Background: Juvenile rhupus syndrome is the coexistence of juvenile idiopathic arthritis (JIA) and systemic lupus erythematosus (SLE) in a pediatric patient. It is a rare but clinically significant autoimmune overlap syndrome. Case: We present a case of a 10-year-old girl (initially diagnosed with rheumatoid factor-positive polyarticular JIA and being treated with methotrexate) who developed features suggestive of an SLE flare-up and/or methotrexate toxicity, including pallor, non-scarring alopecia, dyspnea, pancytopenia, impaired liver function tests, and restricted mobility in the elbow and knee joints; however, laboratory reports indicated elevated antinuclear antibody and anti-double-stranded DNA antibodies titers, as well as decreased complement levels. After thorough clinical assessment and excluding other potential causes, she fulfilled the 2019 European League Against Rheumatism /American College of Rheumatology criteria for SLE diagnosis, leading to the diagnosis of juvenile rhupus syndrome. Such disease evolution required therapeutic reassessment, and her immunosuppressive regimen was revised. Conclusion: Rhupus syndrome is just as significant in children as it is in adults, where it is more commonly reported. Early recognition and adequate therapy are essential for improved clinical outcomes as juvenile rhupus often shows severe systemic involvement and increased morbidity compared to isolated JIA or SLE. Our case contributes to the limited literature on juvenile rhupus and highlights the need for clear diagnostic criteria and management guidelines.
Abedeen et al. (Fri,) studied this question.