | | - Pedro Arias
- Institute of Medical and Molecular Genetics (INGEMM); Hospital Universitario La Paz, IdiPAZ; Universidad Autónoma de Madrid; Madrid Spain
- CIBERER; Centro de Investigación Biomédica en Red de Enfermedades Raras, ISCIII; Madrid Spain
| | - Gema Gordo
- Institute of Medical and Molecular Genetics (INGEMM); Hospital Universitario La Paz, IdiPAZ; Universidad Autónoma de Madrid; Madrid Spain
- CIBERER; Centro de Investigación Biomédica en Red de Enfermedades Raras, ISCIII; Madrid Spain
| | - Irene Dapía
- Institute of Medical and Molecular Genetics (INGEMM); Hospital Universitario La Paz, IdiPAZ; Universidad Autónoma de Madrid; Madrid Spain
- CIBERER; Centro de Investigación Biomédica en Red de Enfermedades Raras, ISCIII; Madrid Spain
| | | | - Rubén Gómez
- Department of Biochemistry; Hospital Universitario La Paz, IdiPaz; Madrid Spain
| | | | - Ghada Otaify
- Division of Human Genetics and Genome Research; Department of Clinical Genetics; National Research Centre, Cairo; Egypt
- Centre of Excellence for Human Genetics; National Research Centre; Cairo Egypt
| | - Mayte García-Unzueta
- Department of Clinical Biochemistry; Hospital Universitario Marqués Valdecilla, IDIVAL; Santander Spain
| | | | - José A. Riancho
- Department of Internal Medicine; Hospital Universitario Marqués Valdecilla, IDIVAL; University of Cantabria, RETICEF; Santander Spain
| | - Mona Aglan
- Division of Human Genetics and Genome Research; Department of Clinical Genetics; National Research Centre, Cairo; Egypt
- Centre of Excellence for Human Genetics; National Research Centre; Cairo Egypt
| | - Samia Temtamy
- Division of Human Genetics and Genome Research; Department of Clinical Genetics; National Research Centre, Cairo; Egypt
- Centre of Excellence for Human Genetics; National Research Centre; Cairo Egypt
| | - Mohamed Abdel Hamid
- Centre of Excellence for Human Genetics; National Research Centre; Cairo Egypt
- Division of Human Genetics and Genome Research; Department of Medical Molecular Genetics; National Research Centre; El Cairo Egypt
| | - Jesús Argente
- Department of Endocrinology; Hospital Universitario Niño Jesús, IIS La Princesa; Madrid Spain
- Department of Pediatrics; Universidad Autónoma de Madrid; Madrid Spain
- CIBEROBN, Centro de Investigación Biomédica en Red sobre Fisiopatología de la obesidad y nutrición; Instituto de Salud Carlos III; Madrid Spain
| | - Víctor L. Ruiz-Pérez
- CIBERER; Centro de Investigación Biomédica en Red de Enfermedades Raras, ISCIII; Madrid Spain
- Skeletal Dysplasia Multidisciplinary Unit (UMDE); Hospital Universitario La Paz; Madrid Spain
- Instituto de Investigaciones Biológicas (IB); Consejo Superior de Investigaciones Científicas (CSIC)-Universidad Autónoma de Madrid; Madrid Spain
| | - Karen E. Heath
- Institute of Medical and Molecular Genetics (INGEMM); Hospital Universitario La Paz, IdiPAZ; Universidad Autónoma de Madrid; Madrid Spain
- CIBERER; Centro de Investigación Biomédica en Red de Enfermedades Raras, ISCIII; Madrid Spain
- Skeletal Dysplasia Multidisciplinary Unit (UMDE); Hospital Universitario La Paz; Madrid Spain
| | - Pablo Lapunzina
- Institute of Medical and Molecular Genetics (INGEMM); Hospital Universitario La Paz, IdiPAZ; Universidad Autónoma de Madrid; Madrid Spain
- CIBERER; Centro de Investigación Biomédica en Red de Enfermedades Raras, ISCIII; Madrid Spain
- Skeletal Dysplasia Multidisciplinary Unit (UMDE); Hospital Universitario La Paz; Madrid Spain
| |
Collapse
|
46
|
Funck-Brentano T, Ostertag A, Debiais F, Fardellone P, Collet C, Mornet E, Cohen-Solal M. Identification of a p.Arg708Gln variant in COL1A2 in atypical femoral fractures. Joint Bone Spine 2016; 84:715-718. [PMID: 28017821 DOI: 10.1016/j.jbspin.2016.11.014] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Accepted: 11/23/2016] [Indexed: 12/12/2022]
Abstract
OBJECTIVES Long-term bisphosphonates exposure is a proven risk factor for atypical femoral fractures (AFF) but several cases occur in untreated patients. The identification of other risk factors for AFF is critical for the management of osteoporosis. We here assessed the genetic factors associated with AFF regardless of the treatment. METHODS Cases were identified through ICD-10 codes in 3 academic centers. Medical records were analyzed by 2 investigators that adjudicated X-rays for typical or atypical fractures. Genetic screening for ALPL, SOX9, COL1A1 and COL1A2 variants was performed after patient's information and consent. RESULTS A total of 389 cases were identified and 268 were ruled out according to the ASBMR Task Force recommendations. On the remaining 121, 14 (11.6%) were AFF. Anti-osteoporotic drugs were more frequent in the AFF group compared to the typical fracture group (35% vs 5%, P<0.001) but only 4 (28.6%) patients with AFF had been exposed to bisphosphonates. Genetic analysis performed in 5 patients found one with a heterozygous mutation in COL1A2 (rs72658163, NM_000089.3:c.2123G>A, p.Arg708Gln). This rare variant (Minor Allele Frequency=0.0008) causes a missense mutation that alters collagen fibrillogenesis. Eight heterozygous polymorphisms for ALPL were also found in 3 patients. CONCLUSION Genetic screening for variants in only 4 genes and 5 patients with AFF resulted in the identification of genetic variants in 3 patients including a rare variant in COL1A2, suggesting a possible genetic susceptibility to AFF. This finding should encourage clinician to further genotype patients with AFF in a collaborative multicentric project.
