The fasciitis-panniculitis syndromes. Clinical and pathologic features.

The authors propose to encompass under the designation of "fasciitis-panniculitis syndromes" (FPS) a group of disorders characterized by induration of the skin due to chronic inflammation and fibrosis of the subcutaneous septa and muscular fascia. The prototype of the FPS is eosinophilic fasciitis. Thirty-two consecutive patients with FPS were cared for at the author's hospital during a 10-year period. The association of the FPS with other diseases, clinical presentations, histologic features, and response to treatment were analyzed. Idiopathic FPS, that is, eosinophilic fasciitis, was diagnosed in 14 patients. In the remaining 18 cases, the FPS were ascribed to vascular disorders (n = 6), infections (n = 6), and neoplastic disorders (n = 3), while trauma, insect bites, and Sweet syndrome antedated the FPS in 1 patient each. The lesions had a sleeve-like distribution in 20 patients, plaque-like distribution in 7, and a combined pattern in 5. Skin biopsies revealed lesions in the deep subcutaneous layers with the pathologic triad of septal and fascial fibrosis, chronic inflammatory infiltration, and small-vessel vasculopathy. Spontaneous improvement occurred in 4 cases. Following cimetidine monotherapy, complete remission was achieved in an additional 3 of 5 patients. The concept of the FPS serves to advance our understanding on several fronts: emphasizing the clinical and etiologic diversity; recognizing a stereotypic tissue reaction pattern; highlighting the panniculitis in addition to the fasciitic component; and describing a similar response to drug therapy in different clinical settings. Based on the results of the present series, cimetidine may be recommended as first-line treatment.