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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] [What about the content of this article? (0)] [Affiliation(s)] [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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Wang MW, Wu CJ, Zhang ZQ. Neurological and imaging phenotypes of adults with untreated phenylketonuria: new cases and literature review. J Neurol 2023:10.1007/s00415-023-11760-9. [PMID: 37162580 DOI: 10.1007/s00415-023-11760-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 05/02/2023] [Accepted: 05/04/2023] [Indexed: 05/11/2023]
Abstract
OBJECTIVES Phenylketonuria (PKU) is the most prevalent congenital disease of amino acid metabolism. Neurological manifestations usually complicate PKU in untreated adult patients. This study describes neurological and imaging phenotypes of adult patients with untreated PKU. METHODS We investigated a cohort of 320 unrelated adult patients with suspected genetic leukoencephalopathies using whole-exome sequencing (WES). We analyzed the phenotypic features of adult PKU patients in our cohort and summarized cases reported in the literature. RESULTS We identified 10 patients in our cohort and 12 patients in the literature, who presented with neurological manifestations and were diagnosed with PKU in adulthood. Approximately 60% of these patients had onset of clinical features in adulthood. The most common neurological symptoms of patients presenting in adulthood were cognitive disturbance and spastic paralysis, followed by vision loss, cerebellar ataxia, weakness of limbs, and seizure. This differed from that of patients presenting with PKU features in childhood, who consistently had mental retardation with various neurological complications emerging during a broad age range. Imaging findings were similar between patients presenting with clinical features in childhood compared with adulthood, comprising symmetric periventricular white matter hyperintense on T2-weighted imaging and diffusion-weighted imaging predominantly in the parietal and occipital lobes. Also, normal brain imaging and diffuse leukoencephalopathies were observed in both patient groups. CONCLUSION PKU with clinical features presenting in adulthood is an atypical subtype and should be considered during diagnosis of adults with neurological symptoms and leukoencephalopathy. DWI seems to be most helpful to distinguish patients with PKU. Additionally, we demonstrate that PKU constitutes a part (3.1%) of adult genetic leukoencephalopathies.
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Affiliation(s)
- Meng-Wen Wang
- Department of Neurology and Institute of Neurology, The First Affiliated Hospital of Fujian Medical University, Fuzhou, 350005, China
| | - Chu-Jun Wu
- Department of Neurology, Beijing Tiantan Hospital, National Clinical Research Center for Neurological Diseases, Capital Medical University, No.119 South 4Th Ring West Road, Fengtai District, Beijing, 100070, China
- China National Clinical Research Center for Neurological Diseases, Beijing, 100070, China
| | - Zai-Qiang Zhang
- Department of Neurology, Beijing Tiantan Hospital, National Clinical Research Center for Neurological Diseases, Capital Medical University, No.119 South 4Th Ring West Road, Fengtai District, Beijing, 100070, China.
- China National Clinical Research Center for Neurological Diseases, Beijing, 100070, China.
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Abstract
Hyperphenylalaninemia (HPA) is the most common amino acid metabolism defect in humans. It is an autosomal-recessive disorder of the phenylalanine (Phe) metabolism, in which high Phe concentrations and low tyrosine (Tyr) concentrations in the blood cause phenylketonuria (PKU), brain dysfunction, light pigmentation and musty odor. Newborn screening data of HPA have revealed that the prevalence varies worldwide, with an average of 1:10,000. Most cases of HPA result from phenylalanine hydroxylase (PAH) deficiency, while a small number of HPA are caused by defects in the tetrahydrobiopterin (BH4) metabolism and DnaJ heat shock protein family (Hsp40) member C12 (DNAJC12) deficiency. Currently, the molecular pathophysiology of the neuropathology associated with HPA remains incompletely understood. Dietary restriction of Phe has been highly successful, although outcomes are still suboptimal and patients find it difficult to adhere to the treatment. Pharmacological treatments, such as BH4 and phenylalanine ammonia lyase, are available. Gene therapy for HPA is still in development.
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Affiliation(s)
- Anqi Chen
- Department of Forensic Medicine, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai, China
| | - Yukun Pan
- Barbell Therapeutics Co. Ltd., Shanghai, China,*Correspondence: Yukun Pan, ; Jinzhong Chen,
| | - Jinzhong Chen
- State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai, China,*Correspondence: Yukun Pan, ; Jinzhong Chen,
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Abstract
Phenylketonuria (PKU; also known as phenylalanine hydroxylase (PAH) deficiency) is an autosomal recessive disorder of phenylalanine metabolism, in which especially high phenylalanine concentrations cause brain dysfunction. If untreated, this brain dysfunction results in severe intellectual disability, epilepsy and behavioural problems. The prevalence varies worldwide, with an average of about 1:10,000 newborns. Early diagnosis is based on newborn screening, and if treatment is started early and continued, intelligence is within normal limits with, on average, some suboptimal neurocognitive function. Dietary restriction of phenylalanine has been the mainstay of treatment for over 60 years and has been highly successful, although outcomes are still suboptimal and patients can find the treatment difficult to adhere to. Pharmacological treatments are available, such as tetrahydrobiopterin, which is effective in only a minority of patients (usually those with milder PKU), and pegylated phenylalanine ammonia lyase, which requires daily subcutaneous injections and causes adverse immune responses. Given the drawbacks of these approaches, other treatments are in development, such as mRNA and gene therapy. Even though PAH deficiency is the most common defect of amino acid metabolism in humans, brain dysfunction in individuals with PKU is still not well understood and further research is needed to facilitate development of pathophysiology-driven treatments.
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Affiliation(s)
- Francjan J van Spronsen
- Beatrix Children's Hospital, University Medical Centre Groningen, University of Groningen, Groningen, Netherlands.
| | - Nenad Blau
- University Children's Hospital in Zurich, Zurich, Switzerland
| | - Cary Harding
- Department of Molecular and Medical Genetics and Department of Pediatrics, Oregon Health & Science University, Oregon, USA
| | | | - Nicola Longo
- Department of Pediatrics, University of Utah, Salt Lake City, Utah, USA
| | - Annet M Bosch
- University of Amsterdam, Department of Pediatrics, Division of Metabolic Disorders, Emma Children's Hospital, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
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Chen HF, Rose AM, Waisbren S, Ahmad A, Prosser LA. Newborn Screening and Treatment of Phenylketonuria: Projected Health Outcomes and Cost-Effectiveness. Children (Basel) 2021; 8:381. [PMID: 34065950 DOI: 10.3390/children8050381] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 05/08/2021] [Accepted: 05/09/2021] [Indexed: 11/16/2022]
Abstract
The objective of this study was to evaluate the cost-effectiveness of newborn screening and treatment for phenylketonuria (PKU) in the context of new data on adherence to recommended diet treatment and a newly available drug treatment (sapropterin dihydrochloride). A computer simulation model was developed to project outcomes for a hypothetical cohort of newborns with PKU. Four strategies were compared: (1) clinical identification (CI) with diet treatment; (2) newborn screening (NBS) with diet treatment; (3) CI with diet and medication (sapropterin dihydrochloride); and (4) NBS with diet and medication. Data sources included published literature, primary data, and expert opinion. From a societal perspective, newborn screening with diet treatment had an incremental cost-effectiveness ratio of $6400/QALY compared to clinical identification with diet treatment. Adding medication to NBS with diet treatment resulted in an incremental cost-effectiveness ratio of more than $16,000,000/QALY. Uncertainty analyses did not substantially alter the cost-effectiveness results. Newborn screening for PKU with diet treatment yields a cost-effectiveness ratio lower than many other recommended childhood prevention programs even if adherence is lower than previously assumed. Adding medication yields cost-effectiveness results unlikely to be considered favorable. Future research should consider conditions under which sapropterin dihydrochloride would be more economically attractive.
