Evaluación del seguimiento de 29 niños chilenos con la enfermedad de la orina olor a jarabe de arce clásica

Abstract

Introduction: Maple Syrup Urine Disease (MSUD) is caused by a defect of the ketoacid dehydrogenase enzyme complex of the branched amino acids Valine, Isoleucine and Leucine (VIL). The treatment consists of a leucine-restricted diet. Objective: To evaluate the long-term follow-up in children with MSUD. Methodology: 29 records were reviewed of patients with MSUD, of which 24 were clinically identified (> 5th day of life), 4 cases by MSUD family history and one by neonatal screening (< 5th day of life). Leucine (Leu) levels were measured at diagnosis (Biotronic 2000) and during follow-up (mass spectrometry). The number of decompensation events, Total Intellectual Quotient (TIQ, Bayley and Wechsler scale) and nutritional status were also measured. STATA statistical software version 9.2 was applied (p≤0.05). Results: Mean age at diagnosis was 14 days old. In all cases the diagnosis was confirmed by elevated levels of Leu and alloisoleucin. When comparing the TIQ of 19 cases over 3 years old with their age at diagnosis, it was observed that those cases screened by the 5th day of life had a TIQ 84.6 ± 13, while those diagnosed later had a TIQ 73 ± 17 (p≤0.05). In assessing the number of hospitalizations that occurred during follow-up, we determined that the 5 cases screened early never had a metabolic crisis and had a higher TIQ than those who had had one or more decompensation (92 and 74, respectively, p≤0.05). An inverse correlation was observed between the Leu+Isoleucine value and TIQ. Conclusion: The diagnosis before the 5th day of life and a good metabolic control during follow-up, enables children with MSUD to have normal cognitive development.