58 | early cocaine-induced periorificial dermatomucositis: A case series expanding the clinicopathological spectrum beyond midline destructive lesions

Introduction. Cocaine-induced midline destructive lesions (CIMDL) are a well-recognized complication of chronic intranasal cocaine use. However, dermatologists are increasingly encountering earlier mucocutaneous manifestations without osteocartilaginous destruction. We aimed to characterize the clinical and histopathological features of these early lesions and to explore their relationship with the emerging concept of cocaine-induced plasma cell dermatomucositis (cPCDM).Materials and Methods. We retrospectively reviewed seven patients presenting with persistent ulcerative lesions involving periorificial sites. Clinical, laboratory, histopathological, microbiological, and radiological findings were collected. Cocaine exposure was confirmed through repeated clinical interviews.Results. Six patients presented with ulcerative lesions involving the nasal or perinasal region without evidence of cartilage or bone destruction, whereas one patient developed a painful and unusual perianal ulcer following topical cocaine application. Histopathological examination of biopsy specimens from all patients consistently showed ulceration and necrosis associated with mixed inflammatory infiltrates rich in plasma cells, neutrophils, and eosinophils, without the granulomas and destructive vasculitis typical of granulomatosis with polyangiitis. p-ANCA positivity was observed in two cases. Cocaine use was initially denied by most patients and only disclosed after repeated questioning. Clinical improvement or complete resolution occurred following cocaine withdrawal in patients with available follow-up.Conclusions. Early cPCDM should be considered in the differential diagnosis of persistent periorificial ulcerative lesions of unclear origin. Our findings support the concept of cPCDM as an early clinicopathological manifestation within the spectrum of cocaine-related injury and expand its presentation to include atypical periorificial sites, such as the perianal region. Prompt recognition may prevent progression to destructive disease, avoid unnecessary immunosuppressive treatments, and facilitate timely counselling regarding cocaine cessation.