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Upadia J, Crivelly K, Noh G, Cunningham A, Cerminaro C, Li Y, Mckoin M, Chenevert M, Andersson HC. Maximal dietary responsiveness after tetrahydrobiopterin (BH4) in 19 phenylalanine hydroxylase deficiency patients: What super-responders can expect. Mol Genet Metab Rep 2024; 38:101050. [PMID: 38469087 PMCID: PMC10926188 DOI: 10.1016/j.ymgmr.2024.101050] [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: 01/04/2024] [Accepted: 01/05/2024] [Indexed: 03/13/2024] Open
Abstract
Background Inherited phenylalanine hydroxylase deficiency, also known as phenylketonuria (PKU), causes poor growth and neurologic deficits in the untreated state. After ascertainment through newborn screen and dietary phenylalanine (Phe) restriction to achieve plasma Phe in the range of 120-360 μmol/L, these disease manifestations can be prevented. Poor compliance with protein restricted diets supported by medical food is typical in later years, beginning in the late toddler and teenage years. Pharmacologic doses of oral tetrahydrobiopterin (BH4; sapropterin dihydrochloride) is effective in reducing plasma Phe in about 40-50% of PKU patients but effectiveness is highly variable. Objective To assess the maximal responsiveness to 20 mg/kg/day oral BH4 as it affects plasma Phe and dietary Phe allowance in PKU patients. Materials and methods This was a single-center, retrospective observational study, combining case reports of individual patients. We reported an outcome of 85 patients with PKU who were trialed on BH4. Phe levels and dietary records of 19 BH4 "super-responders" were analyzed. Results Overall, 63.5% of the patients (54/85) were considered BH4 responders. However, we quantitated the dietary liberalization of 19 of our responsive patients (35%), those with at least a 2-fold increase in dietary Phe and maintenance of plasma Phe in treatment range. In these "super-responders", the mean plasma Phe at baseline was 371 ± 237 μmol/L and decreased to 284 ± 273 μmol/L after 1 year on BH4. Mean dietary Phe tolerance increased significantly from 595 ± 256 to 2260 ± 1414 mg/day (p ≤0.0001), while maintaining mean plasma Phe levels within treatment range. Four patients no longer required dietary Phe restriction and could discontinue medical food. The majority of patients had at least one BH4-responsive genotype. Conclusion This cohort demonstrates the maximally achievable dietary liberalization which some PKU patients may expect with BH4 therapy. Health benefits are considered to accrue in patients with increased intact protein.
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Affiliation(s)
- Jariya Upadia
- Hayward Genetics Center, New Orleans, LA 70112, USA
- Department of Pediatrics, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Kea Crivelly
- Hayward Genetics Center, New Orleans, LA 70112, USA
- Department of Pediatrics, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Grace Noh
- Hayward Genetics Center, New Orleans, LA 70112, USA
- Department of Pediatrics, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Amy Cunningham
- Hayward Genetics Center, New Orleans, LA 70112, USA
- Department of Pediatrics, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Caroline Cerminaro
- Hayward Genetics Center, New Orleans, LA 70112, USA
- Department of Pediatrics, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Yuwen Li
- Hayward Genetics Center, New Orleans, LA 70112, USA
- Department of Pediatrics, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Meredith Mckoin
- Hayward Genetics Center, New Orleans, LA 70112, USA
- Department of Pediatrics, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Madeline Chenevert
- Hayward Genetics Center, New Orleans, LA 70112, USA
- Department of Pediatrics, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Hans C. Andersson
- Hayward Genetics Center, New Orleans, LA 70112, USA
- Department of Pediatrics, Tulane University School of Medicine, New Orleans, LA 70112, USA
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Evers RAF, van Wegberg AMJ, MacDonald A, Huijbregts SCJ, Leuzzi V, van Spronsen FJ. Dietary Liberalization in Tetrahydrobiopterin-Treated PKU Patients: Does It Improve Outcomes? Nutrients 2022; 14:nu14183874. [PMID: 36145250 PMCID: PMC9504284 DOI: 10.3390/nu14183874] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Revised: 08/30/2022] [Accepted: 09/01/2022] [Indexed: 11/23/2022] Open
