Impact of an Immunoglobulin G–Specific Enzyme‐Linked Immunosorbent Assay on the Management of Heparin‐Induced Thrombocytopenia. Issue 11 (27th June 2013)

• Record Type: Journal Article
• Authors: Sylvester, Katelyn W.; Fanikos, John; Anger, Kevin E.; Matta, Lina; Southard, Robert A.; Beik, Nahal; Lemire, Susan J.; Dorfman, David M.; Berliner, Nancy
• Is Part Of: Pharmacotherapy. Volume 33:Issue 11(2013)
• Page Start: 1191
• Page End: 1198
• Publication Date: 2013-06-27
• Subjects: heparin‐induced thrombocytopenia -- immunoglobulin G antibody -- enzyme‐linked immunosorbent assay; Chemotherapy -- Periodicals; Pharmacology -- Periodicals; Drug Therapy -- Periodicals; Pharmacology -- Periodicals; 615.1
• DOI: 10.1002/phar.1322
• Languages: English
• ISSNs: 0277-0008

Abstract

Abstract : Study Objective: To evaluate whether using an immunoglobulin G (IgG)‐specific platelet factor 4 (PF4) test reduces the rate of positive PF4 results and has an impact on prescribing practices of nonheparin anticoagulants (direct thrombin inhibitors and fondaparinux) in patients assessed for heparin‐induced thrombocytopenia (HIT). Design: Single‐center prospective cohort study with a historical control group. Setting: Large academic medical center. Patients: A total of 672 patients assessed for HIT. Intervention: Patients were assessed for HIT by using either an IgG‐specific PF4 enzyme‐linked immunosorbent assay (ELISA; 336 patients) or a nonspecific PF4 ELISA (336 patients; historical control group). Measurements and Main Results: No significant difference was noted in the proportion of patients with a low, intermediate, or high risk of HIT based on the 4Ts pretest clinical scoring system. The PF4 ELISA was positive in 6.9% versus 11.3% of patients (p=0.04) in the IgG‐specific and nonspecific cohorts, respectively. A smaller proportion of patients were prescribed a direct thrombin inhibitor in the IgG‐specific cohort (19.4% vs 25.9%; p=0.04). No significant difference in fondaparinux use was noted between the cohorts. The duration of direct thrombin inhibitor therapy, bleeding events, hospital length of stay, and in‐hospital mortality was similar in both cohorts. Conclusion: Use of an IgG‐specific PF4 ELISA was associated with a lower rate of positive PF4 test results. Direct thrombin inhibitor prescribing was also significantly lower during the time period where the IgG‐specific PF4 ELISA was used, with no significant differences noted in safety outcomes.