The Treatment Effect of Protamine on Severe Coagulopathy in Epstein-Barr Virus-Associated Hemophagocytic Lymphohistiocytosis: Case Reports and Literature Review.

Hemophagocytic lymphohistiocytosis (HLH) is a rare and life-threatening disease, which is characterized by severe systemic inflammation with cytokine storm as well as histologic evidence of hemophagocytosis. Besides, coagulopathy and hemorrhages are two common severe complications in HLH patients. Recent literatures indicate that Epstein-Barr virus (EBV) infection is one of the important triggers for the disease. In the study, we present three cases of EBV related HLH (EBV-HLH) with coagulopathy in patients with distinct backgrounds. Case 1 is a 45-year-old female diagnosed with EBV associated NK/T cell lymphoproliferative disorder (EBV-T/NK-LPD) and EBV-HLH. Case 2 is a 17-year-old male with a diagnosis of EBV-T-LPD and EBV-HLH. Case 3 is a 51-year-old male and also diagnosed with EBV-T-LPD and EBV-HLH. All cases were given with treatment with HLH-94 protocol, and the symptoms of the three patients improved. Furthermore, during the treatment, protamine, which has not been reported in the literature previously, was given to the three cases with EBV-HLH, and our results showed that after treatment with protamine, the coagulopathy and bleedings in these patients were improved rapidly. Unfortunately, the three patients relapsed soon and died despite intensive treatment. However, these cases suggest that protamine may serve as a potential treatment option for coagulation associated with EBV-HLH. Besides, the study helps us improve the understanding of the EBV-HLH related coagulation disorders, and provide a potential strategy for future treatment of the disease.