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Moritz L, Schumann A, Pohl M, Köttgen A, Hannibal L, Spiekerkoetter U. A systematic review of metabolomic findings in adult and pediatric renal disease. Clin Biochem 2024; 123:110703. [PMID: 38097032 DOI: 10.1016/j.clinbiochem.2023.110703] [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: 06/16/2023] [Revised: 12/03/2023] [Accepted: 12/07/2023] [Indexed: 12/29/2023]
Abstract
Chronic kidney disease (CKD) affects over 0.5 billion people worldwide across their lifetimes. Despite a growingly ageing world population, an increase in all-age prevalence of kidney disease persists. Adult-onset forms of kidney disease often result from lifestyle-modifiable metabolic illnesses such as type 2 diabetes. Pediatric and adolescent forms of renal disease are primarily caused by morphological abnormalities of the kidney, as well as immunological, infectious and inherited metabolic disorders. Alterations in energy metabolism are observed in CKD of varying causes, albeit the molecular mechanisms underlying pathology are unclear. A systematic indexing of metabolites identified in plasma and urine of patients with kidney disease alongside disease enrichment analysis uncovered inborn errors of metabolism as a framework that links features of adult and pediatric kidney disease. The relationship of genetics and metabolism in kidney disease could be classified into three distinct landscapes: (i) Normal genotypes that develop renal damage because of lifestyle and / or comorbidities; (ii) Heterozygous genetic variants and polymorphisms that result in unique metabotypes that may predispose to the development of kidney disease via synergistic heterozygosity, and (iii) Homozygous genetic variants that cause renal impairment by perturbing metabolism, as found in children with monogenic inborn errors of metabolism. Interest in the identification of early biomarkers of onset and progression of CKD has grown steadily in the last years, though it has not translated into clinical routine yet. This systematic review indexes findings of differential concentration of metabolites and energy pathway dysregulation in kidney disease and appraises their potential use as biomarkers.
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Affiliation(s)
- Lennart Moritz
- Laboratory of Clinical Biochemistry and Metabolism, Department of General Pediatrics, Adolescent Medicine and Neonatology, Faculty of Medicine, Medical Center, University of Freiburg, 79106 Freiburg, Germany; Department of General Pediatrics, Adolescent Medicine and Neonatology, Faculty of Medicine, Medical Center, University of Freiburg, 79106 Freiburg, Germany
| | - Anke Schumann
- Laboratory of Clinical Biochemistry and Metabolism, Department of General Pediatrics, Adolescent Medicine and Neonatology, Faculty of Medicine, Medical Center, University of Freiburg, 79106 Freiburg, Germany; Department of General Pediatrics, Adolescent Medicine and Neonatology, Faculty of Medicine, Medical Center, University of Freiburg, 79106 Freiburg, Germany
| | - Martin Pohl
- Department of General Pediatrics, Adolescent Medicine and Neonatology, Faculty of Medicine, Medical Center, University of Freiburg, 79106 Freiburg, Germany
| | - Anna Köttgen
- Institute of Genetic Epidemiology, Faculty of Medicine, Medical Center, University of Freiburg, 79106 Freiburg, Germany
| | - Luciana Hannibal
- Laboratory of Clinical Biochemistry and Metabolism, Department of General Pediatrics, Adolescent Medicine and Neonatology, Faculty of Medicine, Medical Center, University of Freiburg, 79106 Freiburg, Germany.
| | - Ute Spiekerkoetter
- Department of General Pediatrics, Adolescent Medicine and Neonatology, Faculty of Medicine, Medical Center, University of Freiburg, 79106 Freiburg, Germany.
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Douillard C, Arnoux JB, Bouée S, Jacob C, Schneider KM, Theil J, Charrière S, Maillot F. Health status and comorbidities of adult patients with late-diagnosed phenylketonuria (PKU) born before the newborn screening in France - A nationwide study of health insurance claims data. Mol Genet Metab 2023; 140:107704. [PMID: 37812967 DOI: 10.1016/j.ymgme.2023.107704] [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: 07/16/2023] [Revised: 09/25/2023] [Accepted: 09/28/2023] [Indexed: 10/11/2023]
Abstract
BACKGROUND Phenylketonuria (PKU) is an inborn error of metabolism. When diagnosed late, it causes developmental delay or severe irreversible intellectual disability. This study aimed at evaluating the health status and healthcare consumption of late-diagnosed PKU patients in France. METHODS This retrospective observational study used health insurance claims data from the French SNDS (Système National des Données de Santé) database, which contains data from over 66 million French inhabitants. Patients with PKU were identified between 2006 and 2018 by ICD-10 diagnosis codes E70.0 / E70.1 documented as a chronic condition (affection de longue durée - ALD) or in the inpatient setting. Patients with PKU were matched to controls by age, sex, and region. Patients with late-diagnosed PKU were defined as patients born before the nationwide implementation of newborn screening in France in 1972. Outcomes were analyzed for the year 2018. RESULTS In total, 3549 patients with PKU were identified in the database on January 1st, 2018. Of those, 3469 patients could be matched to 17,170 controls without PKU. Of these, 2175 patients were at least 16 years old of whom 647 patients were categorized as late-diagnosed. The late-diagnosed PKU patients suffered significantly more often from hypertension (60.9% vs. 50.4%, p < 0.0001), hypercholesterolemia (41.7% vs. 26.9%, p < 0.0001), diabetes (24.4% vs. 14.1%, p < 0.0001), depression (20.6% vs. 13.8%, p < 0.0001), ischemic heart disease (16.1% vs. 6.6%, p < 0.0001), obesity (7.9% vs. 2.5%, inpatient diagnoses only, p < 0.0001), and chronic kidney disease (5.2% vs. 1.3%, inpatient diagnoses only, p < 0.0001) compared with their non-PKU controls. Consequently, significantly more patients with late-diagnosed PKU received medication to treat comorbidities associated with the nervous (82.6% vs 77.0%; p = 0.0021) and cardiovascular system (69.5% vs 58.0%; p < 0.0001). Overall, only 3.4% of patients with late-diagnosed PKU received dietary amino-acid supplements and 0.7% received sapropterin. CONCLUSION The results indicate that PKU is associated with a significantly higher risk of comorbidities along with increased pharmaceutical prescriptions in patients with late-diagnosed PKU, compared with non-PKU controls. The increased risk of comorbidities was more pronounced than in patients with early-diagnosed PKU, as shown in previous research, but these patients are older than those with early-diagnosed PKU. Only few late-diagnosed patients were treated specifically for PKU. Patients with late-diagnosed PKU should be referred to specialized centers to prevent and manage comordities and introduce PKU-specific treatment when it is possible.
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Affiliation(s)
- Claire Douillard
- Service d'Endocrinologie, Diabétologie et Métabolisme et Centre de Référence des Maladies Héréditaires du Métabolisme, Hôpital Huriez, CHU de Lille, 59037 Lille, France.
| | - Jean-Baptiste Arnoux
- Centre de Référence des Maladies Héréditaires du Métabolisme, Hôpital Necker-Enfants Malades, APHP, 149 rue de Sèvres, 75015 Paris, France.
| | - Stéphane Bouée
- CEMKA, 43 boulevard du Maréchal Joffre, 92340 Bourg-La-Reine, France.
| | | | | | - Julia Theil
- Xcenda GmbH, Lange Laube 31, 30159 Hannover, Germany.
| | - Sybil Charrière
- Hospices Civils de Lyon, Department of endocrinology, diabetologia, metabolic diseases and nutrition, Hôpital Louis Pradel, 69600 Bron, France; CarMen laboratory, INSERM, INRAE, Université Claude Bernard Lyon 1, 69310, Pierre Bénite, France.
| | - Francois Maillot
- Service de médecine interne, CHRU et Université de Tours, Tours, France.
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Prepok FF, Schnabel KK, Sumánszki C, Barta AG, Tislér A, Reismann P. Long-Term Renal Function in Adult Patients with Phenylketonuria. Nephron Clin Pract 2023; 148:195-203. [PMID: 37757776 DOI: 10.1159/000531913] [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: 12/27/2022] [Accepted: 07/04/2023] [Indexed: 09/29/2023] Open
Abstract
INTRODUCTION In phenylketonuria (PKU), toxic phenylalanine (Phe) can harm other organs beyond the brain. Furthermore, the lifelong therapy of PKU consists of consumption of increased amounts of amino-acid mixture that provoke hyperfiltration in the glomeruli. Therefore, the adherence to therapy in PKU might influence the long-term kidney function in PKU patients. METHODS Data from 41 adult, early treated PKU patients were analyzed in this 10-year, retrospective, monocentric study. Two subgroups were created according to their therapy adherence: one with long-term blood Phe levels in the therapeutic range (<600 µmol/L), and one with suboptimal blood Phe levels. Renal function and metabolic parameters were collected over 10 years. Kidney function parameters were compared between the two groups and associations between blood Phe levels and kidney function were tested. RESULTS After 10 years, serum creatinine levels (p = 0.369) and estimated glomerular filtration rate (eGFR) (p = 0.723) did not change significantly from baseline in the good therapeutic group. The suboptimal therapeutic group's eGFR decreased in the same period (from 110.4 ± 14 mL/min/1.73 m2 to 94.2 ± 16 mL/min/1.73 m2, p = 0.017). At 10 years, the suboptimal therapeutic group had an increased serum creatinine level (81 ± 14.4 μmol/L vs. 71.5 ± 13 μmol/L, p = 0.038), and a decreased eGFR (94.2 ± 16 mL/min/1.73 m2 vs. 103.3 ± 13 mL/min/1.73 m2p = 0.031) compared to the good adhering group. Significant negative correlation between Phe levels and eGFR (r = -0.41, p = 0.008) was observed. CONCLUSION Long-term suboptimal therapy adherence in PKU patients with high blood Phe levels may lead to deterioration in kidney function.
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Affiliation(s)
| | | | - Csaba Sumánszki
- Department of Internal Medicine and Oncology, Semmelweis University, Budapest, Hungary
| | - András Gellért Barta
- Department of Internal Medicine and Oncology, Semmelweis University, Budapest, Hungary
| | - András Tislér
- Department of Internal Medicine and Oncology, Semmelweis University, Budapest, Hungary
| | - Péter Reismann
- Department of Internal Medicine and Oncology, Semmelweis University, Budapest, Hungary
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Rocha JC, Ahring KK, Bausell H, Bilder DA, Harding CO, Inwood A, Longo N, Muntau AC, Pessoa ALS, Rohr F, Sivri S, Hermida Á. Expert Consensus on the Long-Term Effectiveness of Medical Nutrition Therapy and Its Impact on the Outcomes of Adults with Phenylketonuria. Nutrients 2023; 15:3940. [PMID: 37764724 PMCID: PMC10536918 DOI: 10.3390/nu15183940] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 08/28/2023] [Accepted: 09/06/2023] [Indexed: 09/29/2023] Open
Abstract
Many adults with phenylketonuria (PKU) rely on medical nutrition therapy (MNT; low phenylalanine (Phe) diet with protein substitutes/medical foods) to maintain blood Phe concentrations within recommended ranges and prevent PKU-associated comorbidities. Despite disease detection through newborn screening and introduction of MNT as early as birth, adherence to MNT often deteriorates from childhood onwards, complicating the assessment of its effectiveness in the long term. Via a modified Delphi process, consensus (≥70% agreement) was sought on 19 statements among an international, multidisciplinary 13-member expert panel. After three iterative voting rounds, the panel achieved consensus on 17 statements related to the limitations of the long-term effectiveness of MNT (7), the burden of long-term reliance on MNT (4), and its potential long-term detrimental health effects (6). According to the expert panel, the effectiveness of MNT is limited in the long term, is associated with a high treatment burden, and demonstrates that adults with PKU are often unable to achieve metabolic control through dietary management alone, creating an unmet need in the adult PKU population.
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Affiliation(s)
- Júlio César Rocha
- NOVA Medical School, Faculdade de Ciências Médicas, Universidade NOVA de Lisboa, Campo Mártires da Pátria 130, 1169-056 Lisboa, Portugal
- Reference Centre of Inherited Metabolic Diseases, Centro Hospitalar Universitário de Lisboa Central, Rua Jacinta Marto, 1169-045 Lisboa, Portugal
- CINTESIS@RISE, Nutrition and Metabolism, NOVA Medical School, Faculdade de Ciências Médicas, NMS, FCM, Universidade NOVA de Lisboa, Campo Mártires da Pátria 130, 1169-056 Lisboa, Portugal
| | - Kirsten K. Ahring
- Departments of Paediatrics and Clinical Genetics, PKU Clinic, Copenhagen University Hospital, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen, Denmark
| | - Heather Bausell
- Division of Genetics, Genomics, and Metabolism, Ann & Robert H Lurie Children’s Hospital of Chicago, 225 E. Chicago Ave., Chicago, IL 60611, USA
| | - Deborah A. Bilder
- Department of Psychiatry, Division of Child & Adolescent Psychiatry, University of Utah Huntsman Mental Health Institute, 501 Chipeta Way, Salt Lake City, UT 84108, USA
| | - Cary O. Harding
- Department of Molecular and Medical Genetics, Oregon Health & Science University, 3222 SW Research Drive, Portland, OR 97239, USA
| | - Anita Inwood
- Queensland Lifespan Metabolic Medicine Service, Queensland Children’s Hospital, 501 Stanley St., South Brisbane, QLD 4101, Australia
- School of Nursing and Social Work, The University of Queensland, Chamberlain Building, St. Lucia, QLD 4072, Australia
| | - Nicola Longo
- Department of Pediatrics, Division of Medical Genetics, University of Utah School of Medicine, 295 Chipeta Way, Salt Lake City, UT 84108, USA
| | - Ania C. Muntau
- Department of Pediatrics, University Children’s Hospital, University Medical Centre Hamburg-Eppendorf, Martinistraße 52, 20246 Hamburg, Germany
| | - André L. Santos Pessoa
- Albert Sabin Children’s Hospital, R. Tertuliano Sales, 544—Vila União, Fortaleza 60410-794, CE, Brazil
- Av. Dr. Silas Munguba, 1700—Itaperi, State University of Ceará (UECE), Fortaleza 60714-903, CE, Brazil
| | | | - Serap Sivri
- Division of Pediatric Metabolism, Department of Pediatrics, Faculty of Medicine, Hacettepe University, Gevher Nesibe Cd., 06230 Ankara, Turkey
| | - Álvaro Hermida
- Diagnosis and Treatment of Congenital Metabolic Diseases Unit (UDyTEMC), Department of Pediatrics, Faculty of Medicine, Clinical University Hospital of Santiago de Compostela, University of Santiago de Compostela, CIBERER, MetabERN, Institute of Clinical Research of Santiago de Compostela (IDIS), Rúa de San Francisco s/n, 15706 Santiago de Compostela, Spain
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Rovelli V, Ercoli V, Dionigi AR, Paci S, Salvatici E, Zuvadelli J, Banderali G. Low bone mineralization in phenylketonuria may be due to undiagnosed metabolic acidosis. Mol Genet Metab Rep 2023; 36:100998. [PMID: 37600232 PMCID: PMC10432846 DOI: 10.1016/j.ymgmr.2023.100998] [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: 03/07/2023] [Revised: 08/04/2023] [Accepted: 08/04/2023] [Indexed: 08/22/2023] Open
Abstract
Background Dietary intervention is to date the mainstay treatment to prevent toxic phenylalanine (Phe) accumulation in PKU patients. Despite success preventing central nervous system damage, there is increasing evidence of possible other unfavorable outcomes affecting other systems, e.g. kidney and bone; underlying mechanisms are yet to be fully elucidated. Methods This observational, cross-sectional and descriptive study investigated 20 adult with PKU evaluating biochemical parameters, BMD measurements and extrapolating data from 3-days food records and protein substitutes (PS) and special low protein foods (SLPF) composition. Results Blood gas venous analysis (VBG) indices were indicative of metabolic acidosis in 60% of PKU patients and VBG pH significantly correlated with BMD's Z-score (p-value = 0.022) even if its overall mean was in range (-1.29). Low bone mineral density for chronological age (Z-score < - 2.0) was found in 4 patients (20%). Indices of kidney function were not impaired. All used PS had a moderate excess of acidity, while SLPF were alkalizing and type/variety of consumed vegetables did not determine significant changes in acid-base equilibrium. Total intakes of potassium and magnesium were lower than expected. Discussion PKU patients seem to be at risk of metabolic acidosis, directly linked to possible low bone mineralization. This may be related to the acidic composition of PS, potentially capable of acidifying the entire diet. Reported low intakes of potassium and magnesium may be relevant to these observations. Further studies are needed to better address these topics.