Abstract
Purpose: this systematic review aimed to assess the effects of dietary liberalization following tetrahydrobiopterin (BH4) treatment on anthropometric measurements, nutritional biomarkers, quality of life, bone density, mental health and psychosocial functioning, and burden of care in PKU patients. Methods: the PubMed, Cochrane, and Embase databases were searched on 7 April 2022. We included studies that reported on the aforementioned domains before and after dietary liberalization as a result of BH4 treatment in PKU patients. Exclusion criteria were: studies written in a language other than English; studies that only included data of a BH4 loading test; insufficient data for the parameters of interest; and wrong publication type. Both within-subject and between-subject analyses were assessed, and meta-analyses were performed if possible. Results: twelve studies containing 14 cohorts and 228 patients were included. Single studies reported few significant differences. Two out of fifteen primary meta-analyses were significant; BMI was higher in BH4-treated patients versus controls (p = 0.02; standardized mean difference (SMD) (95% confidence interval (CI)) = −0.37 (−0.67, −0.06)), and blood cholesterol concentrations increased after starting BH4 treatment (p = 0.01; SMD (CI) = −0.70 (−1.26, −0.15)). Conclusion: there is no clear evidence that dietary liberalization after BH4 treatment has a positive effect on anthropometric measurements, nutritional biomarkers, or quality of life. No studies could be included for bone density, mental health and psychosocial functioning, and burden of care.
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Affiliation(s)
- Roeland A. F. Evers
- Division of Metabolic Diseases, Beatrix Children’s Hospital, University Medical Center Groningen, 9700 RB Groningen, The Netherlands
| | - Annemiek M. J. van Wegberg
- Division of Metabolic Diseases, Beatrix Children’s Hospital, University Medical Center Groningen, 9700 RB Groningen, The Netherlands
| | - Anita MacDonald
- Dietetic Department, Birmingham Children’s Hospital, Birmingham B4 6NH, UK
| | - Stephan C. J. Huijbregts
- Department of Clinical Child and Adolescent Studies-Neurodevelopmental Disorders, Faculty of Social Sciences, Leiden University, 2300 RB Leiden, The Netherlands
| | - Vincenzo Leuzzi
- Unit of Child Neurology and Psychiatry, Department of Human Neuroscience, Sapienza University of Rome, 00185 Rome, Italy
| | - Francjan J. van Spronsen
- Division of Metabolic Diseases, Beatrix Children’s Hospital, University Medical Center Groningen, 9700 RB Groningen, The Netherlands
- Correspondence: ; Tel.: +31-(0)50-3614147
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Bensi G, Carbone MT, Schiaffino MC, Parolisi S, Pozzoli A, Biasucci G. Quality of life aspects of a low protein diet using GMP in patients with phenylketonuria. J Int Med Res 2022; 50:3000605221125524. [PMID: 36146893 PMCID: PMC9511328 DOI: 10.1177/03000605221125524] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Objective To assess some quality of life (QOL) aspects of a low protein diet, using glycomacropeptide (GMP) as a protein substitute in patients with phenylketonuria (PKU). Methods This was a multicentre, prospective observational cohort, study. Metabolic control, nutritional parameters, and dietary adherence were assessed in patients with PKU before (T0), and six months after (T6) starting a low protein diet using GMP. Selected items from the PKU-QOL questionnaire were used to assess patients’ acceptance of their modified diet. Results 18 patients from three Italian Centres, completed the study. With the exception of LDL-cholesterol and vitamin 25OH-D concentrations, there were no differences between T0 and T6 in metabolic or nutritional parameters. Data suggested that patients have a good acceptance of protein substitutes containing GMP, probably because of their improved palatability. Conclusions According to our patients’ responses to items related to dietary regimen, GMP based protein substitutes do not appear to significantly affect QOL.
