RESUMEN
BACKGROUND: Pediatric discoid lupus erythematosus (DLE) is rare. The risk of progression to systemic lupus erythematosus (SLE) is uncertain. OBJECTIVE: We sought to determine the risk of progression of pediatric DLE to SLE and to characterize its phenotype. METHODS: This was a retrospective review of 40 patients with DLE. RESULTS: Six (15%) of 40 patients presented with DLE as a manifestation of concurrent SLE. Of the remaining 34, 9 (26%) eventually met SLE criteria and 15 (44%) developed laboratory abnormalities without meeting SLE criteria. Only 10 (29%) maintained skin-limited disease. The average age at progression to SLE was 11 years, with greatest risk in the first year after DLE diagnosis. Most (89%) patients with SLE met diagnostic criteria with mucocutaneous disease (discoid lesions, malar rash, oral and nasal ulcers, photosensitivity), positive antibodies, and/or cytopenia without developing end-organ damage over 5 years of median follow-up. LIMITATIONS: The study was retrospective. CONCLUSIONS: In pediatric patients, DLE carries a significant risk of progression to SLE but may predict a milder phenotype of systemic disease. All patients require careful monitoring for SLE, particularly within the first year of diagnosis.