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Chen S, Zhu M, Hao Y, Feng J, Zhang Y. Effect of Delayed Diagnosis of Phenylketonuria With Imaging Findings of Bilateral Diffuse Symmetric White Matter Lesions: A Case Report and Literature Review. Front Neurol 2019; 10:1040. [PMID: 31636599 PMCID: PMC6788382 DOI: 10.3389/fneur.2019.01040] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Accepted: 09/13/2019] [Indexed: 11/17/2022] Open
Abstract
Phenylketonuria is a hereditary metabolic disorder due to the deficiency of tetrahydrobiopterin or phenylalanine hydroxylase. Delayed diagnoses of it manifest a progressive irreversible neurological impairment in the early years of the disease. Guthrie test and tandem mass spectrometry aided in early detection and intervention of phenylketonuria, which significantly decreased the disability of patients as well as reducing the need for diagnosis in adults. This is a case report of a 60-year-old Asian man, characterized by severe visual-spatial disorders and bilateral diffuse symmetric white matter lesions on magnetic resonance imaging, who was diagnosed as phenylketonuria with his congenital mental retardation sibling. Heterozygous mutations exist in gene encoding PAH c.1068C>A and c.740G>T. During the diagnosis, we looked up at other late-onset genetic diseases considered to occur rarely but gradually revealed similar clinical manifestations and significant white matter lesions gaining importance in guiding to correct diagnosis and treatment. We made a comprehensive review of phenylketonuria and other inherited diseases with major prevalence in adulthood with prominent white matter involvement. Our study aims to help neurologists to improve recognition of metabolism-related leukoencephalopathies without neglect of the role of congenital genetic factors.
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Bruinenberg VM, van Vliet D, van der Goot E, Counotte DS, Kuhn M, van Spronsen FJ, van der Zee EA. Long-term dietary intervention with low Phe and/or a specific nutrient combination improve certain aspects of brain functioning in phenylketonuria (PKU). PLoS One 2019; 14:e0213391. [PMID: 30875376 PMCID: PMC6420157 DOI: 10.1371/journal.pone.0213391] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Accepted: 02/19/2019] [Indexed: 02/06/2023] Open
Abstract
INTRODUCTION In phenylketonuria (PKU), a gene mutation in the phenylalanine metabolic pathway causes accumulation of phenylalanine (Phe) in blood and brain. Although early introduction of a Phe-restricted diet can prevent severe symptoms from developing, patients who are diagnosed and treated early still experience deficits in cognitive functioning indicating shortcomings of current treatment. In the search for new and/or additional treatment strategies, a specific nutrient combination (SNC) was postulated to improve brain function in PKU. In this study, a long-term dietary intervention with a low-Phe diet, a specific combination of nutrients designed to improve brain function, or both concepts together was investigated in male and female BTBR PKU and WT mice. MATERIAL & METHODS 48 homozygous wild-types (WT, +/+) and 96 PKU BTBRPah2 (-/-) male and female mice received dietary interventions from postnatal day 31 till 10 months of age and were distributed in the following six groups: high Phe diet (WT C-HP, PKU C-HP), high Phe plus specific nutrient combination (WT SNC-HP, PKU SNC-HP), PKU low-Phe diet (PKU C-LP), and PKU low-Phe diet plus specific nutrient combination (PKU SNC- LP). Memory and motor function were tested at time points 3, 6, and 9 months after treatment initiation in the open field (OF), novel object recognition test (NOR), spatial object recognition test (SOR), and the balance beam (BB). At the end of the experiments, brain neurotransmitter concentrations were determined. RESULTS In the NOR, we found that PKU mice, despite being subjected to high Phe conditions, could master the task on all three time points when supplemented with SNC. Under low Phe conditions, PKU mice on control diet could master the NOR at all three time points, while PKU mice on the SNC supplemented diet could master the task at time points 6 and 9 months. SNC supplementation did not consistently influence the performance in the OF, SOR or BB in PKU mice. The low Phe diet was able to normalize concentrations of norepinephrine and serotonin; however, these neurotransmitters were not influenced by SNC supplementation. CONCLUSION This study demonstrates that both a long-lasting low Phe diet, the diet enriched with SNC, as well as the combined diet was able to ameliorate some, but not all of these PKU-induced abnormalities. Specifically, this study is the first long-term intervention study in BTBR PKU mice that shows that SNC supplementation can specifically improve novel object recognition.
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Affiliation(s)
- Vibeke M. Bruinenberg
- Molecular Neurobiology, GELIFES, University of Groningen, Groningen, The Netherlands
| | - Danique van Vliet
- Division of Metabolic Diseases, Beatrix Children’s Hospital, University Medical Center of Groningen, University of Groningen, Groningen, The Netherlands
| | - Els van der Goot
- Molecular Neurobiology, GELIFES, University of Groningen, Groningen, The Netherlands
| | | | | | - Francjan J. van Spronsen
- Division of Metabolic Diseases, Beatrix Children’s Hospital, University Medical Center of Groningen, University of Groningen, Groningen, The Netherlands
| | - Eddy A. van der Zee
- Molecular Neurobiology, GELIFES, University of Groningen, Groningen, The Netherlands
- * E-mail:
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Handoom B, Megdad E, Al-Qasabi D, Al Mesned M, Hawary R, Al-Nufiee S, Al-Hassnan Z, Alsayed MD, Eldali A. The effects of low protein products availability on growth parameters and metabolic control in selected amino acid metabolism disorders patients. Int J Pediatr Adolesc Med 2018; 5:60-68. [PMID: 30805535 PMCID: PMC6363253 DOI: 10.1016/j.ijpam.2018.04.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Revised: 04/19/2018] [Accepted: 04/22/2018] [Indexed: 10/25/2022]
Abstract
BACKGROUND In Saudi Arabia, a diet for life policy has been adopted in the management of amino acid metabolism disorders for years. However, the specially designed low protein products/medical foods - which are one of the important treatment tools - were not available up until several years ago in Saudi Arabia (SA). Our aim was to measure the compliance and quality of life in patients affected with these disorders followed in the metabolic nutrition clinic at King Faisal Specialist Hospital & Research Centre (KFSH&RC), Riyadh, SA. METHODOLOGY We used a non-randomized retrospective/prospective study which utilized the growth parameters, biochemical data of patients plus questionnaires collected from patients and their family/caregivers. A total of n = 182 patients affected with selected amino acid metabolism disorders were enrolled. Some were excluded n = 84 for various reasons. Sample analyzed were: Phenylketonuria (PKU) (44), Maple Syrup Urine Disease (MSUD) (30), Tyrosinemia (TYR) (17) and Homocystinuria (HCU) (7). Tandem Mass Spectrometry (TMS) used to quantitate plasma amino acid concentrations. Data was obtained using (COMPLE) Microsoft-Access which was designed by the metabolic nutrition clinic at KFSH&RC-Riyadh. Student's paired t-test was used to investigate relationship between variables. RESULTS The main findings were the improvement of selected amino acid levels pre and post the usage of medical foods. In PKU patients, the TMS Phenylalanine (PHE) levels post usage was significantly decreased (P value < .0001). This was also the case in MSUD patients with significant decrease in Leucine & Isoleucine levels (P value .0008) but not in Valine levels (P value .1148) as 36.7% of them received Valine supplements while enrolled in the study. CONCLUSION Low protein products availability was successful in improving outcomes for selected amino acid metabolic disorders. However, due to compliance issues and impracticality of the diet, the results were not significant in all enrolled patients.
