Background/Purpose: Scleroderma is a chronic disease of unknown etiology characterized by skin fibrosis and is divided into two clinical entities: localized scleroderma and systemic sclerosis. Localized scleroderma differs from systemic sclerosis in that it is not accompanied by Raynaud’s phenomenon, acrosclerosis, and internal organ involvement. Early lesions of localized scleroderma are histologically characterized by lymphocytic perivascular infiltration in the reticular dermis and swollen endothelial cells. However, there have been few information regarding histological features other than these findings in localized scleorderma. Since en coup de sabre (ECDS) is a certain subset of localized scleroderma with a relatively uniform clinical image, we focused on this disease subset and evaluated its histopathological features.

Methods: We retrospectively evaluated 16 patients with ECDS on the basis of clinical and histological findings. For each patient, age, disease duration, and clinicopathologic data were obtained. Skin biopsies were evaluated for the following features: epidermal atrophy, spongiosis, vacuolar degeneration of the basal cell layer, necrotic keratinocytes, thickening of dermal collagen bundles, perivascular or periappendiceal inflammatory infiltrate, vacuolar changes of follicular epithelium, and melanin incontinence.

Results: Regardless of clinical manifestations, vacuolar degeneration at the dermoepidermal junction was found in all ECDS patients. Furthermore, melanin incontinence was seen in 11 (69%) patients. Importantly, keratinocyte necroses, which are frequently accompanied with severe vacuolar degeneration, were restricted to 2 patients with early and active lesions. Vacuolar changes in hair follicular epithelium were seen in 8 (50%) patients. Regarding the histological features in the dermis, dermal fibrosis was found in all patients, but the degree of fibrosis did not correlate with disease duration. In early ECDS patients (disease duration of < 3 years), moderate to severe perivascular and/or periappendiceal lymphocytic infiltration and vacuolar changes in follicular epithelium were prominent, while epidermal atrophy was less frequently observed, compared with late ECDS patients (disease duration of ≥ 6 years). 

Conclusion: Vacuolar degeneration at the dermoepidermal junction is a common histological feature in ECDS and perivascular and/or periappendiceal lymphocytic infiltration and vacuolar degeneration of follicular epithelium are characteristic especially in early ECDS, further supporting a canonical idea that the elimination of mutated epidermal cells by immune surveillance contributes to tissue damage and resultant fibrosis in localized scleroderma.

---

« Back to 2012 ACR/ARHP Annual Meeting

ACR Meeting Abstracts - https://acrabstracts.org/abstract/histological-features-of-localized-sclerodermaen-coup-de-sabre-a-study-of-16-cases/