Transient neonatal multiple acyl-CoA dehydrogenase deficiency due to riboflavin deficiency in an infant on total parenteral nutrition.

Riboflavin, a vital water-soluble vitamin, serves as a cofactor for numerous enzymes involved in cellular energy metabolism. Riboflavin deficiency can lead to diverse clinical manifestations and metabolic changes that mimic multiple acyl-CoA dehydrogenase deficiency (MADD). We report a case of a preterm female infant dependent on total parenteral nutrition (TPN) with insufficient riboflavin intake. The infant exhibited clinical and biochemical features resembling MADD; however, molecular analysis revealed no pathogenic or likely pathogenic variants associated with MADD or riboflavin transporter defects. Treatment with riboflavin, L-carnitine and multivitamin supplementation resulted in the resolution of clinical and biochemical abnormalities within 1 week. This case highlights that the transient MADD-like features were attributable to riboflavin deficiency induced by TPN.