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Affiliation(s)
- Bedour Handoom
- Nutrition Department, King Faisal Specialist Hospital & Research Centre (KFSH&RC), Riyadh, SA, USA
| | - Eman Megdad
- Nutrition Department, King Faisal Specialist Hospital & Research Centre (KFSH&RC), Riyadh, SA, USA
| | - Dana Al-Qasabi
- Nutrition Department, King Faisal Specialist Hospital & Research Centre (KFSH&RC), Riyadh, SA, USA
| | - Munirah Al Mesned
- Nutrition Department, King Faisal Specialist Hospital & Research Centre (KFSH&RC), Riyadh, SA, USA
| | - Reem Hawary
- Nutrition Department, King Faisal Specialist Hospital & Research Centre (KFSH&RC), Riyadh, SA, USA
| | - Samir Al-Nufiee
- Medical Genetic Department, Children Hospital Taif, Taif, SA, USA
| | - Zuhair Al-Hassnan
- Medical Genetic Deparmant, King Faisal Specialist Hospital & Research Centre (KFSH&RC), Riyadh, SA, USA
| | - Moeenaldeen Dia Alsayed
- Medical Genetic Deparmant, King Faisal Specialist Hospital & Research Centre (KFSH&RC), Riyadh, SA, USA
| | - Abdelmoneim Eldali
- Biostatistics Epidemiology & Scientific Computing Department, King Faisal Specialist Hospital & Research Centre (KFSH&RC), Riyadh, SA, USA
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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van Spronsen FJ, van Wegberg AM, 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, Trefz FK, van Rijn M, Walter JH, MacDonald A. Key European guidelines for the diagnosis and management of patients with phenylketonuria. Lancet Diabetes Endocrinol 2017; 5:743-756. [PMID: 28082082 DOI: 10.1016/s2213-8587(16)30320-5] [Citation(s) in RCA: 230] [Impact Index Per Article: 32.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Revised: 09/11/2016] [Accepted: 09/28/2016] [Indexed: 12/14/2022]
Abstract
We developed European guidelines to optimise phenylketonuria (PKU) care. To develop the guidelines, we did a literature search, critical appraisal, and evidence grading according to the Scottish Intercollegiate Guidelines Network method. We used the Delphi method when little or no evidence was available. From the 70 recommendations formulated, in this Review we describe ten that we deem as having the highest priority. Diet is the cornerstone of treatment, although some patients can benefit from tetrahydrobiopterin (BH4). Untreated blood phenylalanine concentrations determine management of people with PKU. No intervention is required if the blood phenylalanine concentration is less than 360 μmol/L. Treatment is recommended up to the age of 12 years if the phenylalanine blood concentration is between 360 μmol/L and 600 μmol/L, and lifelong treatment is recommended if the concentration is more than 600 μmol/L. For women trying to conceive and during pregnancy (maternal PKU), untreated phenylalanine blood concentrations of more than 360 μmol/L need to be reduced. Treatment target concentrations are as follows: 120-360 μmol/L for individuals aged 0-12 years and for maternal PKU, and 120-600 μmol/L for non-pregnant individuals older than 12 years. Minimum requirements for the management and follow-up of patients with PKU are scheduled according to age, adherence to treatment, and clinical status. Nutritional, clinical, and biochemical follow-up is necessary for all patients, regardless of therapy.
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Affiliation(s)
- Francjan J van Spronsen
- Division of Metabolic Diseases, Beatrix Children's Hospital, University Medical Center Groningen, University of Groningen, Groningen, Netherlands.
| | - Annemiek Mj van Wegberg
- Division of Metabolic Diseases, Beatrix Children's Hospital, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
| | - Kirsten Ahring
- Department of PKU, Kennedy Centre, Copenhagen University Hospital, Glostrup, Denmark
| | | | - Nenad Blau
- University Children's Hospital, Dietmar-Hoppe Metabolic Centre, Heidelberg, Germany; University Children's Hospital Zurich, Zurich, Switzerland
| | - Annet M Bosch
- Department of Paediatrics, Division of Metabolic Disorders, Academic Medical Centre, University Hospital of Amsterdam, Amsterdam, Netherlands
| | - Alberto Burlina
- Division of Inherited Metabolic Diseases, Department of Paediatrics, University Hospital of Padova, Padova, Italy
| | - Jaime Campistol
- Neuropaediatrics Department, Hospital Sant Joan de Déu, University of Barcelona, Barcelona, Spain
| | - Francois Feillet
- Department of Pediatrics, Hôpital d'Enfants Brabois, CHU Nancy, Vandoeuvre les Nancy, France
| | - Maria Giżewska
- Department of Pediatrics, Endocrinology, Diabetology, Metabolic Diseases and Cardiology of the Developmental Age, Pomeranian Medical University, Szczecin, Poland
| | - Stephan C Huijbregts
- Department of Clinical Child and Adolescent Studies-Neurodevelopmental Disorders, Faculty of Social Sciences, Leiden University, Leiden, Netherlands
| | - Shauna Kearney
- Clinical Psychology Department, Birmingham Children's Hospital, Birmingham, UK
| | - Vincenzo Leuzzi
- Department of Pediatrics, Child Neurology and Psychiatry, Sapienza University of Rome, Rome, Italy
| | - Francois Maillot
- Internal Medicine Service, CHRU de Tours, François Rabelais University, Tours, France
| | - Ania C Muntau
- University Children's Hospital, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Fritz K Trefz
- University Children's Hospital, Dietmar-Hoppe Metabolic Centre, Heidelberg, Germany
| | - Margreet van Rijn
- Department of Dietetics, Beatrix Children's Hospital, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
| | - John H Walter
- Manchester Academic Health Sciences Centre, Central Manchester University Hospitals NHS Foundation Trust, Manchester, UK
| | - Anita MacDonald
- Dietetic Department, Birmingham Children's Hospital, Birmingham, UK
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Giżewska M, MacDonald A, Bélanger-Quintana A, Burlina A, Cleary M, Coşkun T, Feillet F, Muntau AC, Trefz FK, van Spronsen FJ, Blau N. Diagnostic and management practices for phenylketonuria in 19 countries of the South and Eastern European Region: survey results. Eur J Pediatr 2016; 175:261-72. [PMID: 26350228 DOI: 10.1007/s00431-015-2622-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Revised: 08/10/2015] [Accepted: 08/14/2015] [Indexed: 01/17/2023]
Abstract
UNLABELLED To avoid potentially severe outcomes, phenylketonuria (PKU) must be detected as soon as possible after birth and managed with life-long treatment. A questionnaire-based survey was performed to document diagnosis and management practices for PKU in a region of Southern and Eastern Europe. Prevalence and management data were obtained from 37/59 (63 %) centres within 19/22 (86%) contacted countries (N = 8600 patients). The main results' analysis was based on completed questionnaires obtained from 31 centres (53%) within 15 countries (68%). A median of 10 % of patients per centre had been diagnosed after the newborn period. Metabolic dieticians and specialised adult PKU clinics were lacking in 36 and 84% of centres, respectively. In 26% of centres, treatment initiation was delayed until >15 days of life. Blood phenylalanine (Phe) thresholds to start treatment and upper Phe targets were inconsistent across centres. Ten percent of centres reported monitoring Phe every 2 weeks for pregnant women with PKU, which is insufficient to minimise risk of neonatal sequalae. Sapropterin dihydrochloride treatment was available in 48% of centres, with 24-h responsiveness tests most common (36%). Only one centre among the five countries lacking newborn screening provided a completed questionnaire. CONCLUSION Targeted efforts by health care professionals and governments are needed to optimise diagnostic and management approaches for PKU in Southern and Eastern Europe. WHAT IS KNOWN PKU must be detected early and optimally managed throughout life to avoid poor outcomes, yet newborn screening is not universal and diagnostic and management practices for PKU are known to vary widely between different centres and countries. Targeted efforts by health care professionals and governments are needed to optimise diagnostic and management approaches. WHAT IS NEW PKU management practices are documented in 19 South and Eastern European countries indicating a heterogeneous situation across the region. Key areas for improvement identified in surveyed centres include a need for comprehensive screening in all countries, increased number of metabolic dietitians and specialised adult PKU clinics, delayed time to treatment initiation, appropriate Phe thresholds, Phe targets and monitoring frequencies, and universal access to currently available treatment options.
