ABSTRACT
Zoon's plasma cell mucositis (ZM) is a benign inflammatory process that may involve the external genitalia with a chronic-relapsing course in males and females. The exact etiopathogenesis of ZM is unknown, but suggested predisposing factors include warmth, friction, poor hygiene, chronic irritation and/or infections. The diagnosis of ZM is often challenging due to clinical similarities with other genital dermatoses. In particular, the main differential diagnoses include erythroplasia of Queyrat, genital infections, inflammatory diseases, bullous diseases and drug fixed eruption. The diagnosis of ZM, in case of typical presentation, may be clinical and supported by dermoscopy. Recently, reflectance confocal microscopy has been reported to assist the diagnosis of ZM by revealing a normal nucleated epidermal honeycomb pattern, small bright cells, histologically corresponding to the inflammatory infiltrate in the upper dermis, and tortuous vessels running parallel to the surface at the epithelium-lamina propria junction.