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Affiliation(s)
- Valentina Rovelli
- Clinical Department of Pediatrics, San Paolo Hospital, ASST Santi Paolo e Carlo, University of Milan, Italy
| | - Vittoria Ercoli
- Clinical Department of Pediatrics, San Paolo Hospital, ASST Santi Paolo e Carlo, University of Milan, Italy
| | - Alice Re Dionigi
- Clinical Department of Pediatrics, San Paolo Hospital, ASST Santi Paolo e Carlo, University of Milan, Italy
| | - Sabrina Paci
- Clinical Department of Pediatrics, San Paolo Hospital, ASST Santi Paolo e Carlo, University of Milan, Italy
| | - Elisabetta Salvatici
- Clinical Department of Pediatrics, San Paolo Hospital, ASST Santi Paolo e Carlo, University of Milan, Italy
| | - Juri Zuvadelli
- Clinical Department of Pediatrics, San Paolo Hospital, ASST Santi Paolo e Carlo, University of Milan, Italy
| | - Giuseppe Banderali
- Clinical Department of Pediatrics, San Paolo Hospital, ASST Santi Paolo e Carlo, University of Milan, Italy
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Charrière S, Maillot F, Bouée S, Douillard C, Jacob C, Schneider KM, Theil J, Arnoux JB. Health status and comorbidities of adult patients with phenylketonuria (PKU) in France with a focus on early-diagnosed patients - A nationwide study of health insurance claims data. Mol Genet Metab 2023; 139:107625. [PMID: 37329624 DOI: 10.1016/j.ymgme.2023.107625] [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: 01/05/2023] [Revised: 05/30/2023] [Accepted: 05/30/2023] [Indexed: 06/19/2023]
Abstract
BACKGROUND This study aimed at evaluating the health status and healthcare consumption of ≥16-year-old patients with phenylketonuria (PKU), with a focus on early-diagnosed patients. METHODS This retrospective observational study used health insurance claims data from the French SNDS (Système National des Données de Santé) database. Patients with PKU were identified between 2006 and 2018 by ICD-10 diagnosis codes E70.0 (classic PKU) or E70.1 (other causes of hyperphenylalaninemia). They were matched to controls by age, sex, and region. Patients with early-diagnosed PKU were defined as patients born after implementation of nationwide newborn screening in France in 1972. Outcomes were analyzed for the year 2018. RESULTS Overall, 3549 patients with PKU were identified on January 1st, 2018. Of those, 3469 patients could be matched to 17,170 controls without PKU. Of these patients, 2175 were at least 16 years old and suffered significantly more than controls from specific comorbidities of interest - osteoporosis (28.7% vs 19.8%, p < 0.0001), hypertension (20.9% vs 17.0%, p < 0.0001), hypercholesterolemia (12.8% vs 8.3%, p < 0.0001), diabetes (7.8% vs 4.7%, p < 0.0001), obesity (4.2% vs 1.3%, p < 0.0001), ischemic heart diseases (4.8% vs 2.0%, p < 0.0001), and depression (10.3% vs 8.2%, p = 0.0011). Prescriptions for many medications were also more frequent in patients with PKU than controls. Among ≥16-year-old patients, 1528 were categorized as early-diagnosed. Osteoporosis (0.3% vs 0.01%, p = 0.0035), chronic renal failure (0.6% vs 0.1%, p = 0.0020), hypertension (4.0% vs 2.7%, p = 0.0063), and obesity (2.5% vs 0.8%, p < 0.0001) were significantly more prevalent in early-diagnosed adult patients compared with matched controls. In total, 28.6% of ≥16-year-old patients with PKU and 40.4% of early-diagnosed patients with PKU received dietary amino-acid supplements. Sapropterin was prescribed to 5.0% and 7.0% patients, respectively. CONCLUSION The results indicate that PKU is associated with a significantly higher comorbidity risk along with increased pharmaceutical prescriptions in adulthood. The comorbidity burden is less distinct in early-diagnosed patients but still present. Few patients are treated specifically for PKU in adulthood. Healthcare of patients with PKU should include prevention and management of comorbidities and especially target PKU-specific treatment adherence and consistent care in specialized medical centers in adulthood.
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Affiliation(s)
- Sybil Charrière
- Hospices Civils de Lyon, Department of endocrinology, diabetologia, metabolic diseases and nutrition, Hôpital Louis Pradel, 69600 BRON, France. CarMen laboratory, INSERM, INRAE, Université Claude Bernard Lyon 1, 69310, Pierre Bénite, France.
| | - Francois Maillot
- Service de médecine interne, CHRU et Université de Tours, UMR INSERM 1253 « iBrain », Tours, France.
| | - Stéphane Bouée
- CEMKA, 43 boulevard du Maréchal Joffre, 92340, Bourg-La-Reine, France.
| | - Claire Douillard
- Service d'endocrinologie, diabétologie, métabolisme et nutrition, Centre de Référence des Maladies Héréditaires du Métabolisme, Hôpital Huriez, CHU de Lille, 59037 Lille, France.
| | | | | | - Julia Theil
- Xcenda GmbH, Lange Laube 31, 30159 Hannover, Germany.
| | - Jean-Baptiste Arnoux
- Centre de Référence des Maladies Héréditaires du Métabolisme, Hôpital Necker-Enfants Malades, APHP, 149 rue de Sèvres, 75015 Paris, France.
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Cannet C, Bayat A, Frauendienst-Egger G, Freisinger P, Spraul M, Himmelreich N, Kockaya M, Ahring K, Godejohann M, MacDonald A, Trefz F. Phenylketonuria (PKU) Urinary Metabolomic Phenotype Is Defined by Genotype and Metabolite Imbalance: Results in 51 Early Treated Patients Using Ex Vivo 1H-NMR Analysis. Molecules 2023; 28:4916. [PMID: 37446577 DOI: 10.3390/molecules28134916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 06/13/2023] [Accepted: 06/14/2023] [Indexed: 07/15/2023] Open
Abstract
Phenylketonuria (PKU) is a rare metabolic disorder caused by mutations in the phenylalanine hydroxylase gene. Depending on the severity of the genetic mutation, medical treatment, and patient dietary management, elevated phenylalanine (Phe) may occur in blood and brain tissues. Research has recently shown that high Phe not only impacts the central nervous system, but also other organ systems (e.g., heart and microbiome). This study used ex vivo proton nuclear magnetic resonance (1H-NMR) analysis of urine samples from PKU patients (mean 14.9 ± 9.2 years, n = 51) to identify the impact of elevated blood Phe and PKU treatment on metabolic profiles. Our results found that 24 out of 98 urinary metabolites showed a significant difference (p < 0.05) for PKU patients compared to age-matched healthy controls (n = 51) based on an analysis of urinary metabolome. These altered urinary metabolites were related to Phe metabolism, dysbiosis, creatine synthesis or intake, the tricarboxylic acid (TCA) cycle, end products of nicotinamide-adenine dinucleotide degradation, and metabolites associated with a low Phe diet. There was an excellent correlation between the metabolome and genotype of PKU patients and healthy controls of 96.7% in a confusion matrix model. Metabolomic investigations may contribute to a better understanding of PKU pathophysiology.
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Affiliation(s)
| | - Allan Bayat
- Kennedy Centre, Center for PKU, 2600 Glostrup, Denmark
| | | | - Peter Freisinger
- Department of Pediatrics, School of Medicine, University of Tübingen, 72074 Tübingen, Germany
| | | | | | - Musa Kockaya
- Private Pediatric Practice, 68307 Mannheim, Germany
| | | | | | - Anita MacDonald
- Dietetic Department, Birmingham Children's Hospital, Birmingham B4 6NH, UK
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Moritz L, Klotz K, Grünert SC, Hannibal L, Spiekerkoetter U. Metabolic phenotyping in phenylketonuria reveals disease clustering independently of metabolic control. Mol Genet Metab 2023; 138:107509. [PMID: 36791482 DOI: 10.1016/j.ymgme.2023.107509] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 01/11/2023] [Accepted: 01/12/2023] [Indexed: 01/17/2023]
Abstract
Phenylketonuria (PKU, MIM #261600) is one of the most common inborn errors of metabolism (IEM) with an incidence of 1:10000 in the European population. PKU is caused by autosomal recessive mutations in phenylalanine hydroxylase (PAH) and manifests with elevation of phenylalanine (Phe) in plasma and urine. Untreated PKU manifests with intellectual disability including seizures, microcephaly and behavioral abnormalities. Early treatment and good compliance result in a normal intellectual outcome in many but not in all patients. This study examined plasma metabolites in patients with PKU (n = 27), hyperphenylalaninemia (HPA, n = 1) and healthy controls (n = 32) by LC- MS/MS. We hypothesized that PKU patients would exhibit a distinct "submetabolome" compared to that of healthy controls. We further hypothesized that the submetabolome of PKU patients with good metabolic control would resemble that of healthy controls. Results from this study show: (i) Distinct clustering of healthy controls and PKU patients based on polar metabolite profiling, (ii) Increased and decreased concentrations of metabolites within and afar from the Phe pathway in treated patients, and (iii) A specific PKU-submetabolome independently of metabolic control assessed by Phe in plasma. We examined the relationship between PKU metabolic control and extended metabolite profiles in plasma. The PKU submetabolome characterized in this study represents the combined effects of dietary adherence, adjustments in metabolic pathways to compensate for defective Phe processing, as well as metabolic derangements that could not be corrected with dietary management even in patients classified as having good metabolic control. New therapeutic targets may be uncovered to approximate the PKU submetabolome to that of healthy controls and prevent long-term organ damage.
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Affiliation(s)
- Lennart Moritz
- Laboratory of Clinical Biochemistry and Metabolism, Department of General Pediatrics, Adolescent Medicine and Neonatology, Faculty of Medicine, Medical Center, University of Freiburg, 79106 Freiburg, Germany; Department of General Pediatrics, Adolescent Medicine and Neonatology, Faculty of Medicine, Medical Center, University of Freiburg, 79106 Freiburg, Germany
| | - Katharina Klotz
- Laboratory of Clinical Biochemistry and Metabolism, Department of General Pediatrics, Adolescent Medicine and Neonatology, Faculty of Medicine, Medical Center, University of Freiburg, 79106 Freiburg, Germany
| | - Sarah Catharina Grünert
- Department of General Pediatrics, Adolescent Medicine and Neonatology, Faculty of Medicine, Medical Center, University of Freiburg, 79106 Freiburg, Germany
| | - Luciana Hannibal
- Laboratory of Clinical Biochemistry and Metabolism, Department of General Pediatrics, Adolescent Medicine and Neonatology, Faculty of Medicine, Medical Center, University of Freiburg, 79106 Freiburg, Germany.
| | - Ute Spiekerkoetter
- Department of General Pediatrics, Adolescent Medicine and Neonatology, Faculty of Medicine, Medical Center, University of Freiburg, 79106 Freiburg, Germany.
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9
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Arslan E, Gokcay GF. Special low protein foods for phenylketonuria in Turkey: An examination of their nutritional composition compared to regular food. Nutr Health 2023:2601060221146580. [PMID: 36591892 DOI: 10.1177/02601060221146580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Background: Special low protein foods (SLPF) that are phenylalanine (Phe)-free or have a low Phe content are an integral part of PKU diet therapy. Aim: The aim of this study is to determine the nutritional profiles of SLPFs used in Turkey and to compare their contents with equivalent products in the "regular" category, in order to evaluate nutritional and metabolic risks. Methods: Between February and March 2022, the information concerning the nutritional contents of "special low protein products" recommended for PKU and available in Turkey were obtained from the websites of producers/suppliers. Results: A total of 148 SLPFs were identified in Turkey. Compared to regular products, SLPFs were determined to contain less sugar and high carbohydrate content in the Turkish market (p < 0.001). Overall, SLPF products had higher dietary fiber compared to products with regular protein content (p < 0.001). In SLPF subgroups, meat substitutes, rice and pasta, and soup products had significantly less total fat than regular products; low protein bread, sweet snacks, and salted crackers were found to contain less saturated fat (p < 0.05). Moreover, all SLPFs contained significantly more salt than regular products, especially the salt content of subgroups of low protein bread, flour, pasta, and rice was significantly higher than regular products (p < 0.05). Conclusion: Including detailed nutritional information on the Turkish SLPFs' food labels will be effective for patients with PKU to follow themselves on their own.
