Eosinophilic fasciitis. Review and report of six cases.

Six patients with eosinophilic fasciitis are presented. This syndrome is characterized by indurative swellings of arms and legs, with rapidly progressing difficulties in extending elbows, wrists, and fingers, and often limited motion of shoulders and ankle joints. Pain when contracting muscles, and weakness of proximal muscles and hand grip are common features. The frequent occurrence of localized skin lesions has presented differential diagnostic difficulties to systemic sclerosis and to polymyositis. Visceral involvement and Raynaud's phenomena, however, are absent or mild. Blood eosinophilia, hypergammaglobulinemia, and unspecific signs of inflammation are found. Biopsy of muscle fascia gives characteristic histopathological findings of cell infiltrations (mostly mononuclear cells, frequently eosinophils) and vascular proliferation, in the middle layer of a thickened fascia. Skin changes are prevalent, but not conclusive for the diagnosis, and myositis in some patients might be difficult to distinguish from polymyositis. The importance of the clinical recognition of eosinophilic fasciitis and the inclusion of fascia in diagnostic muscle biopsies, is underlined.