I believe the letter writer has misinterpreted my statement on treatment of HIT. Some of that may be due to the column's major focus (wound care); for example, I didn't distinguish type I and type II HIT syndromes because of space constraints. 1, 2
It's not entirely correct to say warfarin is "contraindicated in patients with acute HIT because of the initial prothrombotic effects of warfarin-induced protein C deficiency." Warfarin is contraindicated in acute HIT when it's used as monotherapy.3-5 In fact, initial treatment of HIT should involve, as Ms. Housholder-Hughes notes, the use of either argatroban or lepirudin.
The national guideline, Heparin and Low-Molecular-Weight Heparin: Mechanisms of Action, Pharmacokinetics, Dosing, Monitoring, Efficacy, and Safety, states "warfarin appears to be safe in acute [HIT] when it is given to a patient who is adequately anticoagulated with a drug that reduces thrombin generation in [HIT], such as danaparoid [Orgaran], lepirudin, or argatroban, although it may be prudent to delay starting warfarin therapy until the platelet count has risen above 100 x 109/L." 6 I didn't specifically include these direct thrombin inhibitors' names when discussing the need for heparin cessation and the "initiation of some other form of anticoagulation", perhaps adding to the confusion.
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