Patients with antiphospholipid antibodies and venous thrombosis should receive long term anticoagulant treatment

Global Antiphospholipid Syndrome Score (GAPSS) in patients with primary antiphospholipid syndrome

Stratification of patients into groups of high and low risk of adverse outcome is necessary for timely and early prevention of the disease, as well as the selection of adequate therapy.Objective: to validate the global risk scale for the development of clinical manifestations of antiphospholipid syndrome (GAPSS) in a cohort of patients with primary antiphospholipid syndrome (PAPS).Material and methods. The study included 64 patients with PAPS. Data on clinical manifestations, traditional cardiovascular risk factors, and antiphospholipid antibody profile were collected. GAPSS values were calculated for each patient by summing the scores corresponding to risk factors as follows: 3 points – for hyperlipidemia; 1 point – for arterial hypertension; 5 points – for antibodies to cardiolipin (aCL) IgG/IgM; 4 points – for antibodies to â2-glycoprotein 1 (anti-â2GP1) IgG/IgM and 3 points – for antibodies to the phosphatidylserine-prothrombin complex (aPS/PT) IgG/IgM.Results and discussion. GAPSS indicators were comparable in women and men with PAPS – 12.0 [9.0; 13.0] points. GAPSS values did not differ in patients with thrombosis and obstetric pathology: in thrombosis they were 10.0±4.46 (range 0.0–14.0) points, in obstetric pathology – 9.26±5.08 (range 0.0–14.0) points.The localization of thrombosis did not affect the GAPSS values, which reached 9.23±5.21 points in arterial thrombosis, 10.44±4.01 points in venous thrombosis, and 10.33±4.18 points in combined ones. Patients with recurrent thrombosis had higher GAPSS scores compared to patients without relapse: 8.19±5.25 points versus 11.00±3.65 points (p=0.01). There were no significant differences in GAPSS scores in obstetric pathology at different gestational ages.GAPSS values ≥6 showed a higher risk of thrombosis recurrence: odds ratio 5.23 (95% CI 1.34–20.37). GAPSS scores ≥6 demonstrated the highest accuracy, with sensitivity and specificity of 72% and 66%, respectively. According to ROC analysis, the AUC value for GAPSS was 0.675 (95% CI 0.542–0.808; p=0.01).Conclusion. The use of GAPSS makes it possible to identify patients at increased risk of recurrent thrombosis. GAPSS scores ≥6 have high sensitivity (72%) and specificity (66%), which can be used to stratify patients with PAPS into high and low risk groups for recurrent thrombosis.

Pregnancy termination in patients with rheumatic diseases

Rheumatic diseases affect women during their reproductive years. Many women with rheumatic diseases become pregnant; some undergo pregnancy termination. However, there are no official guidelines on pregnancy termination in patients with rheumatic diseases. This paper provides an overview of considerations that healthcare professionals must take into account. We highlight areas that require further studies and the importance of pregnancy planning and contraception counseling. Patients with rheumatic diseases need to be informed of adverse maternal and fetal outcomes of pregnancy to make informed reproductive decisions and reduce the need for pregnancy terminations. This article is protected by copyright. All rights reserved.

Loss of antiphospholipid antibody positivity post-thrombosis in SLE

Background/Purpose

Loss of positivity of antiphospholipid antibodies has been observed in clinical practice post-thrombosis in patients with SLE with secondary antiphospholipid syndrome (APS). Our study defined the frequency of this loss and the duration before positivity recurred.

Methods

In this prospective study, patients with SLE having at least two positive antiphospholipid markers prior to thrombosis and at least 1 year of follow-up after thrombosis were included. Antiphospholipid markers included lupus anticoagulant (dilute Russell viper venom test >45 s followed by mixing and confirmatory tests) and/or anticardiolipin titre (aCL IgG ≥20, aCL IgM ≥20 and/or aCL IgA ≥20). The percentage of visits with positive antiphospholipid markers after thrombosis was calculated. For patients with a negative antiphospholipid marker any time after thrombosis, survival estimates were performed to calculate the time to return of antiphospholipid positivity.

Results

In APS due to SLE, complete loss of antiphospholipid positivity post-thrombosis was up to 41% for aCL IgG, 51% for IgM and 50% for IgA, but only 20% for those with lupus anticoagulant. Of those who at some point lost aCL IgG or became negative for lupus anticoagulant, the majority (60% and 76%, respectively) reacquired the antibody within 5 years. In contrast, of those who lost aCL IgM or IgA, fewer reacquired it within 5 years (37% and 17%, respectively).

Conclusion

Intermittent positivity of antiphospholipid antibodies is present in APS due to SLE. These fluctuations make it difficult to decide on length of anticoagulation. Lupus anticoagulant is more likely to persist post-thrombosis.

