Non-Neoplastic Dermatopathology

5.6

E OSINOPHILIC FASCIITIS VS SCLERODERMA

Eosinophilic Fasciitis

Scleroderma

Age

Adults, typically in fourth and fifth decades of life.

All ages, but most commonly between 30 and 50 years of age. There is a female predominance. Fingers, hands, and face followed by distal extremities. Trunk and proximal extremities are typically spared. Disease of unknown cause involving immune dysregulation, microangiopathy, and excess synthesis of extracellular matrix with deposition of increased amounts of collagen in the skin. Slowly progressive thickening and hardening of the skin. Skin edema and erythema is followed by induration and mottled pigmentation. Often associated with abnormal nailfold capillaries and Raynaud phenomenon. Late-stage lesions may have calcinosis and ulceration. 1. Biopsy appears “squared off” at low magnification (Fig. 5.6.5) . 2. Dermis is expanded by sclerotic collagen bundles that appear swollen and smudgy with loss of intervening fenestrations (Fig. 5.6.6) . Sclerosis extends into subcutis but not into fascia. 3. Sclerotic collagen bundles obliterate fat surrounding adnexal structures (Fig. 5.6.7) . Adnexae are atrophic or absent in late stage lesions. 4. Patchy perivascular and interstitial infiltrate of lymphocytes and plasma cells (Fig. 5.6.8) . Eosinophils generally not prominent. Serology for systemic sclerosis-related autoantibodies including antinuclear antibody, anti-centromere, anti topoisomerase I (anti-Scl-70), and anti-RNA polymerase III. No peripheral eosinophilia.

Location

Extremities are symmetrically involved with exclusion of hands and feet. Trunk and neck involvement may be seen in widespread disease. Unknown. Trauma and strenuous exercise have been postulated as etiologic factors. Acute or subacute onset of erythema and pitting edema. Deep sclerosis creates diffuse induration and “peau d’orange” appearance as well as “groove sign” (collapse of superficial veins with elevation of extremity). Cutaneous symptoms may be accompanied by myalgias, weakness, and weight loss. No Raynaud phenomenon. Superficial findings in deep dermis and superficial subcutis of sclerosis and lymphoplasmacytic infiltrate may mimic morphea/scleroderma (Figs. 5.6.1 and 5.6.2) . 2. Fibrosis and thickening of the subcutis and fascia with an infiltrate of eosinophils, plasma cells, and histiocytes (Figs. 5.6.3 and 5.6.4) . Sclerosis extends into dermis only in extensive, severe cases. 3. Eosinophils may be transient and even absent in late stages of the disease or if systemic corticosteroids have been administered. Testing for increased absolute eosinophil count and elevated inflammatory markers (erythrocyte sedimentation rate and C-reactive protein) may be useful in initial diagnosis and for detection of disease reactivation. 1. Full-thickness biopsy, including fascia, is necessary for diagnosis.

Etiology

Presentation

Histology

Special studies

(continued) Copyright © Wolters Kluwer, Inc. Unauthorized reproduction of the content is prohibited. 2023

259