Two patients with distal muscular dystrophy and autonomic nerve dysfunction.
Two female patients with distal muscular dystrophy (Miyoshi) are reported. Neurological examination revealed marked weakness and a low skin temperature of both lower legs, especially over the gastrocnemius muscle. Biopsy specimens of the anterior tibial muscle exhibited myopathological features compatible with a dystrophic change and showed positive dystrophin reactions with all six antibodies used. Autonomic nerve studies in both patients, including laser Doppler flowmetry (LDF), component analysis of the cardiographic R-R interval and a sympathetic skin response (SSR) test, demonstrated marked abnormalities, such as sensitive vasoconstrictive responses, a suppressed peak of low frequency components and an absence of SSR, respectively, compared with findings in healthy controls. Sympathetic nerve blocking by means of epidural anesthesia produced clinical improvement and a marked decrease in the serum CK level in one patient. Although the etiology of autonomic nerve disturbances in these cases remains to be elucidated, a positive immunoreactivity of nerve growth factor receptor (NGFR) implies the possibility of some unknown sympathetic neurovascular disorder involving muscle degeneration.