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Affiliation(s)
- Giulia Bensi
- Paediatrics & Neonatology Unit, Guglielmo da Saliceto Hospital, Piacenza, Italy
| | | | - Maria Cristina Schiaffino
- Paediatrics and Endocrinology Unit, Giannina Gaslini Children's Hospital and Research Institute, Genoa, Italy
| | - Sara Parolisi
- Rare and Metabolic Diseases Unit, AORN Santobono-Pausilipon, Naples, Italy
| | - Angela Pozzoli
- Paediatrics & Neonatology Unit, Guglielmo da Saliceto Hospital, Piacenza, Italy
| | - Giacomo Biasucci
- Paediatrics & Neonatology Unit, Guglielmo da Saliceto Hospital, Piacenza, Italy
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Adolfsen KJ, Callihan I, Monahan CE, Greisen PJ, Spoonamore J, Momin M, Fitch LE, Castillo MJ, Weng L, Renaud L, Weile CJ, Konieczka JH, Mirabella T, Abin-Fuentes A, Lawrence AG, Isabella VM. Improvement of a synthetic live bacterial therapeutic for phenylketonuria with biosensor-enabled enzyme engineering. Nat Commun 2021; 12:6215. [PMID: 34711827 PMCID: PMC8553829 DOI: 10.1038/s41467-021-26524-0] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 10/12/2021] [Indexed: 11/09/2022] Open
Abstract
In phenylketonuria (PKU) patients, a genetic defect in the enzyme phenylalanine hydroxylase (PAH) leads to elevated systemic phenylalanine (Phe), which can result in severe neurological impairment. As a treatment for PKU, Escherichia coli Nissle (EcN) strain SYNB1618 was developed under Synlogic's Synthetic Biotic™ platform to degrade Phe from within the gastrointestinal (GI) tract. This clinical-stage engineered strain expresses the Phe-metabolizing enzyme phenylalanine ammonia lyase (PAL), catalyzing the deamination of Phe to the non-toxic product trans-cinnamate (TCA). In the present work, we generate a more potent EcN-based PKU strain through optimization of whole cell PAL activity, using biosensor-based high-throughput screening of mutant PAL libraries. A lead enzyme candidate from this screen is used in the construction of SYNB1934, a chromosomally integrated strain containing the additional Phe-metabolizing and biosafety features found in SYNB1618. Head-to-head, SYNB1934 demonstrates an approximate two-fold increase in in vivo PAL activity compared to SYNB1618.
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Affiliation(s)
- Kristin J Adolfsen
- Zymergen Inc. (formerly enEvolv Inc.), 100 Acorn Park Drive, Cambridge, MA, 02140, USA
| | - Isolde Callihan
- Zymergen Inc. (formerly enEvolv Inc.), 100 Acorn Park Drive, Cambridge, MA, 02140, USA
| | | | - Per Jr Greisen
- Zymergen Inc. (formerly enEvolv Inc.), 100 Acorn Park Drive, Cambridge, MA, 02140, USA
- Novo Nordisk Research Center Seattle Inc, 530 Fairview Ave N, Seattle, WA, 98109, USA
| | - James Spoonamore
- Zymergen Inc. (formerly enEvolv Inc.), 100 Acorn Park Drive, Cambridge, MA, 02140, USA
| | - Munira Momin
- Synlogic Inc, 301 Binney St, Cambridge, MA, 02139, USA
| | - Lauren E Fitch
- Zymergen Inc. (formerly enEvolv Inc.), 100 Acorn Park Drive, Cambridge, MA, 02140, USA
| | | | - Lindong Weng
- Zymergen Inc. (formerly enEvolv Inc.), 100 Acorn Park Drive, Cambridge, MA, 02140, USA
- Sana Biotechnology, 1 Tower Place Suite 500, South San Francisco, CA, 94080, USA
| | - Lauren Renaud
- Synlogic Inc, 301 Binney St, Cambridge, MA, 02139, USA
| | - Carl J Weile
- Zymergen Inc. (formerly enEvolv Inc.), 100 Acorn Park Drive, Cambridge, MA, 02140, USA
