RESUMO
Mitochondrial diseases are classified into the three major categories, defects of fatty acid oxidation, defects of pyruvate metabolism, and defects of the respiratory chain, and all of these cause severe neurologic dysfunction in the newborn period. Defects of the mitochondrial respiratory chain present as recurrent apnea, seizures, congenital lactic acidosis, hypotonia, hepatic dysfunction and hypertrophic cardiomyopathy in the neonatal period. Laboratory findings of hyperlactataemia(>2.5mM), elevated lactate/pyruvate(L/P) ratio(>20) and ketone body ratio(>2) suggest the diagnosis of mitochondrial respiratory chain defects. We report a case of mitochondrial respiratory chain defect diagnosed in the neonatal period presenting with multiorgan failure consisting of severe metabolic acidosis, comatous mental state, respiratory distress, hepatic dysfunction, renal failure with lactic acidosis(24mM), increased L/P ratois (55.6) and ketonuria (increased ratio of 3-hydroxybutyrate/acetoacetate).
