Carnitine deficiency: clinical, morphological, and biochemical observations in a fatal case

A fatal case of carnitine deficiency is described, the 8th case reported. The patients had intermittent metabolic acidosis, fluctuating hepatomegaly, and progressive muscle weakness since 22 mth of age. One of 2 liver biopsies revealed lipid accumulation in the hepatocytes, and a muscle biopsy at age 5 years showed a lipid storage myopathy. Type 1 fibers were the most severely affected. Satellite and vascular endothelial cells also contained abnormal lipid deposits. Quantitative electron microscopy demonstrated an approximately 50-fold increase in lipid material, and a twofold increase in mitochondria in myofibres. The muscle carnitine level was less than one-seventh of the lowest value encountered in 74 biopsies from non-weak or neuromuscular disease controls. The basic abnormality in this patient is assumed to be a defect in carnitine biosynthesis.