| | - Jay H Konieczka
- Zymergen Inc. (formerly enEvolv Inc.), 100 Acorn Park Drive, Cambridge, MA, 02140, USA
| | | | | | - Adam G Lawrence
- Zymergen Inc. (formerly enEvolv Inc.), 100 Acorn Park Drive, Cambridge, MA, 02140, USA
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Ilgaz F, Marsaux C, Pinto A, Singh R, Rohde C, Karabulut E, Gökmen-Özel H, Kuhn M, MacDonald A. Protein Substitute Requirements of Patients with Phenylketonuria on BH4 Treatment: A Systematic Review and Meta-Analysis. Nutrients 2021; 13:1040. [PMID: 33807079 PMCID: PMC8004763 DOI: 10.3390/nu13031040] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Revised: 03/12/2021] [Accepted: 03/19/2021] [Indexed: 11/16/2022] Open
Abstract
The traditional treatment for phenylketonuria (PKU) is a phenylalanine (Phe)-restricted diet, supplemented with a Phe-free/low-Phe protein substitute. Pharmaceutical treatment with synthetic tetrahydrobiopterin (BH4), an enzyme cofactor, allows a patient subgroup to relax their diet. However, dietary protocols guiding the adjustments of protein equivalent intake from protein substitute with BH4 treatment are lacking. We systematically reviewed protein substitute usage with long-term BH4 therapy. Electronic databases were searched for articles published between January 2000 and March 2020. Eighteen studies (306 PKU patients) were eligible. Meta-analyses demonstrated a significant increase in Phe and natural protein intakes and a significant decrease in protein equivalent intake from protein substitute with cofactor therapy. Protein substitute could be discontinued in 51% of responsive patients, but was still required in 49%, despite improvement in Phe tolerance. Normal growth was maintained, but micronutrient deficiency was observed with BH4 treatment. A systematic protocol to increase natural protein intake while reducing protein substitute dose should be followed to ensure protein and micronutrient requirements are met and sustained. We propose recommendations to guide healthcare professionals when adjusting dietary prescriptions of PKU patients on BH4. Studies investigating new therapeutic options in PKU should systematically collect data on protein substitute and natural protein intakes, as well as other nutritional factors.
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Affiliation(s)
- Fatma Ilgaz
- Department of Nutrition and Dietetics, Faculty of Health Sciences, Hacettepe University, 06100 Ankara, Turkey; (F.I.); (H.G.-Ö.)
| | - Cyril Marsaux
- Danone Nutricia Research, 3584CT Utrecht, The Netherlands;
| | - Alex Pinto
- Department of Dietetics, Birmingham Women’s and Children’s Hospital, Birmingham B4 6NH, UK; (A.P.); (A.M.)
| | - Rani Singh
- Metabolic Genetics Nutrition Program, Department of Human Genetics, Emory University, Atlanta, GA 30322, USA;
| | - Carmen Rohde
- Department of Paediatrics of the University Clinics Leipzig, University of Leipzig, 04103 Leipzig, Germany;
| | - Erdem Karabulut
- Department of Biostatistics, Faculty of Medicine, Hacettepe University, 06100 Ankara, Turkey;
| | - Hülya Gökmen-Özel
- Department of Nutrition and Dietetics, Faculty of Health Sciences, Hacettepe University, 06100 Ankara, Turkey; (F.I.); (H.G.-Ö.)
| | - Mirjam Kuhn
- Danone Nutricia Research, 3584CT Utrecht, The Netherlands;
| | - Anita MacDonald
- Department of Dietetics, Birmingham Women’s and Children’s Hospital, Birmingham B4 6NH, UK; (A.P.); (A.M.)
