DILATED CARDIOMYOPATHY DUE TO TYPE-II X-LINKED 3-METHYLGLUTACONIC ACIDURIA - SUCCESSFUL TREATMENT WITH PANTOTHENIC-ACID

A case of dilated cardiomyopathy in a young boy secondary to type II 3 -methyl-glutaconic aciduria is described. A metabolic cause for his di lated cardiomyopathy was suspected because of the development on the e lectrocardiogram of an unusual ''camel's hump'' shape of the T waves, and of progressive thickening with increasing echogenicity of the left ventricular wall. He initially improved on digoxin treatment, but did not maintain the response with conventional dietary treatment for thi s condition. Supplementation with L-carnitine was associated with rapi d deterioration in cardiac state, and may be contraindicated in this c ondition. At a point when the patient was moribund, large doses of pan tothenic acid, a precursor of coenzyme A, produced a dramatic and sust ained improvement in myocardial function and in growth, neutrophil cel l count, hypocholesterolaemia, and hyperuricaemia, which suggests that limitation of availability of coenzyme A is a fundamental pathologica l process in this condition. The clinical improvement has been maintai ned for 13 months, and myocardial function is now nearly normal. Oral pantothenol, unlike pantothenic acid, is not efficacious.