Recurrent thrombosis in patients with antiphospholipid antibodies and an initial venous or arterial thromboembolic event: A systematic review and meta-analysis

BACKGROUND

Patients with antiphospholipid antibodies (aPL) and thromboembolism (TE) are at risk for recurrent TE. Few studies, however, distinguish patients based on the initial event.

OBJECTIVES

We performed a systematic review and meta-analysis to investigate patients with aPL and venous TE (VTE), provoked or unprovoked, and patients with arterial TE (ATE).

PATIENTS/METHODS

We conducted searches in PubMed, CINAHL, Cochrane, and EMBASE. Inclusion criteria were prospective trials or cohort studies investigating patients with aPL and ATE or VTE. Excluded studies did not provide estimated recurrence rates, did not specify whether the incident event was ATE or VTE, included patients with multiple events, or included <10 patients. Two-year summary proportions were estimated using a random effects model.

RESULTS

Ten studies described patients with VTE, 2 with ATE, and 5 with VTE or ATE. The 2-year proportion for recurrent TE in patients with VTE who were taking anticoagulant therapy was 0.054 (95% confidence interval [CI], 0.037-0.079); the 2-year proportion for patients not taking anticoagulant therapy was 0.178 (95% CI, 0.150-0.209). Most studies did not distinguish whether VTE were provoked or unprovoked. The 2-year proportion for recurrent TE in patients with ATE who were taking anticoagulant therapy was 0.220 (95% CI, 0.149-0.311); the 2-year proportion for patients taking antiplatelet therapy was 0.216 (95% CI, 0.177-0.261).

CONCLUSIONS

Patients with aPL and ATE may benefit from a different antithrombotic approach than patients with aPL and VTE. Prospective studies with well-defined cohorts with aPL and TE are necessary to determine optimal antithrombotic strategies.

Recommendations of the Spanish Rheumatology Society for Primary Antiphospholipid Syndrome. Part I: Diagnosis, Evaluation and Treatment

OBJECTIVE

The difficulty in diagnosis and the spectrum of clinical manifestations that can determine the choice of treatment for primary antiphospholipid syndrome (APS) has fostered the development of recommendations by the Spanish Society of Rheumatology (SER), based on the best possible evidence. These recommendations can serve as a reference for rheumatologists and other specialists involved in the management of APS.

METHODS

A panel of four rheumatologists, a gynaecologist and a haematologist with expertise in APS was created, previously selected by the SER through an open call or based on professional merits. The stages of the work were: identification of the key areas for drafting the document, analysis and synthesis of the scientific evidence (using the Scottish Intercollegiate Guidelines Network [SIGN] levels of evidence) and formulation of recommendations based on this evidence and formal assessment or reasoned judgement techniques (consensus techniques).

RESULTS

46 recommendations were drawn up, addressing five main areas: diagnosis and evaluation, measurement of primary thromboprophylaxis, treatment for APS or secondary thromboprophylaxis, treatment for obstetric APS and special situations. These recommendations also include the role of novel oral anticoagulants, the problem of recurrences or the key risk factors identified in these subjects. This document reflects the first 21, referring to the areas of: diagnosis, evaluation and treatment of primary APS. The document provides a table of recommendations and treatment algorithms.

CONCLUSIONS

An update of the SER recommendations on APS is presented. This document corresponds to partI, related to diagnosis, evaluation and treatment. These recommendations are considered tools for decision-making for clinicians, taking into consideration both the decision of the physician experienced in APS and the patient. A partII has also been prepared, which addresses aspects related to obstetric SAF and special situations.

Management of thrombotic and obstetric antiphospholipid syndrome: a systematic literature review informing the EULAR recommendations for the management of antiphospholipid syndrome in adults

Objective

To perform a systematic literature review (SLR) informing the European Lmmendations for the management of antiphospholipid syndrome (APS) in adults.

Methods

A SLR through January 2018 was performed. Research questions were constructed using the Patient, Intervention, Comparator, Outcome (PICO) format. We included data from articles that reported on each relevant intervention. Summary effect estimates were calculated for direct comparison studies that matched the PICO question exactly, and for studies with the relevant intervention and comparator. When meta-analyses were available, we used these estimates.

