Antibody-induced arterial thromboembolism resulting in amputation after total knee arthroplasty.

Heparin-induced thrombocytopenia is a rare drug reaction that can be associated with thrombotic complications leading to myocardial infarct, stroke, or ischemic loss of a limb. Because of the broadening indications of low-molecular-weight heparin use, the current emphasis on ambulatory care, and the difficulty in clinical diagnosis and treatment of this drug reaction, heparin-induced thrombocytopenia is the most important allergic drug reaction that physicians must manage. An antibody-mediated drug reaction to low-molecular-weight heparin that resulted in a below-knee amputation after an elective total knee arthroplasty is reported.