Histochemical, ultrastructural, and biochemical studies were performed on two muscle biopsy specimens from a 40-yearold man with progressive ophthalmoplegia, facial and proximal limb weakness. In the first biopsy specimen there was increased glycogen and large numbers of mitochondria with paracrystalline inclusions. Glycogen content was 2.2% but glycolysis and glycogen enzyme values were normal. In the second biopsy specimen, mitochondrial alterations were less marked and glycogen content was normal. Mitochondria isolated from this biopsy sample showed lack of respiratory control with α-glycerophosphate as a substrate. These data suggest a primary mitochondrial abnormality; the variability of glycogen content may be related to the degree of mitochondrial involvement.
DiMauro S, Schotland DL, Bonilla E, Lee C, Gambetti P, Rowland LP. Progressive Ophthalmoplegia, Glycogen Storage, and Abnormal Mitochondria. Arch Neurol. 1973;29(3):170–179. doi:10.1001/archneur.1973.00490270052008
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