Results

From 7534 retrieved articles (+15 from hand searches), 188 articles were included in the review. In individuals with high-risk antiphospholipid antibody (aPL) profile without prior thrombotic or obstetric APS, two meta-analyses showed a protective effect of low-dose aspirin (LDA) against thrombosis. Two randomised controlled trials (RCTs) and three cohort studies showed no additional benefit of treatment with vitamin K antagonists at target international normalised ratio (INR) 3–4 versus INR 2–3 in patients with venous thrombosis. In patients with arterial thrombosis, two RCTs and two cohort studies showed no difference in risk of recurrent thrombosis between the two target INR groups. One open-label trial showed higher rates of thrombosis recurrences in triple aPL-positive patients treated with rivaroxaban than those treated with warfarin. RCTs and cohort studies showed that combination treatment with LDA and heparin was more effective than LDA alone in several types of obstetric APS. SLR results were limited by the indirect evidence and the heterogeneity of patient groups for some treatments, and only a few high-quality RCTs.

Conclusion

Well-designed studies of homogeneous APS patient populations are needed.

How to Identify High-Risk APS Patients: Clinical Utility and Predictive Values of Validated Scores

PURPOSE OF REVIEW

Antiphospholipid syndrome (APS) is a clinical disorder characterised by thrombosis and/or pregnancy morbidity in the persistence of antiphospholipid (aPL) antibodies that are pathogenic and have pro-coagulant activities. Thrombosis in APS tends to recur and require prophylaxis; however, the stereotypical treatment for APS patients is inadequate and stratification of the thrombotic risks is important as aPL are prevalently observed in various diseases or elderly population.

RECENT FINDINGS

It is previously known that the multiple positive aPL or high titre aPL correlate to thrombotic events. To progress the stratification of thrombotic risks in APS patients and to quantitatively analyse those risks, antiphospholipid score (aPL-S) and the Global Anti-phospholipid Syndrome Score (GAPSS) were defined. These scores were raised from the large patient cohort data and either aPL profile classified in detail (aPL-S) or simplified aPL profile with classical thrombotic risk factors (GAPSS) was put into a scoring system. Both the aPL-S and GAPSS have shown a degree of accuracy in identifying high-risk APS patients, especially those at a high risk of thrombosis. However, there are several areas requiring improvement, or at least that clinicians should be aware of, before these instruments are applied in clinical practice. One such issue is standardisation of the aPL tests, including general testing of phosphatidylserine-dependent antiprothrombin antibodies (aPS/PT). Additionally, clinicians may need to be aware of the patient's medical history, particularly with respect to the incidence of SLE, which influences the cutoff value for identifying high-risk patients.

Anticoagulation in venous Thrombosis

Major studies addressing various aspects of the treatment of deep vein thrombosis are reviewed. It has lately been demonstrated that heparin should be dosed according to body weight and is preferably given as subcutaneous injections twice daily. Alternatively, low-molecular-weight heparins may be given in a fixed dose once daily, which does not require monitoring. Oral anticoagulation should be started concomitantly with heparin and targeted at an international normalized ratio of 2.0-3.0. This treatment should continue for a longer duration than previously accepted, in many cases for 6 months. For patients with contraindications to oral anticoagulation, secondary prophylaxis with a low-molecular-weight heparin is also effective and safe.

The treatment of anti-phospholipid syndrome: A comprehensive clinical approach

Anti-phospholipid syndrome (APS) is an acquired pro-thrombotic autoimmune disease that predisposes to thrombotic events and/or obstetric complications, in the persistent presence of anti-phospholipid antibodies (aPL). Life long moderate-intensity anticoagulation is the option of choice for aPL-positive patients with a previous thrombosis; critical issues concern the management of those with a history of arterial event due to the high rate of recurrence. Alternatives comprise anti-platelet agents and high-intensity anticoagulation. Low dose aspirin (LDASA) and low molecular weight heparin provide the mainstay of the treatment of obstetric APS, allowing a birth rate in 70% of cases. The management of refractory APS, thrombotic as well as obstetric, is highly debated, but an increasing burden of evidence points towards the beneficial effects of multiple treatments. Similarly, a management envisaging multiple drugs (anticoagulation, steroids, plasma exchange and/or intravenous immunoglobulins) is the most effective approach in catastrophic APS. Asymptomatic aPL carriers are at higher risk of thrombotic and obstetric complications compared to the general population, thus potentially benefitting of a pharmacological intervention. LDASA and hydroxychloroquine can be considered as options, in particular in case of high risk aPL profile, concomitant cardiovascular risk factors or associated autoimmune disease. APS is apparently a simple condition, but its multifaceted nature requires a complex and tailored treatment.

Complete Resolution of a Large Bicuspid Aortic Valve Thrombus with Anticoagulation in Primary Antiphospholipid Syndrome

Native aortic valve thrombosis in primary antiphospholipid syndrome (APLS) is a rare entity. We describe a 38-year-old man who presented with neurological symptoms and a cardiac murmur. Transthoracic echocardiography detected a large bicuspid aortic valve thrombus. Laboratory evaluation showed the presence of antiphospholipid antibodies. Anticoagulation was started, and serial echocardiographic studies showed complete resolution of the aortic valve vegetation after 4 months. The patient improved clinically and had no residual symptoms. This report and review of the literature suggests that vegetations in APLS can be treated successfully with conservative treatment, regardless of their size.