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Affiliation(s)
- Ezgi Arslan
- Department of Nutrition and Dietetics, Faculty of Health Sciences, 52946Bahcesehir University, Istanbul, Turkey
| | - Gulden Fatma Gokcay
- Department of Pediatrics, 37516Istanbul University, Istanbul Faculty of Medicine, Istanbul, Turkey
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10
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McWhorter N, Ndugga-Kabuye MK, Puurunen M, Ernst SL. Complications of the Low Phenylalanine Diet for Patients with Phenylketonuria and the Benefits of Increased Natural Protein. Nutrients 2022; 14:4960. [PMID: 36500989 PMCID: PMC9740314 DOI: 10.3390/nu14234960] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 11/18/2022] [Accepted: 11/21/2022] [Indexed: 11/24/2022] Open
Abstract
Phenylketonuria (PKU) is an inherited disorder in which phenylalanine (Phe) is not correctly metabolized leading to an abnormally high plasma Phe concentration that causes profound neurologic damage if left untreated. The mainstay of treatment for PKU has centered around limiting natural protein in the diet while supplementing with medical foods in order to prevent neurologic injury while promoting growth. This review discusses several deleterious effects of the low Phe diet along with benefits that have been reported for patients with increased natural protein intake while maintaining plasma Phe levels within treatment guidelines.
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11
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Cacicedo ML, Weinl-Tenbruck C, Frank D, Limeres MJ, Wirsching S, Hilbert K, Pasha Famian MA, Horscroft N, Hennermann JB, Zepp F, Chevessier-Tünnesen F, Gehring S. Phenylalanine hydroxylase mRNA rescues the phenylketonuria phenotype in mice. Front Bioeng Biotechnol 2022; 10:993298. [PMID: 36277393 PMCID: PMC9585315 DOI: 10.3389/fbioe.2022.993298] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Accepted: 09/16/2022] [Indexed: 11/13/2022] Open
Abstract
Phenylketonuria (PKU) is an inborn error of metabolism caused by a deficiency in functional phenylalanine hydroxylase (PAH), resulting in accumulation of phenylalanine (Phe) in patients’ blood and organs. Affected patients encounter severe developmental delay, neurological deficits, and behavioral abnormalities when not treated. Early diagnosis and treatment are extremely important; newborn screening programs have been implemented in most countries to ensure early identification of patients with PKU. Despite available treatment options, several challenges remain: life-long adherence to a strict diet, approval of some medications for adults only, and lack of response to these therapies in a subpopulation of patients. Therefore, there is an urgent need for treatment alternatives. An mRNA-based approach tested in PKU mice showed a fast reduction in the accumulation of Phe in serum, liver and brain, the most significant organ affected. Repeated injections of LNP-formulated mouse PAH mRNA rescued PKU mice from the disease phenotype for a prolonged period of time. An mRNA-based approach could improve the quality of life tremendously in PKU patients of all ages by replacing standard-of-care treatments.
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Affiliation(s)
- Maximiliano L. Cacicedo
- Children’s Hospital, University Medical Center of the Johannes-Gutenberg University, Mainz, Germany
- *Correspondence: Maximiliano L. Cacicedo,
| | | | - Daniel Frank
- Children’s Hospital, University Medical Center of the Johannes-Gutenberg University, Mainz, Germany
| | - Maria Jose Limeres
- Children’s Hospital, University Medical Center of the Johannes-Gutenberg University, Mainz, Germany
| | - Sebastian Wirsching
- Children’s Hospital, University Medical Center of the Johannes-Gutenberg University, Mainz, Germany
| | - Katja Hilbert
- Children’s Hospital, University Medical Center of the Johannes-Gutenberg University, Mainz, Germany
| | | | | | - Julia B. Hennermann
- Children’s Hospital, University Medical Center of the Johannes-Gutenberg University, Mainz, Germany
| | - Fred Zepp
- Children’s Hospital, University Medical Center of the Johannes-Gutenberg University, Mainz, Germany
| | | | - Stephan Gehring
- Children’s Hospital, University Medical Center of the Johannes-Gutenberg University, Mainz, Germany
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12
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Burton BK, Hermida Á, Bélanger-Quintana A, Bell H, Bjoraker KJ, Christ SE, Grant ML, Harding CO, Huijbregts SCJ, Longo N, McNutt MC, Nguyen-Driver MD, Santos Pessoa AL, Rocha JC, Sacharow S, Sanchez-Valle A, Sivri HS, Vockley J, Walterfang M, Whittle S, Muntau AC. Management of early treated adolescents and young adults with phenylketonuria: Development of international consensus recommendations using a modified Delphi approach. Mol Genet Metab 2022; 137:114-126. [PMID: 36027720 DOI: 10.1016/j.ymgme.2022.07.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Revised: 06/16/2022] [Accepted: 07/23/2022] [Indexed: 11/20/2022]
Abstract
BACKGROUND Early treated patients with phenylketonuria (PKU) often become lost to follow-up from adolescence onwards due to the historical focus of PKU care on the pediatric population and lack of programs facilitating the transition to adulthood. As a result, evidence on the management of adolescents and young adults with PKU is limited. METHODS Two meetings were held with a multidisciplinary international panel of 25 experts in PKU and comorbidities frequently experienced by patients with PKU. Based on the outcomes of the first meeting, a set of statements were developed. During the second meeting, these statements were voted on for consensus generation (≥70% agreement), using a modified Delphi approach. RESULTS A total of 37 consensus recommendations were developed across five areas that were deemed important in the management of adolescents and young adults with PKU: (1) general physical health, (2) mental health and neurocognitive functioning, (3) blood Phe target range, (4) PKU-specific challenges, and (5) transition to adult care. The consensus recommendations reflect the personal opinions and experiences from the participating experts supported with evidence when available. Overall, clinicians managing adolescents and young adults with PKU should be aware of the wide variety of PKU-associated comorbidities, initiating screening at an early age. In addition, management of adolescents/young adults should be a joint effort between the patient, clinical center, and parents/caregivers supporting adolescents with gradually gaining independent control of their disease during the transition to adulthood. CONCLUSIONS A multidisciplinary international group of experts used a modified Delphi approach to develop a set of consensus recommendations with the aim of providing guidance and offering tools to clinics to aid with supporting adolescents and young adults with PKU.
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Affiliation(s)
- Barbara K Burton
- Ann and Robert H. Lurie Children's Hospital and Northwestern University Feinberg School of Medicine, Chicago, IL, USA.
| | - Álvaro Hermida
- Clinical University Hospital of Santiago de Compostela, University of Santiago de Compostela, CIBERER, MetabERN, Institute of Clinical Research of Santiago de Compostela (IDIS), Santiago de Compostela, Spain
| | | | - Heather Bell
- Fred A. Litwin Family Centre in Genetic Medicine, University Health Network and Mount Sinai Hospital, Toronto, ON, Canada
| | | | - Shawn E Christ
- Department of Psychological Sciences, University of Missouri, Columbia, MO, USA
| | - Mitzie L Grant
- Department of Psychiatry, Drexel University College of Medicine, Philadelphia, PA, USA
| | - Cary O Harding
- Department of Molecular and Medical Genetics, Oregon Health & Science University, Portland, OR, USA
| | | | - Nicola Longo
- Division of Medical Genetics, Department of Pediatrics, University of Utah, Salt Lake City, UT, USA
| | - Markey C McNutt
- McDermott Center for Human Growth and Development, UT Southwestern Medical Center, Dallas, TX, USA
| | - Mina D Nguyen-Driver
- Department of Molecular and Medical Genetics, Oregon Health & Science University, Portland, OR, USA
| | - André L Santos Pessoa
- Pediatric Neurology Service, Albert Sabin Children's Hospital, University of Ceará State, Fortaleza, Ceará, Brazil
| | - Júlio César Rocha
- Nutrition and Metabolism, NOVA Medical School, Faculdade de Ciências Médicas, Universidade NOVA de Lisboa, Portugal; Neuropsychiatry Unit, Royal Melbourne Hospital, Melbourne, VIC, Australia; Melbourne Neuropsychiatry Centre, University of Melbourne, Melbourne, VIC, Australia
| | - Stephanie Sacharow
- CINTESIS-Center for Health Technology and Services Research, NOVA Medical School, Lisboa, Portugal; Florey Institute of Neuroscience and Mental Health, Melbourne, VIC, Australia
| | - Amarilis Sanchez-Valle
- Reference Centre of Inherited Metabolic Diseases, Centro Hospitalar Universitário de Lisboa Central, Lisboa, Portugal
| | - H Serap Sivri
- Division of Genetics and Genomics, Boston Children's Hospital, Boston, MA, USA
| | - Jerry Vockley
- Department of Pediatrics, Harvard Medical School, Boston, MA, USA
| | - Mark Walterfang
- Department of Pediatrics, Morsani College of Medicine, University of South Florida, Tampa, FL, USA; Melbourne Neuropsychiatry Centre, Department of Psychiatry, University of Melbourne, Melbourne, VIC, Australia; University Children's Hospital, University Medical Center Hamburg Eppendorf, Hamburg, Germany
| | - Sarah Whittle
- Hacettepe University, Faculty of Medicine, Department of Pediatrics, Section of Pediatric Metabolism, Ankara, Turkey
| | - Ania C Muntau
- Department of Pediatrics, University of Pittsburgh Medical Center Children's Hospital of Pittsburgh, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
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13
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McWhorter N, Dhillon J, Hoffman J. Preliminary Investigation of Microbiome and Dietary Differences in Patients with Phenylketonuria on Enzyme Substitution Therapy Compared to Traditional Therapies. J Acad Nutr Diet 2021; 122:1283-1295.e3. [PMID: 34968752 DOI: 10.1016/j.jand.2021.12.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 12/20/2021] [Accepted: 12/21/2021] [Indexed: 11/30/2022]
Abstract
BACKGROUND Phenylketonuria (PKU) is an inborn error of metabolism that impairs the function of the enzyme phenylalanine hydroxylase (PAH). Historical treatment includes limiting dietary phenylalanine (Phe) consumption while supplementing with medical food; however, this treatment has been associated with complications, such as nutritional deficiencies and disruptions in the gut microbiota. OBJECTIVE The study aim was to compare dietary and gut microbiome differences between adult patients on a traditional PKU diet to those receiving the enzyme substitution therapy Palynziq on a liberalized diet while controlling blood Phe levels to <600 μmol/L. DESIGN A cross-sectional study was conducted comparing patients on a traditional Phe-restricted diet with patients receiving Palynziq eating a liberalized diet. PARTICIPANTS/SETTING Six patients eating a traditional Phe-restricted diet with medical food and six patients on Palynziq eating a liberalized diet without medical food intake for >3 years were selected from the University of Kentucky Metabolic Clinic August to December 2019. MAIN OUTCOME MEASURES Nutrient intake from three-day diet records and fecal microbiome taxonomic abundances were analyzed. STATISTICAL ANALYSIS Mann-Whitney U-tests were used for dietary data analysis. Differential abundance analysis for microbiome taxa and pathway data was done using DESeq2 analysis. RESULTS Dietary data showed Palynziq patients consumed a lower percent of kilocalories from total protein and lower amounts of most micronutrients but consumed greater amounts of intact protein and cholesterol (P<0.05). Microbiome data revealed a greater abundance of the phylum Verrucomicrobia and genus Lachnobacterium in the Traditional group and a greater abundance of the genus Prevotella in the Palynziq group (P<0.05). Pathway analysis depicted greater enrichment in carotenoid and amino acid metabolism pathways in the Traditional group (P<0.05). Protein (%kcal), dietary fiber (g), fat (%kcal), linolenic acid (%DRI), and age were correlated with the underlying microbial community structure for both groups combined. CONCLUSIONS Patients with PKU treated with Palynziq on a liberalized diet manifest significant differences in diet composition compared to those treated with traditional Phe-restricted diets. Several of these dietary differences may affect the microbiome architecture.
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Affiliation(s)
- Nicole McWhorter
- Metabolic Dietitian, Department of Pediatrics, Division of Genetics and Metabolism, University of Kentucky, 138 Leader Ave., Lexington, KY 40508, USA, Synlogic Therapeutics, 301 Binney St #402, Cambridge, MA 02142.
| | - Jaapna Dhillon
- Assistant Professor, Department of Nutrition and Exercise Physiology, School of Medicine, University of Missouri-Columbia, Gwynn Hall, Room 312, 520 Hitt Street
| | - Jessie Hoffman
- Assistant Professor, Department of Human Nutrition, College of Arts & Sciences, Winthrop University, Dalton Hall 306A, Rock Hill, SC 29733
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14
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Maceda EBG, Abadingo ME, Magbanua-Calalo CJ, Dator MA, Resontoc LPR, Castro-Hamoy LD, Abacan MAR, Chiong MAD, Estrada SC. Maple syrup urine disease associated with nephrotic syndrome in a Filipino child. BMJ Case Rep 2021; 14:14/7/e242689. [PMID: 34326111 PMCID: PMC8323351 DOI: 10.1136/bcr-2021-242689] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
A 22-month-old female child with maple syrup urine disease (MSUD) presented with generalised oedema. Diagnostic evaluation revealed nephrotic range proteinuria, hypoalbuminaemia and dyslipidaemia supporting the diagnosis of nephrotic syndrome (NS). Diet, being at the core of the management plan for both MSUD and NS, necessitated regular monitoring and evaluation via dried blood spot collection of leucine. The opposing requirement for total protein for both disorders (that is protein restriction in MSUD and protein supplementation in NS) prompted a careful balancing act of the dietary management. The monitoring, which revealed normal leucine levels on multiple determinations, allowed an eventual increase in dietary protein and daily administration of albumin to address the NS. Dietary protein increase, both in total protein (3.5 g/kg/day) and natural protein (1 g/kg/day) levels, was instituted. It was observed that NS does not trigger leucinosis and allowed easing of protein restriction in MSUD.
