Polymyositis and the Spectrum of Scleroderma Disorders

Polymyositis (PM) is usually associated to other autoimmune or connective tissue diseases. The authors report the case of a 59-year-old man with pulmonary fibrosis, who presented with constitutional symptoms and gradually developed proximal muscle weakness, Raynaud phenomenon, and dysphagia. Besides creatine kinase (CK) elevation, he had positive anti-Polymyositis-Scleromyositis (PM-Scl) and anti-Sjögren's-syndrome A (SSA) antibodies. Nailfold capillaroscopy showed a scleroderma pattern and muscle biopsy revealed necrosis, regeneration of muscle fibers, and inflammatory infiltrate. Prednisolone was started, with great improvement. Taking into account the overlap features between PM and systemic sclerosis sine scleroderma, it is important to closely monitor the patient for signs of pulmonary and cardiac decompensation.