Diagnostic Difficulties of Erosive Lichen Planus in a Pediatric Patient.

Lichen planus (LP) is a chronic inflammatory disease that can present with significant morbidity, particularly in children. Erosive lichen planus (ELP), its rare destructive subtype, can be particularly difficult to diagnose and manage. We present a rare pediatric case of ELP with multisite involvement and discuss the differential diagnosis. A 12-year-old boy presented with painful erosions and ulcers on the lateral tongue and dystrophic nails. His six-year history of tongue and nail lesions prompted several comprehensive examinations. Laboratory tests did not reveal any abnormalities. Histopathological examination of the tongue lesions was representative of ELP. Line-field confocal optical coherence tomography (LC-OCT) examination of the tongue lesions showed features that strongly correlated with histopathology. The patient was later hospitalized due to dysphagia and esophageal food impaction, during which esophageal ELP was confirmed. The patient was initially managed with topical corticosteroids. He was later started on systemic therapy in the form of methotrexate and low-dose naltrexone to address his symptoms and disease presentation. This case highlights the complexities of diagnosis and management of ELP in pediatric patients. A multidisciplinary approach and regular follow-up are necessary to manage symptoms, prevent complications, and improve quality of life.