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Affiliation(s)
- Ebner Bon G Maceda
- Division of Clinical Genetics, Department of Pediatrics, Philippine General Hospital, University of the Philippines Manila, Manila, Philippines .,Institute of Human Genetics, National Institutes of Health, University of the Philippines Manila, Manila, Philippines
| | - Michelle E Abadingo
- Division of Clinical Genetics, Department of Pediatrics, Philippine General Hospital, University of the Philippines Manila, Manila, Philippines.,Newborn Screening Reference Center, National Institutes of Health, University of the Philippines Manila, Manila, Philippines
| | - Cheryll J Magbanua-Calalo
- Division of Clinical Genetics, Department of Pediatrics, Philippine General Hospital, University of the Philippines Manila, Manila, Philippines.,Newborn Screening Reference Center, National Institutes of Health, University of the Philippines Manila, Manila, Philippines
| | - Melissa A Dator
- Division of Pediatric Nephrology, Department of Pediatrics, Philippine General Hospital, University of the Philippines Manila, Manila, Philippines
| | - Lourdes Paula R Resontoc
- Division of Pediatric Nephrology, Department of Pediatrics, Philippine General Hospital, University of the Philippines Manila, Manila, Philippines
| | - Leniza De Castro-Hamoy
- Division of Clinical Genetics, Department of Pediatrics, Philippine General Hospital, University of the Philippines Manila, Manila, Philippines.,Institute of Human Genetics, National Institutes of Health, University of the Philippines Manila, Manila, Philippines
| | - Mary Ann R Abacan
- Division of Clinical Genetics, Department of Pediatrics, Philippine General Hospital, University of the Philippines Manila, Manila, Philippines.,Institute of Human Genetics, National Institutes of Health, University of the Philippines Manila, Manila, Philippines
| | - Mary Anne D Chiong
- Division of Clinical Genetics, Department of Pediatrics, Philippine General Hospital, University of the Philippines Manila, Manila, Philippines.,Institute of Human Genetics, National Institutes of Health, University of the Philippines Manila, Manila, Philippines.,Department of Biochemistry, Molecular Biology and Nutrition, University of Santo Tomas Faculty of Medicine and Surgery, Manila, Philippines
| | - Sylvia C Estrada
- Division of Clinical Genetics, Department of Pediatrics, Philippine General Hospital, University of the Philippines Manila, Manila, Philippines.,Institute of Human Genetics, National Institutes of Health, University of the Philippines Manila, Manila, Philippines
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15
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Fernandes Silva L, Vangipurapu J, Smith U, Laakso M. Metabolite Signature of Albuminuria Involves Amino Acid Pathways in 8661 Finnish Men Without Diabetes. J Clin Endocrinol Metab 2021; 106:143-152. [PMID: 32992327 PMCID: PMC7765644 DOI: 10.1210/clinem/dgaa661] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Accepted: 09/28/2020] [Indexed: 12/29/2022]
Abstract
OBJECTIVE To investigate the metabolite signature of albuminuria in individuals without diabetes or chronic kidney disease to identify possible mechanisms that result in increased albuminuria and elevated risk of type 2 diabetes (T2D). RESEARCH DESIGN AND METHODS The study cohort was a population-based Metabolic Syndrome In Men (METSIM) study including 8861 middle-aged and elderly Finnish men without diabetes or chronic kidney disease at baseline. A total of 5504 men participated in a 7.5-year follow-up study, and 5181 of them had metabolomics data measured by Metabolon's ultrahigh performance liquid chromatography-tandem mass spectroscopy. RESULTS We found 32 metabolites significantly (P < 5.8 × 10-5) and positively associated with the urinary albumin excretion (UAE) rate. These metabolites were especially downstream metabolites in the amino acid metabolism pathways (threonine, phenylalanine, leucine, arginine). In our 7.5-year follow-up study, UAE was significantly associated with a 19% increase (hazard ratio 1.19; 95% confidence interval, 1.13-1.25) in the risk of T2D after the adjustment for confounding factors. Conversion to diabetes was more strongly associated with a decrease in insulin secretion than a decrease in insulin sensitivity. CONCLUSIONS Metabolic signature of UAE included multiple metabolites, especially from the amino acid metabolism pathways known to be associated with low-grade inflammation, and accumulation of reactive oxygen species that play an important role in the pathogenesis of UAE. These metabolites were primarily associated with an increase in UAE and were secondarily associated with a decrease in insulin secretion and insulin sensitivity, resulting in an increased risk of incident T2D.
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Affiliation(s)
- Lilian Fernandes Silva
- Institute of Clinical Medicine, Internal Medicine, University of Eastern Finland, Kuopio, Finland
| | - Jagadish Vangipurapu
- Institute of Clinical Medicine, Internal Medicine, University of Eastern Finland, Kuopio, Finland
| | - Ulf Smith
- Lundberg Laboratory for Diabetes Research, Department of Molecular and Clinical Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Markku Laakso
- Institute of Clinical Medicine, Internal Medicine, University of Eastern Finland, Kuopio, Finland
- Kuopio University Hospital, Kuopio, Finland
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16
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Firman S, Witard OC, O'Keeffe M, Ramachandran R. Dietary protein and protein substitute requirements in adults with phenylketonuria: A review of the clinical guidelines. Clin Nutr 2020; 40:702-709. [PMID: 33308842 DOI: 10.1016/j.clnu.2020.11.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 10/17/2020] [Accepted: 11/01/2020] [Indexed: 10/23/2022]
Abstract
Lifelong dietary treatment is recommended in the management of phenylketonuria (PKU). Accordingly, an increasing adult population require age-specific PKU guidelines on protein requirements to support changing metabolic demands across the lifespan. Given that protein intake for dietary management of PKU is primarily (52-80%) derived from protein substitutes, the prescribing practice of protein substitutes must be underpinned by robust evidence. Whilst dietary guidelines for PKU management is evolving to incorporate adult specific protein recommendations, the scientific evidence underpinning these guidelines is currently limited. Instead, the determination of protein requirements for people with PKU have previously been extrapolated from estimates derived from the general healthy population, based on arguably outdated nitrogen balance methodology. Furthermore, a compensatory factor of 20-40% has been incorporated to account for the reduced uptake and utilisation of the elemental amino acids contained in protein substitutes. However, research informing this compensatory factor has been conducted in younger adults, with the majority of studies in non-PKU individuals. Given extensive evidence that the muscle anabolic response to ingested protein is impaired in older vs. young adults, the validity of current dietary protein recommendations for adults and older adults with PKU has been challenged. This narrative review aims to critically evaluate the existing scientific evidence underpinning current guidelines on protein requirements for adults with PKU, highlighting existing gaps in knowledge and directions for future research. We argue that current guidelines on protein requirements need updating to optimise long-term physical and functional outcomes in older adults with PKU.
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Affiliation(s)
- Sarah Firman
- Department of Nutritional Sciences, King's College London, London, United Kingdom; Department of Nutrition and Dietetics, Guy's and St Thomas' NHS Foundation Trust, London, United Kingdom; Adult Inherited Metabolic Diseases, Guy's and St Thomas' NHS Foundation Trust, London, United Kingdom.
| | - Oliver C Witard
- Department of Nutritional Sciences, King's College London, London, United Kingdom; Centre for Human and Applied Physiological Sciences, King's College London, London, United Kingdom
| | - Majella O'Keeffe
- Department of Nutritional Sciences, King's College London, London, United Kingdom; School of Food and Nutritional Sciences, University College Cork, College Road, Cork, Ireland
| | - Radha Ramachandran
- Adult Inherited Metabolic Diseases, Guy's and St Thomas' NHS Foundation Trust, London, United Kingdom
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17
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Stroup BM, Murali SG, Schwahn DJ, Sawin EA, Lankey EM, Bächinger HP, Ney DM. Sex effects of dietary protein source and acid load on renal and bone status in the Pah enu2 mouse model of phenylketonuria. Physiol Rep 2020; 7:e14251. [PMID: 31650703 PMCID: PMC6813258 DOI: 10.14814/phy2.14251] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Accepted: 09/07/2019] [Indexed: 01/17/2023] Open
Abstract
The low‐phenylalanine (Phe) diet with amino acid (AA) medical foods is associated with low bone mineral density (BMD) and renal dysfunction in human phenylketonuria (PKU). Our objective was to determine if diets differing in dietary protein source and acid load alter bone and renal outcomes in Pah−/− and wild‐type (WT) mice. Female and male Pah−/− (Pahenu2/enu2) and WT littermates (C57BL/6 background) were fed high‐acid AA, buffered AA (BAA), glycomacropeptide (GMP), or high‐Phe casein diets from 3 to 24 weeks of age. The BAA diet significantly reduced the excretion of renal net acid and ammonium compared with the AA diet. Interestingly, the BAA diet did not improve renal dilation in hematoxylin and eosin (H&E) stained renal sections, femoral biomechanical parameters, or femoral bone mineral content (BMC). Significantly lower femoral BMC and strength occurred in Pah−/− versus WT mice, with greater decline in female Pah−/− mice. Polyuria and mild vacuolation in the proximal convoluted tubules were observed in male Pah−/− and WT mice fed the high‐acid AA diet versus absent/minimal cortical vacuolation in males fed the GMP, BAA, or casein diets. Vacuole contents in male mice were proteinaceous. Cortical vacuolation was absent in female mice. Dilated medullary tubules were observed in all Pah−/− mice, except for male Pah−/− mice fed the GMP diet. In summary, the PKU genotype and diet showed differential effects on renal and bone status in male and female mice. Renal status improved in male Pah−/− mice fed the GMP diet.
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Affiliation(s)
- Bridget M Stroup
- Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, Wisconsin.,Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas
| | - Sangita G Murali
- Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, Wisconsin
| | | | - Emily A Sawin
- Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, Wisconsin
| | - Emma M Lankey
- Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, Wisconsin
| | - Hans Peter Bächinger
- Department of Biochemistry and Molecular Biology, Oregon Health Sciences University, Portland, Oregon
| | - Denise M Ney
- Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, Wisconsin
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18
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Manta-Vogli PD, Dotsikas Y, Loukas YL, Schulpis KH. The phenylketonuria patient: A recent dietetic therapeutic approach. Nutr Neurosci 2020; 23:628-639. [PMID: 30359206 DOI: 10.1080/1028415x.2018.1538196] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Phenylalanine hydroxylase (PAH) deficiency, commonly named phenylketonuria (PKU) is a disorder of phenylalanine (Phe) metabolism inherited with an autosomal recessive trait. It is characterized by high blood and cerebral Phe levels, resulting in intellectual disabilities, seizures, etc. Early diagnosis and treatment of the patients prevent major neuro-cognitive deficits. Treatment consists of a lifelong restriction of Phe intake, combined with the supplementation of special medical foods, such as Amino Acid medical food (AA-mf), enriched in tyrosine (Tyr) and other amino acids and nutrients to avoid nutritional deficits. Developmental and neurocognitive outcomes for patients, however, remain suboptimal, especially when adherence to the demanding diet is poor. Additions to treatment include new, more palatable foods, based on Glycomacropeptide that contains limited amounts of Phe, the administration of large neutral amino acids to prevent phenylalanine entry into the brain and tetrahydrobiopterin cofactor capable of increasing residual PAH activity. Moreover, further efforts are underway to develop an oral therapy containing phenylalanine ammonia-lyase. Nutritional support of PKU future mothers (maternal PKU) is also discussed. This review aims to summarize the current literature on new PKU treatment strategies.
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Affiliation(s)
- Penelope D Manta-Vogli
- Department of Clinical Nutrition & Dietetics Agia Sofia Children's Hospital, Athens, Greece
| | - Yannis Dotsikas
- Department of Pharmacy, Laboratory of Pharm. Analysis, National and Kapodestrian University of Athens, Panepistimiopolis Zographou, GR 157 71, Athens, Greece
| | - Yannis L Loukas
- Department of Pharmacy, Laboratory of Pharm. Analysis, National and Kapodestrian University of Athens, Panepistimiopolis Zographou, GR 157 71, Athens, Greece
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19
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Scheinin M, Barassi A, Junnila J, Lovró Z, Reiner G, Sarkkinen E, MacDonald A. Amino Acid Plasma Profiles from a Prolonged-Release Protein Substitute for Phenylketonuria: A Randomized, Single-Dose, Four-Way Crossover Trial in Healthy Volunteers. Nutrients 2020; 12:nu12061653. [PMID: 32498426 PMCID: PMC7352445 DOI: 10.3390/nu12061653] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 05/21/2020] [Accepted: 05/26/2020] [Indexed: 12/12/2022] Open
Abstract
Several disorders of amino acid (AA) metabolism are treated with a protein-restricted diet supplemented with specific AA mixtures. Delivery kinetics impacts AA absorption and plasma concentration profiles. We assessed plasma profiles after ingestion of an AA mixture engineered to prolong AA absorption with Physiomimic TechnologyTM (Test) in a randomized, single-dose, four-way crossover trial in healthy volunteers (Trial Registration: ISRCTN11016729). In a two-step hypothesis, the primary endpoints were (i) significant reduction in peak plasma concentrations (Cmax) of essential amino acids (EAAs) while (ii) maintaining EAA bioavailability (AUC0-300 min) compared to a free AA mixture (Reference). Secondary endpoints included effects on plasma profiles of other AA groups and effects on several metabolic markers. Thirty subjects completed the study. Both co-primary endpoints were met: Cmax for EAAs was 27% lower with the Test product compared to the Reference product (ratio, 0.726, p < 0.0001); overall plasma EAA levels from the two AA mixtures was within the pre-specified bioequivalence range (AUC0-300min ratio, 0.890 (95% CI: 0.865, 0.915)). These findings were supported by the results of secondary endpoints. Prolongation of AA absorption was associated with modulation of several metabolic markers. It will be important to understand whether this can improve the long-term management of disorders of AA metabolism.
