Evidence-based indications for thrombophilia screening

Management of Thrombosis in a Patient with Three Thrombophilic Disorders

Combined thrombophilia represents 7.8-8.3% of the patients with thrombophilia and confers a higher risk for thrombosis development and recurrence. Here, we present a 17-year-old boy carrier of three congenital thrombophilias, two severe (type I antithrombin deficiency and type I protein S deficiency) and one prothrombotic polymorphism (prothrombin G20210A), all in heterozygosis. He developed an extensive deep venous thrombosis in lower left limb, reaching proximal inferior vena cava and contralateral iliac vein, in the setting of prolonged rest. Endovascular therapy with local thrombolytic agent infusion followed by mechanical thrombectomy was performed, achieving a favorable clinical and radiological evolution. Antithrombin replacement to achieve levels between 80% and 120% with heparin administration was used during the endovascular procedure. The patient is currently asymptomatic and maintains indefinite anticoagulation with warfarin, keeping an appropriate anticoagulation range (international normalized range between 2.5 and 3.5).

[Deep vein thrombosis - diagnostics and clarification]

Deep vein thrombosis usually manifests as leg or pelvic vein thrombosis (DVT). The causes are either acquired or inherited and can also occur in combination. Early diagnosis and treatment of DVT can reduce the risk of pulmonary embolism and postthrombotic syndrome. The estimation of the clinical probability, if necessary in combination with the D-dimer test, points the way to further imaging diagnostics. After diagnosis, risk factors that led to the occurrence of thrombosis can be identified in many cases. In more than half of the cases, genetic causes play a role. If the cause is not clear, tumor screening should be performed, since up to 20 % of thromboses are due to tumor disease.

Serological Parameters and Vascular Investigation for a Better Assessment in DVT during Pregnancy-A Systematic Review

Pregnancy and the postpartum period represent a condition characterized by a thrombotic predisposition. The majority of pregnant women do not face acute or severe thrombotic events. In general, mild inconveniences such as leg swelling or moderately painful thrombotic events (phlebitis) are encountered. However, when pregnancy is associated with inherited or acquired deficits that affect homeostasis, the risk of acute or even life-threatening events can increase significantly. The major consequence is the loss of the fetus or the venous thromboembolism that endangers the mother's life. Venous thromboembolism is caused by deep vein thrombosis, therefore timely detection and especially the assessment of the extent of the thrombotic event are crucial. In this paper we have summarized the most important paraclinical investigations. The study emphasizes the importance of selecting the methods of investigation. The right choice allows establishing a correct diagnosis and individualizing the treatment.

Phlegmasia cerulea dolens - an uncommon but alarming manifestation of deep vein thrombosis

In phlegmasia cerulea dolens (PCD), immediate diagnosis and prompt treatment is crucial for limb salvage. Aggressive treatment options including venous intervention, thrombolysis and/or surgical thrombectomy should be considered. Due to the lack of data, the most appropriate intervention depends upon etiology of PCD, clinical presentation and patient's bleeding risk.

Diagnosis of hypothenar hammer syndrome in a patient with acute ulnar artery occlusion

A 56-year-old truck driver with a history of tobacco use presented with acute onset digital ischaemia in the ulnar distribution of his dominant hand, associated with severe pain. Occupational exposures included extensive manual labour and prolonged vibratory stimuli. Workup with Doppler and angiography confirmed the diagnosis of hypothenar hammer syndrome (HHS). After the failure of medical management, he underwent ulnar artery thrombectomy with reconstruction and arterial bypass grafting. His pain improved significantly postsurgically, and he was able to return to a normal routine. This case illustrates the classic presentation, examination, imaging findings and management options of HHS. HHS should be considered in patients with digital ischaemia and associated occupational exposures. Diagnosing the condition appropriately allows for optimal management, aiming at minimising symptoms and maximising quality of life.

Thrombophilia Screening: Universal, Selected, or Neither?

