Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis in pediatric-onset Crohn’s disease patients

Epstein-Barr virus (EBV)-associated hemophagocytic lymphohistiocytosis (HLH) is an uncommon yet life-threatening complication in immunocompromised individuals.Herein, we present a case of EBV-HLH in a 19-year-old woman with pediatric-onset Crohn's disease (CD) who had been receiving long-term azathioprine therapy.Initially treated for a presumed CD flare, the patient developed sustained high-grade fever, cytopenia, hyperferritinemia, and positive EBV serologies, which prompted further evaluation.She met the HLH-2004 diagnostic criteria and was treated with dexamethasone, cyclosporine, etoposide, and rituximab.Cyclosporine-induced posterior reversible encephalopathy syndrome (PRES) required modification of the immunosuppressive regimen.Ultimately, the patient achieved hematological recovery.This case underscores the importance of timely recognition of HLH in pediatric-onset inflammatory bowel disease, particularly in patients receiving thiopurines.Pre-treatment EBV serological screening and interdisciplinary collaboration are essential to reduce morbidity and optimize care in this vulnerable population.