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Affiliation(s)
- Mika Scheinin
- CRST Oy, Itäinen Pitkäkatu 4B, FI-20520 Turku, Finland;
- Institute of Biomedicine, University of Turku and TYKSLAB, Turku University Hospital, Kiinamyllynkatu 4-8, FI-20520 Turku, Finland
- Correspondence: ; Tel.: +358-405-014762; Fax: +358-225-10046
| | - Anna Barassi
- APR Applied Pharma Research sa via Corti 5, CH-6828 Balerna, Switzerland; (A.B.); (G.R.)
| | - Jouni Junnila
- Oy 4Pharma Ltd., Arkadiankatu 7, FI-00100 Helsinki, Finland;
| | - Zsófia Lovró
- CRST Oy, Itäinen Pitkäkatu 4B, FI-20520 Turku, Finland;
- Institute of Biomedicine, University of Turku and TYKSLAB, Turku University Hospital, Kiinamyllynkatu 4-8, FI-20520 Turku, Finland
| | - Giorgio Reiner
- APR Applied Pharma Research sa via Corti 5, CH-6828 Balerna, Switzerland; (A.B.); (G.R.)
| | - Essi Sarkkinen
- Food and Nutrition, Oy Medfiles Ltd. (CRO), P. O. Box 1450, FI-70701 Kuopio, Finland;
| | - Anita MacDonald
- Dietetic Department, Birmingham Women’s and Children’s Hospital NHS Foundation Trust, Birmingham B4 6NH, UK;
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Vardy ERLC, MacDonald A, Ford S, Hofman DL. Phenylketonuria, co-morbidity, and ageing: A review. J Inherit Metab Dis 2020; 43:167-178. [PMID: 31675115 DOI: 10.1002/jimd.12186] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 10/27/2019] [Accepted: 10/28/2019] [Indexed: 12/17/2022]
Abstract
Phenylketonuria (PKU) is a metabolic condition which, left untreated, results in severe and irreversible brain damage. Newborn screening and the development of the low phenylalanine (Phe) diet have transformed the outcomes for people with PKU. Those who have benefited from early treatment are now approaching their fifth and sixth decade. It is therefore timely to consider multi-morbidity in PKU and the effects of ageing, in parallel with the wider benefits of emerging treatment options in addition to dietary relaxation. We have conducted the first literature review of co-morbidity and ageing in the context of PKU. Avenues explored have emerged from limited study of multi-morbidity to date and the knowledge and critical enquiry of the authors. Findings suggest PKU to have a wider impact than brain development, and result in several intriguing questions that require investigation to attain the best outcomes for people with PKU in adulthood moving through to older age. We recognise the difficulty in studying longitudinal outcomes in rare diseases and emphasise the necessity to develop PKU registries and cohorts that facilitate well-designed studies to answer some of the questions raised in this review. Whilst awaiting new information in these areas we propose that clinicians engage with patients to make personalised and well-informed decisions around Phe control and assessment for co-morbidity.
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Affiliation(s)
- Emma R L C Vardy
- Department of Ageing and Complex Medicine, Salford Royal NHS Foundation Trust, Salford Care Organisation, Part of Northern Care Alliance NHS Group, Salford, UK
| | - Anita MacDonald
- Department of dietetics, Birmingham Women's and Children's NHS Trust, Birmingham, UK
| | - Suzanne Ford
- National Society for Phenylketonuria, Preston, UK
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21
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Cannet C, Pilotto A, Rocha JC, Schäfer H, Spraul M, Berg D, Nawroth P, Kasperk C, Gramer G, Haas D, Piel D, Kölker S, Hoffmann G, Freisinger P, Trefz F. Lower plasma cholesterol, LDL-cholesterol and LDL-lipoprotein subclasses in adult phenylketonuria (PKU) patients compared to healthy controls: results of NMR metabolomics investigation. Orphanet J Rare Dis 2020; 15:61. [PMID: 32106880 PMCID: PMC7047385 DOI: 10.1186/s13023-020-1329-5] [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: 08/09/2019] [Accepted: 02/07/2020] [Indexed: 12/22/2022] Open
Abstract
Background Phenylketonuria (PKU; OMIM#261600) is a rare metabolic disorder caused by mutations in the phenylalanine hydroxylase (PAH) gene resulting in high phenylalanine (Phe) in blood and brain. If not treated early this results in intellectual disability, behavioral and psychiatric problems, microcephaly, motor deficits, eczematous rash, autism, seizures, and developmental problems. There is a controversial discussion of whether patients with PKU have an additional risk for atherosclerosis due to interference of Phe with cholesterol synthesis and LDL-cholesterol regulation. Since cholesterol also plays a role in membrane structure and myelination, better insight into the clinical significance of the impact of Phe on lipoprotein metabolism is desirable. In 22 treated PKU patients (mean age 38.7 years) and 14 healthy controls (mean age 35.2 years), we investigated plasma with NMR spectroscopy and quantified 105 lipoprotein parameters (including lipoprotein subclasses) and 24 low molecular weight parameters. Analysis was performed on a 600 MHz Bruker AVANCE IVDr spectrometer as previously described. Results Concurrent plasma Phe in PKU patients showed a wide range with a mean of 899 μmol/L (50–1318 μmol/L). Total cholesterol and LDL-cholesterol were significantly lower in PKU patients versus controls: 179.4 versus 200.9 mg/dL (p < 0.02) and 79.5 versus 104.1 mg/dL (p < 0.0038), respectively. PKU patients also had lower levels of 22 LDL subclasses with the greatest differences in LDL2 Apo-B, LDL2 Particle Number, LDL2-phospholipids, and LDL2-cholesterol (p < 0.0001). There was a slight negative correlation of total cholesterol and LDL-cholesterol with concurrent Phe level. VLDL5-free cholesterol, VLDL5-cholesterol, VLDL5-phospholipids, and VLDL4-free cholesterol showed a significant (p < 0.05) negative correlation with concurrent Phe level. There was no difference in HDL and their subclasses between PKU patients and controls. Tyrosine, glutamine, and creatinine were significantly lower in PKU patients compared to controls, while citric and glutamic acids were significantly higher. Conclusions Using NMR spectroscopy, a unique lipoprotein profile in PKU patients can be demonstrated which mimics a non-atherogenic profile as seen in patients treated by statins.
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Affiliation(s)
| | - Andrea Pilotto
- Department of Neurodegeneration, Hertie Institute of Clinical Brain Research, University of Tübingen, Tübingen, Germany.,Neurology Unit, Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy.,Parkinson's Disease Rehabilitation Centre, FERB ONLUS S, Isidoro Hospital, Trescore Balneario, Italy
| | - Júlio César Rocha
- Center for Health Technology and Services Research (CINTESIS), Porto, Portugal.,Nutrition & Metabolism, NOVA Medical School, Faculdade de Ciências Médicas, Universidade Nova de Lisboa, Lisbon, Portugal
| | | | | | - Daniela Berg
- Department of Neurology, University-Hospital-Schleswig-Holstein, Christian-Albrechts-University, Kiel, Germany
| | - Peter Nawroth
- Department of Endocrinology and Metabolism, University Hospital, Heidelberg, Germany
| | - Christian Kasperk
- Department of Endocrinology and Metabolism, University Hospital, Heidelberg, Germany
| | - Gwendolyn Gramer
- Department of Pediatrics, Centre for Pediatric and Adolescent Medicine, Division of Neuropaediatrics and Metabolic Medicine, University Hospital, Heidelberg, Germany
| | - Dorothea Haas
- Department of Pediatrics, Centre for Pediatric and Adolescent Medicine, Division of Neuropaediatrics and Metabolic Medicine, University Hospital, Heidelberg, Germany
| | - David Piel
- Pediatrics, Reutlingen Hospital, Reutlingen, Germany
| | - Stefan Kölker
- Department of Pediatrics, Centre for Pediatric and Adolescent Medicine, Division of Neuropaediatrics and Metabolic Medicine, University Hospital, Heidelberg, Germany
| | - Georg Hoffmann
- Department of Pediatrics, Centre for Pediatric and Adolescent Medicine, Division of Neuropaediatrics and Metabolic Medicine, University Hospital, Heidelberg, Germany
| | | | - Friedrich Trefz
- Department of Pediatrics, Centre for Pediatric and Adolescent Medicine, Division of Neuropaediatrics and Metabolic Medicine, University Hospital, Heidelberg, Germany. .,Metabolic Consulting, Reutlingen, Germany.
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22
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Harding CO. Prospects for Cell-Directed Curative Therapy of Phenylketonuria (PKU). MOLECULAR FRONTIERS JOURNAL 2019; 3:110-121. [PMID: 32524084 PMCID: PMC7286632 DOI: 10.1142/s2529732519400145] [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] [Indexed: 11/29/2022] Open
Abstract
Phenylketonuria (PKU) due to recessively inherited phenylalanine hydroxylase (PAH) deficiency is among the most common inborn errors of metabolism. Dietary therapy begun early in infancy prevents the major manifestations of the disease but shortcomings to treatment continue to exist including lifelong commitment to a complicated and unpalatable diet, poor adherence to diet in adolescence and adulthood, and consequently a range of unsatisfactory outcomes, including neuropsychiatric disorders, frequently develop. Novel treatments that do not strictly depend upon dietary protein restriction are actively sought. This review discusses the potential for and the limitations of permanently curative cell-directed treatment of PKU, including liver-directed gene therapy and gene editing, if initiated during early infancy. A fictional but realistic vignette of a family with a new baby girl recently diagnosed with PKU is presented. What is needed to permanently cure her?
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Affiliation(s)
- Cary O Harding
- Department of Molecular and Medical Genetics, Oregon Health & Science University, Mailstop L-103, 3181 Sam Jackson Park Rd., Portland, OR 97239, USA
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23
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Azabdaftari A, van der Giet M, Schuchardt M, Hennermann JB, Plöckinger U, Querfeld U. The cardiovascular phenotype of adult patients with phenylketonuria. Orphanet J Rare Dis 2019; 14:213. [PMID: 31492166 PMCID: PMC6731621 DOI: 10.1186/s13023-019-1188-0] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Accepted: 08/30/2019] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND Patients with Phenylketonuria (PKU) are exposed to multiple cardiovascular risk factors, but the clinical significance of these abnormalities is yet unknown. The purpose of this study was to characterize the cardiovascular phenotype in adult patients with PKU by clinical and dietary data, measurements of biochemical markers, and non-invasive examination of vascular functions. RESULTS Twenty-three adult patients with PKU (age: 18-47 y; 30.8 ± 8.4 y) and 28 healthy controls (age: 18-47 y; 30.1 ± 9.1 y) were included in this study. PKU patients had significantly higher systolic and diastolic blood pressure, increased resting heart rate and a higher body mass index. Total cholesterol and non-HDL cholesterol levels were significantly increased in PKU patients, whereas plasma levels of HDL cholesterol and its subfraction HDL2 (but not HDL3) were significantly decreased. The inflammatory markers C-reactive protein and serum amyloid A protein and the serum oxidative stress marker malondialdehyde were significantly higher in patients with PKU. Venous occlusion plethysmography showed marked reduction in post-ischemic blood flow and the carotid to femoral pulse wave velocity was significantly increased demonstrating endothelial dysfunction and increased vascular stiffness. CONCLUSIONS This study shows that the cardiovascular phenotype of adult PKU patients is characterized by an accumulation of traditional cardiovascular risk factors, high levels of inflammatory and oxidative stress markers, endothelial dysfunction and vascular stiffness. These data indicate the need for early cardiovascular risk reduction in patients with PKU.
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Affiliation(s)
- Aline Azabdaftari
- Department of Pediatrics, Division of Gastroenterology, Nephrology and Metabolic Diseases, Charité - Universitätsmedizin Berlin, Campus Virchow-Klinikum, Augstenburger Platz 1, 13353, Berlin, Germany
| | - Markus van der Giet
- Department of Nephrology, Charité - Universitätsmedizin Berlin, Campus Benjamin Franklin, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Mirjam Schuchardt
- Department of Nephrology, Charité - Universitätsmedizin Berlin, Campus Benjamin Franklin, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Julia B Hennermann
- Villa Metabolica, Department of Pediatric and Adolescent Medicine, University Medical Center Mainz, Langenbeckstr, 1, 55131, Mainz, Germany
| | - Ursula Plöckinger
- Interdisciplinary Center of Metabolism: Endocrinology, Diabetes and Metabolism, Charité - Universitätsmedizin Berlin, Campus Virchow-Klinikum, Augustenburger Platz 1, 13353, Berlin, Germany
| | - Uwe Querfeld
- Department of Pediatrics, Division of Gastroenterology, Nephrology and Metabolic Diseases, Charité - Universitätsmedizin Berlin, Campus Virchow-Klinikum, Augstenburger Platz 1, 13353, Berlin, Germany.
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24
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Trefz KF, Muntau AC, Kohlscheen KM, Altevers J, Jacob C, Braun S, Greiner W, Jha A, Jain M, Alvarez I, Lane P, Schröder C, Rutsch F. Clinical burden of illness in patients with phenylketonuria (PKU) and associated comorbidities - a retrospective study of German health insurance claims data. Orphanet J Rare Dis 2019; 14:181. [PMID: 31331350 PMCID: PMC6647060 DOI: 10.1186/s13023-019-1153-y] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Accepted: 07/03/2019] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND Phenylketonuria (PKU) is an inherited deficiency in the enzyme phenylalanine hydroxylase (PAH), which, when poorly-managed, is associated with clinical features including deficient growth, microcephaly, seizures, and intellectual impairment. The management of PKU should start as soon as possible after diagnosis to prevent irreversible damage and be maintained throughout life. The aim of this study was to assess the burden of illness in PKU patients in general and in PKU patients born before and after the introduction of newborn screening in Germany. METHODS This retrospective matched cohort analysis used the Institut für angewandte Gesundheitsforschung Berlin (InGef) research database containing anonymized healthcare claims of approximately 4 million covered lives. PKU patients were compared with matched controls from the general population within the same database (1:10 ratio via direct, exact matching on age and gender without replacement). PKU patients were included if they were aged ≥18 years on 01/01/15 and were continuously enrolled from 01/01/10 to 31/12/15. The 50 most commonly reported comorbidities and 50 most commonly prescribed medications in the PKU population were analyzed. Differences between groups were tested using 95% confidence interval (CI) of prevalence ratio (PR) values. RESULTS The analysis included 377 adult PKU patients (< 5 of which were receiving sapropterin dihydrochloride) and 3,770 matched controls. Of the 50 most common comorbidities in the PKU population, those with a statistically significant PR > 1.5 vs controls included major depressive disorders (PR = 2.3), chronic ischemic heart disease (PR = 1.7), asthma (PR = 1.7), dizziness and giddiness (PR = 1.8), unspecified diabetes mellitus (PR = 1.7), infectious gastroenteritis and colitis (PR = 1.7), and reaction to severe stress and adjustment disorders (PR = 1.6). The most commonly prescribed Anatomical Therapeutic Chemical (ATC) subcodes among PKU patients (vs the control population) are for systemic antibacterials (34.7% vs 32.8%), anti-inflammatory and antirheumatic (29.4% vs 27.5%), renin-angiotensin agents (30.0% vs 27.0%), acid-related disorders (29.4% vs 20.2%), and beta-blockers (24.9% vs 19.9%). CONCLUSION The overall clinical burden on patients with PKU is exacerbated by a significantly higher risk of numerous comorbidities and hence, prescribing of the requisite medication, both for recognized (e.g. major depressive disorders) and more unexpected comorbidities (e.g. ischemic heart disease).
