The cytoplasmic bodies in a congenital myopathy can be stained with antibodies to desmin, the muscle-specific intermediate filament protein.

Cytoplasmic bodies found in a muscle biopsy from a 14-year-old girl afflicted with a lifelong congenital myopathy reveal an electron-dense core surrounded by 7-10 nm filaments. Typing of the kind of intermediate filaments present shows that they are of the desmin type.