Venous Thromboembolism in Young Patients From Western India: A Study

Abstract

The goal of this article is to study the association of known markers of thrombophilia with venous thrombosis in young patients (< 45 years) from the Western part of India. A prospective study of 432 patients (252 males and 180 females, age 1-45 years) was conducted between 1994 and 2000 (6 years). The diagnosis was confirmed in all the patients by ultrasound with Doppler or by a computed tomograph (CT) scan of the brain with or without contrast depending on the case. Detailed clinical examination, and family history was taken to establish recurrent thrombosis and familial occurrence of thrombosis. The markers studied were protein C, protein S, antithrombin (AT) III, factor V Leiden mutation, prothrombin gene G20210A polymorphism, and the thermolabile MTHFR variant C677T polymorphism, using appropriate techniques. Lupus inhibitor was tested in the first 72 patients using Dilute Russel Viper Venom Time (DRVVT) test, and anticardiolipin antibodies were tested by enzyme-linked immunosorbent assay. Protein C, protein S, and AT III deficiency was detected in 9.5%, 6.5%, and 2.6%, respectively, among the patients. Anticardiolipin antibody was present in 9.9% of the patients, whereas lupus anticoagulant was present in 8.3% of patients; factor V Leiden mutation was detected in 3% of patients; thermolabile variant of MTHFR C677T polymorphism was present in 14.9% of patients with 1.2% homozygotes. Prothrombin G20210A polymorphism was not detected in any sample in this population. One hundred and four patients of 432 (24.9%) had recurrent attacks of thrombosis without any proximate precipitating cause, whereas 7.5 % of the patients had another close member of the family with a history of deep venous thrombosis. Eighty-six members from 28 families (out of 32 families giving family history of thrombosis) were investigated and found to have protein C and protein S deficiency in seven each; factor V Leiden was present in 6, and MTHFR C677T polymorphism was present in 5 cases. Hence, 25 of 86 members (28%) from the family of patients with familial history deep venous thrombosis had positive markers for thrombophilia. Thus, we could show that in young patients presenting with thrombosis, at least 34% of them had a demonstrable cause for thrombophilia. Prothrombin gene polymorphism G20210A seems to be nonexistent in our population and AT III deficiency also appears to be low compared to other markers of thrombophilia. There is a high prevalence of variant MTHFR C677T in our series, but the incidence of MTHFR C677T in our general population is also high. Hence, the significance of this finding in our cases of deep venous thrombosis remains to be seen, but we did not see any homozygotes when we tested 70 randomly selected asymptomatic persons, whereas in the present series, 1.8% of the patients had homozygosity for the MTHFR C677T polymorphism.