Pediatric Discoid Lupus Erythematosus: Risk of Progression to Systemic Lupus Erythematosus and Disease Phenotype
Researchers at the Northwestern University Feinberg School of Medicine in Chicago recently characterized the risk of progression from discoid lupus erythematosus (DLE) to systemic lupus erythematosus (SLE) in children, and the disease phenotype. The study entitled “The natural history of pediatric-onset discoid lupus erythematosus” was published in the Journal of the American Academy of Dermatology.
SLE is a severe autoimmune disease in which the body’s own immune system overreacts and attacks healthy joints and organs, resulting in inflammation, swelling, pain, disability and often in tissue destruction. Around 20% of all SLE cases appear during the first 20 years of life, with pediatric SLE usually proving more severe when compared to adult SLE where individuals experience a higher frequency of end-organ involvement, a requirement for continued immunosuppression and a higher mortality.
DLE corresponds to a chronic, photosensitive, cutaneous form of the disease that can be either localized (confined to the head and neck) or widespread (involving the entire body) and is characterized by scaly plaques with prominent follicular plugging, atrophy, depigmentation, and discoid scarring. In adults, it has been reported that the frequency of progression from DLE to SLE varies between 0 and 28%, and this progression can occur within months to decades. In children, DLE is a rare condition, and less than 3% of the DLE pediatric cases are developed before the age of 10. The natural history of pediatric-onset DLE is poorly understood.
It has been previously reported that children with DLE seem to have a higher early rate of progression to SLE (up to 25%) indicating that the age at onset might influence disease severity and the pattern of organ involvement. The goal of this study was to characterize in more detail pediatric DLE and determine the associated risk of progression to SLE.
Researchers conducted a retrospective review of 40 DLE patients diagnosed before the age of 16 years between 1995 and 2012 at the Ann and Robert H. Lurie Children’s Hospital of Chicago.
The team found that of the 40 patients, 15% (six patients) had DLE as a manifestation of coexistent SLE. Of the remaining patients, 26% eventually progressed and met the 1982 SLE criteria from the American College of Rheumatology (ACR), 44% developed laboratory anomalies without meeting the criteria for SLE diagnosis, and 29% maintained skin-limited disease. The average age at progression from DLE to SLE was 11 years, with the risk becoming higher in the first year after DLE diagnosis. The majority of patients who developed SLE (89%) exhibited positive antibodies, mucocutaneous disease (like malar rash, discoid lesions, oral and nasal ulcers, photosensitivity), and/or cytopenia (reduction in the number of blood cells); none of these patients developed end-organ damage in the median follow-up period of 5 years, indicating a mild systemic disease.
The research team concluded that pediatric DLE has a significant risk of progression to SLE, although the overall systemic disease phenotype developed seems to be milder. The researchers suggest that further long-term prospective studies of pediatric DLE patients with a follow-up to adulthood are required in order to fully characterize this disease in children.