Factor V R506Q mutation-Leiden: an independent risk factor for venous thrombosis but not coronary artery disease

Incidence of Symptomatic Venous Thromboembolism in Patients with Hemophilia Undergoing Hip and Knee Joint Replacement without Chemoprophylaxis: A Retrospective Study

OBJECTIVE

To establish the prevalence of clinically significant venous thromboembolic events (VTE) in hemophilia patients undergoing total hip arthroplasty (THA) and total knee arthroplasty (TKA) without chemoprophylaxis and a modified coagulation factor substitution.

METHODS

A cohort of patients who underwent THA and TKA from June 2002 to April 2017 were included. Based on World Federation of Hemophilia (WFH) guidelines, a modified coagulation factor substitution regimen was adopted. All patients were under a standardized postoperative protocol with routine mechanical prophylaxis against VTE. None of the patients received prophylactic anticoagulation. Only symptomatic patients were referred for radiological examination to exclude VTE. We evaluated the patient demographics and calculated the prevalence of VTE in our cohort.

RESULTS

A total of 98 patients were reviewed. The patients were all men. Thirty-one patients underwent primary THA with 39 hip arthroplasties (only 1 case with hemophilia B) and 67 patients underwent primary TKA with 101 knee arthroplasties (5 cases with hemophilia B). The mean age was 34.2 ± 7.8 years. The mean body mass index was 21.2 ± 5.7 kg/m² . There was 100% compliance to mechanical prophylaxis. The mean time to ambulation was 6.8 days (±2.5 days), and the mean hospital stay was 32.4 days (±7.1 days). There was only 1 hemophilia B patient with clinically significant VTE. None of the other 97 surgical cases had symptomatic VTE within 6 months after the procedure. This translates to a prevalence of 1.02%.

CONCLUSION

Given the low incidence (1.02%) of clinically significant VTE in our cohort, routine chemoprophylaxis in hemophilia patients undergoing THA and TKA may not be needed.

The Prophylaxis of Venous Thromboembolism

BACKGROUND

Venous thromboembolism (VTE) is the third most common cardiovascular condition, after myocardial infarction and stroke. Prophylactic measures in accordance with current guidelines can significantly reduce the risk of VTE and the associated morbidity and mortality. Until now, the German interdisciplinary, evidence- and consensus-based (S3) clinical practice guideline on VTE prophylaxis was based on a complete review of all pertinent literature available in MEDLINE up to January 2008. More recent publications and drug approvals have made a thorough revision necessary.

METHODS

A systematic search was carried out in the MEDLINE and Embase databases for publications that appeared from 1 January 2008 to 7 August 2013. Updates of 5 national and international reference guidelines and 2 new Health Technology Assessment (HTA) reports were considered as well. A structured consensus-finding process was carried out with delegates from 27 scientific medical societies and from the Union of Medical Specialist Associations.

RESULTS

46 randomized controlled trials (RCTs) were included for critical appraisal. New findings led to re-evaluation of the value of compression stockings in combination with pharmacological prophylaxis (open recommendation), and suggest equal value of non-vitamin K antagonist oral anticoagulants (NOACs) and low molecular weight heparins (LMWH) or fondaparinux in elective hip and knee replacement (strong recommendation). For patients undergoing hip fracture surgery, we recommend LMWH or fondaparinux.

CONCLUSION

Further research is needed to assess the value of NOACs for pharmacological prophylaxis in orthopedic/trauma patients undergoing surgical procedures other than the ones mentioned above, and into the benefit and harm of new devices available for mechanical prophylaxis. The stringent implementation of basic measures such as early mobilization, movement exercises, and patient instruction is a key point to prevent venous thrombo - embolism.