Collapse
Affiliation(s)
- Thomas Funck-Brentano
- Inserm UMR1132, université Paris Diderot, Sorbonne Paris Cité, 2, rue Ambroise-Paré, 75010 Paris, France; Department of rheumatology, Lariboisière hospital, université Paris Diderot, 75010 Paris, France
| | - Agnes Ostertag
- Inserm UMR1132, université Paris Diderot, Sorbonne Paris Cité, 2, rue Ambroise-Paré, 75010 Paris, France
| | - Francoise Debiais
- Department of rheumatology, Poitiers university hospital, 86021 Poitiers, France
| | - Patrice Fardellone
- Department of rheumatology, Amiens university hospital, 8000 Amiens, France
| | - Corinne Collet
- Inserm UMR1132, université Paris Diderot, Sorbonne Paris Cité, 2, rue Ambroise-Paré, 75010 Paris, France
| | - Etienne Mornet
- Unité de génétique constitutionnelle, centre hospitalier de Versailles, 78150 Le Chesnay, France
| | - Martine Cohen-Solal
- Inserm UMR1132, université Paris Diderot, Sorbonne Paris Cité, 2, rue Ambroise-Paré, 75010 Paris, France; Department of rheumatology, Lariboisière hospital, université Paris Diderot, 75010 Paris, France.
| |
Collapse
|
47
|
Bloch-Zupan A. Hypophosphatasia: diagnosis and clinical signs - a dental surgeon perspective. Int J Paediatr Dent 2016; 26:426-438. [PMID: 27030892 DOI: 10.1111/ipd.12232] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
BACKGROUND Hypophosphatasia (HPP) is a rare inherited metabolic disease in which mutations in the ALPL gene (encoding tissue-nonspecific alkaline phosphatase) result in varying degrees of enzyme deficiency. HPP manifests in a spectrum of symptoms, including early primary tooth loss (root intact) and alveolar bone mineralisation defects. OBJECTIVE To provide an overview of HPP for dental professionals to help recognise and differentially diagnose patients for appropriate referral to a specialist team. METHODS A non-systematic review of publications on HPP was performed. RESULTS Different forms of HPP are described, along with characteristic symptoms and laboratory findings. Diagnosis is challenging due to the rareness and variable presentation of symptoms. Low alkaline phosphatase levels are a signature of HPP, but reference ranges vary according to gender and age. Key features are defined and management strategies discussed, focusing on enzyme replacement therapy. Finally, a patient registry aimed at better defining the prevalence of HPP and raising awareness is described. CONCLUSIONS HPP is a rare disease with a wide spectrum of manifestations, with orodental symptoms featuring prominently in the natural history. Dental professionals may be positioned at the beginning of the diagnostic pathway; thus, recognition of HPP features for timely referral and optimal disease management is important.
Collapse
Affiliation(s)
- Agnès Bloch-Zupan
- Faculté de Chirurgie Dentaire, Université de Strasbourg, Strasbourg, France. .,Hôpitaux Universitaires de Strasbourg, Pôle de Médecine et Chirurgie Bucco-Dentaires, Centre de référence des manifestations odontologiques des maladies rares (CRMR), Reference Centre for Orodental Manifestations of Rare Diseases, Strasbourg, France. .,Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), INSERM U964, CNRS-UdS UMR7104, Université de Strasbourg, Illkirch, France. .,Eastman Dental Institute, University College London, London, UK.
| |
Collapse
|
48
|
|
49
|
Belkhouribchia J, Bravenboer B, Meuwissen M, Velkeniers B. Osteomalacia with low alkaline phosphatase: a not so rare condition with important consequences. BMJ Case Rep 2016; 2016:bcr-2015-212827. [PMID: 26823351 DOI: 10.1136/bcr-2015-212827] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Hypophosphatasia is a genetic disorder, characterised by a dysfunctional tissue-non-specific isoenzyme of alkaline phosphatase that impacts bone metabolism and predisposes to osteomalacia or rickets. The clinical presentation is very diverse, depending on the age of onset and the severity of the disease. Several forms of hypophosphatasia are recognised. We present a case of a 50-year-old woman with low impact fractures and loss of teeth at a young age. She also had a low alkaline phosphatase and was diagnosed with adult hypophosphatasia. Although the severe forms of hypophosphatasia are rather rare, the adult form is thought to occur quite frequently. As this condition is not well known by healthcare professionals, the time to diagnosis and initiation of adequate treatment is often postponed. When encountering a patient with low alkaline phosphatase, low bone density or a history of bone fractures, the possibility of hypophosphatasia should be considered.
Collapse
Affiliation(s)
| | - Bert Bravenboer
- Department of Endocrinology, Universitair Ziekenhuis Brussel, Brussels, Belgium
| | - Marije Meuwissen
- Department of Genetics, Universitair Ziekenhuis Antwerpen, Edegem, Belgium
| | | |
Collapse
|