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Grosse SD. Showing Value in Newborn Screening: Challenges in Quantifying the Effectiveness and Cost-Effectiveness of Early Detection of Phenylketonuria and Cystic Fibrosis. Healthcare (Basel) 2015; 3:1133-57. [PMID: 26702401 PMCID: PMC4686149 DOI: 10.3390/healthcare3041133] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Accepted: 11/05/2015] [Indexed: 01/24/2023] Open
Abstract
Decision makers sometimes request information on the cost savings, cost-effectiveness, or cost-benefit of public health programs. In practice, quantifying the health and economic benefits of population-level screening programs such as newborn screening (NBS) is challenging. It requires that one specify the frequencies of health outcomes and events, such as hospitalizations, for a cohort of children with a given condition under two different scenarios-with or without NBS. Such analyses also assume that everything else, including treatments, is the same between groups. Lack of comparable data for representative screened and unscreened cohorts that are exposed to the same treatments following diagnosis can result in either under- or over-statement of differences. Accordingly, the benefits of early detection may be understated or overstated. This paper illustrates these common problems through a review of past economic evaluations of screening for two historically significant conditions, phenylketonuria and cystic fibrosis. In both examples qualitative judgments about the value of prompt identification and early treatment to an affected child were more influential than specific numerical estimates of lives or costs saved.
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Affiliation(s)
- Scott D Grosse
- National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention, Atlanta, GA 30341, USA; ; Tel.: +1-404-498-3074
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Zerjav Tansek M, Groselj U, Angelkova N, Anton D, Baric I, Djordjevic M, Grimci L, Ivanova M, Kadam A, Kotori V, Maksic H, Marginean O, Margineanu O, Miljanovic O, Moldovanu F, Muresan M, Nanu M, Samardzic M, Sarnavka V, Savov A, Stojiljkovic M, Suzic B, Tincheva R, Tahirovic H, Toromanovic A, Usurelu N, Battelino T. Phenylketonuria screening and management in southeastern Europe - survey results from 11 countries. Orphanet J Rare Dis 2015; 10:68. [PMID: 26025111 PMCID: PMC4451731 DOI: 10.1186/s13023-015-0283-0] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Accepted: 05/12/2015] [Indexed: 08/30/2023] Open
Abstract
BACKGROUND We aimed to assess the current state of PKU screening and management in the region of southeastern Europe. METHODS A survey was performed involving all identified professionals responsible for the PKU management in the 11 countries from South-Eastern region of Europe (Albania, Bulgaria, Bosnia and Herzegovina, Croatia, Kosovo, Macedonia, Moldova, Montenegro, Romania, Serbia, Slovenia). The questionnaire was designed to assess the characteristics regarding PKU management in three main areas: nation-wide characteristics, PKU screening, and characteristics of the PKU management in the responding centre. It consisted of 56 questions. The distribution and collection of the questionnaires (via e-mail) was taking place from December 2013 to March 2014. RESULTS Responses from participants from 11 countries were included; the countries cumulative population is approx. 52.5 mio. PKU screening was not yet introduced in 4 of 11 countries. Reported PKU incidences ranged from 1/7325 to 1/39338 (and were not known for 5 countries). National PKU guidelines existed in 5 of 11 countries and 7 of 11 countries had PKU registry (registries included 40 to 194 patients). The number of PKU centers in each country varied from 1 to 6. Routine genetic diagnostics was reported in 4 of 11 countries. Most commonly used laboratory method to assess phenylalanine levels was fluorometric. Tetrahydrobiopterine was used in only 2 of 11 countries. Most frequently, pediatricians were caring for the patients. Dietitian was a member of PKU team in only 4 of 11 countries, while regular psychological assessments were performed in 6 of 11 countries. Patient's PKU society existed in 7 of 11 countries. CONCLUSIONS The region of southeastern Europe was facing certain important challenges of PKU screening and management. Neonatal PKU screening should be introduced throughout the region. Furthermore, PKU management was falling behind internationally established standards-of-care in many aspects.
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Affiliation(s)
- Mojca Zerjav Tansek
- University Children's Hospital Ljubljana, UMC Ljubljana, Ljubljana, Slovenia.
| | - Urh Groselj
- University Children's Hospital Ljubljana, UMC Ljubljana, Ljubljana, Slovenia.
| | | | - Dana Anton
- Clinical Hospital for Children "Sfanta Maria", Iasi, Romania.
| | - Ivo Baric
- Department of Pediatrics, University Hospital Center Zagreb, Zagreb, Croatia. .,School of Medicine, University of Zagreb, Zagreb, Croatia.
| | - Maja Djordjevic
- Mother and Child Health Care Institute of Serbia, Belgrade, Serbia.
| | - Lindita Grimci
- University Hospital Center "Mother Teresa", Tirana, Albania.
| | | | - Adil Kadam
- University Pediatric Hospital Sofia, Sofia, Bulgaria.
| | - Vjosa Kotori
- Pediatric Clinic, University Clinical Center Pristina, Pristina, Kosovo.
| | - Hajrija Maksic
- University Clinical Center Sarajevo, Sarajevo, Bosnia and Herzegovina.
| | | | | | - Olivera Miljanovic
- Institute for Sick Children, Clinical Center of Montenegro, Podgorica, Montenegro.
| | | | - Mariana Muresan
- Clinical Hospital for Children "Iuliu Hateganu", Cluj-Napoca, Romania.
| | - Michaela Nanu
- Mother and Child Health Care Institute "Alfred Rusescu", Bucharest, Romania.
| | - Mira Samardzic
- Institute for Sick Children, Clinical Center of Montenegro, Podgorica, Montenegro.
| | - Vladimir Sarnavka
- Department of Pediatrics, University Hospital Center Zagreb, Zagreb, Croatia.
| | | | - Maja Stojiljkovic
- Institute of Molecular Genetics and Genetic Engineering, University of Belgrade, Belgrade, Serbia.
| | - Biljana Suzic
- Children Hospital Banja Luka, Banja Luka, Republic of Srpska, Bosnia and Herzegovina.
| | | | - Husref Tahirovic
- Department of Medical Sciences, Academy of Sciences and Arts of Bosnia and Herzegovina, Sarajevo, Bosnia and Herzegovina.
| | - Alma Toromanovic
- Department of Pediatrics, University Clinical Center Tuzla, Tuzla, Bosnia and Herzegovina.
| | - Natalia Usurelu
- Institute of Mother and Child, Centre of Reproductive Health and Medical Genetics, Chisinau, Moldova.
| | - Tadej Battelino
- University Children's Hospital Ljubljana, UMC Ljubljana, Ljubljana, Slovenia. .,Department of Pediatrics, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia.
