Schamberg's Disease; The Clinical and Histopathological Findings in Favor of Stasis Vasculitis

Abstract

Background: Schamberg’s disease is the most common type of pigmented purpuric dermatosis, that is characterized by a benign course with reddish-brown patches or macules with overlaying purpuric spots resembling a cayenne pepper. It is not uncommon condition, but the available information regarding its epidemiological, clinical, and histopathological features are very limited. Objective: To evaluate the clinical and histopathological features of Schamberg’s disease trying to have more insight into its etiopathogenesis. Patients and methods: A descriptive cross sectional study was conducted in the Center of Dermatology and Venereology, Medical City, Baghdad, Iraq, during the period from October 2018 to March 2020. Fifty patients with clinical features of Schamberg’s disease were included. The demographic features were recorded. Full history and dermatological examination were carried out. Histopathological analysis of skin biopsies that stained by H&E and Perl stains were performed for 11 patients. Results: 50 patients were included with mean age of 47.22 ± 11.8 years. 76% were males and 24% were females.  The lesions were symmetrical and consisted of macules (44%) , petechiae and  macules (32%).  Histopathological examination showed normal stratum corneum in 11 (100 %) , acanthosis in 18% , epidermal atrophy in 72 %,, spongiosis in 45 %, rete ridges effacement in 45%, basal layer vacuolization in 27 %. Many pathological changes in superficial dermis were observed like RBC extravasation, mostly around dilated and congested blood vessels was noted in 81%, variable perivascular lymphocytic infiltrates were seen in all 11 cases; 36% mild infiltrates, 36% moderate infiltrate and 27% extensive with fibriniod alterations in some of the sections.  These changes were suggestive of lymphocytic vasculitis. Perls stained sections revealed dermal iron deposition (Hemosiderin) with in siderophages mainly in the upper dermis in 82% , that was mild in 11% , moderate in 33% and extensive in 55% of the patients. Conclusion: Schamberg’s disease is a chronic, benign, asymptomatic disease affecting lower limbs in a symmetrical fashion with characteristic clinical and histopathological features that suggest lymphocytic vasculitis rather than capillaritis of dermis, leading into hemosiderin deposition as an outcome. These features with poor circulation do suggest that disease is a form of vasculitis that could be named stasis vasculitis as the main etiopathological finding. Keywords: pigmented purpuric dermatosis, Schamberg disease, Perl stain, hemosiderin.