Hemophagocytic Lymphohistiocytosis in Renal Transplant Recipients: A 2-Case Report.

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening syndrome characterized by an excessive immune activation. HLH can be triggered by a variety of events that disrupt immune homeostasis, such as infections and immunosuppression. HLH presents with heterogeneous clinical symptoms and laboratory findings such as pancytopenia, elevated liver enzymes, impaired renal function, and hyperferritinemia.Case 1. A 58-year-old man was admitted because of a high fever and diarrhea. Laboratory findings showed acute renal impairment, pancytopenia, Epstein-Barr virus (EBV) DNA seropositivity with a replication index of 2 million copies/mL, and hyperferritinemia. A diagnosis of HLH was confirmed by bone marrow aspiration. He was treated with etoposide, steroids, and rituximab with initial good response and good kidney function restoration. He was discharged after 31 days but eventually died after 44 days after a disease relapse. Case 2. A 51-year-old kidney transplant recipient was admitted because of a fever of unknown origin. A worsening renal function, pancytopenia, EBV DNA of 4,356,222 copies/mL on blood, D-Dimer 7505 ng/mL, ferritinemia 9180.9 ug/L, and triglycerides 1273 mg/dL were found. Bone marrow aspiration was negative for HLH; a few days later, a diagnosis of HLH was made after a positive bone marrow biopsy. Continuous renal replacement therapy was started in the intensive care unit because of severe lactic acidosis due to sepsis. She died few days later.EBV infection could be a trigger for HLH in a renal transplant patient. Hyperferritinemia is useful for differential diagnosis in a septic patient. The outcome is very poor even with prompt treatment.