The utility of thrombophilia testing in clinical practice is still a matter of debate because studies have not shown a benefit in the reduction of recurrent venous thromboembolism (VTE) risk in patients with thrombosis, despite the clearly higher VTE risk for first thrombosis. Screening for thrombophilia is indicated in selected patients. Particularly in selected young patients, especially women of childbearing age, the knowledge of the genetic thrombophilic defect may help in specific situations to decrease the risk of VTE events. Avoidance of modifiable risk factors and/or prophylactic thromboembolic procedures may be evaluated in selected patients. A comprehensive workup including personal and familial history, clinical examination, and laboratory test results including hereditary thrombophilia remains helpful in assessing the cumulative risk and the management of this group of selected patients.

Guidance for the evaluation and treatment of hereditary and acquired thrombophilia

Thrombophilias are hereditary and/or acquired conditions that predispose patients to thrombosis. Testing for thrombophilia is commonly performed in patients with venous thrombosis and their relatives; however such testing usually does not provide information that impacts management and may result in harm. This manuscript, initiated by the Anticoagulation Forum, provides clinical guidance for thrombophilia testing in five clinical situations: following 1) provoked venous thromboembolism, 2) unprovoked venous thromboembolism; 3) in relatives of patients with thrombosis, 4) in female relatives of patients with thrombosis considering estrogen use; and 5) in female relatives of patients with thrombosis who are considering pregnancy. Additionally, guidance is provided regarding the timing of thrombophilia testing. The role of thrombophilia testing in arterial thrombosis and for evaluation of recurrent pregnancy loss is not addressed. Statements are based on existing guidelines and consensus expert opinion where guidelines are lacking. We recommend that thrombophilia testing not be performed in most situations. When performed, it should be used in a highly selective manner, and only in circumstances where the information obtained will influence a decision important to the patient, and outweigh the potential risks of testing. Testing should not be performed during acute thrombosis or during the initial (3-month) period of anticoagulation.

Endothelial Nitric Oxide Synthase T-786C Mutation, Prothrombin Gene Mutation (G-20210-A) and Protein S Deficiency Could Lead to Myocardial Infarction in a Very Young Male Adult

INTRODUCTION:

Myocardial infarction is a rare medical event in young people. The main reasons include congenital coronary abnormalities, coronary artery spasm, and coronary thrombosis due to hypercoagulable states (hereditary and acquired).

AIM:

We present a case of a young male adult with myocardial infarction caused by a combination of gene mutations and anticoagulation protein deficiency.

CASE PRESENTATION:

A 19 years old young man was admitted to our hospital complaining of chest pain during the last two weeks. The patient did not have any known cardiovascular risk factors, except a positive family anamnesis. Subacute inferior nonST segment myocardial infarction was diagnosed according to the patient’s history, electrocardiographic and laboratory findings. Coronary angiography revealed suboclusive thrombus in the proximal, medial and distal part of the right coronary artery (TIMI 2). Percutaneous coronary intervention was performed. Anticoagulant and antiagregant therapy (heparin, acetilsalicilic acid and clopidogrel) according to protocol was started. The hospital stay was uneventful. Homozygous endothelial nitric oxid synthase (eNOS) T-786-C mutation, heterozygote prothrombin gene mutation (G-20210-A), and protein S deficiency were verified from the thrombophilia testing. Other trombophilic tests were normal. Three months after discharge from hospital another coronary angiography was performed. It revealed normal coronary arteries. Four years after the attack, the patient is free of symptoms and another cardiovascular event.

CONCLUSION:

Combination of genetic mutations and anticoagulation protein deficiency could be a reasonable cause for myocardial infarction in a very young male adult without any other cardiovascular risk factors.