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Hydery T, Coppenrath VA. A Comprehensive Review of Pegvaliase, an Enzyme Substitution Therapy for the Treatment of Phenylketonuria. Drug Target Insights 2019; 13:1177392819857089. [PMID: 31258325 PMCID: PMC6589953 DOI: 10.1177/1177392819857089] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Accepted: 05/23/2019] [Indexed: 11/16/2022] Open
Affiliation(s)
- Tasmina Hydery
- Department of Family Medicine and Community Health, UMass Medical School—Clinical Pharmacy Services (CPS), Shrewsbury, MA, USA
| | - Valerie Azzopardi Coppenrath
- School of Pharmacy—Worcester/Manchester, Massachusetts College of Pharmacy and Health Sciences (MCPHS) University, Worcester, MA, USA
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7
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Qu J, Yang T, Wang E, Li M, Chen C, Ma L, Zhou Y, Cui Y. Efficacy and safety of sapropterin dihydrochloride in patients with phenylketonuria: A meta-analysis of randomized controlled trials. Br J Clin Pharmacol 2019; 85:893-899. [PMID: 30720885 PMCID: PMC6475685 DOI: 10.1111/bcp.13886] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Revised: 01/08/2019] [Accepted: 01/19/2019] [Indexed: 12/22/2022] Open
Abstract
AIMS The aim of the present meta-analysis was to evaluate the efficacy and safety of sapropterin dihydrochloride in phenylketonuria (PKU) patients. METHODS The following databases were searched for randomized controlled trials (RCT) regarding PKU patients treated with sapropterin dihydrochloride: PubMed, Embase, Cochrane Library and clinicaltrials. Two authors independently selected studies, assessed the risk of bias and extracted data. The meta-analysis was performed in RevMan 5.3 provided by the Cochrane Collaboration. RESULTS Four studies met the inclusion criteria. In PKU patients with low blood phenylalanine (Phe) concentration, no significant difference was indicated for the decrease of Phe level (weighted mean difference (WMD) = -7.75 μmol L-1 ; 95% confidence intervals (CI): -82.63 to 67.13, P = 0.84, I2 = 0%), however, the dietary Phe tolerance was significantly improved in the sapropterin group (WMD = 19.89 mg kg-1 d-1 ; 95% CI: 10.26 to 29.52, P < 0.0001, I2 = 0%). In PKU patients with high blood Phe level, sapropterin showed a significant lowering in blood Phe concentration (WMD = -225.31 μmol L-1 ; 95% CI: -312.28 to -138.34, P < 0.00001, I2 = 0%). There was no significant difference for adverse events. CONCLUSIONS Sapropterin could bring benefit for PKU patients with high or low Phe level, due to Phe reduction in a short time or dietary Phe tolerance improvement respectively. Sapropterin has an acceptable safety profile.
