Pityriasis Lichenoides in Children: A Clinical Update on Pathogenesis, Clinicopathological Spectrum, Diagnosis, and Management

Pityriasis lichenoides (PL) is an acquired papulosquamous disorder that primarily affects children and young adults.Its clinical spectrum encompasses pityriasis lichenoides chronica, pityriasis lichenoides et varioliformis acuta, mixed phenotypes, and the potentially fatal febrile ulceronecrotic Mucha-Habermann disease.Diagnosis may be challenging because clinical morphology and histopathological findings vary with lesion stage and overlap with infectious, inflammatory, and lymphoproliferative disorders.This narrative review summarizes current evidence on epidemiology, pathogenesis, clinicopathological features, dermoscopy, differential diagnosis, treatment, prognosis, and follow-up of pediatric PL.Histopathological findings are stage dependent.PLEVA typically shows parakeratosis, basal vacuolar change, necrotic keratinocytes, lymphocytic exocytosis, erythrocyte extravasation, and a superficial-to-deep wedge-shaped lymphohistiocytic infiltrate, whereas PLC shows overlapping but generally subtler changes, including focal parakeratosis, milder interface injury, a more superficial infiltrate, and less epidermal necrosis.Diagnosis depends on clinicopathological correlation; dermoscopy is supportive, whereas immunophenotyping and clonality studies are reserved for selected cases.Prognosis is usually favorable despite a prolonged or relapsing course.Management should reflect disease activity, symptoms, extent, scarring risk, and treatment burden.Observation and topical therapy are appropriate for limited disease, macrolides and narrowband ultraviolet B are used for persistent or widespread disease, and methotrexate is the best-described steroid-sparing systemic option for refractory or high-burden PL, although comparative pediatric evidence is lacking.A spectrum-based, risk-stratified approach may help avoid both undertreatment and unnecessary escalation.