A Challenging Case of Eosinophilic Fasciitis Without Classic Histopathological Findings.

Eosinophilic fasciitis (EF) is a rare dermatologic disease with clinical similarities to localized scleroderma and systemic sclerosis (SSc). Diagnosing EF is challenging due to overlapping clinical features among these conditions. Differentiating EF from localized scleroderma and SSc can be aided by laboratory tests, histopathological examination, and imaging studies. The diagnosis of EF specifically requires the exclusion of SSc and typically requires magnetic resonance imaging or en bloc fascial biopsy of affected areas. Here, the authors present a 75-year-old woman with a painful, violaceous rash on the legs and abdomen, leg swelling, and tightness around her upper abdomen. Review of systems revealed decreased appetite, unintentional weight loss, and shortness of breath on exertion. Physical examination showed a faint violaceous rash on the abdomen and legs as well as abdominal distention. The patient's clinical picture was complicated by worsening of the rash, development of chronic cough, continued unintentional weight loss, decreased appetite, early satiety, dry eyes, and dry mouth. An autoimmune process was considered, and the patient was seen by rheumatology, where an appropriate workup excluded localized scleroderma and SSc. EF was suspected and supported by magnetic resonance imaging findings showing fascial edema. En bloc fascial biopsy of the right thigh did not reveal classic EF findings.