Pitfalls in Warfarin Therapy

摘要

The article in this issue of the journal by Abdul-Jabar and colleagues entitled "Warfarin-Induced Skin Necrosis: A Case Report" draws our attention to a rare and devastating complication of warfarin therapy. Because the problem is likely to be reasonably well known to readers of this journal, but less so to readers of journals less dedicated to thrombosis and hemostasis, why publish it here? As much as we may think we know about this problem, we find there are a number of thought-provoking aspects to warrant our attention and to make us aware of the fact that seemingly small oversights in management can result in medical disasters. As we read the report, we first note that this relatively young Asian man had no apparent risk factors for deep vein thrombosis, yet there is little doubt that he had it along with claudication, probably of the vascular type. Was he a tobacco user? What about thromboangiitis obliterans (Buerger's disease) or protein C deficiency? These diagnoses should not deter us from initiating heparin or low-molecular-weight heparin therapy, but there might be a hazard to starting warfarin simultaneously, and it is prudent to draw blood samples for subsequent testing for inherited risk factors (1). Age of the patient and lack of clinical risk factors as well as chronicity are indications of the presence of a hereditary risk factor. It may surprise some to find that peripheral vascular disease with or without evidence of atherosclerosis may be associated with long segments of arterial narrowing in patients with protein C or S deficiency (2). The report shows that this patient did in fact have peripheral vascular disease but provides no proof of atherosclerosis.