Genetic Risk Factors of Venous Thromboembolism in the East Algerian Population

Many genetic risk factors have been identified for causing venous thromboembolism (VTE). Most of them affect the function of natural anticoagulant pathways, particularly the protein C system, although recent studies suggest a role of components of the hematopoietic pathway in the etiology of venous thrombosis. In this case–control study, we aimed to determine the frequency of prothrombin G20210A and factor V Leiden (FVL) G1691A polymorphisms and protein C, protein S, and antithrombin III deficiencies in the East Algerian population and to investigate whether these genetic factors are associated with VTE. On the other hand, our study tends to evaluate the status of JAK2V617F and calreticulin (CALR) mutations among these cases. The participants consisted of 121 cases with VTE and 146 healthy controls. Polymorphisms of FVL G1691A and prothrombin G20210A were genotyped by polymerase chain reaction (PCR) restriction fragment length polymorphism. JAK2-V617F and calreticulin mutations were analyzed by quantitative PCR and PCR followed by capillary electrophoresis sequencing, respectively. Protein C, protein S, and antithrombin levels were determined and then hereditary deficiencies were identified. Of all cases and controls, none was a carrier of the antithrombin III deficiency, prothrombin gene G20210A, and CALR mutations. Only 1 case reported having a positive JAK2 mutation (mutant allele burden was 15%). The FVL mutation (GA/AA) was found in 14 (11.6%) cases and 2 (1.4%) controls and it was significantly different between both the groups ( P = .001). Deficiencies of protein S and protein C were detected in 17 (18.8%) cases. The univariate analysis resulted in a significant impact of FVL (odds ratio [OR] = 9.4, 95% confidence interval [CI] = 2.1-42.3; P = .003) and of protein S deficiency (OR = 16.9, 95% CI =2.1-132.8, P = .007) on the VTE status. Both factors stayed significant after adjustment for sex and age. The OR of the protein C deficiency was slightly elevated (OR = 6.4, 95% CI = 0.7-55.5), but it did not reach the level of statistical significance ( P = .091), and it was therefore not considered as a risk factor. In conclusion, coagulant factor V gene G1691A mutation and protein S deficiency constitute important genetic risk factors in patients with VTE in Eastern Algeria. The somatic mutation of JAK2 V617F and CALR mutations are less frequent causes of VTE, thus routine testing for these mutations is not recommended.

Cohort study of Anticoagulation Self-Monitoring (CASM): a prospective study of its effectiveness in the community

BACKGROUND

Trials show that oral anticoagulation therapy (OAT) substantially reduces thromboembolic events without an increase in major haemorrhagic events, but it is not known whether these results translate into routine practice.

AIM

To estimate the current levels of control and adverse events in patients self-monitoring OAT, explore the factors that predict success, and determine whether the level of side effects reported from randomised controlled trials are translated to a non-selected population.

DESIGN AND SETTING

Prospective cohort study in the UK.

METHOD

Participants were aged ≥18 years and registered with a GP. Main outcomes were the proportion of participants, over 12 months, who were still self-monitoring, had not experienced adverse events, and had achieved >80% of time in therapeutic range (TTR).

RESULTS

In total, 296 participants were recruited; their median age was 61 years and 55.1% were male. Participants were predominately professional or held a university qualification (82.7%). At 12 months, 267 (90.2%) were still self-monitoring. Mean TTR was 75.3% (standard deviation 16.9).Six serious and two minor adverse events were reported by GPs. Only 45.9% of participants received any in-person training at the outset. Increased age (P = 0.027), general wellbeing (EQ-5D visual score, P = 0.020), and lower target international normalised range (INR, P = 0.032) were all associated with high (>80% TTR) levels of control.

CONCLUSION

The findings show that, even with little training, people on OAT can successfully self-monitor, and even self-manage, their INR. TTR was shown to improve with age. However, widespread use of self-monitoring of INR may be limited by the initial costs, as well as a lack of training and support at the outset.

High Incidence of ACE/PAI-1 in Association to a Spectrum of Other Polymorphic Cardiovascular Genes Involving PBMCs Proinflammatory Cytokines in Hypertensive Hypercholesterolemic Patients: Reversibility with a Combination of ACE Inhibitor and Statin

Cardiovascular diseases (CVDs) are significantly high in the Lebanese population with the two most predominant forms being atherosclerosis and venous thrombosis. The purpose of our study was to assess the association of a spectrum of CVD related genes and combined state of hypertension hypercholesterolemia (HH) in unrelated Lebanese. Twelve polymorphisms were studied by multiplex PCR and reverse hybridization of DNA from 171 healthy individuals and 144 HH subjects. Two genes were significantly associated with HH: ACE (OR: 9.20, P<0.0001) and PAI-1 (OR: 2.29, P = 0.007), respectively with the occurrence of the risky alleles “Del” and “4G”. The frequencies of the Del and 4G alleles were found to be 0.98 and 0.90 in the HH group versus 0.84 and 0.79 in the healthy group, respectively. Serum ACE activity and PAI-I increased significantly with Del/Del and 4G/5G genotypes. The co-expression of Del/4G(+/+) was detected in 113 out of 171 (66.0%) controls and 125 out of 144 (86.8%) HH subjects. Del/4G(-/-) was detected in only 6 (3.5%) controls and undetected in the HH group. Three venous thrombosis related genes [FV(Leiden), MTHFR(A1298C) and FXIII(V34L)] were significantly related to the prominence of the co-expression of Del/4G(+/+). A range of 2 to 8 combined polymorphisms co-expressed per subject where 5 mutations were the most detected. In Del/4G(+/+) subjects, peripheral blood mononuclear cells (PBMCs) produced significant elevated levels of IFN-γ and TNF-α contrary to IL-10, and no variations occurred for IL-4. ACE inhibitor (ramipril) in combination with statin (atorvastatin) and not alone reversed significantly the situation. This first report from Lebanon sheds light on an additional genetic predisposition of a complex spectrum of genes involved in CVD and suggests that the most requested gene FVL by physicians may not be sufficient to diagnose eventual future problems that can occur in the cardiovascular system. Subjects expressing the double mutations (Del/4G) are at high risk for the onset of CVDs.

