Pediatric Systemic Lupus Erythematosus Complicated by Acute <scp>EBV</scp> and <scp>CMV</scp> Co‐infection

BACKGROUND: Systemic lupus erythematosus (SLE) is a multifactorial autoimmune disease characterized by multi-organ damage, with genetic, environmental, and viral factors implicated in its pathogenesis. Herpesviruses such as Epstein-Barr virus (EBV) and cytomegalovirus (CMV) are known to trigger or exacerbate SLE, potentially through mechanisms like molecular mimicry and immune dysregulation. CASE PRESENTATION: We report the case of a 10-year-old girl who presented with a malar rash following sun exposure, accompanied by fever and arthritis. Laboratory investigations revealed the presence of multiple autoantibodies and serological evidence of active co-infection with both EBV and CMV. A diagnosis of SLE with mild activity was established. The patient received intravenous methylprednisolone, belimumab, and oral ganciclovir. This led to significant clinical improvement, including resolution of the facial rash and normalization of joint mobility. Follow-up assessments showed near-complete normalization of inflammatory markers and autoantibody titers. However, causality cannot be established from a single case, and proposed mechanisms remain hypotheses. CONCLUSION: This case suggests that acute co-infection with EBV and CMV may play a role in the pathogenesis of SLE, possibly via molecular mimicry and B-cell activation. Therefore, routine screening for EBV and CMV in adolescent SLE patients may be warranted to advance etiological research and inform personalized treatment strategies.