[A case of polymyositis associated with primary biliary cirrhosis]

We studied a 67-year-old female suffered from polymyositis associated with primary biliary cirrhosis. She was pointed out liver dysfunction by screening test. Alkaline phosphatase, transaminase, and IgM were increased. Antimitochondrial antibody and antinuclear antibody were positive. Liver biopsy showed cell infiltrations in Glisson's capsules and destruction of cholangioles, being diagnosed as primary biliary cirrhosis (Scheuer Stage I). Four years later she showed a muscle weakness of four extremities and admitted to our department. Neurological examination revealed a severe weakness and atrophy of both proximal and distal muscles. Deep tendon reflex was decreased on four extremities. Laboratory examination showed a creatine kinase level of 312 IU/L, alkaline phosphatase 238 IU/L, gamma-glutamyl-transpeptidase 140 IU/L, Igm 416 mg/dl, antimitochondrial antibody titer 1:320, and antinuclear antibody titer 1:320. Muscle biopsy findings were compatible with polymyositis. Electron microscopic examination disclosed diffuse increase of mitochondria in subsarcolemma and intermyofibrils. Until now eight cases with polymyositis associated with primary biliary cirrhosis have been reported, but electron microscopic examination of muscle has not been carried out. It is necessary to examine mitochondria of muscle and liver in patients with polymyositis associated with primary biliary cirrhosis for the elucidation of its etiology.