Phlegmasia cerulea dolens in a teenage boy found to have Factor V Leiden

A 16-year-old boy with morbid obesity and asthma presented with 1 week of progressive right leg pain, swelling and discolouration that started 1 week after a minor fall. Ultrasound and then CT with contrast revealed a large occlusive deep venous thrombosis (DVT) extending from the calf through the inferior vena cava bifurcation. Heparin was initiated and catheter-directed thrombolysis with tissue plasminogen activator and balloon angioplasty were performed with good flow postprocedure, however, the clot reaccumulated after several days and the procedure had to be repeated. After this occurred twice more, finally a right common iliac and femoral vein stent was placed to prevent clot reaccumulation and vein stenosis. Hypercoagability testing revealed activated protein C resistance and genetic testing confirmed homozygous Factor V Leiden (FVL). Family history was significant for maternal lower extremity DVT at age 21 and possible DVT in the patient's maternal grandmother.

Inherited Thrombophilia

Thrombophilia alters normal hemostasis, shifting the balance in favor of thrombus formation. Inherited conditions include factor V Leiden (FVL), prothrombin G20210A mutation, deficiencies in natural anticoagulants (antithrombin [AT], protein C, and protein S), hyperhomocysteinemia, and elevations in clotting factors (factors VIII and XI). Although FVL and prothrombin mutation are common disorders, deficiencies in the natural anticoagulants are rare. The risk of initial thrombosis conferred by inherited thrombophilia varies with the highest risk in those homozygous for either FVL or prothrombin mutation, or with AT deficiency. In the nonpregnant patient, the presence of a thrombophilia does not affect treatment of an acute event. Although vitamin B supplementation has been shown to decrease the levels of homocysteine, the treatment has failed to show a benefit in thrombus prevention and is therefore not recommended.

Prevalence of thrombophilia according to age at the first manifestation of venous thromboembolism: results from the MAISTHRO registry

Thrombophilia is a well-established risk factor for a venous thromboembolic event (VTE), and it has been proposed that hereditary thrombophilia may substantially contribute to the development of VTE in young patients. We aimed to analyse the prevalence of thrombophilia with special regard to the age of VTE manifestation. The study cohort consisted of 1490 patients (58% females) with a median age 43 years at the time of their first VTE. At least one thrombophilic disorder was identified in 50·1% of patients. The probability of detecting a hereditary thrombophilia declined significantly with advancing age (from 49·3% in patients aged 20 years and younger to 21·9% in patients over the age of 70 years; P < 0·001). This may be primarily attributed to the decreasing frequencies of the F5 R506Q (factor V Leiden) mutation and deficiencies of protein C or protein S with older age at the time of the initial VTE event. Moreover, thrombophilia was more prevalent in unprovoked compared with risk-associated VTE (57·7% vs. 47·7%; P = 0·001). The decline in the prevalence of hereditary thrombophilia with older ages supports the use of a selected thrombophilia screening strategy dependent on age and the presence or absence of additional VTE risk factors.

Association between Thrombophilia and the Post-Thrombotic Syndrome

The post thrombotic syndrome (PTS) is a chronic condition that develops in 20%–40% of deep vein thrombosis (DVT) patients. While risk factors that predispose to the development of venous thromboembolism (VTE) are widely known, factors that influence the development of PTS after DVT have not been well elucidated. Over 10% of the general population is affected by one or more identifiable inherited thrombophilias which have been shown to underlie at least 1/3 of cases of VTE. The various thrombophilias are important risk factors for VTE, but it is unknown whether they also increase the risk for development of PTS. We performed a review of studies that have reported on the association between thrombophilia and the development of PTS in populations of patients with DVT and with chronic venous ulcers. Studies vary with regards to the definition of PTS, study design, follow-up period, and present conflicting results. Based on these results, the question of whether thrombophilia predisposes to the development of PTS remains unanswered.