Massive Pulmonary Embolism in a Patient Using Warfarin at Therapeutic Dose

Warfarin sodium is commonly used for the prevention and treatment of thromboembolism. The efficacy of warfarin therapy depends on maintaining the International Normalised Ratio (INR) within the target range for the indication. A 56-year-old male presented to the emergency department with dyspnea and chest pain, together with pain and swelling in both legs. The patient had been taking warfarin at the therapeutic dose since having undergone an aortic valve replacement four years ago. His vital signs were an arterial pressure of 60/30 heart rate of 138 beats per minute, respiratory rate of 30 per minute and oxygen saturation of 60%. Computed tomography of the chest revealed thrombosis of the right pulmonary artery and its segmental branches. On investigating the aetiology of the venous thromboembolism, the level of Antithrombin III (AT III) activity was found to be at 37% (normal range, 80-120%).

Aortoiliac Thrombosis in Antiphospholipid Syndrome

Antiphospholipid syndrome is accepted as one of the most important causes of hypercoagulable states. Thrombotic events in patients with antiphospholipid syndrome, predominantly women, occur at a younger age than in those suffering from atherosclerotic disease. The majority of the thrombotic events affect the deep venous system of the lower limbs and arterial thrombosis predominates in the cerebral territory. The use of anticoagulant therapy prevents recurrent thrombosis but the duration and intensity of treatment remain controversial. Aortic disease is an anecdotal fact in the literature. A case of infrarenal aortic occlusion involving both iliac arteries associated with primary antiphospholipid syndrome is presented.

Prevalence of Antiphospholipid Antibodies and Lupus Anticoagulant in Juvenile Patients with Objectively Documented Deep-vein Thrombosis

The prevalence of lupus anticoagulant (LA) and antiphospholipid antibodies (APA) in young patients (<45 years) with deep-vein thrombosis (DVT) is not clearly defined yet. We studied 93 consecutive patients (36 males, 57 females; aged 15 to 45) with objectively documented DVT. A control group consisting of 100 nor mal, sex- and age-matched individuals was also investi gated. In all subjects, we evaluated prothrombin time (PT), partial thromboplastin time (PTT), AT III antigen and activity, protein C antigen and activity, free and total protein S antigen and protein S activity, fibrinogen, plas minogen, heparin cofactor II, plasminogen activator in hibitor (PAI), lupus anticoagulant (LA), and APA. For the assessment of LA, we used the PTT-LA kit (Boeh ringer Mannheim, Milan, Italy) as a screening test, with mixing studies with the Staclot-PNP kit and the Staclot- LA kit (Boehringer Mannheim, Milan, Italy) as confirma tory procedures. For the detection of APA, we used a commercially available enzyme-linked immunoassay (ELISA) (Asserachrom APA, Boehringer Mannheim, Mi lan, Italy). History was elicited in all patients to deter mine if the thrombotic episode was idiopathic or the re sult of a well-identified risk factor. LA was found in 11 (11.8%) patients. APA were positive in 13 (14%) and bor derline in 19 (20.4%) patients. In the control group, no patients were positive for LA or APA, but five exhibited borderline APA levels. LA was significantly more fre quent (p = 0.05) in patients with idiopathic DVT than in patients with secondary DVT; no difference was found for APA (p > 0.5). An inherited coagulation defect was found in seven (7.5%) patients. Our data suggest that the presence of LA or APA is associated with an increased incidence of thrombotic manifestation in young patients. Moreover LA is more frequent in patients with idiopathic DVT. Because the incidence of recurrent thrombotic manifestations in patients with LA or APA is estimated to be ∼50% within 2 years from the first thrombotic episode, the tests should be performed in all patients with juvenile thrombosis.

Acute-Sinus Thrombosis in a Child with Antibodies against Cardiolipins

A case of thrombosis of the straight sinus and the left transverse sinus in an 11 year old boy is described. The patient had a history of slight trauma followed by infection of the upper airways and presented with severe impressive and expressive dysphasia and stupor.

He was treated with in situ fibrinolysis. Despite successful local fibrinolysis and thrombectomy with a balloon catheter the patient rethrombosed his left transverse sinus several times and had a late thrombosis of his jugular vein.

Nevertheless, flow in the left sigmoid sinus was facilitated and focal brain oedema was significantly reduced.

