Genital psoriasis coexisting with oral lichen planus – A diagnostic dilemma differentiated by dermoscopic evaluation: A case report

Immunological pathways play a major role in inflammatory skin conditions including lichen planus (LP) and psoriasis. Both diseases are categorized as papulosquamous disorders; they both show abnormal keratinocyte differentiation and can develop lesions in response to skin traumas or scratching (a phenomenon called the Koebner phenomenon). Despite these similarities, significant differences in distribution, immunological responses, histological features, and associations with major histocompatibility antigens suggest that distinct mechanisms underlie the pathogenesis of these two diseases. Psoriasis and LP coexistence is not unusual, but it has been documented infrequently. In this report, we present a case of genital psoriasis coexisting with oral LP in a patient, which was clinically diagnosed, evaluated and differentiated through dermoscopy, thereby eliminating the necessity for histopathological examination.