Pityriasis Lichenoides Chronica: A Diagnostic and Therapeutic Challenge

Pityriasis lichenoides (PL) is an uncommon, acquired inflammatory skin disorder that presents considerable diagnostic and therapeutic challenges. Its classification, natural history, and optimal management remain subjects of debate. PL is best conceptualized as a clinical spectrum encompassing pityriasis lichenoides et varioliformis acuta (PLEVA), pityriasis lichenoides chronica (PLC), and the rare febrile ulceronecrotic Mucha-Habermann disease (FUMHD). Whether these represent truly distinct entities or points along a single continuum remains controversial, given their overlapping clinical, histopathological, and etiological features. PLC typically manifests as an insidious eruption of small, red-to-brown, flat-topped papules bearing a characteristic adherent mica-like scale, following a relapsing-remitting course with prolonged periods of quiescence. We report a case of longstanding PLC in a 60-year-old woman who was successfully managed with a combination of methotrexate, topical corticosteroids, keratolytics, and emollients, achieving sustained remission at six-month follow-up.