Serum levels of antibodies against cardiolipins, associated with venous thrombosis, were elevated and interfered with reagents used for measuring the activated partial tromboplastin time, causing it to be falsely prolonged with subsequent underdosage of heparin. He was treated with oral anticoagulants for one year after the episode and recovered completely.

Current status and future prospects for the treatment of antiphospholipid syndrome

Antiphospholipid syndrome (APS) is a prothrombotic disease characterized by thrombosis and pregnancy morbidity in the presence of antiphospholipid antibodies (apL). Management of thrombosis is based on long-term oral anticoagulation and patients with arterial events should be treated aggressively. Primary thrombo-prophylaxis is recommended in patients with systemic lupus erythromatosus (SLE) and obstetric APS. Obstetric APS care is based on high-risk management and treatment with aspirin and heparin. Possible future therapies include statins, hydroxychloroquine, rituximab, and new anticoagulant drugs. Current research is focused on targeting components of the complement system, interfering with aPL-mediated cell activation and using tailored peptides to block the pathogenic subpopulation of aPL.

A Case of Superior Mesenteric Artery Thrombosis Associated With Transient Elevation of Antiphospholipid Antibodies

Transient elevation of antiphospholipid antibody (APLA) is commonly observed in cases of viral infection; however, it is generally not associated with clinical thromboembolic events. In this report, we present a rare case of superior mesenteric artery (SMA) thrombosis associated with a transient elevation of APLA and discuss its relationship with fibromuscular dysplasia and adenomyosis of the uterus. Furthermore, we discuss the use of anticoagulant therapy in cases with transient elevation of APLA. In this case, a 46-year-old woman with no significant medical history was diagnosed with intestinal stenosis after SMA thrombosis that had been resolved with anticoagulant therapy. Laboratory examination showed elevated levels of anticardiolipin antibody. Resection of the stenosed ileum and hysterectomy for huge adenomyosis were performed. Anticardiolipin antibody level normalized 4 months after the operation. Anticoagulant therapy was withdrawn after anticardiolipin antibody normalized, and the patient has been free from thromboembolic events ever since. Transient elevation of APLA should be kept in mind in all patients with thromboembolic events, including those with no medical history of collagen diseases or infection. In the present case, association with fibromuscular dysplasia and adenomyosis of the uterus is suspected, but further investigation is required. Once the APLA level normalizes with the resolved thrombus, decision of withdrawing the anticoagulant therapy can be considered.

Treatment of Thrombotic Antiphospholipid Syndrome: The Rationale of Current Management-An Insight into Future Approaches

Vascular thrombosis and pregnancy morbidity represent the clinical manifestations of antiphospholipid syndrome (APS), which is serologically characterized by the persistent positivity of antiphospholipid antibodies (aPL). Antiplatelet and anticoagulant agents currently provide the mainstay of APS treatment. However, the debate is still open: controversies involve the intensity and the duration of anticoagulation and the treatment of stroke and refractory cases. Unfortunately, the literature cannot provide definite answers to these controversial issues as it is flawed by many limitations, mainly due to the recruitment of patients not fulfilling laboratory and clinical criteria for APS. The recommended therapeutic management of different aPL-related clinical manifestations is hereby presented, with a critical appraisal of the evidence supporting such approaches. Cutting edge therapeutic strategies are also discussed, presenting the pioneer reports about the efficacy of novel pharmacological agents in APS. Thanks to a better understanding of aPL pathogenic mechanisms, new therapeutic targets will soon be explored. Much work is still to be done to unravel the most controversial issues about APS management: future studies are warranted to define the optimal management according to aPL risk profile and to assess the impact of a strict control of cardiovascular risk factors on disease control.

Thrombophilia Screening

Although controversial, screening for thrombophilia has become common. Testing for antiphospholipid antibodies is indicated in order to guide treatment decisions if there is clinical suspicion for antiphospholipid syndrome. The utility of identifying other thrombophilias in symptomatic venous thromboembolism (VTE) is questionable, as the risk of recurrence does not appear to be increased by an appreciable degree with the most common disorders (heterozygosity for factor V Leiden or prothrombin mutation). Although recurrence appears to be increased in those with homozygous or multiple abnormalities and potentially deficiencies in natural anticoagulants, screening to detect these conditions is difficult to justify based on their rarity. The American College of Chest Physicians' current guidelines note the increased risk of recurrence with idiopathic, proximal events regardless of thrombophilia status. They suggest duration of anticoagulation therapy be based on location and provoking factors rather than whether or not the individual has a thrombophilia. Because routine prophylaxis in asymptomatic individuals with thrombophilia is not recommended, screening of asymptomatic family members is difficult to justify. Screening prior to prescribing combination oral contraceptives is not cost effective, may result in unwanted pregnancies, and may have little effect on the overall rate of VTE.

