Abstract
Heparin-induced thrombocytopenia (HIT) is an immune response to heparin that can progress
to severe thrombosis, amputation, and in some cases death. The diagnosis and treatment
of HIT is complex, but needs to be considered in the clinical management of patients
exposed to heparin due to its serious outcomes. Early diagnosis based on a comprehensive
interpretation of clinical and laboratory information improves clinical outcomes.
This begins with careful monitoring for thrombocytopenia and thrombosis during and
for at least 5 to 10 days after heparin treatment of any dose and duration. Appropriate
use and knowledgeable interpretation of laboratory tests for HIT are important, as
these vary in sensitivity and specificity, with each type providing unique information.
Clinical management of patients with HIT is with a non-heparin anticoagulant such
as a direct thrombin inhibitor or danaparoid followed by a vitamin K antagonist for
long-term treatment. Important drug-specific limitations, dosing, and monitoring guidelines
must be respected for patient safety. There continues to be new developments in the
field of HIT: laboratory testing, clinical scoring systems, and available new anticoagulants.
Research and clinical studies will continue to address the unresolved issues and unmet
clinical needs associated with HIT. This review summarizes the clinical management
of HIT.
Keywords
heparin-induced thrombocytopenia - antibody assays - anticoagulants - thrombin inhibitor
