Heparin-Induced Thrombocytopenia in Chronic Hemodialysis Patients

Abstract

Heparin-induced thrombocytopenia (HIT) is a disorder originating from exposure to heparin and has a spectrum of presentation ranging from asymptomatic positive antibodies to thrombotic complications. When symptomatic, it is associated with morbidity and mortality. The incidence of HIT in the ESRD population is yet to be defined. End-stage renal disease (ESRD) patients are at particular risk due to constant exposure to heparin. The main treatment of HIT is to avoid heparin and pursue alternative anticoagulants. Since 1 of the main advantages of heparin in ESRD patients is the ease of its use due to non-renal clearance, the use of alternative anticoagulants poses yet another challenge for this population due to cost, availability, and adverse effects on ESRD patients. Argatroban seems like the best alternative to heparin in hemodialysis (HD) patients due to its liver clearance. Despite having limited studies in HIT, direct oral anticoagulants (DOACs) were added as a potential treatment for HIT, with apixaban favored in kidney dysfunction as it is the least dependent on kidney clearance. Other treatment modalities exist but are still being studied in ESRD patients. The presence of HIT antibodies is not always associated with clinical syndrome, and some studies suggested that heparin antibodies are transient, and the reintroduction of heparin is still being evaluated as a treatment option. Hence, HIT is a challenging diagnosis in ESRD patients, a population that has frequent exposure to anticoagulants, and a risk/benefit ratio should be weighed between the risk of progression to symptomatic HIT and the benefit of switching to a non-heparin anticoagulant bearing in mind the difficulties associated with the latter.

Keywords: anticoagulants; coagulation; coagulopathy; direct oral anticoagulants; hemodialysis; heparin-induced thrombocytopenia.