Malignant hyperthermia in a family. The ultrastructure of muscle biopsies of healthy members.

Twelve healthy relatives of two children who died of malignant hyperthermia--volunteered to give biopsies of striated muscle. Electron microscopy of their muscles revealed nonspecific myofibrillary degeneration and profound alterations of parts of muscle fibres. Furthermore, constructional faults were found in the architecture of the muscle. Previous investigations correlated with these abnormalities support the assumption, that inborn errors of metabolism may involve membranes of other tissues as well as striated muscle.