Heterogeneous distribution of factor V Leiden in patients from north India with venous thromboembolism

ABO Blood Groups and Thrombophilia Markers in Patients With Unstimulated Thrombosis in Kurdistan Region of Iraq

Thromboembolism (TE) is a complex disease caused by various acquired and inherited factors. The common mutations; factor V Leiden G1691A (FVL G1691A), prothrombin G20210A (PTG20210A), and methylene tetrahydrofolate reductase C677T (MTHFR C677T) are important inherited causes in both venous and arterial thrombosis. The association between ABO blood groups and thrombophilia has been noted by researchers. We aimed to determine the frequency and association of ABO blood groups as a risk factor along with 3 thrombophilia mutations and another 3 thrombophilia markers in a group of patients with unstimulated thrombosis. In a prospective case-control study, we focused on 100 samples, 50 patients with documented thrombosis as well as 50 healthy age-matched controls. Multiplex polymerase chain reaction and reverse hybridization to oligonucleotide particular probes were employed to detect FVL G1691A, PT G20210A, and MTHFR C677T mutations. Analysis of other thrombophilia markers including protein C (PC), protein S (PS), and antithrombin (AT) assays was also performed. ABO blood group typing was done according to standard methods. Non-O blood group was significantly more frequent among cases than controls (76% vs 54%) with high odds of TE (odds ratio [OR] = 2.69). Positivity for at least 1 thrombophilia marker was more in cases (60%) than controls (34%; OR = 2.9). The combined effect of non-O blood group and thrombophilia markers raised the risk of TE (OR = 4.16, P = .001), particularly FVL (OR = 6.76). This study illustrates that harboring the non-O blood group poses an additive effect with other thrombophilia markers in the causation of TE.

Marburg I Polymorphism (G511E) in Adults with Deep Vein Thrombosis

The Marburg I polymorphism (G511E) in FSAP gene was listed as one of the risk factor for idiopathic DVT among the western population. The frequency of Marburg I polymorphism in India is presently not known. Fifty DVT cases and 50 healthy controls were tested for Marburg I polymorphism using ARMS-PCR technique. The thrombophilic risk factors (Protein C, Protein S, Antithrombin III, Factor V Leiden and antiphospholipid antibodies) were also determined. Marburg I polymorphism (heterozygous) was found in 2 patients (4%) but not in control subjects. These two cases did not have any other thrombophilia markers. Among the thrombophilic markers, heterozygous FVL mutation, PS, PC, AT deficiencies and antiphospholipid antibodies were seen in 10%, 10%, 6%, 6% and 8% of the patients respectively. The controls showed only the presence of antiphospholipid antibodies in 6% of subjects. Marburg I polymorphism among Indians DVT patients was determined for the first time. Its incidence was found in 4% of cases and not in controls. Although not statically significant this may be considered as one of the contributory risk factors for the development of DVT. A larger study is required for the validation of data.

Inherited thrombophilia in unprovoked venous thromboembolism: Is non 'O' blood group an additional culprit in Indian patients?

BACKGROUND

Venous thromboembolism (VTE) is a known situation of considerable mortality and morbidity and occurs due to the convergence of multiple acquired and genetic risk factors.

METHODS

In this study, we have comprehensively analyzed the effect of ABO blood groups and inherited thrombophilia factors [Protein C (PC), Protein S (PS), Antithrombin III (AT III), Activated Protein C Resistance (APCR) and Homocysteine (Hcy)] on 150 unprovoked VTE patients, comparing with normal healthy controls. ABO phenotyping was done using gel cards and thrombophilia workup done using standard kits on coagulation autoanalyzer.

RESULTS

Non O blood group was significantly more frequent among cases than controls (77.3% vs. 62.7%) and had higher odds of VTE (OR = 2.03, 95%CI: 1.22-3.37).Positivity for at least one marker of thrombophilia was more in cases (40%) than controls (16%), and led to significantly higher odds (OR = 3.5, 95%CI: 2.03-6.04) of VTE. Deficiency of PS was the commonest thrombophilia abnormality.Combination of non O group with positivity for thrombophilia markers was also more among cases (OR = 5.67, 95%CI: 2.76-11.65). Highest odds of VTE in cases were associated with non O group in combination with increased Homocystein (OR = 10.8, 95%CI: 2.27-51.5).

CONCLUSION

The study results show non O blood group and positivity for factors of inherited thrombophilia in cases impart higher odds of VTE individually. Also combination of both non O blood group and positivity for factors of inherited thrombophilia in cases further increases the odds of VTE. This awareness could assist physicians in identifying those at higher risk of VTE and tailor-made the thromboprophylaxis accordingly.

