[Clinical and myopathological findings in polymyositis]

The present report analyzed a clinical and myopathological findings of 60 patients defined for the diagnosis of polymyositis. Patients were classified in four groups according to the system Walton and Adams. Forty five per cent were classified as Group I, 28.3 per cent as Group II, 15.0 per cent as Group III and 11.7 per cent as Group IV. Seven patients were associated with a malignant neoplasm and all of them were over fifty. The primary growth was carcinoma of the lung in 2, of the prostate, ovarium, stomach in one case each, and in one case a chronic myelogenous leukemia and in one case a malignant lymphoma. The female to male ratio was 2:1. Though cases were seen in all age groups, the largest number was in the sixth decade. The presenting symptoms and signs were essentially similar to those reported before. Proximal lower and upper limb weakness was the most frequent symptoms (91.7 and 83.3 per cent respectively). Other characteristic symptoms were skin changes, muscle pain, arthralgia and Raynaud's phenomenon. The CK was measured at the time of presentation in 58 of the 60 cases. Normal values were found in 18.3 per cent of cases. In general, muscle biopsy was performed in the first stage of the disease. A diagnostically abnormal biopsy was 55 cases (92 per cent), but 8 per cent of cases had normal biopsy. The characteristic changes in the biopsies from 60 cases were muscle fiber necrosis, inflammatory infiltration, fibrosis, basophilia and increase of internal nuclei. We could not get a significant difference between the two groups. However all of the cases of Group IV had muscle fiber necrosis, inflammatory infiltration and fibrosis.