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Affiliation(s)
- Jinghan Qu
- Department of PharmacyPeking University First Hospital8 Xishiku Street, Xicheng DistrictBeijing100034China
- Department of Pharmacy Administration and Clinical Pharmacy, School of Pharmaceutical SciencesPeking University Health Science Center38 Xueyuan Rd, Haidian District100191China
| | - Ting Yang
- Department of PharmacyPeking University First Hospital8 Xishiku Street, Xicheng DistrictBeijing100034China
| | - Ente Wang
- Department of PharmacyPeking University First Hospital8 Xishiku Street, Xicheng DistrictBeijing100034China
- Department of Pharmacy Administration and Clinical Pharmacy, School of Pharmaceutical SciencesPeking University Health Science Center38 Xueyuan Rd, Haidian District100191China
| | - Min Li
- Department of PharmacyPeking University First Hospital8 Xishiku Street, Xicheng DistrictBeijing100034China
- Department of Pharmacy Administration and Clinical Pharmacy, School of Pharmaceutical SciencesPeking University Health Science Center38 Xueyuan Rd, Haidian District100191China
| | - Chaoyang Chen
- Department of PharmacyPeking University First Hospital8 Xishiku Street, Xicheng DistrictBeijing100034China
| | - Lingyun Ma
- Department of PharmacyPeking University First Hospital8 Xishiku Street, Xicheng DistrictBeijing100034China
| | - Ying Zhou
- Department of PharmacyPeking University First Hospital8 Xishiku Street, Xicheng DistrictBeijing100034China
- Department of Pharmacy Administration and Clinical Pharmacy, School of Pharmaceutical SciencesPeking University Health Science Center38 Xueyuan Rd, Haidian District100191China
| | - Yimin Cui
- Department of PharmacyPeking University First Hospital8 Xishiku Street, Xicheng DistrictBeijing100034China
- Department of Pharmacy Administration and Clinical Pharmacy, School of Pharmaceutical SciencesPeking University Health Science Center38 Xueyuan Rd, Haidian District100191China
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Vieira Neto E, Laranjeira F, Quelhas D, Ribeiro I, Seabra A, Mineiro N, Carvalho LM, Lacerda L, Ribeiro MG. Genotype-phenotype correlations and BH 4 estimated responsiveness in patients with phenylketonuria from Rio de Janeiro, Southeast Brazil. Mol Genet Genomic Med 2019; 7:e610. [PMID: 30829006 PMCID: PMC6503030 DOI: 10.1002/mgg3.610] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Revised: 01/15/2019] [Accepted: 01/24/2019] [Indexed: 01/15/2023] Open
Abstract
BACKGROUND Genetic heterogeneity and compound heterozygosis give rise to a continuous spectrum of phenylalanine hydroxylase deficiency and metabolic phenotypes in phenylketonuria (PKU). The most used parameters for evaluating phenotype in PKU are pretreatment phenylalanine (Phe) levels, tolerance for dietary Phe, and Phe overloading test. Phenotype can vary from a "classic" (severe) form to mild hyperphenylalaninemia, which does not require dietary treatment. A subset of patients is responsive to treatment by the cofactor tetrahydrobiopterin (BH4 ). Genotypes of PKU patients from Rio de Janeiro, Brazil, were compared to predicted and observed phenotypes. Genotype-based estimations of responsiveness to BH4 were also conducted. METHODS Phenotype was defined by pretreatment Phe levels. A standard prediction system based on arbitrary assigned values was employed to measure genotype-phenotype concordance. Patients were also estimated as BH4 -responders according to the responsiveness previously reported for their mutations and genotypes. RESULTS A 48.3% concordance rate between genotype-predicted and observed phenotypes was found. When the predicted phenotypes included those reported at the BIOPKU database, the concordance rate reached 77%. A total of 18 genotypes from 30 patients (29.4%) were estimated as of potential or probable BH4 responsiveness. Inconsistencies were observed in genotypic combinations including the common "moderate" mutations p.R261Q, p.V388M, and p.I65T and the mild mutations p.L48S, p.R68S, and p.L249F. CONCLUSION The high discordance rate between genotype-predicted and observed metabolic phenotypes in this study seems to be due partially to the high frequency of the so-called "moderate" common mutations, p.R261Q, p.V388M, and p.I65T, which are reported to be associated to erratic or more severe than expected metabolic phenotypes. Although our results of BH4 estimated responsiveness must be regarded as tentative, it should be emphasized that genotyping and genotype-phenotype association studies are important in selecting patients to be offered a BH4 overload test, especially in low-resource settings like Brazil.
