A preterm infant with secondary carnitine deficiency due to MCT formula--effective treatment of L-carnitine.

We report a preterm infant who was prescribed an MCT formula and subsequently developed carnitine deficiency with liver dysfunction and an elevation of serum CK level. A male infant who had been born at 24 weeks' gestation with birth weight 799 g, was fed with an MCT formula containing 76.8% of all kinds of lipids, because of his steatorrhea after the 30th day. On the 100th day, he was noted hepatomegaly and elevation of serum levels of AST, ALT and CK. The needle biopsy of the liver indicated the existence of the liver damage. He showed low serum carnitine with high urinary loss of acylcarnitine and dicarboxylic aciduria. Administration of L-carnitine was an effective treatment. The carnitine deficiency might be exaggerated by an increased urinary loss of acylcarnitine. We should be cautious of the risk of carnitine deficiency in preterm infants during prolonged use of MCT formula.