Evaluation of patients with inflammatory myopathies

Inflammatory Myopathies are a group of acquired diseases in which most important finding is subacute progressing symmetrical proximal muscle weakness and fatigue with mononuclear cells infiltration in the muscle tissue along with degeneration and regeneration of muscle fibers and elevation of the muscle enzymes. In nonspecific myositis, the important point is the prominent infiltration of the macrophages rather than lymphocytes in the muscle tissue, and intact fibers with infiltration are less common. In this retrospective and descriptive study, files and pathological slides of patients with myositis, hospitalized in the neurologic ward of Ghaem hospital or outpatients visited the neuropathology center from 1996 to 2006, were again evaluated. This study was approved by the local ethics. Overall, 39 patients with inflammatory myopathy diagnosis admitted during this period, of which were 56.4% males and 43.6% females. The average age of the women and men was 31 and 35.5 years respectively. Dysphagia was seen in 33.3%, tenderness and muscle pain in 41%, Reynoud's phenomen in 7.6%, elevated muscle enzymes in 82%, lung involvement in 5.1%, heart involvement in 5.1%, positive ANA in 5.1% and elevated ESR in 53.8% of the patients. Thirty-nine patients were evaluated in the neuropathology ward and amoung this group 36 cases had nonspecific myositis and 3 patients had polymyositis. In this study it is shown that polymyositis is a rare disease, and the presence of inflammation in muscle biopsy, elevated muscle enzymes and weakness of girdle muscles are not necessary for the polymyositis diagnosis confirmation. However, most of these cases are nonspecific myositis which will not respond to corticosteroid therapy

Serum muscle enzymes, muscle pathology and clinical muscle weakness: correlation in Thai patients with polymyositis/dermatomyositis.

The clinical correlation between serum muscle enzymes, muscle pathology and muscle weakness was studied in 100 Thai patients (22 males and 78 females) with polymyositis (PM) and dermatomyositis (DM). Their mean +/- SD age and duration of disease were 45.0 +/- 13.9 years and 6.3 + 13.4 months, respectively. There was idiopathic PM in 37 cases, idiopathic DM in 13, PM/DM associated with malignancy in 5 and PM associated with connective tissue disease in 45. Serum muscle enzymes including creatine phosphokinase, lactate dehydrogenase and aspartate aminotransferase were elevated in 87 per cent, 92 per cent, and 82 per cent of cases, respectively. Abnormal electromyographic findings that were compatible with inflammatory myopathy were found in 76 per cent of cases. Seventy-seven per cent had an abnormal muscle biopsy that was consistent with polymyositis. There was a significant correlation between serum muscle enzymes and muscle pathology (p < 0.01). The degree of muscle weakness correlated better with the degree of muscle destruction (p = 0.01) than the degree of muscle inflammation (p = 0.03). The erythrocyte sedimentation rate showed no correlation with serum muscle enzymes, muscle pathology or muscle weakness.