A modification of the APC resistance test and its application to the study of patients on coumarin therapy.

Abstract

APC resistance appears to be caused, predominantly, by a mutation in coagulation factor V (nucleotide 1691: G to A). This phenomenon is usually studied by performing APTTs in the absence and presence of added APC. We studied a modification of the assay involving dilution of the test plasma in factor V deficient plasma, to render the assay more factor V specific. This modification was applied to 76 patients with venous thrombosis on coumarin treatment and to 45 controls. Two out of 45 controls (4.4%) showed abnormal results with the modified test. They also showed loss of factor V exon 10 Mnl I restriction site, associated to APC resistance. All remaining controls, with normal functional results by the modified assay, showed normal restriction profile. We detected 9 affected patients (11.8%), one of them homozygous or double heterozygous. In conclusion, the modified assay is very sensitive for factor V dependent APC resistance, and can successfully be applied to patients on coumarin therapy.

• Authors: J I Jorquera, J Aznar, M A Fernández, J M Montoro, R Curats, P Casaña
• Journal: Thrombosis research (Thromb Res) Vol. 82 Issue 3 Pg. 217-24 (May 01 1996) ISSN: 0049-3848 [Print] United States
• PMID: 8732625 (Publication Type: Journal Article)

Chemical References

• Anticoagulants
• Coumarins
• Protein C
• coumarin

Topics

• Adult
• Aged
• Aged, 80 and over
• Anticoagulants (therapeutic use)
• Case-Control Studies
• Coumarins (therapeutic use)
• Drug Resistance (genetics)
• Factor V Deficiency (blood, genetics)
• Humans
• Middle Aged
• Mutation
• Protein C (agonists)
• Thrombophlebitis (blood, drug therapy)