Vascular graft thrombosis secondary to activated protein C resistance: a case report and literature review

Hypercoagulability is a well-documented and prominent risk factor for venous thromboembolism. The role of thrombophilia in arterial thrombotic events is less well defined. A 52-year-old male patient with multiple atherogenic risk factors was admitted for non-healing pedal ulcer and absent distal pulses. Based on the clinical presentation, Doppler ultrasound and angiography findings, the patient underwent elective in situ bypass arterial reconstruction. The saphenous vein graft was of satisfactory quality and the procedure went routinely. Acute graft thrombosis on postoperative day 0 was recognized immediately and prompted an emergent surgical revision. No technical errors or anatomical/mechanical causes for failed reconstruction were found and the graft was successfully thrombectomized using a Fogarty balloon-catheter. Graft rethrombosis, however, ensued after several hours. Considering the absence of threatening limb ischemia and the idiopathic recurrent thrombosis, raising suspicion of prothrombotic state, conservative treatment was pursued. Postoperative thrombophilia testing proved positive for activated protein C resistance, mandating introduction of chronic oral anticoagulation. Six months later, the operated extremity is viable. Inexplicable vascular graft thrombosis, particularly if early and recurrent, should raise suspicion of underlying thrombophilia. If confirmed by laboratory testing, long-term secondary antithrombotic prophylaxis may be required.

To be or not to be: the patient's view of thrombophilia testing

INTRODUCTION

The literature on the psychological effects of thrombophilia testing is unclear. Little is known about the complex world of significance subjects construct around the test.

OBJECTIVE

The study explored the peculiar network of implicit meanings that may be linked to the experience of being tested.

MATERIALS AND METHODS

The research was designed according to Interpretative Phenomenological Analysis (IPA). 19 patients were interviewed. Integral verbatim reports of the interviews were analyzed through an inductive process aimed at gaining a holistic understanding of the narratives.

RESULTS

Two main issues were identified, each with sub-issues: (1) the clinical problem: (1.1) unhealthy blood and (1.2) the family issue; (2) the test: (2.1) knowing for the sake of knowing; (2.2) knowing for the sake of doing; (2.3) not knowing.

CONCLUSIONS

The thrombophilia test is part of a larger network of meanings, where information about the test and its results seem to be lost.

PRACTICE IMPLICATION

The study suggests the importance of paying greater attention to the process of doctor-patient communication at the time of the test. The theme of being informed is important for patients, yet often they are not able to understand or retain the information they receive, increasing the risk of misunderstandings.

Whole blood gene expression analyses in patients with single versus recurrent venous thromboembolism

INTRODUCTION

Venous thromboembolism may recur in up to 30% of patients with a spontaneous venous thromboembolism after a standard course of anticoagulation. Identification of patients at risk for recurrent venous thromboembolism would facilitate decisions concerning the duration of anticoagulant therapy.

OBJECTIVES

In this exploratory study, we investigated whether whole blood gene expression data could distinguish subjects with single venous thromboembolism from subjects with recurrent venous thromboembolism.

METHODS

40 adults with venous thromboembolism (23 with single event and 17 with recurrent events) on warfarin were recruited. Individuals with antiphospholipid syndrome or cancer were excluded. Plasma and serum samples were collected for biomarker testing, and PAXgene tubes were used to collect whole blood RNA samples.

RESULTS

D-dimer levels were significantly higher in patients with recurrent venous thromboembolism, but P-selectin and thrombin-antithrombin complex levels were similar in the two groups. Comparison of gene expression data from the two groups provided us with a 50 gene probe model that distinguished these two groups with good receiver operating curve characteristics (AUC 0.75). This model includes genes involved in mRNA splicing and platelet aggregation. Pathway analysis between subjects with single and recurrent venous thromboembolism revealed that the Akt pathway was up-regulated in the recurrent venous thromboembolism group compared to the single venous thromboembolism group.

CONCLUSIONS

In this exploratory study, gene expression profiles of whole blood appear to be a useful strategy to distinguish subjects with single venous thromboembolism from those with recurrent venous thromboembolism. Prospective studies with additional patients are needed to validate these results.

