Controlled Trial of Plasma Exchange and Leukapheresis in Polymyositis and Dermatomyositis

Abstract
The therapeutic options for patients with polymyositis or dermatomyositis that is resistant to corticosteroids are limited, unproved, and often toxic. Uncontrolled trials concluded that both plasma exchange and leukapheresis are beneficial, but despite the considerable use of these approaches, proof of their efficacy is lacking.