High prevalence of factor V Leiden and prothrombin G20101A mutations in Kashmiri patients with venous thromboembolism

AIM

The genetic variants of the factor V (G1691A), prothrombin (G20210A) and MTHFR (C677T) genes have been widely implicated as inherited risk factors for developing venous thrombosis. This study was undertaken to reveal the frequency of these mutations in Kashmiri patients with venous thromboembolism.

METHODOLOGY

A case-control study was designed with 250 VTE patients and 250 healthy controls. The mutations were analysed using ARMS-PCR and PCR-RFLP approach.

RESULT

The factor V Leiden G1691A mutation was found in 17/250 (6.8%) VTE patients and prothrombin G20210A mutation was found in 7/250 (2.8%) VTE patients while no mutation was found in any of the healthy controls. Both the mutations were found to be significantly associated with the increased risk of VTE (p = 0.0001 and 0.0150 respectively) while no association of VTE risk with MTHFR C677T polymorphism was found (p = 0.53).

CONCLUSION

The increased frequency of factor V Leiden G1691A and prothrombin G20210A mutation in VTE patients indicates a significant role of these mutations in the development of VTE in our population. We therefore suggest the routine screening of these two mutations as thrombophilic markers in Kashmiri patients with venous thromboembolism.

To determine the frequency of Factor V Leiden in cases of Deep Vein Thrombosis and Healthy controls

Objective:

To determine the frequency of Factor V Leiden in cases of Deep Vein Thrombosis and Healthy controls.

Methods:

This case control study was performed in Armed Forces Institute of Pathology Rawalpindi, From 21^st March to 25^th September 2013. One hundred patients with diagnostic evidence of Deep vein thrombosis on Doppler ultrasound/Magnetic resonance imaging (MRI) scan were included in the study through non probability convenient sampling and compared with 100 matched healthy controls. DNA was extracted from the blood sample by kit method. In order to identify Factor V Leiden mutation, the polymerase chain reaction (PCR) method was utilized combined with the Amplification refractory mutation system. Data was analyzed using statistical package for social sciences (SPSS) version 17.

Results:

In 100 patients of Deep Vein Thrombosis (DVT), frequency of Factor V Leiden (FVL) was 13% and it is was 2% in healthy control group. A significant association was found between FVL and DVT with odds ratio of 7.32 and with P value (P = 0.003).

Conclusion:

FVL was found to be highly prevalent among patients of DVT, Signifying strong association between the two.

Venous thromboembolism and ethnicity

Venous thromboembolism (VTE) has long been considered a disease that affects predominantly white populations, a misconception resulting from a paucity of epidemiological data from non-Western countries, and the low incidence of hereditary thrombophilia in those of non-Caucasian background. Over the last decade, interest has grown in this area with the emergence of evidence that VTE is as prevalent, if not more so, in the black population and is also common in Asian groups. Much is still to be learned, as our current knowledge of hereditary thrombophilia and acquired risk factors do not fully explain the risk of VTE in non-Caucasian groups. This review summarises the current understanding of ethnic variation in VTE and highlights the need for further research in this area.

Thrombophilic gene polymorphisms in puerperal cerebral veno-sinus thrombosis

Puerperal cerebral veno-sinus thrombosis (PCVT) is a common form of stroke in young women in India, which is associated with high morbidity and mortality. The frequency of PCVT in India is 10 to 12 times more compared to western population. As yet, the etiology of this condition is unclear. Our aim was to study the prevalence and the role of the common genetic polymorphisms associated with thrombophilia such as factor V Leiden, prothrombin G20210A and methylene tetrahydrofolate reductase (MTHFR) C677T, in aseptic PCVT. We investigated 86 women with PCVT and 86 age-matched women with no post-partum complications. Polymerase chain reaction (PCR)/restriction fragment length polymorphism analysis was used to identify their genotypes. The frequency of the three polymorphisms in cases and controls were: factor V Leiden, 2.3% versus 1.2% (OR 0.49, 95% CI=0.02-7.12, p=1.000) and MTHFR C677T, 16.3% versus 17.4% (OR 0.92, 95% CI=0.39-2.19, p=0.838). The prothrombin G20210A variant was not detected in either patients or controls. The clinical characteristics of the PCVT patients with the polymorphisms did not differ significantly from those without them. In our series of PCVT patients, the risk associated with the established thrombophilic risk factors is insignificant. Exploration of these gene polymorphisms seems to be of limited value in the investigation of PCVT in south Indian women.