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Soleymani Z, Keramati N, Rohani F, Jalaei S. Factors influencing verbal intelligence and spoken language in children with phenylketonuria. Indian Pediatr 2015; 52:397-401. [DOI: 10.1007/s13312-015-0644-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Camp KM, Parisi MA, Acosta PB, Berry GT, Bilder DA, Blau N, Bodamer OA, Brosco JP, Brown CS, Burlina AB, Burton BK, Chang CS, Coates PM, Cunningham AC, Dobrowolski SF, Ferguson JH, Franklin TD, Frazier DM, Grange DK, Greene CL, Groft SC, Harding CO, Howell RR, Huntington KL, Hyatt-Knorr HD, Jevaji IP, Levy HL, Lichter-Konecki U, Lindegren ML, Lloyd-Puryear MA, Matalon K, MacDonald A, McPheeters ML, Mitchell JJ, Mofidi S, Moseley KD, Mueller CM, Mulberg AE, Nerurkar LS, Ogata BN, Pariser AR, Prasad S, Pridjian G, Rasmussen SA, Reddy UM, Rohr FJ, Singh RH, Sirrs SM, Stremer SE, Tagle DA, Thompson SM, Urv TK, Utz JR, van Spronsen F, Vockley J, Waisbren SE, Weglicki LS, White DA, Whitley CB, Wilfond BS, Yannicelli S, Young JM. Phenylketonuria Scientific Review Conference: state of the science and future research needs. Mol Genet Metab 2014; 112:87-122. [PMID: 24667081 DOI: 10.1016/j.ymgme.2014.02.013] [Citation(s) in RCA: 133] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2014] [Revised: 02/25/2014] [Accepted: 02/26/2014] [Indexed: 01/17/2023]
Abstract
New developments in the treatment and management of phenylketonuria (PKU) as well as advances in molecular testing have emerged since the National Institutes of Health 2000 PKU Consensus Statement was released. An NIH State-of-the-Science Conference was convened in 2012 to address new findings, particularly the use of the medication sapropterin to treat some individuals with PKU, and to develop a research agenda. Prior to the 2012 conference, five working groups of experts and public members met over a 1-year period. The working groups addressed the following: long-term outcomes and management across the lifespan; PKU and pregnancy; diet control and management; pharmacologic interventions; and molecular testing, new technologies, and epidemiologic considerations. In a parallel and independent activity, an Evidence-based Practice Center supported by the Agency for Healthcare Research and Quality conducted a systematic review of adjuvant treatments for PKU; its conclusions were presented at the conference. The conference included the findings of the working groups, panel discussions from industry and international perspectives, and presentations on topics such as emerging treatments for PKU, transitioning to adult care, and the U.S. Food and Drug Administration regulatory perspective. Over 85 experts participated in the conference through information gathering and/or as presenters during the conference, and they reached several important conclusions. The most serious neurological impairments in PKU are preventable with current dietary treatment approaches. However, a variety of more subtle physical, cognitive, and behavioral consequences of even well-controlled PKU are now recognized. The best outcomes in maternal PKU occur when blood phenylalanine (Phe) concentrations are maintained between 120 and 360 μmol/L before and during pregnancy. The dietary management treatment goal for individuals with PKU is a blood Phe concentration between 120 and 360 μmol/L. The use of genotype information in the newborn period may yield valuable insights about the severity of the condition for infants diagnosed before maximal Phe levels are achieved. While emerging and established genotype-phenotype correlations may transform our understanding of PKU, establishing correlations with intellectual outcomes is more challenging. Regarding the use of sapropterin in PKU, there are significant gaps in predicting response to treatment; at least half of those with PKU will have either minimal or no response. A coordinated approach to PKU treatment improves long-term outcomes for those with PKU and facilitates the conduct of research to improve diagnosis and treatment. New drugs that are safe, efficacious, and impact a larger proportion of individuals with PKU are needed. However, it is imperative that treatment guidelines and the decision processes for determining access to treatments be tied to a solid evidence base with rigorous standards for robust and consistent data collection. The process that preceded the PKU State-of-the-Science Conference, the conference itself, and the identification of a research agenda have facilitated the development of clinical practice guidelines by professional organizations and serve as a model for other inborn errors of metabolism.
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Affiliation(s)
- Kathryn M Camp
- Office of Dietary Supplements, National Institutes of Health, Bethesda, MD 20982, USA.
| | - Melissa A Parisi
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA.
| | | | - Gerard T Berry
- Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA.
| | - Deborah A Bilder
- Department of Psychiatry, University of Utah, Salt Lake City, UT 84108, USA.
| | - Nenad Blau
- University Children's Hospital, Heidelberg, Germany; University Children's Hospital, Zürich, Switzerland.
| | - Olaf A Bodamer
- University of Miami Miller School of Medicine, Miami, FL 33136, USA.
| | - Jeffrey P Brosco
- University of Miami Mailman Center for Child Development, Miami, FL 33101, USA.
| | | | | | - Barbara K Burton
- Ann and Robert H. Lurie Children's Hospital of Chicago, Chicago, IL 60611, USA.
| | - Christine S Chang
- Agency for Healthcare Research and Quality, Rockville, MD 20850, USA.
| | - Paul M Coates
- Office of Dietary Supplements, National Institutes of Health, Bethesda, MD 20982, USA.
| | - Amy C Cunningham
- Tulane University Medical School, Hayward Genetics Center, New Orleans, LA 70112, USA.
| | | | - John H Ferguson
- Office of Rare Diseases Research, National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD 20982, USA.
| | | | | | - Dorothy K Grange
- Washington University School of Medicine, St. Louis Children's Hospital, St. Louis, MO 63110, USA.
| | - Carol L Greene
- University of Maryland School of Medicine, Baltimore, MD 21201, USA.
| | - Stephen C Groft
- Office of Rare Diseases Research, National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD 20982, USA.
| | - Cary O Harding
- Oregon Health & Science University, Portland, OR 97239, USA.
| | - R Rodney Howell
- University of Miami Miller School of Medicine, Miami, FL 33136, USA.
| | | | - Henrietta D Hyatt-Knorr
- Office of Rare Diseases Research, National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD 20982, USA.
| | - Indira P Jevaji
- Office of Research on Women's Health, National Institutes of Health, Bethesda, MD 20817, USA.
| | - Harvey L Levy
- Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA.
| | - Uta Lichter-Konecki
- George Washington University, Children's National Medical Center, Washington, DC 20010, USA.
| | | | | | | | | | - Melissa L McPheeters
- Vanderbilt Evidence-based Practice Center, Institute for Medicine and Public Health, Nashville, TN 37203, USA.
| | - John J Mitchell
- McGill University Health Center, Montreal, Quebec H3H 1P3, Canada.
| | - Shideh Mofidi
- Maria Fareri Children's Hospital of Westchester Medical Center, Valhalla, NY 10595, USA.
| | - Kathryn D Moseley
- University of Southern California Keck School of Medicine, Los Angeles, CA 90033, USA.
| | - Christine M Mueller
- Office of Orphan Products Development, U.S. Food and Drug Administration, Silver Spring, MD 20993, USA.