Epidemiology of activated protein C resistance and factor v leiden mutation in the mediterranean region

Venous thromboembolic disorders (VTE) are serious disorders with high morbidity and mortality rates. Many genetic and acquired risk factors were identified to cause VTE. The most common genetic risk factor is Factor V Leiden mutation (FVL). FVL was found in high percentage of populations of Caucasian origin but was almost absent in non-Caucasians. It was also reported in populations living in North Africa and the Middle East. This review article briefly explains FVL and how it causes VTE, the distribution of FVL worldwide, and then it elaborates on the epidemiology of FVL in the Mediterranean Region and how this brought speculations that FVL might have originated in the Eastern Mediterranean area.

Risk stratification for venous thromboembolism in hospitalized patients in a developing country: a prospective study

Venous Thrombo-Embolism (VTE) is a serious complication in hospitalized patients but can be preventable. This prospective study addresses risk factors assessment and the use of heparin in this population. About 2,496 non pediatric patients were admitted to Jordan University Hospital between June 12, 2007 and July 19, 2007. A random sample of 624 patients consisting of every fourth admission was chosen. The stratification of risk factors was assessed using Caprini model and the ACCP score. The mean age of the patients (229 males and 395 females) was 45.34 +/- 18.3 years. More than 80% of the admitted patients were considered at high risk for VTE but heparin was used in only 26% of the patients. The majority of our patients constitute a high-risk population. Implementation of strategies including educational sessions and risk stratification guidelines can reduce the incidence, morbidity, and mortality of VTE especially in developing countries.

THROMBOPHILIC RISK FACTORS IN PATIENTS WITH CRANIAL AND SPINAL DURAL ARTERIOVENOUS FISTULAE

OBJECTIVE

Numerous studies have reported the technical aspects and results of surgical and/or endovascular treatment of cranial dural arteriovenous fistulae (cDAVF) and spinal dural arteriovenous fistulae (sDAVF). Only a few of them have addressed the question of thrombophilic conditions, which may be relevant as pathogenetic factors or can increase the risk for venous thromboembolic events. Therefore, the objective of this study is to compare thrombophilic risk factors in patients with cDAVF and sDAVF with no history of trauma.

METHODS

A total of 43 patients (25 with cDAVF and 18 with sDAVF) were included in this study. Blood samples were analyzed for G20210A mutation of the prothrombin gene and factor V Leiden mutation. In all patients, prothrombin time, international normalized ratio, fibrinogen, antithrombin, protein C and S activity, von Willebrand factor antigen, ristocetin cofactor activity, D-dimer, coagulation factor VIII activity, and tissue factor pathway inhibitor were determined. Screening was performed for the occurrence of lupus antiphospholipid and cardiolipin antibodies.

RESULTS

The prevalence of G20210A mutation of the prothrombin gene was significantly higher in patients with cDAVF (n = 6) compared with patients with sDAVF (n = 0; P &lt; 0.05, Fisher's exact test). A factor V Leiden mutation was found in 3 patients with sDAVF and in 1 patient with cDAVF (P = 0.29, Fisher's exact test). No significant difference was found for other parameters, except for fibrinogen, but decreased protein C activity was more frequent in patients with cDAVF compared with patients with sDAVF (4 versus 1). Decreased protein S activity was encountered in 3 patients (2 with sDAVF and 1 with cDAVF). Cardiolipin antibodies were found in 2 patients with cDAVF but in none with sDAVF, whereas only 1 patient with sDAVF had lupus antiphospholipid antibodies.

CONCLUSION

In both groups of patients with dural arteriovenous fistulae, genetic thrombophilic abnormalities occurred in a higher percentage than in the general population. The differences of the genetic abnormalities may be involved in different pathophysiological mechanism(s) in the development of these distinct neurovascular entities.

Gene polymorphisms in patients below 35 years of age who underwent coronary artery bypass surgery

OBJECTIVE

Genetic bases for novel prothrombotic, inflammatory risk factors may play a role in the early onset of coronary artery disease.

METHODS

Twenty-one patients below 35 years of age who underwent coronary bypass grafting between 2002 and 2004 constituted the study group and were compared with 50 healthy, age and sex-matched controls. Gene analysis for genetic polymorphisms of angiotensin-converting enzyme, prothrombin G20210A, tumour necrosis factor-alpha G308A, factor V Leiden and interleukin-6 genes was carried out.