Antiphospholipid antibodies and the risk of recurrence after a first episode of venous thromboembolism: a systematic review

The quality of evidence pertaining to the risk of recurrent thrombosis among patients with an antiphospholipid antibody is very low. Additional studies are needed to define the impact of APLA testing on clinical decision-making.

Thrombosis in systemic lupus erythematosus: a review article

Thrombosis is a well-known clinical entity in systemic lupus erythematosus (SLE), and it is multifactorial. The most important risk factor is the presence of antiphospholipid antibodies (APLAs). However, approximately 40% of adults with SLE who are negative for APL A are diagnosed with thrombosis, indicating the importance of other risk factors. Thus, the thrombosis risk factors should be evaluated extensively and regularly and treated aggressively in every patient with systemic lupus erythematosus.

Antiphospholipid syndrome and recurrent thrombosis--limitations of current treatment strategies

Antiphospholipid syndrome (APS) is a systemic autoimmune disorder that is characterised by the presence of antiphospholipid antibodies and a common cause of vascular thromboembolic phenomena. The management of patients with APS is currently directed to antithrombotic medications. The international therapeutic guidelines recommend oral anticoagulation with warfarin indefinitely after the first thrombotic episode. However, therapeutic guidelines lack for a minority group of patients - the patients appropriately anticoagulated with recurrent thromboembolic phenomena. The authors present a clinical report that reveals the therapeutic and diagnostic complexity of this specific group of patients. Regarding recent studies, APS has been revealed as a complex syndrome with multiple pathophysiological mechanisms previously unknown. In this context, new therapeutic approaches have been defended and empirically experienced, with potentially promising results.

Management of the antiphospholipid syndrome

Antiphospholipid syndrome (APS) is characterized by recurrent venous or arterial thromboses, fetal losses and thrombocytopenia in the presence of antiphospholipid antibodies, namely lupus anticoagulant, anticardiolipin antibodies or antibodies directed to various proteins, mainly β2 glycoprotein I, or all three. There is consensus in treating patients with APS and first venous thrombosis with oral anticoagulation to a target international normalized ratio (INR) of 2.0-3.0. A recent systematic review recommended a target INR of >3.0 in those patients with APS and arterial thrombosis. The approach in women with obstetric manifestations of APS is based on the use of aspirin plus heparin. The best treatment for patients with the catastrophic variant of the APS is a combination of anticoagulation, corticosteroids, and plasma exchange or intravenous immunoglobulins.

Cardiovascular events in patients with antiphospholipid antibodies: strategies of prevention

Antiphospholipid antibodies are a heterogeneous group of auto-antibodies against phospholipids-binding proteins. The antiphospholipid syndrome is an autoimmune disorder characterized by the clinical association of antiphospholipid antibodies with a condition of hypercoagulability that can affect any blood vessel. Involvement of larger vessels, such as arteries or veins, manifests in the form of thrombosis or thromboembolism, whereas involvement of small vessels manifests as thrombotic micro-angiopathy. The antiphospholipid syndrome is also characterized by the presence of recurrent fetal loss. Patients who are persistently positive for antiphospholipid tests, and who have an arterial thrombosis or venous thrombosis history, are at increased risk of recurrence. Oral anticoagulant therapy is the mainstay of treatment for the thrombotic manifestations of the syndrome. Therapy with anticoagulant drugs should be long-term. On the other hand, although the thromboembolic potential of antiphospholipid antibodies has been well documented, there is still no general consensus on the prophylactic treatment of antiphospholipid antibodies carriers who have never developed vascular/obstetric manifestations. The effect of primary prophylaxis in antiphospholipid antibodies positive individuals is not well known and no evidence-based recommendations exist for thrombosis prevention in these individuals. However, the presence of risk factors for thrombosis increases the risk of first event of antiphospholipid antibodies positive patients. In conclusion, there is still much to learn on primary prophylaxis of asymptomatic antiphospholipid antibodies carriers. Hopefully, evidence-based guidelines will be available in the future.

Controversies in the antiphospholipid syndrome: can we ever stop warfarin?

Patients with antiphospholipid syndrome are at increased risk for recurrent arterial and venous thrombosis and therefore benefit from long term warfarin therapy. The optimal duration of warfarin therapy after a first venous thromboembolic event is however a matter of some controversy and many questions remain unanswered. After reviewing and analysing the available evidence, we discuss some common scenarios in everyday clinical practice where treatment decisions are difficult.