| | - Andrew E Mulberg
- Center for Drug Evaluation and Research, U.S. Food and Drug Administration, Silver Spring, MD 20993, USA.
| | - Lata S Nerurkar
- Office of Rare Diseases Research, National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD 20982, USA.
| | - Beth N Ogata
- University of Washington, Seattle, WA 98195, USA.
| | - Anne R Pariser
- Center for Drug Evaluation and Research, U.S. Food and Drug Administration, Silver Spring, MD 20993, USA.
| | - Suyash Prasad
- BioMarin Pharmaceutical Inc., San Rafael, CA 94901, USA.
| | - Gabriella Pridjian
- Tulane University Medical School, Hayward Genetics Center, New Orleans, LA 70112, USA.
| | | | - Uma M Reddy
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA.
| | | | | | - Sandra M Sirrs
- Vancouver General Hospital, University of British Columbia, Vancouver V5Z 1M9, Canada.
| | | | - Danilo A Tagle
- National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Susan M Thompson
- The Children's Hospital at Westmead, Sydney, NSW 2145, Australia.
| | - Tiina K Urv
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Jeanine R Utz
- University of Minnesota, Minneapolis, MN 55455, USA.
| | - Francjan van Spronsen
- University of Groningen, University Medical Center of Groningen, Beatrix Children's Hospital, Netherlands.
| | - Jerry Vockley
- University of Pittsburgh, Pittsburgh, PA 15224, USA.
| | - Susan E Waisbren
- Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA.
| | - Linda S Weglicki
- National Institute of Nursing Research, National Institutes of Health, Bethesda, MD 20892, USA.
| | - Desirée A White
- Department of Psychology, Washington University, St. Louis, MO 63130, USA.
| | | | - Benjamin S Wilfond
- Seattle Children's Research Institute, University of Washington School of Medicine, Seattle, WA 98101, USA.
| | | | - Justin M Young
- The Young Face, Facial Plastic and Reconstructive Surgery, Cumming, GA 30041, USA.
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LEE HHC, MAK CM, Poon GWK, Wong KY, LAM CW. Cost-benefit analysis of Hyperphenylalaninemia Due to 6-Pyruvoyl-Tetrahydropterin Synthase (PTPS) Deficiency: For Consideration of Expanded Newborn Screening in Hong Kong. J Med Screen 2014; 21:61-70. [PMID: 24803483 DOI: 10.1177/0969141314533531] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Objectives To evaluate the cost-benefit of implementing an expanded newborn screening programme for hyperphenylalaninemias due to 6-pyruvoyl-tetrahydropterin synthase (PTPS) deficiency in Hong Kong. Setting Regional public hospitals in Hong Kong providing care for cases of inborn errors of metabolism. Methods Implementational and operational costs of a new expanded mass spectrometry-based newborn screening programme were estimated. Data on various medical expenditures for the mild and severe phenotypic subtypes were gathered from a case cohort diagnosed with PTPS deficiency from 2001 to 2009. Local incidence from a previously published study was used. Results Implementation and operational costs of an expanded newborn screening programme in Hong Kong were estimated at HKD 10,473,848 (USD 1,342,801) annually. Assuming a birthrate of 50,000 per year and an incidence of 1 in 29,542 live births, the medical costs and adjusted loss of workforce per year would be HKD 20,773,207 (USD 2,663,232). Overall the annual savings from implementing the programme would be HKD 9,632,750 (USD 1,234,968). Conclusions Our estimates show that implementation of an expanded newborn screening programme in Hong Kong is cost-effective, with a significant annual saving for public expenditure.
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Affiliation(s)
- Hencher Han-chih LEE
- Chemical Pathology Laboratory, Department of Pathology, Princess Margaret Hospital, Hong Kong SAR, China
| | - Chloe Miu MAK
- Chemical Pathology Laboratory, Department of Pathology, Princess Margaret Hospital, Hong Kong SAR, China
| | - Grace Wing-Kit Poon
- Department of Paediatrics and Adolescent Medicine, Queen Mary Hospital, Hong Kong SAR, China
| | - Kar-Yin Wong
- Department of Paediatrics and Adolescent Medicine, Queen Mary Hospital, Hong Kong SAR, China
| | - Ching-wan LAM
- Department of Pathology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
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Coppus AMW. People with intellectual disability: what do we know about adulthood and life expectancy? ACTA ACUST UNITED AC 2014; 18:6-16. [PMID: 23949824 DOI: 10.1002/ddrr.1123] [Citation(s) in RCA: 202] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2012] [Revised: 12/03/2012] [Accepted: 12/20/2012] [Indexed: 12/13/2022]
Abstract
Increases in the life expectancy of people with Intellectual Disability have followed similar trends to those found in the general population. With the exception of people with severe and multiple disabilities or Down syndrome, the life expectancy of this group now closely approximates with that of the general population. Middle and old age, which until 30 years ago were not recognized in this population, are now important parts of the life course of these individuals. Older adults with Intellectual Disabilities form a small, but significant and growing proportion of older people in the community. How these persons grow older and how symptoms and complications of the underlying cause of the Intellectual Disability will influence their life expectancy is of the utmost importance.
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Affiliation(s)
- A M W Coppus
- Dichterbij, Center for the Intellectually Disabled, Medical Center, Gennep, The Netherlands.
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Abstract
OBJETIVO: Descrever as características clínicas e demográficas dos pacientes com diagnóstico de hiperfenilalaninemia acompanhados no Serviço de Referência em Triagem Neonatal da Bahia. MÉTODOS: Estudo transversal de 99 famílias (111 afetados) com fenótipo bioquímico de hiperfenilalaninemia, com coleta de dados em prontuários e em banco de dados laboratorial, incluindo aspectos demográficos e clínicos. RESULTADOS: A incidência de hiperfenilalaninemia na Bahia foi de um caso a cada 16.334 nascidos vivos, com cobertura de 91%. Dentre os pacientes acompanhados, 82% foram diagnosticados pela triagem neonatal e, em 11 famílias, havia mais de um caso. O fenótipo clássico da fenilcetonúria foi diagnosticado em 63 (57%) pacientes. Entre os triados, a mediana de idade na primeira consulta foi 39,5 dias e, deles, 34% apresentavam sintomatologia nesse momento; nenhum com atraso no desenvolvimento neuropsicomotor. A consanguinidade foi descrita em 32% dos casos e houve predomínio de pacientes classificados como brancos (63%). Os pais tinham baixa escolaridade e baixa renda. Dos 417 municípios da Bahia, 15% apresentavam pelo menos um caso, com concentração na região nordeste (10%) e na capital do Estado (14%). CONCLUSÕES: Os resultados evidenciaram idade tardia ao início do tratamento, o que pode comprometer os resultados do programa. Observou-se também presença de consanguinidade e recorrência familiar, reforçando a importância da investigação familiar para diagnosticar indivíduos com deficiência mental de etiologia não esclarecida que podem se beneficiar de tratamento.
