Body composition in patients with classical homocystinuria: body mass relates to homocysteine and choline metabolism

Introduction: Classical homocystinuria is a rare genetic disease caused by cystathionine beta-synthase deficiency, resulting in homocysteine accumulation. Growing evidence suggests that reduced fat mass in patients with classical homocystinuria may be associated with alterations in choline and homocysteine pathways. This study aimed to evaluate the body composition of patients with classical homocystinuria, identifying changes in body fat percentage and correlating findings with biochemical markers of homocysteine and choline pathways, lipoprotein levels and bone mineral density (BMD) T-scores.Methods: Nine patients with classical homocystinuria were included in the study. Levels of homocysteine, methionine, cysteine, choline, betaine, dimethylglycine and ethanolamine were determined. Body composition was assessed by bioelectrical impedance analysis (BIA) in patients and in 18 controls. Data on the last BMD measurement and lipoprotein profile were obtained from medical records.Results: of 9 patients, 4 (44%) had a low body fat percentage, but no statistically significant differences were found between patients and controls. Homocysteine and methionine levels were negatively correlated with body mass index (BMI), while cysteine showed a positive correlation with BMI (p < 0.05). There was a trend between total choline levels and body fat percentage (r = 0.439, p = 0.07). HDL cholesterol correlated with choline and ethanolamine levels (r = 0.757, p = 0.049; r = 0.847, p = 0.016, respectively), and total cholesterol also correlated with choline levels (r = 0.775, p = 0.041). There was no association between BMD T-scores and body composition.Conclusions: These results suggest that reduced fat mass is common in patients with classical homocystinuria, and that alterations in homocysteine and choline pathways affect body mass and lipid metabolism. (C) 2014 Elsevier B.V. All rights reserved.Research Incentive Fund (Fundo de Incentivo a Pesquisa, FIPE) of HCPAPRONEM/FAPERGSConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Univ Fed Rio Grande do Sul, Postgrad Program Genet & Mol Biol, Porto Alegre, RS, BrazilHosp Clin Porto Alegre, BRAIN Lab Basic Res & Adv Invest Neurosci, BR-90035003 Porto Alegre, RS, BrazilHosp Clin Porto Alegre, Med Genet Serv, BR-90035003 Porto Alegre, RS, BrazilUniversidade Federal de São Paulo, Reference Ctr Inborn Errors Metab, São Paulo, BrazilUniv Fed Rio Grande do Sul, Dept Physiol, Hosp Clin Porto Alegre, Gynecol Endocrinol Unit,Div Endocrinol, Porto Alegre, RS, BrazilUniv Fed Rio Grande do Sul, Food & Nutr Res Ctr, Hosp Clin Porto Alegre, Porto Alegre, RS, BrazilRobert Debre Hosp, AP HP, Biochem Hormonol Lab, Paris, FranceUniv Med Ctr Freiburg, Dept Gen Pediat, Lab Clin Biochem & Metab, Freiburg, GermanyUniversidade Federal de São Paulo, Reference Ctr Inborn Errors Metab, São Paulo, BrazilResearch Incentive Fund (Fundo de Incentivo a Pesquisa, FIPE) of HCPA: 11-0386PRONEM/FAPERGS: 11/2043-0CNPq: 308816/2013-7CNPq: 301742/2010-3CAPES: 12785-11Web of Scienc

Bone mineral density in patients with hepatic glycogen storage diseases

The association between bone mineral density (BMD) and hepatic glycogen storage diseases (GSDs) is still unclear. To evaluate the BMD of patients with GSD I, IIIa and IXα, a cross-sectional study was performed, including 23 patients (GSD Ia = 13, Ib = 5, IIIa = 2 and IXα = 3; median age = 11.9 years; IQ = 10.9–20.1) who underwent a dual-energy X-ray absorptiometry (DXA). Osteocalcin (OC, n = 18), procollagen type 1 N-terminal propeptide (P1NP, n = 19), collagen type 1 C-terminal telopeptide (CTX, n = 18) and 25-OH Vitamin D (n = 23) were also measured. The participants completed a 3-day food diary (n = 20). Low BMD was defined as a Z-score ≤ −2.0. All participants were receiving uncooked cornstarch (median dosage = 6.3 g/kg/day) at inclusion, and 11 (47.8%) presented good metabolic control. Three (13%) patients (GSD Ia = 1, with poor metabolic control; IIIa = 2, both with high CPK levels) had a BMD ≤ −2.0. CTX, OC and P1NP correlated negatively with body weight and age. 25-OH Vitamin D concentration was decreased in seven (30.4%) patients. Our data suggest that patients with hepatic GSDs may have low BMD, especially in the presence of muscular involvement and poor metabolic control. Systematic nutritional monitoring of these patients is essential

Brazilian Food Reference Guide for Phenylalanine Content: A Study Based on the Perception of PKU Patients and Health Providers

Abstract The mainstay of management of phenylketonuria (PKU) is restriction of dietary phenylalanine (Phe) intake. The present study sought to assess the perception and understanding of health care providers and lay users (patients/family members/caregivers) regarding the national reference database for checking the Phe content of foods, provided by the Brazilian Health Regulatory Agency (Anvisa), whose data are presented in the Table of Phenylalanine Content of Foods (TCFA-Anvisa) and recently in the Phenylalanine Content of Foods Dashboard (PCCFA-Anvisa); and to identify factors which interfere with the usability of these resources. Two online questionnaires, one for providers (n=33) and another for lay users (n=194), were used to collect sociodemographic information, knowledge about dietary management of PKU, sources of information about the Phe content of foods, and perception and understanding of the Anvisa tools. TCFA-Anvisa and PCCFA-Anvisa were not used as main sources of information by either group. Among the participants who had used these tools (15 providers;35 lay users), most considered the PCCFA-Anvisa to be superior or partially superior to the TCFA-Anvisa. The main limitations reported were related to layout and limited variety of foods. We suggest that the limitations identified in this study be considered for future improvement of these resources