RESULTS

The control group was 98% homozygous for the factor V Leiden GG allele and 2% heterozygous for the GA allele. On the other hand, the study group was 76.2% homozygous for the GG allele, and 23.8% heterozygous for the GA allele (P<0.05). Homozygosity for factor V Leiden mutation (AA) was not encountered in either group. With regard to interleukin-6, 70.0% of the control group demonstrated homozygosity for the GG allele and 30.0% showed heterozygosity (GC). The study group was 52.4% homozygous for the GG allele and heterogenicity was similar in this group (28.6% GC). On the other hand, 19.0% of this group demonstrated CC homogenicity (P<0.05). No difference was observed with regard to gene polymorphisms.

CONCLUSIONS

Gene polymorphisms with regard to prothrombotic factor V Leiden mutation and inflammatory marker interleukin-6 may play a role in the pathogenesis of early-onset coronary artery stenosis in patients below 35 years of age.

Comparison of the Prevalence of APC-resistance in Vascular Patients and in a Normal Population Cohort in Western Germany

OBJECTIVE

To compare the prevalence of APC-resistance (APC-R) in patients with peripheral vascular disease and the general population.

DESIGN

Prospective cohort examination.

MATERIALS AND METHODS

Three hundred and eleven patients (group A) suffering from arterial occlusive disease or an abdominal aortic aneurysm were prospectively screened for APC-R. There were 228 men and 83 women with a mean age of 65 years (20-88 years). Two hundred and sixty patients underwent an open surgical or interventional procedure. A total of 306 patients were followed clinically for an average of 8 months (1-31 months). Two hundred and seven healthy volunteers (group B) served as a control group.

RESULTS

The prevalence of a functional APC-R was 11% (33/311) and 8% in groups A and B, respectively, (p = 0.272). APC-R did not occur more frequently among patients who were treated primarily for a bypass occlusion (3/21 vs 30/290) (p = 0.476). None of five patients who had a postinterventional graft or vessel occlusion (1.9%) had an APC-R. Sixteen patients (5%) experienced an arterial occlusion during follow-up of which two had APC-R.

CONCLUSIONS

Previously published increased prevalence rates of APC-R in patients with arterial disorders could not be confirmed in this study. A firm association between the presence of APC-R and previous bypass occlusion or postoperative failure of the vascular reconstruction could not be demonstrated.

A new ELISA method to identify the D327N mutation of human sex hormone binding globulin (SHBG)

The D327N mutation of human SHBG is associated with a number of good prognostic factors in breast cancer like estrogen receptor positivity and erb2 negativity. The identification of this mutation, that requires only a small sample of circulating blood, could be helpful whenever tissue samples are too scanty for the determination of prognostic factors, e.g. at fine needle aspiration for cytology. The search for this mutation is routinely performed in our laboratory with the Hinfl restriction fragment length polymorphism (RFLP) technique on polymerase chain reaction (PCR)-amplified DNA. The present report describes a new and simple enzyme-linked immunosorbent assay (ELISA) method to detect the SHBG mutation. The DNA enzyme immuno assay (DEIA) method, that is widely used in virology and has already been used to identify single nucleotide mutations, allows the identification of hybrids between specific DNA sequences and biotynilated probes with a monoclonal antibody against double stranded-DNA. We here report that by using two specific probes, specifically built for this kind of test, one complementary to the wild type SHBG sequence and the other to the D327N mutated DNA, the DEIA technique can be used to identify on PCR-amplified DNA the D327N mutation of human SHBG exactly as the Hinfl RFLP technique. The DEIA technique could, thus, be especially helpful when a large number of samples has to be processed, the technique being easier than Hinfl RFLP, specific, reproducible and allowing substantial time saving.

Prothrombotic coagulation defects and cardiovascular risk factors in young women with acute myocardial infarction

We investigated the effect of prothrombotic coagulation defects in combination with smoking and other conventional risk factors on the risk of myocardial infarction in young women. In 217 women with a first myocardial infarction before the age of 50 years and 763 healthy control women from a population-based case-control study, factor V Leiden and prothrombin 20210A status were determined. Data on major cardiovascular risk factors and oral contraceptive use were combined with the presence or absence of these prothrombotic mutations, and compared between patients and controls. The overall odds ratio for myocardial infarction in the presence of a coagulation defect was 1.1 [95% confidence interval (CI) 0.6-1.9]. The combination of a prothrombotic mutation and current smoking increased the risk of myocardial infarction 12-fold (95% CI 5.7-27) compared with non-smokers without a coagulation defect. Among women who smoked cigarettes, factor V Leiden presence versus absence increased the risk of myocardial infarction by 2.0 (95% CI 0.9-4.6), and prothrombin 20210A presence versus absence had an odds ratio of 1.0 (95% CI 0.3-3.5). We conclude that factor V Leiden and prothrombin 20210A do not add substantially to the overall risk of myocardial infarction in young women. However, in women who smoke, the presence of factor V Leiden increased the risk of myocardial infarction twofold.