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Koura HM, Abdallah Ismail N, Kamel AF, Ahmed AM, Saad-Hussein A, Effat LK. A long-term study of bone mineral density in patients with phenylketonuria under diet therapy. Arch Med Sci 2011; 7:493-500. [PMID: 22295034 PMCID: PMC3258737 DOI: 10.5114/aoms.2011.23417] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2010] [Revised: 11/10/2010] [Accepted: 12/05/2010] [Indexed: 11/17/2022] Open
Abstract
INTRODUCTION Dietary control of classic phenylketonuria (PKU) needs restriction of natural proteins; adequate protein intake is achieved by adding low phenylalanine (phe) formulae. The adequacy of this diet for normal bone mineralization had not been sufficiently evaluated. Our aim was to evaluate and follow up bone mineral density (BMD) in children and adolescents with PKU within a 2-year time interval to assess the adequacy of a phenylalanine restricted diet for bone mineralization and to search for a possible relationship between BMD, dietary control and blood phenylalanine (phe) concentrations. MATERIAL AND METHODS Thirty-two patients with classic PKU (3-19 years) were evaluated for their bone mineral status using dual energy X-ray absorptiometry (DEXA) both at the beginning (baseline) and the end (follow-up) of the study. RESULTS Low BMD was detected in 31.25% at the start and in 6.25% of patients after 2 years follows-up. No relationship was found between BMD and the duration of diet compliance and phe level as well. CONCLUSIONS In this study the low BMD detected in our patients was both at baseline and follow-up independent of diet restriction. A yearly DEXA would be highly beneficial for early detection and treatment, thus preventing osteoporosis and decreasing the risk of fractures. We also suggest the importance of searching for new emerging therapies such as enzyme substitution or gene therapy as low protein diet compliance was not enough to maintain normal bone mineral density.
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Affiliation(s)
- Hala M. Koura
- Department of Pediatric, National Research Centre, Cairo, Egypt
| | | | - Ashraf F. Kamel
- Department of Pediatric, National Research Centre, Cairo, Egypt
| | - Azza M Ahmed
- Department of Pediatric, National Research Centre, Cairo, Egypt
| | - Amal Saad-Hussein
- Department of Environmental Research, National Research Centre, Cairo, Egypt
| | - Laila K. Effat
- Department of Molecular Genetic, National Research Centre, Cairo, Egypt
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González MJ, Gutiérrez AP, Gassió R, Fusté ME, Vilaseca MA, Campistol J. Neurological complications and behavioral problems in patients with phenylketonuria in a follow-up unit. Mol Genet Metab 2011; 104 Suppl:S73-9. [PMID: 21821452 DOI: 10.1016/j.ymgme.2011.07.015] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2011] [Revised: 07/14/2011] [Accepted: 07/14/2011] [Indexed: 11/30/2022]
Abstract
OBJECTIVE To investigate the relationship between neurological complications, neuroradiological findings, and behavioral problems, age at diagnosis and dietary control along the follow-up of the PKU patients in our metabolic unit. DESIGN Retrospective study of the PKU patients diagnosed and controlled in our unit from 1985 to 2010. METHODS Registry of patients in a database with 50 items filled in by review of the clinical histories. Statistical study of the data (SPSS, 19.0 version). RESULTS 121 patients were included (median age: 16.0, range 1 month-46 years). 76% of them were diagnosed through neonatal screening. 12.4% had mild-PKU, 19% moderate-PKU and 68.6% classic-PKU. 88.4% of patients were treated with a protein-restricted diet, and 11.6% with BH4. 97.7% of the early diagnosed patients had normal IQ, while 46.3% of late diagnosed patients had mental retardation, 28.5% were borderline and 25% had normal IQ. In early diagnosed patients, there was a significantly negative correlation between IQ [mean (SD) 100 (11.1)] and the index of dietary control during the first six years of life [median (range) 310 (105-992)] and that of the immediately past year [348 (106-1127)] (p < 0.0001). The proportion of patients with late diagnosis and neurological and behavioral problems was significantly higher than that of the early diagnosed ones (p < 0.001). The proportion of early diagnosed patients with neurological and behavioral problems who had good, intermediate or poor dietary control during the first 6 years of life and the immediately past year was significantly different (p < 0.001). CONCLUSIONS The results show the impact of early diagnosis and good dietary treatment on the IQ and on the percentage of neurological complications and behavioral problems in PKU patients.
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Affiliation(s)
- María J González
- Neuropediatrics Department, Hospital Universitari Sant Joan de Déu, Barcelona, Spain
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Murphy GH, Johnson SM, Amos A, Weetch E, Hoskin R, Fitzgerald B, Lilburn M, Robertson L, Lee P. Adults with untreated phenylketonuria: out of sight, out of mind. Br J Psychiatry 2008; 193:501-2. [PMID: 19043156 PMCID: PMC2802510 DOI: 10.1192/bjp.bp.107.045021] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2007] [Revised: 12/19/2007] [Accepted: 01/18/2008] [Indexed: 11/23/2022]
Abstract
Some people with phenylketonuria who were born before screening began were never treated and are still alive. Here we report that far fewer people with untreated phenylketonuria were detected than are thought to exist (about 2000). The majority of those traced had high support needs, challenging behaviour and other symptoms of phenylketonuria. No significant differences were found between those who had or had not tried the phenylalanine-restricted diet. A randomised controlled trial is required to examine the effect of trying the low-phenylalanine diet for people with untreated phenylketonuria.
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Amorim T, Gatto SP, Boa-Sorte N, Leite MEQ, Fontes MIMM, Barretto J, Acosta AX. Aspectos clínicos da fenilcetonúria em serviço de referência em triagem neonatal da Bahia. Rev Bras Saude Mater Infant 2005. [DOI: 10.1590/s1519-38292005000400009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJETIVOS: descrever as características clínicas dos pacientes com hiperfenilalaninemia acompanhados no Serviço de Referência em Triagem Neonatal (SRTN) do estado da Bahia. MÉTODOS: estudo descritivo transversal, tendo como amostra todos os pacientes com diagnóstico conhecido de Hiperfenilalaninemia residentes no estado da Bahia e acompanhados no SRTN até setembro de 2005. Tal população é composta de 46 famílias, num total de 51 pacientes. A análise dos dados foi descritiva, incluindo medidas de tendência central e dispersão. RESULTADOS: houve discreto predomínio do gênero feminino (52,9%). A maioria dos pacientes (78,4%) teve seu diagnóstico estabelecido através da triagem neonatal, tendo, portanto, tratamento precoce. Consangüinidade foi registrada em 32,6% das famílias. A média de início do tratamento entre os pacientes diagnosticados pela triagem neonatal foi de 56,6 37,8 dias, enquanto que entre os pacientes com diagnóstico tardio, foi de 7,1 anos. CONCLUSÕES: o estudo descreve um grupo de pacientes representativo de uma patologia incluída no Programa Nacional de Triagem Neonatal (PNTN), sendo, portanto, de relevância para a saúde pública. Entre os dados clínicos, chama a atenção a média de idade do início do tratamento, superior ao recomendado na literatura, alertando para a necessidade de um maior enfoque no diagnóstico precoce.
