Pediatric lichen planus: a systematic review of 985 published cases

Background Lichen planus (LP) is a chronic inflammatory disorder usually occurring in middle-aged adults. Data are scarce in the pediatric population. Objective To describe the patients' characteristics, clinical presentation, and management of pediatric LP. Methods A systematic literature review of pediatric LP was performed in the Medline and Cochrane databases up to February 1, 2020. Demographic and clinical data were extracted for analysis, in addition to laboratory and histology findings, treatments used, and response to treatment. LP pemphigoides (LPP) was further pooled for a subcategory analysis. Results One hundred and sixty-four articles were included representing 985 patients. The most common country of origin was India. The most common clinical signs were flat-topped papules (51%); the linear variant was present in 9%. Oral involvement was present in 22%. The most commonly used treatment was topical corticosteroids followed by systemic corticosteroids. The mean duration of treatment was 124.4 days. LPP patients had a short disease duration before diagnosis (4.1 months, P < 0.001) and failed previous treatment more frequently (P < 0.001). Systemic corticosteroids were more often prescribed in this subgroup (75%, P < 0.001) with more recurrence after treatment (31%, P = 0.048). Limitations Lack of randomized controlled studies, in addition to publication bias. Conclusion In children, LP had a wide polymorphous clinical presentation, and the reported cases were mostly from India. The linear variant was more common and the oral mucosa was less affected in children. LPP, a rare subtype in children, was treated with systemic corticosteroids and recurred more frequently.