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Affiliation(s)
- K F Trefz
- Zentrum für Kinder- und Jugendmedizin, Universitätsklinikum Heidelberg, Heidelberg, Germany
| | - A C Muntau
- University Children's Hospital, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | | | | | - C Jacob
- Xcenda GmbH, Hannover, Germany
| | - S Braun
- Xcenda GmbH, Hannover, Germany
| | - W Greiner
- Fakultät für Gesundheitswissenschaften, Universität Bielefeld, Bielefeld, Germany
| | - A Jha
- BioMarin Europe Ltd., London, UK
| | - M Jain
- BioMarin Europe Ltd., London, UK
| | | | - P Lane
- BioMarin Europe Ltd., London, UK
| | - C Schröder
- BioMarin Deutschland GmbH, Kronberg/Ts, Germany
| | - F Rutsch
- Kinder- und Jugendmedizin - Allgemeine Pädiatrie, Universitätsklinikum Münster, Münster, Germany.
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Ceberio L, Hermida Á, Venegas E, Arrieta F, Morales M, Forga M, Gonzalo M. Phenylketonuria in the adult patient. Expert Opin Orphan Drugs 2019. [DOI: 10.1080/21678707.2019.1633914] [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: 10/26/2022]
Affiliation(s)
- Leticia Ceberio
- Inborn metabolic disease unit, Internal Medicine Service, Hospital Universitario de Cruces, Baracaldo, Vizcaya, Spain
| | - Álvaro Hermida
- Unit of Diagnosis and Treatment of Congenital Metabolic Diseases, Internal Medicine Service, Hospital Clínico Universitario de Santiago, Santiago de Compostela, Spain
| | - Eva Venegas
- Endocrinology and Nutrition Service, C.U.S.R Congenital Metabolic Disease, Hospital Universitario Virgen del Rocío, Sevilla, Spain
| | - Francisco Arrieta
- Departament Endocrinology Metabolism and Nutrion, C.U.S.R Congenital Metabolic Disease, CIBER Physiopathology of Obesity and Nutrition (CIBERobn), Ramón y Cajal Health Research Institute (IRYCIS), Madrid, Spain
| | - Montserrat Morales
- Inborn Metabolic Disease Service, C.S.U.R of Congenital Metabolic Diseases, Internal Medicine Service, Hospital 12 de octubre, Madrid, Spain
| | - Maria Forga
- Endocrinology and Nutrition Department, Hospital Clinic, Barcelona, Spain
| | - Montserrat Gonzalo
- UGC Endocrinology and Nutrition, Hospital Regional Universitario de Málaga, Instituto de Biomedicina de Málaga (IBIMA) & CIBER de Diabetes y Enfermedades Metabólicas asociadas (CIBERDEM), Málaga, Spain
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Burton BK, Jones KB, Cederbaum S, Rohr F, Waisbren S, Irwin DE, Kim G, Lilienstein J, Alvarez I, Jurecki E, Levy H. Prevalence of comorbid conditions among adult patients diagnosed with phenylketonuria. Mol Genet Metab 2018; 125:228-234. [PMID: 30266197 DOI: 10.1016/j.ymgme.2018.09.006] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Revised: 08/23/2018] [Accepted: 09/10/2018] [Indexed: 11/28/2022]
Abstract
BACKGROUND Phenylalanine hydroxylase (PAH) deficiency, otherwise known as phenylketonuria (PKU), is an inborn error of metabolism that requires treatment to be initiated in the newborn period and continued throughout life. Due to the challenges of treatment adherence and the resulting cumulative effects of high and labile blood phenylalanine, PKU exerts a significant burden of disease. Retrospective studies using large databases allow for unique perspectives on comorbidities associated with rare diseases. An evaluation of comorbidities across various organ systems is warranted to understand the disease burden in adult patients. OBJECTIVES The aim of this insurance claim-based observational study was to assess the prevalence of comorbid conditions across various organ systems (e.g. dermatological, renal, respiratory, gastrointestinal, hematological, and others) among adult PKU patients compared with matched controls from the general population. METHODS This retrospective, case-controlled study selected patients from United States insurance claims databases from 1998 to 2014 using International Classification of Diseases, Ninth Revision (ICD-9) codes for diagnosis of PKU. The date of first diagnosis during the study period was index date and this was not necessarily the first time the patient was diagnosed with PKU. Cases were matched with a 1:5 ratio with general population (non-PKU controls) on age, sex, race, geographic location, duration of time in the database and insurance type. Prevalence and prevalence ratio (PR) calculations for comorbidities across various organ systems among adults (≥20 years old) with PKU were compared with the general population (non-PKU controls). The conditions were selected based on complications associated with PKU and feedback from clinicians treating PKU patients. RESULTS A total of 3691 PKU patients and 18,455 matched, non-PKU controls were selected, with an average age of 35 years. The mean healthcare costs incurred by the PKU patients during baseline, were approximately 4 times that of the controls ($4141 vs $1283; p < .0001). The prevalence rates of comorbidities across various organ systems during the follow-up period were significantly higher for those with PKU than in the control group. After adjusting for baseline characteristics, the adjusted prevalence ratios (PR) of 15 conditions studied (asthma, alopecia, urticaria, gallbladder disease, rhinitis, esophageal disorders, anemia, overweight, GERD, eczema, renal insufficiency, osteoporosis, gastritis/esophagitis and kidney calculus) were all above PR = 1.24 and significantly higher for the PKU cohort (p ≤ .001). The highest adjusted PR were for renal insufficiency with hypertension (PR [95% CI]: 2.20 [1.60-3.00]; p < .0001) and overweight (PR [95%CI]: 2.06 [1.85-2.30]; p < .0001). CONCLUSIONS The prevalence of selected comorbidities across several organ systems is significantly higher among PKU patients than for general population controls. Regular screening for common co-morbidities may be warranted as part of PKU management.
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Affiliation(s)
- Barbara K Burton
- Ann & Robert Lurie Children's Hospital, 225 E. Chicago Ave., Chicago, IL 60611, United States
| | - Kyle Bradford Jones
- University of Utah School of Medicine, Department of Family and Preventive Medicine, 375 Chipeta Way Ste A., Salt Lake City, UT 84108, United States
| | - Stephen Cederbaum
- University of California, Los Angeles, 635 Charles E Young Dr Los Angeles, CA 90095-7332, United States
| | - Fran Rohr
- Boston Children's Hospital and Harvard Medical School, 1 Autumn St., Rm #526, Boston, MA 02115, United States
| | - Susan Waisbren
- Boston Children's Hospital and Harvard Medical School, 1 Autumn Street, #525, Boston, MA 02115, United States
| | - Debra E Irwin
- Truven Health Analytics, An IBM Watson Health Company, 7700 Old Georgetown Rd, 6th Floor, Bethesda, MD 20814, United States
| | - Gilwan Kim
- Truven Health Analytics, An IBM Watson Health Company, 7700 Old Georgetown Rd, 6th Floor, Bethesda, MD 20814, United States
| | - Joshua Lilienstein
- BioMarin Pharmaceutical Inc., 105 Digital Drive, Novato, CA 94949, United States
| | - Ignacio Alvarez
- BioMarin Pharmaceutical Inc., 105 Digital Drive, Novato, CA 94949, United States
| | - Elaina Jurecki
- BioMarin Pharmaceutical Inc., 105 Digital Drive, Novato, CA 94949, United States.
| | - Harvey Levy
- Boston Children's Hospital and Harvard Medical School, 1 Autumn St., Rm #526, Boston, MA 02115, United States
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27
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Rocha JC, MacDonald A. Treatment options and dietary supplements for patients with phenylketonuria. Expert Opin Orphan Drugs 2018. [DOI: 10.1080/21678707.2018.1536541] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
- Júlio César Rocha
- Centro de Genética Médica, Centro Hospitalar do Porto - CHP, Porto, Portugal
- Faculdade de Ciências da Saúde, Universidade Fernando Pessoa, Porto, Portugal
- Center for Health Technology and Services Research (CINTESIS), Porto, Portugal
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28
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van Wegberg AMJ, MacDonald A, Ahring K, Bélanger-Quintana A, Blau N, Bosch AM, Burlina A, Campistol J, Feillet F, Giżewska M, Huijbregts SC, Kearney S, Leuzzi V, Maillot F, Muntau AC, van Rijn M, Trefz F, Walter JH, van Spronsen FJ. The complete European guidelines on phenylketonuria: diagnosis and treatment. Orphanet J Rare Dis 2017; 12:162. [PMID: 29025426 PMCID: PMC5639803 DOI: 10.1186/s13023-017-0685-2] [Citation(s) in RCA: 381] [Impact Index Per Article: 54.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Accepted: 07/11/2017] [Indexed: 12/22/2022] Open
Abstract
Phenylketonuria (PKU) is an autosomal recessive inborn error of phenylalanine metabolism caused by deficiency in the enzyme phenylalanine hydroxylase that converts phenylalanine into tyrosine. If left untreated, PKU results in increased phenylalanine concentrations in blood and brain, which cause severe intellectual disability, epilepsy and behavioural problems. PKU management differs widely across Europe and therefore these guidelines have been developed aiming to optimize and standardize PKU care. Professionals from 10 different European countries developed the guidelines according to the AGREE (Appraisal of Guidelines for Research and Evaluation) method. Literature search, critical appraisal and evidence grading were conducted according to the SIGN (Scottish Intercollegiate Guidelines Network) method. The Delphi-method was used when there was no or little evidence available. External consultants reviewed the guidelines. Using these methods 70 statements were formulated based on the highest quality evidence available. The level of evidence of most recommendations is C or D. Although study designs and patient numbers are sub-optimal, many statements are convincing, important and relevant. In addition, knowledge gaps are identified which require further research in order to direct better care for the future.
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Affiliation(s)
- A. M. J. van Wegberg
- Division of Metabolic Diseases, Beatrix Children’s Hospital, University Medical Center Groningen, PO BOX 30.001, 9700 RB Groningen, The Netherlands
| | - A. MacDonald
- Dietetic Department, Birmingham Children’s Hospital, Birmingham, UK
| | - K. Ahring
- Department of PKU, Kennedy Centre, Glostrup, Denmark
| | - A. Bélanger-Quintana
- Metabolic Diseases Unit, Department of Paediatrics, Hospital Ramon y Cajal Madrid, Madrid, Spain
| | - N. Blau
- University Children’s Hospital, Dietmar-Hoppe Metabolic Centre, Heidelberg, Germany
- University Children’s Hospital Zürich, Zürich, Switzerland
| | - A. M. Bosch
- Department of Paediatrics, Division of Metabolic Disorders, Academic Medical Centre, University Hospital of Amsterdam, Amsterdam, The Netherlands
| | - A. Burlina
- Division of Inherited Metabolic Diseases, Department of Paediatrics, University Hospital of Padova, Padova, Italy
| | - J. Campistol
- Neuropaediatrics Department, Hospital Sant Joan de Déu, Universitat de Barcelona, Barcelona, Spain
| | - F. Feillet
- Department of Paediatrics, Hôpital d’Enfants Brabois, CHU Nancy, Vandoeuvre les Nancy, France
| | - M. Giżewska
- Department of Paediatrics, Endocrinology, Diabetology, Metabolic Diseases and Cardiology of the Developmental Age, Pomeranian Medical University, Szczecin, Poland
| | - S. C. Huijbregts
- Department of Clinical Child and Adolescent Studies-Neurodevelopmental Disorders, Faculty of Social Sciences, Leiden University, Leiden, The Netherlands
| | - S. Kearney
- Clinical Psychology Department, Birmingham Children’s Hospital, Birmingham, UK
| | - V. Leuzzi
- Department of Paediatrics, Child Neurology and Psychiatry, Sapienza University of Rome, Via dei Sabelli 108, 00185 Rome, Italy
| | - F. Maillot
- CHRU de Tours, Université François Rabelais, INSERM U1069, Tours, France
| | - A. C. Muntau
- University Children’s Hospital, University Medical Centre Hamburg-Eppendorf, 20246 Hamburg, Germany
| | - M. van Rijn
- Division of Metabolic Diseases, Beatrix Children’s Hospital, University Medical Center Groningen, PO BOX 30.001, 9700 RB Groningen, The Netherlands
| | - F. Trefz
- Department of Paediatrics, University of Heidelberg, Heidelberg, Germany
| | - J. H. Walter
- Medicine, Manchester Academic Health Sciences Centre, Central Manchester University Hospitals NHS Foundation Trust, Manchester, UK
| | - F. J. van Spronsen
- Division of Metabolic Diseases, Beatrix Children’s Hospital, University Medical Center Groningen, PO BOX 30.001, 9700 RB Groningen, The Netherlands
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Rabah F, Al-Thihli K, El-Naggari M, Elnour IB. A child with phenylketonuria and focal segmental glomerulosclerosis, the bright side of proteinuria. Metab Brain Dis 2017; 32:1119-1121. [PMID: 28386663 DOI: 10.1007/s11011-017-9998-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2016] [Accepted: 03/20/2017] [Indexed: 01/25/2023]
Abstract
Phenylketonuria (PKU) is the most common inborn error of amino acid metabolism. Phenylalanine hydroxylase is the underlying deficient enzyme. If left untreated, growth failure, microcephaly, global developmental delay, seizures and severe intellectual impairment would characterize the clinical picture of PKU. On the other side of protein homeostasis lies nephrotic syndrome. It is a well-known quantitative defect due to significant proteinuria. Focal segmental glomerulosclerosis (FSGS) is a special congenital variant affecting children and adults. Hereby, we describe a three- year old male child who presented with generalized edema and global developmental delay. Investigations revealed PKU along with FSGS. We assume that congenital nephrosis ameliorated the picture of PKU, and had a salutary effect on the growth and development. Such coexistence between PKU and FSGS hasn't been described before.
