2-methyl-3-hydroxybutyryl-CoA dehydrogenase deficiency: Case report

We describe a patient with 2-methyl-3-hydroxybutyryl-CoA dehydrogenase deficiency (MHBD), which is a rare metabolic disorder resulted from an inborn error of isoleucine metabolism. A 7-month-old male infant with previously normal developmental milestones started with symptoms of fever, torpor and persistent metabolic acidosis during the course of a respiratory infection. The condition progressed to an acute deterioration and cardiac arrest. After cardiorespiratory resuscitation, he was admitted at the Intensive Care Unit. He presented with seizure, coma, metabolic acidosis and disturbs of hydroelectrolytic and glycemic imbalance. A head CT scan showed hypodensity in basal ganglia, thalamus, dentate nuclei and mesencephalon. The diagnosis was established through dosage of organics acids in the urine that showed increased excretion of 2-methyl-3-hydroxybutyric acid. Laboratory tests, neuroimage aspects, history of parents consanguinity, report of death of other probands and clinical evolution of the patient led to the suspicion of an inborn error of metabolism