Hemophagocytic Lymphohistiocytosis in a Patient With Hodgkin's Lymphoma Mimicking Sinusoidal Obstructive Syndrome: A Diagnostic Challenge.

Hemophagocytic lymphohistiocytosis (HLH) is a rare, life-threatening hyperinflammatory syndrome triggered by malignancy, infection, or autoimmune disease. We present a case of a 19-year-old male with Hodgkin's lymphoma who developed high-grade fevers, hepatomegaly, and severe liver injury shortly after receiving chemotherapy. He was initially diagnosed with sinusoidal obstructive syndrome (SOS) and treated with defibrotide. Despite therapy, his condition deteriorated, prompting transfer to our institution for evaluation of acute liver failure and suspected drug-induced liver injury (DILI). Further diagnostic evaluation revealed markedly elevated serum ferritin and soluble interleukin-2 receptor (sCD25), and bone marrow biopsy demonstrated prominent hemophagocytosis. These findings confirmed the diagnosis of HLH, likely secondary to underlying Hodgkin's lymphoma and possible Epstein-Barr virus (EBV) reactivation. The patient was initiated on high-dose corticosteroids with rapid clinical and biochemical improvement. This case underscores the diagnostic complexity of HLH, particularly in lymphoma patients undergoing chemotherapy, where overlapping syndromes can delay accurate diagnosis, and highlights the critical importance of early recognition to initiate timely, life-saving immunosuppressive therapy.