Abstract

This abstract demonstrates the distribution of hypercoagulation diagnosis among patients with histories of thromboembolic disease (TED) among a group of patients detected at surgery prescreening clinic or through other referral sources. The consulting hematologists determined which laboratory tests were ordered; thus not all patients had all tests. This abstract describes the results of those clinical consultations. For this study the hospital’s computer logs were probed for patients having had measurements of protein C and factor V Leiden from 11/7/01until 8/1/07. The laboratory records of identified patients were searched for additional hypercoagulation laboratory parameters. A total of 383 patients have been identified, among whom abnormal diagnostic results were found for 231. Genomic assays were performed often for the commonly found defects (i.e., factor V Leiden and prothrombin 20210) and selectively for other situations, such 4G/5G for patients with elevated plasminogen activator inhibitor 1 (PAI-1) and unresolved venous thrombus, or methylene tetrahydrofolate (MTH) reductace for unexplained elevation of homocysteine. The table demonstrate the distribution of these laboratory diagnoses. The risk of having TED associated with these results will be stratified to emphasize the increased risk associated with the more severe abnormalities of protein C, protein S, ATIII, PAI-1, and homocysteine. These results demonstrate that laboratory explanations for TED may be found in a large proportion of patients with TED, which thereafter can be used to design prophylactic programs for at risk patients upon entry to hospital, especially elective surgery.

Hypercoagulation Parameters

PatientsProtein C* (<60%)Protein S* (<60%)AT III (<80%)Homocysteine (>12 um/L)Lupus anticoagulantAnti-phospholipid syndrome**
* excludes patients taking warfarin; includes functional and antigen assays. ** combines anticardiolipin; anti-beta2, glycoprotein1; and anti-phosphotidyl -serine, -ethanolamine and -choline antibodies. 
total n 350 358 244 252 166 234 
abnormal n (%) 7(2) 64(18) 29 (12) 89(35) 18 (11) 41 (18) 
PAI-1 (>42) ng/ml) APC Resistance (<2.1) VIII:c & VIII:vW (>180%) Factor V Leiden Prothrombin 20210 MTH Folate Reductace 4G/5G 
36 75 61 225 219 10 
22 (61) 10 (13) 11 (18) 37 (16) 16 (7) 8 (80) 8 (90) 
PatientsProtein C* (<60%)Protein S* (<60%)AT III (<80%)Homocysteine (>12 um/L)Lupus anticoagulantAnti-phospholipid syndrome**
* excludes patients taking warfarin; includes functional and antigen assays. ** combines anticardiolipin; anti-beta2, glycoprotein1; and anti-phosphotidyl -serine, -ethanolamine and -choline antibodies. 
total n 350 358 244 252 166 234 
abnormal n (%) 7(2) 64(18) 29 (12) 89(35) 18 (11) 41 (18) 
PAI-1 (>42) ng/ml) APC Resistance (<2.1) VIII:c & VIII:vW (>180%) Factor V Leiden Prothrombin 20210 MTH Folate Reductace 4G/5G 
36 75 61 225 219 10 
22 (61) 10 (13) 11 (18) 37 (16) 16 (7) 8 (80) 8 (90) 

Author notes

Disclosure:Research Funding: Foundation for Hematology Research.