TOPICAL THROMBIN AND ACQUIRED COAGULATION-FACTOR INHIBITORS - CLINICAL SPECTRUM AND LABORATORY DIAGNOSIS

Topical bovine thrombin preparations are used extensively in cardiovas cular, neurosurgical, and otolaryngologic procedures. Patients who are treated with these topical thrombin preparations may develop antibodi es to bovine coagulation factors that may cross-react with the endogen ous human clotting proteins. We have identified four patients with acq uired factor inhibitors following exposure to topical thrombin at Duke University Medical Center and summarize these cases in addition to 13 patients previously reported in the literature. In most cases, the in hibitor developed following a second (or subsequent) exposure to topic al thrombin. The clinical course was extremely variable, ranging from totally asymptomatic to life-threatening hemorrhage. The most consiste nt laboratory abnormality was a prolonged bovine thrombin clotting tim e, which corrected, at least partially, when human thrombin was substi tuted for bovine thrombin. Some of these patients also developed facto r V inhibitors with prolonged prothrombin and activated partial thromb oplastin times. Although these patients have prolonged clotting times, they should not be considered ''autoanticoagulated,'' since thromboem bolic complications can still occur. Therapeutic intervention is large ly empirical and depends on the clinical manifestations of the individ ual patient. (C) 1994 Wiley-Liss, Inc.