Short‐chain<scp>L</scp>‐3‐hydroxyacyl‐CoA dehydrogenase deficiency in muscle: A new cause for recurrent myoglobinuria and encephalopathy

Abstract

We report on a 16-year-old girl with short-chain L-3-hydroxyacyl-coenzyme A (CoA) dehydrogenase deficiency resulting in juvenile-onset recurrent myoglobinuria, hypoketotic hypoglycemic encephalopathy, and hypertrophic/dilatative cardiomyopathy. Urinary organic acids showed traces of 3-hydroxy-dodecanedioic acids and small amounts of suberic, sebacic, and adipic acids. There was a marked decrease in L-3-hydroxyacyl-CoA dehydrogenase activity in muscle with acetoacetyl-CoA as substrate (2.48 mumol/min/gm; normal = 6.90 +/- 1.80 mumol/min/gm of tissue; n = 11), contrasting with normal L-3-hydroxyacyl-CoA dehydrogenase activity with 3-ketooctanoyl-CoA and 3-ketopalmitoyl-CoA as substrates. Short-chain L-3-hydroxyacyl-CoA dehydrogenase activity was normal in fibroblasts, suggesting a tissue-specific defect.