Maple syrup urine disease in Brazil: a panorama of the last two decades

To characterize a sample of Brazilian patients with maple syrup urine disease (MSUD) diagnosed between 1992 and 2011. In this retrospective study, patients were identified through a national reference laboratory for the diagnosis of MSUD and through contact with other medical genetics services across Brazil. Data were collected by means of a chart review. Eighty-three patients from 75 families were enrolled in the study (median age, 3 years; interquartile range [IQR], 0.57–7). Median age at onset of symptoms was 10 days (IQR 5–30), whereas median age at diagnosis was 60 days (IQR 29–240, p=0.001). Only three (3.6%) patients were diagnosed before the onset of clinical manifestations. A comparison between patients with (n=12) and without (n=71) an early diagnosis shows that early diagnosis is associated with the presence of positive family history and decreased prevalence of clinical manifestations at the time of diagnosis, but not with a better outcome. Overall, 98.8% of patients have some psychomotor or neurodevelopmental delay. In Brazil, patients with MSUD are usually diagnosed late and exhibit neurological involvement and poor survival even with early diagnosis. We suggest that specific public policies for diagnosis and treatment of MSUD should be developed and implemented in the country. Caracterizar uma amostra de pacientes brasileiros com a doença da urina de xarope de bordo (DXB) diagnosticados entre 1992 e 2011. Neste estudo retrospectivo, os pacientes foram identificados por meio de um laboratório de referência nacional para o diagnóstico de DXB e por meio do contato com outros serviços de genética médica no Brasil. Os dados foram coletados por meio de uma revisão de prontuários. 83 pacientes de 75 famílias foram incluídos no estudo (idade média: 3 anos; intervalo interquartil (IQR): 0,57-7). A idade média no surgimento dos sintomas era de 10 dias (IQR: 5-30), ao passo que a idade média no diagnóstico era de 60 dias (IQR: 29-240; p=0,001). Somente três (3,6%) pacientes foram diagnosticados antes do surgimento de manifestações clínicas. Uma comparação entre pacientes com (n=12) e sem (n=71) um diagnóstico precoce mostra que o diagnóstico precoce está associado à presença de histórico familiar positivo e à redução na prevalência de manifestações clínicas no momento do diagnóstico, porém sem melhor resultado. Em geral, 98,8% dos pacientes têm algum atraso no desenvolvimento psicomotor ou neurológico. No Brasil, os pacientes com DXB normalmente recebe