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Affiliation(s)
- Eduardo Vieira Neto
- Agência Nacional de Saúde SuplementarGerência de Monitoramento AssistencialRio de JaneiroBrazil
- Serviço de Genética MédicaInstituto de Puericultura e Pediatria Martagão GesteiraUniversidade Federal do Rio de JaneiroRio de JaneiroBrazil
| | - Francisco Laranjeira
- Centro de Genética Médica Doutor Jacinto MagalhãesUnidade de Bioquímica GenéticaPortoPortugal
| | - Dulce Quelhas
- Centro de Genética Médica Doutor Jacinto MagalhãesUnidade de Bioquímica GenéticaPortoPortugal
- Unidade Multidisciplinar de Investigação BiomédicaUniversidade do PortoPortoPortugal
| | - Isaura Ribeiro
- Centro de Genética Médica Doutor Jacinto MagalhãesUnidade de Bioquímica GenéticaPortoPortugal
- Unidade Multidisciplinar de Investigação BiomédicaUniversidade do PortoPortoPortugal
| | - Alexandre Seabra
- Centro de Genética Médica Doutor Jacinto MagalhãesUnidade de Bioquímica GenéticaPortoPortugal
- Instituto de Ciências Biomédicas Abel SalazarUniversidade do PortoPortoPortugal
| | - Nicole Mineiro
- Centro de Genética Médica Doutor Jacinto MagalhãesUnidade de Bioquímica GenéticaPortoPortugal
| | - Lilian M. Carvalho
- Serviço de MetabologiaInstituto Estadual de Diabetes e Endocrinologia Luiz CapriglioneRio de JaneiroBrazil
| | - Lúcia Lacerda
- Centro de Genética Médica Doutor Jacinto MagalhãesUnidade de Bioquímica GenéticaPortoPortugal
| | - Márcia G. Ribeiro
- Serviço de Genética MédicaInstituto de Puericultura e Pediatria Martagão GesteiraUniversidade Federal do Rio de JaneiroRio de JaneiroBrazil
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9
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Ashe K, Kelso W, Farrand S, Panetta J, Fazio T, De Jong G, Walterfang M. Psychiatric and Cognitive Aspects of Phenylketonuria: The Limitations of Diet and Promise of New Treatments. Front Psychiatry 2019; 10:561. [PMID: 31551819 PMCID: PMC6748028 DOI: 10.3389/fpsyt.2019.00561] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Accepted: 07/17/2019] [Indexed: 12/30/2022] Open
Abstract
Phenylketonuria (PKU) is a recessive disorder of phenylalanine metabolism due to mutations in the gene for phenylalanine hydroxylase (PAH). Reduced PAH activity results in significant hyperphenylalaninemia, which leads to alterations in cerebral myelin and protein synthesis, as well as reduced levels of serotonin, dopamine, and noradrenaline in the brain. When untreated, brain development is grossly disrupted and significant intellectual impairment and behavioral disturbance occur. The advent of neonatal heel prick screening has allowed for diagnosis at birth, and the institution of a phenylalanine restricted diet. Dietary treatment, particularly when maintained across neurodevelopment and well into adulthood, has resulted in markedly improved outcomes at a cognitive and psychiatric level for individuals with PKU. However, few individuals can maintain full dietary control lifelong, and even with good control, an elevated risk remains of-in particular-mood, anxiety, and attentional disorders across the lifespan. Increasingly, dietary recommendations focus on maintaining continuous dietary treatment lifelong to optimize psychiatric and cognitive outcomes, although the effect of long-term protein restricted diets on brain function remains unknown. While psychiatric illness is very common in adult PKU populations, very little data exist to guide clinicians on optimal treatment. The advent of new treatments that do not require restrictive dietary management, such as the enzyme therapy Pegvaliase, holds the promise of allowing patients a relatively normal diet alongside optimized mental health and cognitive functioning.
