A histochemical and electron microscopic study of skeletal muscle in an adult case of Chédiak-Higashi syndrome.

To clarify the muscle pathology findings of a 39-year-old female Chédiak-Higashi syndrome (CHS) case with diffuse limb muscle atrophy, histochemical and electron microscopic studies were performed. In addition to neurogenic muscle atrophy due to the peripheral neuropathy, the most striking change seen by light microscopy was the widespread appearance of acid phosphatase-positive granules in many normal-looking muscle fibers. Coincident with the histochemical findings, electron microscopy showed many autophagic vacuoles containing glycogen particles and membranous structures in almost all muscle fibers. Although further studies are necessary, diffuse distribution of acid phosphatase-positive granules (autophagic vacuoles) in the skeletal muscle may reflect one of the generalized lysosomal abnormalities in CHS.