When one disease is not enough: succinyl-CoA: 3-oxoacid coenzyme A transferase (SCOT) deficiency due to a novel mutation in OXCT1 in an infant with known phenylketonuria

Abstract

AbstractA 9-month-old Turkish girl was admitted several times within 3 months to the hospital in reduced general condition and with extreme tachypnea. The patient had been diagnosed with phenylketonuria (PKU) in newborn screening and has been treated with a low phenylalanine diet and amino acid supplements. Each time an unexplained pronounced metabolic acidosis was noted, and the child was treated with sodium-bicarbonate and glucose-electrolyte infusions. The acidosis with only slightly abnormal glucose, normal lactate levels and pronounced ketonuria suggested a defect in ketone body utilization. Succinyl-CoA: 3-oxoacid CoA transferase (SCOT) enzyme activity was low in patient’s fibroblasts. Mutation analysis of the corresponding