[The management of thrombosis in the antiphospholipid antibody syndrome: insights from recent clinical trials and remaining unsolved issues]

The antithrombotic therapy of the antiphospholipid syndrome (APS) has long been based on an empirical strategy. In the absence of appropriate randomised controlled trials, data of retrospective cohort studies were used to establish these strategies. Here we report the results of recent clinical trials, what they add to patient management and the issues that remain unsolved. SECONDARY PROPHYLAXIS OF THROMBOTIC EVENTS: While there is a consensus for prolonged vitamin K antagonist anticoagulation after a first event, two recent randomised clinical trials have compared various intensities of anticoagulation. Both studies have shown that high intensities of warfarin were not superior to conventional intensities. Patients included in these studies had mainly venous thromboembolic events. There has been no study comparing different antithrombotic strategies for arterial thrombosis associated with APS. The WARSS/APASS study, in particular has not been conducted in patients with definite APS and should not be applied to these patients. For now, vitamin K antagonist anticoagulants should remain the treatment of choice in these patients. PRIMARY PROPHYLAXIS OF THROMBOTIC EVENTS: Because of the high incidence of thrombotic events in asymptomatic patients with antiphospholipid antibodies, especially in systemic lupus erythematosus, a clinical trial compared aspirin and placebo in this setting. This study did not demonstrate any benefit of aspirin. We conclude that recent clinical trials indicate the optimal antithrombotic strategy in APS with venous thromboembolism. However, the best options for patients with arterial thrombosis and for primary prophylaxis remain to be established by further studies.

Controversies and unresolved issues in antiphospholipid syndrome pathogenesis and management

While much is understood concerning the clinical features of patients with antiphospholipid syndrome (APS), many issues remain. The proper designation of patients with "definite" APS and the correct categorization of patients by both laboratory and clinical features are matters of ongoing debate. Recent proposals have identified new subsets of patients who have many typical features of APS but either do not fit the criteria for a "definite" diagnosis or have initially negative laboratory tests for antiphospholipid antibodies. Meanwhile, decisions about laboratory tests are based on expert opinion, rather than the results of controlled trials. As for treatment, many guidelines are offered, but few are backed by data from strong clinical trials. This article summarizes the clinical questions remaining to be answered and debates concerning pathogenesis, diagnosis, and management.

The treatment of antiphospholipid syndrome: a harmonic contrast

The antiphospholipid syndrome (APS) is characterized by a wide variability in clinical manifestations. Recommendations for therapy are conditioned by the lack of appropriate studies, due either to methodological limitations or excessive selection of patients. There is consensus in treating patients with APS and first venous thrombosis with warfarin to a target international normalized ratio (INR) of 2.3-3.0. However, a recent systematic review including observational studies found patients with APS and stroke to be at a high risk of recurrent events. We thus recommend a target INR>3.0 in this group. Likewise, the optimal approach for women with obstetric manifestations of APS is not completely defined; some authors recommend universal aspirin plus heparin whereas others consider aspirin in monotherapy useful for women with recurrent early miscarriage only. Correction of vascular risk factors and a high-risk management of pregnancy, including Doppler studies of the uterine and umbilical vessels, are warranted. Hydroxychloroquine and statins are likely to become important in the future.

A systematic review of secondary thromboprophylaxis in patients with antiphospholipid antibodies

OBJECTIVE

To systematically review the efficacy and safety data of different therapeutic approaches in patients with antiphospholipid antibodies (aPL) and thrombosis.

METHODS

The Medline database and references from selected reports and review articles were used. Randomized controlled trials, prospective and retrospective cohort studies, and subgroup analysis (n > 15) that focused on the secondary thromboprophylaxis in patients with aPL were selected.

RESULTS

Sixteen studies were selected. Patients with venous events and a single test for aPL showed a low recurrence rate while receiving oral anticoagulation at a target international normalized ratio (INR) of 2.0-3.0. Patients with stroke and a single positive aPL test had no increased risk compared with those without aPL. Recurrence rates in patients with definite antiphospholipid syndrome (APS) and previous venous thromboembolism were lower than in patients with arterial and/or recurrent events, both with and without therapy. Only 3.8% of recurrent events occurred at an actual INR >3.0. Mortality due to recurrent thrombosis was higher than mortality due to bleeding (18 patients versus 1 patient reported).

CONCLUSION

For patients with definite APS, we recommend prolonged warfarin therapy at a target INR of 2.0-3.0 in APS patients with first venous events and >3.0 for those with recurrent and/or arterial events. For patients with venous thromboembolism or stroke and a single positive aPL test, we recommend further testing to determine if they have a persisting antibody. If they do not, the same therapy as for the general population should be used (warfarin at a target INR of 2.0-3.0 and low-dose aspirin, respectively).