Fertility, Infertility and Thrombophilia

Hypercoagulation has been reported in some studies to be associated with reproductive failures, such as unexplained infertility, IVF implantation failure and recurrent fetal losses. Many pregnancy-related disorders have been interpreted as consequences of impaired microvascular function and might be viewed as a mild form of venous thromboembolic disease. In the absence of clinical guidelines, there is a need for an evidence base regarding thrombophilic screening and antithrombotic therapy in cases of reproductive failure. This article will focus on the controversial effect of congenital and acquired thrombophilia on human fertility, and will review the English literature for relevant studies identified by searching PubMed® results between January 1966–November 2010 using the key words: ‘thrombophilia‘, ‘fertility’ and ‘infertility‘.

A large and massive abdominal venous thrombosis associated with the presence of a big axillary mass, lupus-like syndrome and antiphospholipid antibodies

This case report concerns a 40-year-old patient with an unspecific abdominal pain, diarrhoea, a big axillary mass and a previous pulmonary infection. After biopsy of the axillary mass the diagnosis of lymphoma was excluded based on the presence of cells expressing polyclonal antibodies. Abdominal CT scans and angionuclear magnetic resonance showed an extensive intestinal venous thrombosis. The patient also presented positive results for C and S proteins, lupic anticoagulant factor and antiphospholipid antibodies (anticardiolipin antibodies - IgM and IgG). Treatment started with administration of recombinant tissue plasminogen activator and heparin which decreased the degree of thrombosis. Antibiotics were also administrated to treat pulmonary and abdominal infections. After 25 days, he was discharged with no signs of infection, no abdominal pain and reduction of the thrombosis. He was medicated with warfarin, hydroxichloroquine and clopidogrel. Forty-five days after discharge, abdominal CT scan showed a significant regression of thrombosis.

Thrombophilia in patients with chronic venous leg ulcers-a study on patients with or without post-thrombotic syndrome

BACKGROUND

Chronic venous leg ulcers (CVU) cause considerable burden of disease for the patients as well as enormous costs for health care systems. The pathophysiology of CVU is complex and not entirely understood. So far reliable pathogenic and/or prognostic parameters have not been identified.

OBJECTIVES

We studied the role of thrombophilia in patients referred to a University dermatology department for treatment of CVU.

PATIENTS AND METHODS

A cohort of 310 patients with active chronic venous leg ulcers (CEAP 6) was stratified into two comparably large groups according to the presence or absence of post-thrombotic syndrome (PTS+; PTS-) as determined using duplex scan and/or phlebography. In addition, several thrombophilia parameters were assessed.

RESULTS

The prevalence of protein S deficiency and factor V Leiden mutation was significantly higher in PTS+ patients compared with the PTS- group. However, patients in both subgroups revealed high prevalences of thrombophilia (antithrombin deficiency, protein C deficiency, protein S deficiency, activated protein C resistance, factor V mutation or elevated homocysteine).

CONCLUSION

Based on these data, it is conceivable that thrombophilia contributes to the pathogenesis of CVU, possibly through induction of microcirculatory dysregulations.

Diagnostic algorithm for thrombophilia screening

Thrombophilia screening is aimed at detecting the most frequent and well-defined causes of venous thrombosis, such as activated protein C resistance/factor V Leiden mutation, prothrombin G20210A gene mutation, deficiencies of natural anticoagulants, such as antithrombin, protein C and protein S, the presence of antiphospholipid antibodies, hyperhomocysteinemia and increased factor VIII activity. At this time, thrombophilia screening is not recommended for those possible congenital or acquired risk factors, whose association with increased risk of thrombosis has not been proven sufficiently. Laboratory investigations should include a step-wise approach to the diagnosis of thrombotic disorders with respect to the assays and methods of analysis that are used. The assays recommended for the first diagnostic step of screening should establish, whether the subject has one of the common causes of thrombophilia. If one or more abnormal results are obtained, the second diagnostic step includes the assays recommended for confirmation and/or characterization of the defect. When performing the investigation of thrombophilia, it is important to consider all pre-analytical and other variables that may affect the results of thrombophilia testing, including time of testing, age, gender, liver function, hormonal status, pregnancy or the acute phase response to inflammatory diseases. This is necessary, in order to avoid, any misinterpretation of the results. This review summarizes the current knowledge concerning thrombophilia investigations, with special focus on the diagnostic algorithm regarding patient selection, the assays and methods of analysis used and all the variables that should be considered when employing tests for the diagnosis of thrombophilia.

