CASE REPORTSManagement of lepirudin therapy for a patient with antiphospholipid antibody syndrome using the whole blood ecarin clot time and activated partial thromboplastin timePerry, Stephanie La; O'Shea, Susan Ia; Ortel, Thomas La,bAuthor Information aDivision of Hematology, Department of Medicine, and bDepartment of Pathology, Duke University Medical Center, Durham, North Carolina, USA. Supported by a Blood Banking and Related Areas Training Grant (T32-HL07057-25) from the National Institutes of Health (NIH) (S.L.P.), a research contract from Pharmanetics, Inc. (T.L.O.), and a Midcareer Investigator Award in Patient-Oriented Research (K24 AI0160301) from the NIH (T.L.O.). Correspondence and requests for reprints to Stephanie L. Perry, MD, Box 3422, Division of Hematology, Duke University Medical Center, Durham, NC 27710, USA. Tel: +1 919 684 5350; fax: +1 919 681 6160; e-mail: email@example.com Received 27 November 2002 Revised 7 March 2003 Accepted 18 March 2003 Blood Coagulation & Fibrinolysis: September 2003 - Volume 14 - Issue 6 - p 601-604 Buy Abstract A patient with antiphospholipid antibody syndrome (APS) and a history of heparin-induced thrombocytopenia required lepirudin therapy. The patient had an abnormal baseline activated partial thromboplastin time (aPTT), complicating management of his therapy. We investigated whether an alternative monitoring system, using a dry reagent technology [Thrombolytic Assessment System (TAS)], could be used to monitor the patient's whole blood ecarin clot time (ECT) and aPTT. Baseline values for the ECT and aPTT were normal with this system. During a continuous infusion of lepirudin, the patient's whole blood ECT was maintained between a desired range of 150–200 s for 73% of the time. Similarly, his whole blood aPTT was maintained between 60 and 80 s for 80% of the time. In contrast, the patient's plasma-based aPTT by standard methods was consistently > 150 s. The patient underwent surgical procedures without complications. To further investigate the finding that the patient's antibody did not affect the aPTT with this system, we performed the ECT and the aPTT assays on the TAS Analyzer with plasma samples from 10 patients with APS and abnormal aPTTs. All 10 samples had plasma ECT values within the normal range. Four patients had normalization of the aPTT, suggesting that a subset of patients with APS may benefit from the TAS aPTT assay when monitoring heparin or other anticoagulation therapy. © 2003 Lippincott Williams & Wilkins, Inc.