Impact of inherited thrombophilia on the risk of recurrent venous thromboembolism onset in Georgian population.

Inherited thrombophilia means a predisposition of an individual to thrombosis caused by genetic disorders of homeostasis system. Purpose of the conducted study was to establish the role of point mutations of prothrombin (PGM) - 20210G/A; Factor V Leiden (FVL) - 1691G/A and methylenetetrahydrofolate reductase (MTHFR) - 677C/T genes, i.e. inherited thrombophilia in the pathogenesis of primary and recurrent venous thromboembolism in patients of the Georgian population. The above mentioned mutations were detected by PCR and single nucleotide primer extension reaction, followed by Enzyme Linked Immuno-Sorbent Assay (ELISA) in 93 patients with venous thromboembolism, out of which: 56 patients were diagnosed with unprovoked, primary thromboembolism confirmed by objective studies and 37 patients were diagnosed with recurrent thromboembolism. According to statistical analysis of the results, incidence of FVL mutation in the group of patients with recurrent thrombosis was significantly higher compared to patients with primary thrombosis - respectively 0.21 and 0.44 (p=0.0164<0.05). It should also be mentioned that homozygous carriage of FVL mutation was confirmed only with patients having recurrent thrombosis. Similar tendency was observed during study of prothrombin gene; however the difference was not statistically significant. Similar tendencies were not observed in case of homozygous carriage of MTHFR gene C677T mutation. Double and triple heterozygous/homozygous carriage of studied mutations (total of 20 cases) was observed in patients of both groups. Distribution of these genotypes in the recurrent thrombosis group was higher compared to patients with primary thrombosis - respectively 27% and 17.9%. Herewith, it should be mentioned that the patients with primary thrombosis were much younger than those with recurrent thrombosis and their age did not exceed 50 years. According to the results obtained by us, it is possible to consider Leiden mutation, especially its homozygous form and double/triple heterozygous/homozygous carriage of the studied mutations as an independent risk factor of development of recurrent thrombosis in the Georgian population and prolong anticoagulation therapy in patients of similar genotype as much as possible to prevent recurrent thrombosis and related complications.