Stiff-man syndrome: report of a case.

A 40-year-old Taiwanese farmer developed progressive stiffness and pain in the lower back with intermittent cramps over a 3-year period. The cramps were extremely painful and the patient was sensitive to any sudden movement or external stimulation. His lower back was so stiff that the patient had great difficulty performing daily activities and walked with a rigid and straight back. The stiffness of the muscles subsided during normal sleep. Except for a left S1 radiculopathy, no other neurologic abnormalities were noted. Electromyography showed spontaneous continuous muscle fiber activity which was markedly suppressed after a trial with 20 mg intravenous diazepam. The muscular stiffness disappeared during treatment with oral diazepam 80 mg daily, which was tapered to 15 mg daily without any recurrence of spasm for 20 months. This is the first report of stiff-man syndrome in a Taiwanese patient and emphasizes the importance of recognizing this treatable disease.