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Affiliation(s)
| | - Sara P.P. Gatto
- Fundação Bahiana para o Desenvolvimento das Ciências, Brasil
| | - Ney Boa-Sorte
- Fundação Bahiana para o Desenvolvimento das Ciências, Brasil
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Kalkanoğlu HS, Ahring KK, Sertkaya D, Møller LB, Romstad A, Mikkelsen I, Guldberg P, Lou HC, Güttler F. Behavioural effects of phenylalanine-free amino acid tablet supplementation in intellectually disabled adults with untreated phenylketonuria. Acta Paediatr 2005; 94:1218-22. [PMID: 16278987 DOI: 10.1111/j.1651-2227.2005.tb02078.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AIM To evaluate the effects of phenylalanine (Phe)-free essential amino acid (AA) tablets enriched in tyrosine and tryptophan on the performance of intellectually disabled adult patients with untreated phenylketonuria (PKU). METHODS Phe-free AA tablets and placebo tablets were administered to 19 untreated PKU subjects on a normal diet for 6 mo in a prospective double-blinded crossover study. The adaptive behaviour of the patients was tested prior to the study and at 6 and 12 mo after the start, using a simplified version of the Vineland Adaptive Behaviour Scale. For each sub-domain, the patients were rated either "0" (for poor performance) or "1" (for good performance). Neurological signs and symptoms and specific behavioural characteristics were recorded monthly by caretakers. Every 6 mo, neurological examination of the patients was performed, and the caretakers were interviewed. The statistical significance of the results was tested by means of the Fisher's exact and Wilcoxon tests. RESULTS The most significant changes were an improved concentration and the development of a meaningful smile, which were observed in 44% and 43% of the patients on AA tablet treatment, respectively, but not patients on placebo. Other important but less significant changes included increased awareness of external stimuli (63%) and less self-injury (43%), and 40% were smiling and laughing occasionally. The mean overall rating increased from an initial value of 6.3 to 10.1 in patients when on AA tablet treatment (p=0.002), and to 7.0 in patients when on placebo (p=0.068). The difference between active AA treatment and placebo was statistically significant (p=0.027). CONCLUSIONS This pilot study suggests that Phe-free AA tablets enriched in tyrosine and tryptophan may improve the quality of life in some intellectually disabled adults with untreated PKU.
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Affiliation(s)
- H Serap Kalkanoğlu
- Department of Paediatrics, Nutrition and Metabolism Unit, Hacettepe University, Ankara, Turkey
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Merrick J, Aspler S, Schwarz G. Phenylalanine-restricted diet should be life long. A case report on long-term follow-up of an adolescent with untreated phenylketonuria. Int J Adolesc Med Health 2003; 15:165-8. [PMID: 12955819 DOI: 10.1515/ijamh.2003.15.2.165] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/21/2023]
Abstract
The aim of this brief report is to stimulate a debate and to advocate life-long treatment with phenylalanine restricted diet to persons with phenylketonuria. We present a case of an adolescent male who today is a 65 year old with moderate mental retardation. He was previously observed as having severe challenging and self-injurious behaviour, sleeping disorder, hyperactivity, and masturbation. In the last year before reassessment he displayed loss of weight, muscle weakness resulting in wheelchair placement, upper respiratory infections, and fungal skin infections. After reassessment in 1998 the patient was started on treatment with a phenylalanine-restricted diet supplemented with vitamin B12, iron, and folic acid. At follow-up one year later the patient had regained his weight and was walking around freely. The challenging and self-injurious behaviour, and the masturbation, had ceased, and he was participating in social activities which he had previously not been able to participate in. At follow-up four years later he was still at this level of accomplishment. In general, this patient's quality of life had increased. We therefore recommend life-long treatment with phenylalanine restricted diet for persons with previously treated, and also for those with untreated, phenylketonuria.
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Affiliation(s)
- Joav Merrick
- National Institute of Child Health and Human Development, Division of Community Health, Department of Family Medicine, Ben Gurion University, Beer-Sheva, Israel.
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Camp K, Francis G, Shropshire L. Initiating a Phenylalanine-Controlled Diet in a 5-Year-Old Child Newly Diagnosed With Phenylketonuria (PKU): Management Dilemmas and Developmental Outcome. TOP CLIN NUTR 2003; 18:111-6. [DOI: 10.1097/00008486-200304000-00007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Abstract
A 25-year-old woman with mild hyperphenylalaninemia developed disabling depression and panic attacks. The mutations on the phenylalanine hydroxylase gene indicated that she might be responsive to tetrahydrobiopterin therapy. Mutation analyses were performed by the John F. Kennedy Institute in Glostrup, Denmark. The response to tetrahydrobiopterin therapy was impressive at an oral dose of 50 mg twice a day. A 25-year-old woman with mild hyperphenylalaninemia due to a PAH mutation of IVS12nt1g-->a/E390G has been treated for 1 year with BH4 therapy. A maintenance dosage of only 100 mg/day has resulted in significant improvement of depression and panic attacks, with discontinuation of psychotropic medication.
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Affiliation(s)
- Richard Koch
- Childrens Hospital of Los Angeles, USC School of Medicine, Los Angeles, California, USA.
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Abstract
The genetic implications for PKU are similar to those for any inherited disorder, but require an intimate knowledge of the dietary care required by these women. Unfortunately, today most women with PKU have discontinued dietary treatment by adulthood and find the restricted phe diet onerous and difficult. Fortunately, this is changing. "Diet for life" is the usual, although not yet universally, adopted practice today, but even so, there are women who conceive "off diet." This inhibits intellectual development of the fetus. If intensive services are provided for such women, fetal outcome can be improved by good blood phe control between 120 and 360 uM/L. Although prenatal diagnosis is available by fetal mutation studies, many women today resist the benefits of genetic counseling. Unfortunately, insurance companies often are unwilling to pay for such procedures as mutation analysis or the provision of low phe diets. Overall, public policy for the care of women with genetic disorders is in a state of flux and strong leadership is required to improve services.
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Affiliation(s)
- F de la Cruz
- Mental Retardation and Developmental Disabilities Branch, National Institute of Child Health and Human Development, Bethesda, Maryland, USA.
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Abstract
OBJECTIVES Clinicians caring for persons with phenylketonuria (PKU) have been perplexed by the occasional normal individual with the classical biochemical profile consistent with the diagnosis of PKU. Usually untreated subjects with the biochemical profile of blood phenylalanine (Phe) levels >1200 micromol/L are severely mentally retarded and may have neurological findings. Preliminary reports have recently appeared suggesting that low brain Phe levels, in comparison with elevated blood Phe levels, account for the occurrence of these occasional unaffected individuals with the biochemical profile consistent with PKU. METHOD Magnetic resonance imaging/magnetic resonance spectroscopy was used to measure brain Phe content compared with simultaneously obtained blood Phe levels determined on the amino acid analyzer. This comparison was obtained in 5 normal non-PKU persons, 4 carriers of the gene causing PKU, and in 29 individuals with the proven form of the disorder. RESULTS Blood-brain measurements in 5 normal persons ranged from.051 to.081 mmol/L, with a mean of.058 mmol/L. Their simultaneously measured brain levels of Phe ranged from.002 to.15 mmol/L, with a mean of.09 mmol/L. Similar measurements were obtained in 4 carriers of the gene causing PKU. Their blood levels varied between.068 and.109 mmol/L, with a mean of.091 mmol/L and simultaneously obtained brain levels of Phe varied between.06 and.21 mmol/L, with a mean of.11 mmol/L. Twenty subjects with a mean IQ of 104 exhibited a mean blood level of 1.428 mmol/L and a simultaneous mean brain level of.23 mmol/L, whereas 9 persons with a mean IQ of 98.7 exhibited a mean blood Phe level of 1.424 and a mean brain Phe level of.64 mmol/L. The correlation between blood and brain levels was not significant. CONCLUSION In usual cases, intellectually normal persons who have never been treated but who have a biochemical profile consistent with classical PKU exhibit lower brain levels of Phe. Such individuals are exceptional and may not need the vigorous restriction of their blood Phe levels that is required by the majority of persons with PKU.
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Affiliation(s)
- R Koch
- Department of Pediatrics and Radiology, Childrens Hospital of Los Angeles and the University of Southern California School of Medicine, Los Angeles, California 90027, USA.
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