Ayesha Junaid, Suhaib Ahmed, Masood Anwar, Waqar Ali, Nasirud Din, Muhammad Ayyub, Zahur Ur Rehman.
Factor V Leiden in young patients with Thrombophilia.
J Coll Physicians Surg Pak Jan ;14(11):698-9.

This study addresses the frequency of FVL in Pakistani patients with thrombophilia. All patients with the occurrence of a venous or arterial thrombo-embolic event at an age of <45 years, reporting to any of the hospitals in Rawalpindi-Islamabad, during the period of study. Patients with a previously confirmed abnormality in coagulation/fibrinolytic pathway, oral anticoagulants intake for >6 months or suffering from any malignancy were excluded from the study. Eight ml of venous blood was collected from each patient, of which 1.8 ml was mixed with 0.2 ml tri-sodium citrate (100 mmol/l) for use in clotting tests. Remaining was equally divided in two bottles containing dipotassium EDTA and was used for blood counts and extraction of DNA. The results were considered valid only if the values of QC plasma were within the confidence range. A decreased response, normalized ratio (NR) below 0.80, is suggestive of presence of homozygous FVL mutation. FVL mutation was detected by restricted fragment length polymorphism (RFLP) for a 220 base pair (bp) (exon 10-intron 10) fragment of factor V. The fragment was amplified by polymerase chain reaction (PCR) using the following pair of primers. Amplification involved 36 cycles consisting of denaturation at 94oC for 40 seconds, annealing at 55oC for 40 seconds and extension at 71oC for 2 minutes in the presence of 2 units of Taq polymerase. A total of 46 patients with established thromboembolic disease were recruited in the study. Based on the clinical spectrum patients were divided into three groups. Group-I had DVT/pulmonary embolism (n=20), group-II had stroke (n=16) and group-III were females with recurrent fetal loss (n=10). NR with ProC Global test was abnormal (<0.80) only in patients on oral anticoagulants. All other patients had NR >0.80. Of these, only 2 were found to be heterozygotes for FVL by PCR. No homozygote was detected. The results had a sensitivity of 100% and specificity of 76%. Negative predictive value was 100% whereas positive predictive value was only 18%. In recent past resistance to APC caused by R506Q mutation in factor V gene (factor V Leiden) has come up as the most important single cause of thrombophilia having been detected in 10-60% cases of thromboembolism. This is a short communication.

PakMediNet -Pakistan's largest Database of Pakistani Medical Journals - http://www.pakmedinet.com