Abstract: Purpose: Polymyositis (PM) is an inflammatory muscle disease, which has more overlap with scleroderma than other connective tissue diseases. The aim of this study is to compare the clinical, paraclinical and therapeutic response of polymyositis with polymyositis-scleroderma overlap syndrome. Methods: During the past 10 years we had 16 overlap syndromes and 40 primary polymyositis. All patients were classified by the American college of Rheumatology classification criteria. Ninety-seven items were checked in ...