Abstract: Dermatomyositis (DM) is an inflammatory connective tissue disease of unknown cause. To investigate its clinical manifestation, treatment response and the relationship to internal malignancies, 86 patients with DM were retrospectively analyzed. DM was seen predominantly in women with a ratio of male to female 1:3.1. The age of onset of 75% of the patients was between 20 to 60.51.2% of the patients with skin lesions manifested as first presentation and 44.2% with simultaneous skin and muscte diseases. The mostly seen skin manifestations were heliotrope eruption (84.9%), Gottron's papule (59.3%), poikiloderma (61.6%) and periungual erythema (41.9%). Muscles of upper and lower proximal extremities were mostly involved (80.2% and 79.1% respectively), followed by that of esophagus (31.4%). Increased serum levels of AST (61.0%), CPK (50.7%) and LDH (59.2%) were the main laboratory abnormalities. 70.8% of the patients were found to have increased 24 h creatine excretion. 86.5% patients showed abnormal EMG. Internal malignancies were found in 6 patients. 5 patients had interstitial pneumonia. Most patients responded well to corticosteroid, and in some cases, the combination of corticosteroid and methotrexate. 4 patients died of malignancies, 3 side-effect of the corticosteroid and 1 unrelated disease.

Key words: Dermatomyositis, Malignancies