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Affiliation(s)
- Fatma Rabah
- Child Health Department, Sultan Qaboos University Hospital, PO Box 38, Al-Khoud 123, Muscat, Oman.
| | - Khalid Al-Thihli
- Genetics Department, Genetic and Developmental Medicine Clinic, Sultan Qaboos University Hospital, Muscat, Oman
| | - Mohamed El-Naggari
- Child Health Department, Sultan Qaboos University Hospital, PO Box 38, Al-Khoud 123, Muscat, Oman
| | - Ibtisam B Elnour
- Child Health Department, Sultan Qaboos University Hospital, PO Box 38, Al-Khoud 123, Muscat, Oman
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Amino Acid Medical Foods Provide a High Dietary Acid Load and Increase Urinary Excretion of Renal Net Acid, Calcium, and Magnesium Compared with Glycomacropeptide Medical Foods in Phenylketonuria. J Nutr Metab 2017; 2017:1909101. [PMID: 28546877 PMCID: PMC5436062 DOI: 10.1155/2017/1909101] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Accepted: 04/10/2017] [Indexed: 12/31/2022] Open
Abstract
Background. Skeletal fragility is a complication of phenylketonuria (PKU). A diet containing amino acids compared with glycomacropeptide reduces bone size and strength in mice. Objective. We tested the hypothesis that amino acid medical foods (AA-MF) provide a high dietary acid load, subsequently increasing urinary excretion of renal net acid, calcium, and magnesium, compared to glycomacropeptide medical foods (GMP-MF). Design. In a crossover design, 8 participants with PKU (16-35 y) provided food records and 24-hr urine samples after consuming a low-Phe diet in combination with AA-MF and GMP-MF for 1-3 wks. We calculated potential renal acid load (PRAL) of AA-MF and GMP-MF and determined bone mineral density (BMD) measurements using dual X-ray absorptiometry. Results. AA-MF provided 1.5-2.5-fold higher PRAL and resulted in 3-fold greater renal net acid excretion compared to GMP-MF (p = 0.002). Dietary protein, calcium, and magnesium intake were similar. GMP-MF significantly reduced urinary excretion of calcium by 40% (p = 0.012) and magnesium by 30% (p = 0.029). Two participants had low BMD-for-age and trabecular bone scores, indicating microarchitectural degradation. Urinary calcium with AA-MF negatively correlated with L1-L4 BMD. Conclusion. Compared to GMP-MF, AA-MF increase dietary acid load, subsequently increasing urinary calcium and magnesium excretion, and likely contributing to skeletal fragility in PKU. The trial was registered at clinicaltrials.gov as NCT01428258.
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Nutritional status in patients with phenylketonuria using glycomacropeptide as their major protein source. Eur J Clin Nutr 2017; 71:1230-1234. [PMID: 28402322 DOI: 10.1038/ejcn.2017.38] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Revised: 02/23/2017] [Accepted: 02/24/2017] [Indexed: 01/10/2023]
Abstract
BACKGROUND/OBJECTIVES Low phenylalanine (PHE), glycomacropeptide-based protein substitute (GMP) is an alternative to traditional L-amino acid supplements (AA) used in the dietary management of phenylketonuria (PKU). In a retrospective, longitudinal study, we report the nutritional status of PKU patients taking AA and GMP. SUBJECTS/METHODS Eleven PKU patients aged 27±10 years (1 HPA, 4 mild and 6 classical PKU) on dietary treatment were evaluated (anthropometry, body composition, blood pressure measurements, biochemical markers including vitamin, mineral, lipids, carbohydrates and protein status/metabolism, and nutritional intake assessment) at two different annual reviews. The mean time taking AA was 13±5 months and GMP 13±7 months. Blood phenylalanine (PHE) and tyrosine (TYR) were analysed before and after GMP introduction. RESULTS Both GMP and AA protein substitutes provided similar protein equivalent intake (0.85 vs 0.75 g/kg/day, P=0.182). In the GMP group, it contributed 57% (27-100%) of the protein substitute intake (with AA delivering the rest of protein substitute intake), providing an additional 34±12 mg/day PHE. Nutritional intake, anthropometry and body composition measurements were similar in both the groups. Median blood PHE did not change (P=0.594), although values within target range improved (36 vs 46%), but this was not statistically significant. Mean blood TYR increased (52.0±19.2 vs 63.2±25.6 μmol/l, P=0.033), and all biochemical markers remained stable, except for a lower A1C haemoglobin (P=0.011). CONCLUSIONS Partial GMP contribution to total protein substitute intake did not affect nutritional status in patients with PKU. Blood PHE control was not adversely affected. The increased blood TYR after GMP introduction necessitates further study.
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Ney DM, Etzel MR. Designing medical foods for inherited metabolic disorders: why intact protein is superior to amino acids. Curr Opin Biotechnol 2017; 44:39-45. [DOI: 10.1016/j.copbio.2016.10.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Accepted: 10/22/2016] [Indexed: 01/22/2023]
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Daly A, Evans S, Chahal S, Santra S, MacDonald A. Glycomacropeptide in children with phenylketonuria: does its phenylalanine content affect blood phenylalanine control? J Hum Nutr Diet 2017; 30:515-523. [PMID: 28111827 DOI: 10.1111/jhn.12438] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
BACKGROUND In phenylketonuria (PKU), there are no data available for children with respect to evaluating casein glycomacropeptide (CGMP) as an alternative to phenylalanine-free protein substitutes [Phe-free L-amino acid (AA)]. CGMP contains a residual amount of phenylalanine, which may alter blood phenylalanine control. METHODS In a prospective 6-month pilot study, we investigated the effect on blood phenylalanine control of CGMP-amino acid (CGMP-AA) protein substitute in 22 PKU subjects (13 boys, nine girls), median age (range) 11 years (6-16 years). Twelve received CGMP-AA and nine received Phe-free L-AA, (1 CGMP-AA withdrawal). Subjects partially or wholly replaced Phe-free L-AA with CGMP-AA. If blood phenylalanine exceeded the target range, the CGMP-AA dose was reduced and replaced with Phe-free L-amino acids. The control group remained on Phe-free L-AAs. Phenylalanine, tyrosine and Phe : Tyr ratio concentrations were compared with the results for the previous year. RESULTS In the CGMP-AA group, there was a significant increase in blood phenylalanine concentrations (pre-study, 275 μmol L-1 ; CGMP-AA, 317 μmol L-1 ; P = 0.02), a decrease in tyrosine concentrations (pre-study, 50 μmol L-1 ; CGMP-AA, 40 μmol L-1 ; P = 0.03) and an increase in Phe : Tyr ratios (pre-study, Phe : Tyr 4.9:1; CGMP-AA, Phe : Tyr 8:1; P = 0.02). In the control group there was a non-significant fall in phenylalanine concentrations (pre-study 325μmol/L: study 280μmol/L [p = 0.9], and no significant changes for tyrosine or phe/tyr ratios [p = 0.9]. Children taking the CGMP-AA found it more acceptable to L-AA. CONCLUSIONS Blood phenylalanine control declined with CGMP-AA but, by titrating the dose of CGMP-AA, blood phenylalanine control remained within target range. The additional intake of phenylalanine may have contributed to the change in blood phenylalanine concentration. CGMP-AA use requires careful monitoring in children.
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Affiliation(s)
- A Daly
- Birmingham Children's Hospital, Dietetic Department, Birmingham, UK
| | - S Evans
- Birmingham Children's Hospital, Dietetic Department, Birmingham, UK
| | - S Chahal
- Birmingham Children's Hospital, Dietetic Department, Birmingham, UK
| | - S Santra
- IMD (Inherited metabolic department) Birmingham Children's Hospital, Birmingham, UK
| | - A MacDonald
- Birmingham Children's Hospital, Dietetic Department, Birmingham, UK
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Ney DM, Stroup BM, Clayton MK, Murali SG, Rice GM, Rohr F, Levy HL. Glycomacropeptide for nutritional management of phenylketonuria: a randomized, controlled, crossover trial. Am J Clin Nutr 2016; 104:334-45. [PMID: 27413125 PMCID: PMC4962165 DOI: 10.3945/ajcn.116.135293] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Accepted: 06/10/2016] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND To prevent cognitive impairment, phenylketonuria requires lifelong management of blood phenylalanine (Phe) concentration with a low-Phe diet. The diet restricts intake of Phe from natural proteins in combination with traditional amino acid medical foods (AA-MFs) or glycomacropeptide medical foods (GMP-MFs) that contain primarily intact protein and a small amount of Phe. OBJECTIVE We investigated the efficacy and safety of a low-Phe diet combined with GMP-MFs or AA-MFs providing the same quantity of protein equivalents in free-living subjects with phenylketonuria. DESIGN This 2-stage, randomized crossover trial included 30 early-treated phenylketonuria subjects (aged 15-49 y), 20 with classical and 10 with variant phenylketonuria. Subjects consumed, in random order for 3 wk each, their usual low-Phe diet combined with AA-MFs or GMP-MFs. The treatments were separated by a 3-wk washout with AA-MFs. Fasting plasma amino acid profiles, blood Phe concentrations, food records, and neuropsychological tests were obtained. RESULTS The frequency of medical food intake was higher with GMP-MFs than with AA-MFs. Subjects rated GMP-MFs as more acceptable than AA-MFs and noted improved gastrointestinal symptoms and less hunger with GMP-MFs. ANCOVA indicated no significant mean ± SE increase in plasma Phe (62 ± 40 μmol/L, P = 0.136), despite a significant increase in Phe intake from GMP-MFs (88 ± 6 mg Phe/d, P = 0.026). AA-MFs decreased plasma Phe (-85 ± 40 μmol/L, P = 0.044) with stable Phe intake. Blood concentrations of Phe across time were not significantly different (AA-MFs = 444 ± 34 μmol/L, GMP-MFs = 497 ± 34 μmol/L), suggesting similar Phe control. Results of the Behavior Rating Inventory of Executive Function were not significantly different. CONCLUSIONS GMP-MFs provide a safe and acceptable option for the nutritional management of phenylketonuria. The greater acceptability and fewer side effects noted with GMP-MFs than with AA-MFs may enhance dietary adherence for individuals with phenylketonuria. This trial was registered at www.clinicaltrials.gov as NCT01428258.
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Affiliation(s)
| | | | - Murray K Clayton
- Statistics, and Plant Pathology, University of Wisconsin-Madison, Madison, WI
| | | | - Gregory M Rice
- Waisman Center and Department of Pediatrics, University of Wisconsin School of Medicine and Public Health, Madison, WI; and
| | - Frances Rohr
- Division of Genetics and Genomics, Boston Children's Hospital, Harvard Medical School, Boston, MA
| | - Harvey L Levy
- Division of Genetics and Genomics, Boston Children's Hospital, Harvard Medical School, Boston, MA
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Sawin EA, De Wolfe TJ, Aktas B, Stroup BM, Murali SG, Steele JL, Ney DM. Glycomacropeptide is a prebiotic that reduces Desulfovibrio bacteria, increases cecal short-chain fatty acids, and is anti-inflammatory in mice. Am J Physiol Gastrointest Liver Physiol 2015; 309:G590-601. [PMID: 26251473 PMCID: PMC4593820 DOI: 10.1152/ajpgi.00211.2015] [Citation(s) in RCA: 125] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Accepted: 07/31/2015] [Indexed: 01/31/2023]
Abstract
Glycomacropeptide (GMP) is a 64-amino acid (AA) glycophosphopeptide with application to the nutritional management of phenylketonuria (PKU), obesity, and inflammatory bowel disease (IBD). GMP is a putative prebiotic based on extensive glycosylation with sialic acid, galactose, and galactosamine. Our objective was to determine the prebiotic properties of GMP by characterizing cecal and fecal microbiota populations, short-chain fatty acids (SCFA), and immune responses. Weanling PKU (Pah(enu2)) and wild-type (WT) C57Bl/6 mice were fed isoenergetic AA, GMP, or casein diets for 8 wk. The cecal content and feces were collected for microbial DNA extraction to perform 16S microbiota analysis by Ion Torrent PGM sequencing. SCFA were determined by gas chromatography, plasma cytokines via a Bio-Plex Pro assay, and splenocyte T cell populations by flow cytometry. Changes in cecal and fecal microbiota are primarily diet dependent. The GMP diet resulted in a reduction from 30-35 to 7% in Proteobacteria, genera Desulfovibrio, in both WT and PKU mice with genotype-dependent changes in Bacteroidetes or Firmicutes. Cecal concentrations of the SCFA acetate, propionate, and butyrate were increased with GMP. The percentage of stimulated spleen cells producing interferon-γ (IFN-γ) was significantly reduced in mice fed GMP compared with casein. In summary, plasma concentrations of IFN-γ, TNF-α, IL-1β, and IL-2 were reduced in mice fed GMP. GMP is a prebiotic based on reduction in Desulfovibrio, increased SCFA, and lower indexes of inflammation compared with casein and AA diets in mice. Functional foods made with GMP may be beneficial in the management of PKU, obesity, and IBD.
