Two brothers affected with Becker’s muscular dystrophy in whom the disease followed completely different courses are reported from the Departments of Neurology/Neurosurgery and Genetics, Washington University Medical School, St. Louis, MO. The oldest sibling died at 37 following many years of severe disability whereas the younger sibling, now 26, has normal muscle strength. Symptoms began between 10 and 12 years of age in both patients. Analysis of the DNA from each revealed a similar deletion at the 5’ end of the dystrophin gene. The younger brother had epilepsy from age 13 and had been treated with phenytoin continuously for 13 years. 
COMMENT. The long term treatment with phenytoin from the onset of the muscle symptoms may have influenced the clinical course of the younger brother. The authors suggest that the action of a membrane stabilizer such as phenytoin may prevent the degeneration of the muscle fibers lacking dystrophin.