Nafamostat Mesilate as an Anticoagulation Strategy for Heparin-Induced Thrombocytopenia

Introduction: Heparin-induced thrombocytopenia (HIT) is a life-threatening complication of heparin exposure, occurring in 0.1%–5% of patients, with end-stage renal disease (ESRD) patients at higher risk due to frequent heparin use. HIT Type II, an immune-mediated condition, results from antibodies against heparin/platelet factor 4 (PF4) complexes, leading to platelet activation and thromboembolism. Case Description: We present a 78-year-old woman with ESRD who developed HIT Type II after low-molecular-weight heparin (LMWH) and unfractionated heparin (UFH) exposure during hemodialysis. Despite a negative PF4/heparin ELISA, a 4T score of 7 confirmed clinical HIT. She experienced thrombocytopenia (30×10*9/L) and sever thrombotic events. Heparin was discontinued, and anticoagulation transitioned to argatroban and later nafamostat mesilate due to argatroban shortage. Platelet counts normalized (223×10*9/L), and nafamostat mesilate was effective without clotting complications. Discussion: This case highlights the challenges in HIT diagnosis, emphasizing the role of clinical evaluation over laboratory tests, and underscores the utility of nafamostat mesilate as an alternative anticoagulant in resource-limited settings. Key questions remain regarding heparin rechallenge safety, causative agent identification in multi-heparin exposure, and rapid differentiation of HIT from anaphylactoid reactions. Further studies are needed to optimize HIT management in high-risk populations.