Muscle pathology in Bassen-Kornzweig syndrome and vitamin E deficiency.

A constellation of histologic abnormalities was demonstrated in the quadriceps femoris muscle of a 29-year-old man with Bassen-Kornzweig syndrome. The abnormalities consisted of fibers containing dense lipid inclusions ceroid and lipofuscin, a spectrum of fiber size, architectural changes, and an increase in central nuclei. A dramatic shift of fiber type predominance, from type I to type II, was demonstrated in the myosin ATPase reactions one year after vitamin E therapy. Despite an apparent reduction in the number of fibers containing lipid and ceroid granules in the second biopsy, neuromyopathic changes worsened. The relationship of these findings to vitamin E therapy is discussed.