A critical reappraisal of dietary practices in methylmalonic acidemia raises concerns about the safety of medical foods. Part 1: isolated methylmalonic acidemias.
Genet Med
; 18(4): 386-95, 2016 Apr.
Article
en En
| MEDLINE
| ID: mdl-26270765
ABSTRACT
PURPOSE:
Medical foods for methylmalonic acidemias (MMAs) and propionic acidemias contain minimal valine, isoleucine, methionine, and threonine but have been formulated with increased leucine. We aimed to assess the effects of imbalanced branched-chain amino acid intake on metabolic and growth parameters in a cohort of patients with MMA ascertained via a natural history study.METHODS:
Cross-sectional anthropometric and body-composition measurements were correlated with diet content and disease-related biomarkers in 61 patients with isolated MMA (46 mut, 9 cblA, and 6 cblB).RESULTS:
Patients with MMA tolerated close to the recommended daily allowance (RDA) of complete protein (mut(0) 99.45 ± 32.05% RDA). However, 85% received medical foods, in which the protein equivalent often exceeded complete protein intake (35%). Medical food consumption resulted in low plasma valine and isoleucine concentrations, prompting paradoxical supplementation with these propiogenic amino acids. Weight- and height-for-age z-scores correlated negatively with the leucine-to-valine intake ratio (r = -0.453; P = 0.014; R(2) = 0.209 and r = -0.341; P = 0.05; R(2) = 0.123, respectively).CONCLUSION:
Increased leucine intake in patients with MMA resulted in iatrogenic amino acid deficiencies and was associated with adverse growth outcomes. Medical foods for propionate oxidation disorders need to be redesigned and studied prospectively to ensure efficacy and safety.Genet Med 18 4, 386-395.
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Dieta
/
Errores Innatos del Metabolismo de los Aminoácidos
Tipo de estudio:
Clinical_trials
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Diagnostic_studies
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Observational_studies
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Prevalence_studies
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Risk_factors_studies
Límite:
Adolescent
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Adult
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Child
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Child, preschool
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Female
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Humans
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Male
Idioma:
En
Revista:
Genet Med
Asunto de la revista:
GENETICA MEDICA
Año:
2016
Tipo del documento:
Article
País de afiliación:
Estados Unidos