Thrombophilia screening--at the right time, for the right patient, with a good reason

Thrombophilia can be identified in about half of all patients presenting with venous thromboembolism (VTE). Thrombophilia screening for various indications has increased tremendously, but whether the results of such tests help in the clinical management of patients is uncertain. Here, current recommendations for thrombophilia screening in selected groups of patients, and considerations whether other high-risk subjects should be tested are reviewed. The methods for determination of the most common thrombophilic defects (antithrombin, protein C, protein S deficiencies, Factor V Leiden and prothrombin G20210A) associated with strong to moderate risk of VTE are described, indicating the timing and location of thrombophilia screening. Circumstances when a positive result of thrombophilia screening helps clinicians decide if adjustments of the anticoagulant regime are needed are discussed. Finally, psychological, social and ethical dilemmas associated with thrombophilia screening are indicated.

Migrating venous thrombosis in acute leukemia

We present a 55-year-old man with acute migrating thrombophlebitis and deep vein thrombosis of muscle veins in both calves indicating occurrence of acute myelomonocytic leukemia. Thrombosis of superficial and deep veins of the lower limbs arose in spite of the adequate anticoagulation therapy with warfarin.

Idiopathic (unexplained) pulmonary embolism is associated with an impaired prognosis compared to other entities of pulmonary embolism

In patients following acute pulmonary embolism, little is known about long-term prognosis attributed to individual risk factors and entities of pulmonary embolism. The aim of our study was to identify predictors of long-term mortality and morbidity, taking into account precipitating causes and entities of pulmonary embolism, especially in cases of idiopathic pulmonary embolism. We reviewed the records of 257 consecutive patients presenting with acute pulmonary embolism in the emergency room of the University Hospital in Frankfurt between 1997 and 2006. The median of the follow-up time in this study population was 670 days (n = 236; interquartile range: 378-1397 days). The patients were divided into three groups depending on the cause of pulmonary embolism: idiopathic pulmonary embolism (n = 83; 33%), neoplasm (n = 44; 17%) and other causes (n = 130; 50%). As expected, patients with neoplastic-associated pulmonary embolism demonstrated the poorest prognosis in the Kaplan-Meier analysis. Surprisingly though, patients with idiopathic pulmonary embolism demonstrated a markedly worse long-term survival compared with other causes (log-rank P < 0.001). When Cox-regression analysis was restricted to patients discharged alive without neoplasm, idiopathic pulmonary embolism was the strongest predictor of long-term mortality (hazard ratio: 3.29; P = 0.017). Patients with acute pulmonary embolism and known malignancy demonstrated the highest mortality compared with those with other causes. However, idiopathic pulmonary embolism is a common diagnosis and is associated with an unfavorable long-term prognosis compared with other entities of pulmonary embolism.

Thrombosis in the pediatric population

Whereas thrombotic events in critically ill children do not occur as commonly as in adults, they are being recognized with increasing frequency in the pediatric intensive care unit. The reasons for this are not clear but likely include an increased awareness of the problem and the ability to make a diagnosis using relatively noninvasive tests. In this section, I attempt to define the extent of the problem, summarize and discuss the relevant literature (pointing out where published experience in the pediatric population differs from that in adult patients), and suggest some guidelines regarding thrombophilia treatment and the management of thrombotic events.

Evidence-based medicine and practice guidelines: application to genetics

The Professional Practice and Guidelines Committee of the American College of Medical Genetics has the responsibility of overseeing the development of guidelines for the practice of clinical genetics. In the past, most, if not all, guidelines were primarily based on expert opinion. However, recently the goal has become to develop guidelines that are more evidence-based, or at least, to recognize the level of evidence available to the authors of these documents. This article reviews the challenges that are faced by geneticists who are charged with the development of practice guidelines.