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Affiliation(s)
- Killian Ashe
- Neuropsychiatry Unit, Royal Melbourne Hospital, Melbourne, VIC, Australia
| | - Wendy Kelso
- Neuropsychiatry Unit, Royal Melbourne Hospital, Melbourne, VIC, Australia
| | - Sarah Farrand
- Neuropsychiatry Unit, Royal Melbourne Hospital, Melbourne, VIC, Australia
| | - Julie Panetta
- Statewide Adult Metabolic Service, Royal Melbourne Hospital, Melbourne, VIC, Australia
| | - Tim Fazio
- Statewide Adult Metabolic Service, Royal Melbourne Hospital, Melbourne, VIC, Australia.,Melbourne Medical School, University of Melbourne, Melbourne, VIC, Australia
| | - Gerard De Jong
- Statewide Adult Metabolic Service, Royal Melbourne Hospital, Melbourne, VIC, Australia.,Melbourne Medical School, University of Melbourne, Melbourne, VIC, Australia
| | - Mark Walterfang
- Neuropsychiatry Unit, Royal Melbourne Hospital, Melbourne, VIC, Australia.,Melbourne Neuropsychiatry Centre, University of Melbourne and North-Western Mental Health, Melbourne, VIC, Australia.,Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, VIC, Australia
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Abstract
Inborn errors of metabolism comprise a wide array of diseases and complications in the pediatric patient. The rarity of these disorders limits the ability to conduct and review robust literature regarding the disease states, mechanisms of dysfunction, treatments, and outcomes. Often, treatment plans will be based on the pathophysiology associated with the disorder and theoretical agents that may be involved in the metabolic process. Medication therapies usually consist of natural or herbal products. Established efficacious pediatric doses for these products are difficult to find in tertiary resources, and adverse effects are routinely limited to single case reports. This review article attempts to summarize some of the more common inborn errors of metabolism in a manner that is applicable to pharmacists who will provide care for these patients.
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Pateras K, Nikolakopoulos S, Mavridis D, Roes KC. Interval estimation of the overall treatment effect in a meta-analysis of a few small studies with zero events. Contemp Clin Trials Commun 2018; 9:98-107. [PMID: 29696231 PMCID: PMC5898531 DOI: 10.1016/j.conctc.2017.11.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Revised: 10/11/2017] [Accepted: 11/29/2017] [Indexed: 12/13/2022] Open
Abstract
When a meta-analysis consists of a few small trials that report zero events, accounting for heterogeneity in the (interval) estimation of the overall effect is challenging. Typically, we predefine meta-analytical methods to be employed. In practice, data poses restrictions that lead to deviations from the pre-planned analysis, such as the presence of zero events in at least one study arm. We aim to explore heterogeneity estimators behaviour in estimating the overall effect across different levels of sparsity of events. We performed a simulation study that consists of two evaluations. We considered an overall comparison of estimators unconditional on the number of observed zero cells and an additional one by conditioning on the number of observed zero cells. Estimators that performed modestly robust when (interval) estimating the overall treatment effect across a range of heterogeneity assumptions were the Sidik-Jonkman, Hartung-Makambi and improved Paul-Mandel. The relative performance of estimators did not materially differ between making a predefined or data-driven choice. Our investigations confirmed that heterogeneity in such settings cannot be estimated reliably. Estimators whose performance depends strongly on the presence of heterogeneity should be avoided. The choice of estimator does not need to depend on whether or not zero cells are observed.
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Affiliation(s)
- Konstantinos Pateras
- Department of Biostatistics and Research Support, Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, 3508 GA Utrecht, The Netherlands
- Corresponding author. Department of Biostatistics and Research Support, Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Huispost Str.6.131, PO Box 85500, 3508 GA Utrecht, The Netherlands.
| | - Stavros Nikolakopoulos
- Department of Biostatistics and Research Support, Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, 3508 GA Utrecht, The Netherlands
| | - Dimitris Mavridis
- Department of Primary Education, School of Medicine, University of Ioannina, University Campus, 45110 Ioannina, Greece
- Department of Hygiene and Epidemiology, School of Medicine, University of Ioannina, University Campus, 45110 Ioannina, Greece
| | - Kit C.B. Roes
- Department of Biostatistics and Research Support, Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, 3508 GA Utrecht, The Netherlands
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