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Affiliation(s)
- Emily A. Sawin
- 1Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, Wisconsin; and
| | - Travis J. De Wolfe
- 2Department of Food Science, University of Wisconsin-Madison, Madison, Wisconsin
| | - Busra Aktas
- 2Department of Food Science, University of Wisconsin-Madison, Madison, Wisconsin
| | - Bridget M. Stroup
- 1Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, Wisconsin; and
| | - Sangita G. Murali
- 1Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, Wisconsin; and
| | - James L. Steele
- 2Department of Food Science, University of Wisconsin-Madison, Madison, Wisconsin
| | - Denise M. Ney
- 1Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, Wisconsin; and
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Aguiar A, Ahring K, Almeida MF, Assoun M, Belanger Quintana A, Bigot S, Bihet G, Blom Malmberg K, Burlina A, Bushueva T, Caris A, Chan H, Clark A, Clark S, Cochrane B, Corthouts K, Dalmau J, Dassy M, De Meyer A, Didycz B, Diels M, Dokupil K, Dubois S, Eftring K, Ekengren J, Ellerton C, Evans S, Faria A, Fischer A, Ford S, Freisinger P, Giżewska M, Gokmen-Ozel H, Gribben J, Gunden F, Heddrich-Ellerbrok M, Heiber S, Heidenborg C, Jankowski C, Janssen-Regelink R, Jones I, Jonkers C, Joerg-Streller M, Kaalund-Hansen K, Kiss E, Lammardo AM, Lang K, Lier D, Lilje R, Lowry S, Luyten K, MacDonald A, Meyer U, Moor D, Pal A, Robert M, Robertson L, Rocha JC, Rohde C, Ross K, Saruhan S, Sjöqvist E, Skeath R, Stoelen L, Ter Horst NM, Terry A, Timmer C, Tuncer N, Vande Kerckhove K, van der Ploeg L, van Rijn M, van Spronsen FJ, van Teeffelen-Heithoff A, van Wegberg A, van Wyk K, Vasconcelos C, Vitoria I, Wildgoose J, Webster D, White FJ, Zweers H. Practices in prescribing protein substitutes for PKU in Europe: No uniformity of approach. Mol Genet Metab 2015; 115:17-22. [PMID: 25862610 DOI: 10.1016/j.ymgme.2015.03.006] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Revised: 03/18/2015] [Accepted: 03/19/2015] [Indexed: 11/16/2022]
Abstract
BACKGROUND There appears little consensus concerning protein requirements in phenylketonuria (PKU). METHODS A questionnaire completed by 63 European and Turkish IMD centres from 18 countries collected data on prescribed total protein intake (natural/intact protein and phenylalanine-free protein substitute [PS]) by age, administration frequency and method, monitoring, and type of protein substitute. Data were analysed by European region using descriptive statistics. RESULTS The amount of total protein (from PS and natural/intact protein) varied according to the European region. Higher median amounts of total protein were prescribed in infants and children in Northern Europe (n=24 centres) (infants <1 year, >2-3g/kg/day; 1-3 years of age, >2-3 g/kg/day; 4-10 years of age, >1.5-2.5 g/kg/day) and Southern Europe (n=10 centres) (infants <1 year, 2.5 g/kg/day, 1-3 years of age, 2 g/kg/day; 4-10 years of age, 1.5-2 g/kg/day), than by Eastern Europe (n=4 centres) (infants <1 year, 2.5 g/kg/day, 1-3 years of age, >2-2.5 g/kg/day; 4-10 years of age, >1.5-2 g/kg/day) and with Western Europe (n=25 centres) giving the least (infants <1 year, >2-2.5 g/kg/day, 1-3 years of age, 1.5-2 g/kg/day; 4-10 years of age, 1-1.5 g/kg/day). Total protein prescription was similar in patients aged >10 years (1-1.5 g/kg/day) and maternal patients (1-1.5 g/kg/day). CONCLUSIONS The amounts of total protein prescribed varied between European countries and appeared to be influenced by geographical region. In PKU, all gave higher than the recommended 2007 WHO/FAO/UNU safe levels of protein intake for the general population.
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Affiliation(s)
- A Aguiar
- Hospital de Santo Espirito da Ilha Terceira, Portugal
| | - K Ahring
- Kennedy Centre, Department of Clinical Genetics, Rigshospitalet, University of Copenhagen, Glostrup, Denmark
| | - M F Almeida
- Centro de Genética Médica Doutor Jacinto de Magalhães, CHP EPE, Porto, Portugal; Multidisciplinary Unit for Biomedical Research, UMIB-FCT, Porto, Portugal
| | - M Assoun
- Service des Maladies Héréditaires du Métabolisme, Hospital Necker Enfants Malades, Paris, France
| | | | - S Bigot
- Centre Hospitalier Universitaire de Rennes, France
| | - G Bihet
- Centre Hospitalier Chrétien, Centre Pinocchio Liège, Belgium
| | | | - A Burlina
- Division of Inherited Metabolic Diseases, Department of Pediatrics, University Hospital of Padova, Italy
| | - T Bushueva
- Scientific Center of Children's Health, Moscow, Russian Federation
| | - A Caris
- Centre Wallon de Génétique Humaine, Maladies Métaboliques, CHU de Liège Sart-Tilman, Belgium
| | - H Chan
- Evelina London Children's Hospital, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - A Clark
- National Centre for Inherited Metabolic Disorders, Dublin, Ireland
| | - S Clark
- Addenbrooke's Hospital, Cambridge, UK
| | - B Cochrane
- Royal Hospital for Sick Children, Glasgow, Scotland, UK
| | - K Corthouts
- University Hospitals Leuven, Center of Metabolic Diseases, Leuven, Belgium
| | | | - M Dassy
- Cliniques Universitaires St Luc, Brussels, Belgium
| | - A De Meyer
- Center of Metabolic Diseases, University Hospital, Antwerp, Belgium
| | - B Didycz
- University Children's Hospital, Cracow, Poland
| | - M Diels
- University Hospitals Leuven, Center of Metabolic Diseases, ZOL, Genk, Belgium
| | - K Dokupil
- Dr. von Hauner Children's Hospital, Munich, Germany
| | - S Dubois
- Service des Maladies Héréditaires du Métabolisme, Hospital Necker Enfants Malades, Paris, France
| | - K Eftring
- Queen Silvia's Children Hospital, Gothenburg, Sweden
| | - J Ekengren
- Queen Silvia's Children Hospital, Gothenburg, Sweden
| | | | - S Evans
- Birmingham Children's Hospital, Birmingham, UK
| | - A Faria
- Hospital Pediatrico, Centro Hospitalar e Universitário de Coimbra, EPE, Portugal
| | - A Fischer
- Klinikum am Steinenberg, Klinik für Kinder- und Jugendmedizin Reutlingen, Germany
| | - S Ford
- North Bristol NHS Trust Southmead and Frenchay, UK
| | - P Freisinger
- Klinikum am Steinenberg, Klinik für Kinder- und Jugendmedizin Reutlingen, Germany
| | - M Giżewska
- Pomeranian Medical University, Szczecin, Poland
| | - H Gokmen-Ozel
- Haccettepe University Children's Hospital, Ankara, Turkey
| | - J Gribben
- Evelina London Children's Hospital, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - F Gunden
- Uludag University Medical Faculty, Bursa, Turkey
| | | | - S Heiber
- University Hospital, Basel, Switzerland
| | - C Heidenborg
- Karolinska University Hospital, Stockholm, Sweden
| | - C Jankowski
- University Hospitals Bristol NHS Foundation Trust, UK
| | | | - I Jones
- Center of Metabolic Diseases, University Hospital, Antwerp, Belgium
| | - C Jonkers
- Academic Medical Hospital, Amsterdam, Netherlands
| | - M Joerg-Streller
- Medical University of Innsbruck, Clinic for Pediatrics, Inherited Metabolic Disorders, Austria
| | | | - E Kiss
- Semmelweis University, Hungary
| | | | - K Lang
- Ninewells Hospital, Dundee, Scotland, UK
| | - D Lier
- Klinikum am Steinenberg, Klinik für Kinder- und Jugendmedizin Reutlingen, Germany
| | - R Lilje
- Oslo University Hospital Rikshospitalet, Norway
| | - S Lowry
- Sheffield Children's NHS Foundation Trust, Sheffield, UK
| | - K Luyten
- Center of Metabolic Diseases, University Hospital, Antwerp, Belgium
| | - A MacDonald
- Birmingham Children's Hospital, Birmingham, UK.
| | - U Meyer
- Clinic of Paediatric Kidney, Liver and Metabolic Diseases Medical School Hannover, Germany
| | - D Moor
- Kinderspital Zürich, Switzerland
| | - A Pal
- Akademiska University Hospital (Children's Centre), Sweden
| | - M Robert
- Hôpital Universitaire des Enfants, Reine Fabiola, Bruxelles, Belgium
| | | | - J C Rocha
- Centro de Genética Médica Doutor Jacinto de Magalhães, CHP EPE, Porto, Portugal; Faculdade de Ciências da Saúde, Universidade Fernando Pessoa, Porto, Portugal; Center for Health Technology and Services Research (CINTESIS), Portugal
| | - C Rohde
- Hospital for Children and Adolescents, University Hospitals, University of Leipzig, Germany
| | - K Ross
- Royal Aberdeen Children's Hospital, Scotland, UK
| | - S Saruhan
- Haccettepe University Children's Hospital, Ankara, Turkey
| | - E Sjöqvist
- Children's Hospital, University Hospital Skåne, Sweden
| | - R Skeath
- Great Ormond Street Hospital for Children NHS Trust, London, UK
| | - L Stoelen
- Oslo University Hospital Rikshospitalet, Norway
| | | | - A Terry
- Alderhey Children's Hospital, Liverpool, UK
| | | | - N Tuncer
- Dokuz Eylül University Nevvar-Salih İşgören Children Hospital, Turkey
| | - K Vande Kerckhove
- University Hospitals Leuven, Center of Metabolic Diseases, Leuven, Belgium
| | | | - M van Rijn
- University of Groningen, University Medical Center, Groningen, Netherlands
| | - F J van Spronsen
- University of Groningen, University Medical Center, Groningen, Netherlands
| | | | - A van Wegberg
- Radboud University Nijmegen Medical Centre, Netherlands
| | - K van Wyk
- Evelina London Children's Hospital, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - C Vasconcelos
- Centro Hospitalar São João - Unidade de Doenças Metabólicas, Porto, Portugal
| | | | | | - D Webster
- University Hospitals Bristol NHS Foundation Trust, UK
| | - F J White
- Central Manchester University Hospitals NHS Foundation Trust, Manchester, UK
| | - H Zweers
- Radboud University Nijmegen Medical Centre, Netherlands
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Abstract
Phenylketonuria (PKU) is an inborn error of metabolism of the amino acid phenylalanine. It is an autosomal recessive disorder with a rate of incidence of 1 in 10,000 in Caucasian populations. Mutations in the phenylalanine hydroxylase (PAH) gene are the major cause of PKU, due to the loss of the catalytic activity of the enzyme product PAH. Newborn screening for PKU allows early intervention, avoiding irreparable neurological damage and intellectual disability that would arise from untreated PKU. The current primary treatment of PKU is the limitation of dietary protein intake, which in the long term may be associated with poor compliance in some cases and other health problems due to malnutrition. The only alternative therapy currently approved is the supplementation of BH4, the requisite co-factor of PAH, in the orally-available form of sapropterin dihydrochloride. This treatment is not universally available, and is only effective for a proportion (estimated 30%) of PKU patients. Research into novel therapies for PKU has taken many different approaches to address the lack of PAH activity at the core of this disorder: enzyme replacement via virus-mediated gene transfer, transplantation of donor liver and recombinant PAH protein, enzyme substitution using phenylalanine ammonia lyase (PAL) to provide an alternative pathway for the metabolism of phenylalanine, and restoration of native PAH activity using chemical chaperones and nonsense read-through agents. It is hoped that continuing efforts into these studies will translate into a significant improvement in the physical outcome, as well as quality of life, for patients with PKU.
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Affiliation(s)
- Gladys Ho
- 1 Genetic Metabolic Disorders Research Unit; 2 Disciplines of Paediatrics and Child Health and 3 Genetic Medicine, University of Sydney, Sydney, NSW, Australia ; 4 Genetic Metabolic Disorders Service, Western Sydney Genetics Program, Children's Hospital at Westmead, Sydney, NSW, Australia
| | - John Christodoulou
- 1 Genetic Metabolic Disorders Research Unit; 2 Disciplines of Paediatrics and Child Health and 3 Genetic Medicine, University of Sydney, Sydney, NSW, Australia ; 4 Genetic Metabolic Disorders Service, Western Sydney Genetics Program, Children's Hospital at Westmead, Sydney, NSW, Australia
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Abstract
PURPOSE OF REVIEW The purpose is to discuss advances in the nutritional and pharmacological management of phenylketonuria (PKU). RECENT FINDINGS Glycomacropeptide (GMP), a whey protein produced during cheese production, is a low-phenylalanine (phe) intact protein that represents a new dietary alternative to synthetic amino acids for people with PKU. Skeletal fragility is a long-term complication of PKU that based on murine research, appears to result from both genetic and nutritional factors. Skeletal fragility in murine PKU is attenuated with the GMP diet, compared with an amino acid diet, allowing greater radial bone growth. Pharmacologic therapy with tetrahydrobiopterin, acting as a molecular chaperone for phenylalanine hydroxylase, increases tolerance to dietary phe in some individuals. Large neutral amino acids inhibit phe transport across the intestinal mucosa and blood-brain barrier, and are most effective for individuals unable to comply with the low-phe diet. SUMMARY Although a low-phe synthetic amino acid diet remains the mainstay of PKU management, new nutritional and pharmacological treatment options offer alternative approaches to maintain lifelong low phe concentrations. GMP medical foods provide an alternative to amino acid formula that may improve bone health, and tetrahydrobiopterin permits some individuals with PKU to increase tolerance to dietary phe. Further research is needed to characterize the long-term efficacy of these new approaches for PKU management.
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Affiliation(s)
- Denise M. Ney
- Department of Nutritional Sciences and Waisman Center, University of Wisconsin-Madison, Milwaukee
| | - Robert D. Blank
- Department of Medicine, Division of Endocrinology, Diabetes, and Clinical Nutrition, Medical College of Wisconsin, Milwaukee
| | - Karen E. Hansen
- Department of Medicine, Division of Rheumatology, School of Medicine and Public Health, University of Wisconsin, USA
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Hennermann JB, Querfeld U. Unknown pathomechanisms of renal impairment in PKU. J Inherit Metab Dis 2013; 36:1087-8. [PMID: 24043382 DOI: 10.1007/s10545-013-9652-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2013] [Revised: 08/15/2013] [Accepted: 08/23/2013] [Indexed: 11/26/2022]
Affiliation(s)
- Julia B Hennermann
- Department of Pediatric Endocrinology, Gastroenterology and Metabolic Diseases, Charité Universitätsmedizin Berlin, Berlin, Germany,
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Ney DM. Does the PKU diet contribute to impaired renal function? J Inherit Metab Dis 2013; 36:903-4. [PMID: 23653227 DOI: 10.1007/s10545-013-9615-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/15/2013] [Revised: 03/25/2013] [Accepted: 04/19/2013] [Indexed: 10/26/2022]
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