Methylmalonic aciduria (MMA) is an autosomal recessive in-born error of metabolism with a variation in the severity of the clinical manifestations, ranging from asymptomatic patients to fulminating neonatal forms causing severe ketosis, acidosis, hyperammonemia, pancytopenia, coma, and death. Severe cases can be treated with high doses of vitamin B12 and a diet low in proteins.
We describe an exceptional manifestation of MMA. A 14-month-old boy with a neonatal manifestation of MMA was admitted during an intercurrent infection with ketoacidosis and hypoglycemia.