The antiphospholipid syndrome

The antiphospholipid syndrome (APS) is an autoimmune disorder characterized by the clinical association of antiphospholipid autoantibodies (aPL) with a syndrome of hypercoagulability that can affect any blood vessel, irrespective of type or size. Involvement of larger vessels, such as arteries or veins, manifests in the form of thrombosis or embolism, whereas involvement of smaller vessels, including capillaries, arterioles, and venules, manifests as thrombotic microangiopathy. Virtually any organ in the body, including the kidney, can be affected. Here, we review the basic principles and recent advances in our understanding of APS, and discuss the broad spectrum of renal diseases that have been observed in association with this syndrome. We also discuss the impact that APS may have on pre-existing renal disease as well as current recommendations for treatment of APS.

Aspirin for primary thrombosis prevention in the antiphospholipid syndrome: A randomized, double-blind, placebo-controlled trial in asymptomatic antiphospholipid antibody–positive individuals

OBJECTIVE

To determine the efficacy of a daily dose of 81 mg aspirin in primary thrombosis prevention in asymptomatic, persistently antiphospholipid antibody (aPL)-positive individuals (those with positive aPL but no vascular and/or pregnancy events).

METHODS

The Antiphospholipid Antibody Acetylsalicylic Acid (APLASA) study was a multicenter, randomized, double-blind, placebo-controlled clinical trial in which asymptomatic, persistently aPL-positive individuals were randomized to receive a daily dose of 81 mg of aspirin or placebo. In a separate observational and parallel study, asymptomatic, persistently aPL-positive individuals who were taking aspirin or declined randomization were followed up prospectively.

RESULTS

In the APLASA study, 98 individuals were randomized to receive aspirin or placebo (mean +/- SD followup period 2.30 +/- 0.95 years), of whom 48 received aspirin and 50 received placebo. In the observational study, 74 nonrandomized individuals were followed up prospectively (mean +/- SD followup period 2.46 +/- 0.76 years); 61 received aspirin and 13 did not. In the APLASA study, the acute thrombosis incidence rates were 2.75 per 100 patient-years for aspirin-treated subjects and 0 per 100 patient-years for the placebo-treated subjects (hazard ratio 1.04, 95% confidence interval 0.69-1.56) (P = 0.83). Similarly, in the observational study, the acute thrombosis incidence rates were 2.70 per 100 patient-years for aspirin-treated subjects and 0 per 100 patient-years for those not treated with aspirin. All but 1 patient with thrombosis in either study had concomitant thrombosis risk factors and/or systemic autoimmune disease at the time of thrombosis.

CONCLUSION

Our results suggest that asymptomatic, persistently aPL-positive individuals do not benefit from low-dose aspirin for primary thrombosis prophylaxis, have a low overall annual incidence rate of acute thrombosis, and develop vascular events when additional thrombosis risk factors are present.

Duration of vitamin K antagonist therapy for venous thromboembolism: a systematic review of the literature

PURPOSE

The aim of this study was to evaluate the evidence on the optimal duration of vitamin K antagonist (VKA) therapy for venous thromboembolism (VTE).

METHODS

Randomized controlled trials of VKA for VTE were identified by a computerized database search. Summary event rates for relevant outcomes were calculated using a random effects model with 95% confidence intervals (95% CI).

RESULTS

Ten studies met inclusion criteria. The incidence of recurrent VTE (3 months, 7.9 VTE per 100 patient-years [95% CI, 5.2 to 10] versus 4-12 months, 4.9 VTE per 100 patient-years [95% CI, 3.6 to 6.2] versus continuous therapy, 0.7 VTE per 100 patient-years [95% CI, 0.3 to 1.1]) and total adverse events (3 months, 11.2 events per 100 patient-years [95%CI, 7.1 to 15.4] versus 4-12 months, 7.4 events per 100 patient-years [95%CI, 6.2 to 8.5] versus continuous therapy 3.1 events per 100 patient-years [95%CI, 2.2 to 4.0] declined as VKA therapy duration increased. Continuous reduced intensity therapy (INR 1.5-2) was associated with more recurrent VTE (2.3 VTE per 100 patient-years [95%CI, 1.5 to 3.0]). Continuous VKA therapy (INR 2-3) was beneficial for patients with a second VTE and antiphospholipid antibodies. The incidence of recurrent VTE was similar with 6 or 12 weeks of therapy for isolated calf DVT.

CONCLUSION

Randomized controlled trials indicate that continuous VKA therapy (INR 2-3) for VTE is associated with better clinical outcomes than shorter durations. Patients with a second VTE or antiphospholipid antibodies also benefit from continuous anticoagulation. Patients with calf DVT should be treated for at least 6 weeks.