The natural history of pediatric-onset discoid lupus erythematosus

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.