Coexistence of nail psoriasis and cutaneous lichen planus in a single patient: An uncommon entity

Psoriasis and lichen planus (LP) are common, routinely encountered autoimmune disorders. However, their coexistence is relatively uncommon. Both diseases have an autoimmune and complex genetic background. There are few case reports on the coexistence of LP and psoriasis vulgaris. However, to the best of our knowledge, there are no case reports on the coexistence of nail psoriasis and cutaneous LP. Many speculations have been put forward about the pathogenesis of their coexistence in a single patient. However, certain genetic predispositions, T-cell-mediated autoimmunity, and true Koebner phenomenon play a significant role in disease development. We present the details of a patient with isolated nail psoriasis who subsequently developed cutaneous and oral LP. Awareness of such a possibility can help avoid misdiagnosis in clinical practice.