Sarcoidosis appearing initially as polymyositis.

Polymyositis is an idiopathic progressive muscle disease. Occasionally, sarcoidosis can be associated with a polymyositis-like picture, both clinically and on laboratory investigation. However, serial sections of muscle biopsies will usually demonstrate sarcoid granulomas. A case of sarcoidosis that began as polymyositis with diffuse interstitial pneumonitis is presented.