Nemaline rod disease, with reference to the routine use of histochemical methods in autopsy investigations.

A 50-year-old man had suffered from an undiagnosed form of muscle disease for most of his life. Death was due to cardiac failure. Numerous samples of muscle, obtained at autopsy, were subjected to the usual histochemical techniques used in investigating neuromuscular disease. Frozen sections revealed the abnormal accumulations of Z-band protein that characterize nemaline rod disease. That this disorder would have escaped diagnosis had only routine paraffin-embedded sections been examined is emphasized.