INITIAL CLINICAL PRESENTATION IN CASES OF INBORN ERRORS OF METABOLISM IN A REFERENCE CHILDREN'S HOSPITAL: STILL A DIAGNOSTIC CHALLENGE.

OBJECTIVE: To assess the initial clinical presentation of confirmed cases of inborn errors of metabolism (IEM) at a reference facility for pediatric care.

METHODS: Cross-sectional, observational and descriptive study with data collection of outpatients, from January 2009 to December 2013. Inclusion criterion: referral to IEM investigation. Exclusion criterion: prior diagnosis of IEM. Analyzed variables: identification data; status of diagnostic investigation; family history of IEM; initial clinical presentation, laboratory abnormalities related to the hypothesis of IEM. Descriptive statistical methods were used in the data analysis.

RESULTS: We included 144 patients in the study, of which 62.5% were male. The mean and median ages were, respectively, 4.3 ± 4.7 years and 2.6 years. Twelve patients (8.3%) had a confirmed diagnosis of IEM (three with aminoacidopathies, three with organic acidemias, two with urea cycle disorders and four with lysosomal storage diseases). Cognitive impairment and seizures were the initial signs and symptoms, followed by growth retardation, neuropsychomotor developmental delay, seizures and hepatomegaly. The main laboratory abnormalities in the diagnosis were hyperammonemia and metabolic acidosis.

CONCLUSIONS: The diagnosis of IEM still creates challenges to the pediatric practice. In this study, we identified the following factors: difficulty to access specific laboratory tests, reduced number of experts and poor dissemination of knowledge among healthcare schools. The early diagnosis of IEM majorly impacts the treatment and prevention of sequelae and should be considered in the initial diagnostic hypotheses.