RESUMO
Isovaleric acidemia is an autosomal recessive disease of leucine metabolism. The clinical presentation is variable and three phenotypes are described, asymptomatic, acute neonatal, and chronic intermittent. Infections are the most important trigger for catabolic crises. Diagnosis is based on the detection of isovalerylglycine CoA in urine and elevated levels of isovaleryl (C5) carnitine in blood. Long-term treatment consists of prevention of catabolic state, dietary restriction, and supplementation with L-carnitine and/or L-glycine. We present the case of a three-year-old female patient with multiple episodes of decompensation since the age of two years. The episode in which she was diagnosed had encephalopathy, with no neurological sequelae. Currently, the patient continues with dietary restrictions and supplementation with good nutritional and growth results for her age.