An update on the management of antiphospholipid syndrome

Positive antiphospholipid antibodies increase the risk of ischemic stroke in patients with atrial fibrillation

BACKGROUND

Antiphospholipid antibodies (aPL), including lupus anticoagulant, antibodies against β2 glycoprotein I (anti-β2GPI), and anticardiolipin (aCL) antibodies are associated with ischemic stroke (IS). Their prevalence and clinical relevance in atrial fibrillation (AF) remain unclear.

OBJECTIVES

To assess whether aPL are associated with increased risk of IS in AF patients despite anticoagulation.

METHODS

We conducted a post hoc analysis of aPL using blood samples from 243 consecutive AF patients enrolled in a cohort study. Markers of a prothrombotic state, including endogenous thrombin potential, fibrin clot permeability, and lysis time, were measured at baseline. During a median follow-up of 52 months, IS/transient ischemic attack and major bleeding were recorded.

RESULTS

We observed aPL at a moderate or high titer in 51 (21%) patients, including 17 (7%) with anti-β2GPI, 19 (7.8%) with aCL antibodies, and 37 (15.2%) with lupus anticoagulant. aPL-positive patients were more likely to have prior stroke (P = .01) and be active smokers (P = .03), along with increased endogenous thrombin potential (P = .02), without any changes in fibrin clot properties. Anti-β2GPI (hazard ratio, 4.38; 95% CI, 1.58-12.19) and aCL (hazard ratio, 4.70; 95% CI, 1.80-12.30) at a moderate or high titer were associated with IS during follow-up (n = 20; 1.9% per year). There were 23 major bleedings (2.1% per year) and 20 deaths (1.9% per year), which were not associated with aPLs.

CONCLUSION

Our study showed a relatively high prevalence of aPL positivity in AF patients, which was linked to an increased risk of IS/transient ischemic attack. This suggests that screening for aPL might help optimize anticoagulant therapy in such patients.

Catastrophic antiphospholipid syndrome after pregnancy complicated by hemolysis, elevated liver enzymes and low platelets syndrome

Background

Antiphospholipid syndrome (APLS) is rarely complicated by catastrophic antiphospholipid syndrome (CAPS). Peripartum CAPS is rarer still and can masquerade as other obstetric disorders. A high degree of suspicion is critical for early diagnosis and specific management given the significant morbidity and mortality associated with this disorder.

Case

We report a case of a 27-year-old at 22 week's gestation with a history of APLS found to have severe hemolysis, elevated liver enzymes and low platelets (HELLP) syndrome, resulting in termination of pregnancy. Further workup revealed the diagnosis of CAPS followed by prompt treatment with triple therapy leading to clinical improvement.

Conclusion

CAPS should be considered within the differential in an obstetric patient with a history of APLS who has evidence of multiorgan involvement with macro- or microvascular thrombosis. Although this may mimic alternative disorders, prompt diagnosis is imperative for appropriate therapy and reduction in maternal morbidity and mortality.

Pediatric catastrophic antiphospholipid syndrome with extensive skin involvement

Antiphospholipid syndrome (APS) is a state of hypercoagulability due to persistent antiphospholipid antibodies (aPLs) in the blood. Catastrophic APS (CAPS) is a severe form with higher morbidity and mortality in which there occurs widespread thrombosis in multiple organs and hence warrants early diagnosis and aggressive management. We report a case of pediatric CAPS with extensive cutaneous involvement precipitated by infection successfully treated with the combination of high dose systemic corticosteroids, antibiotics, long-term anticoagulation, and wound care.

Understanding the Pathophysiology of Preeclampsia: Exploring the Role of Antiphospholipid Antibodies and Future Directions

Preeclampsia (PE) is a hypertensive disorder in pregnancy associated with significant fetal and maternal complications. Antiphospholipid syndrome (APS) is an acquired form of thrombophilia characterized by recurrent venous or arterial thrombosis and obstetric complications that significantly increases morbidity and mortality rates. While preeclampsia may not be the most prevalent obstetric complication in APS, it significantly impacts the long-term health of both mother and child. The treatment of preeclampsia in antiphospholipid syndrome is different from the treatment of preeclampsia as an independent disease. Despite current treatments involving anticoagulants, antiplatelet agents, and antihypertensive drugs, obstetric complications may persist, underscoring the need for cohesive management and effective treatments. The objective of our review is to briefly present knowledge about the physiopathology of preeclampsia and the role of antiphospholipid antibodies in this process. Based on the existing literature, our review aims to identify future directions in molecular pathology toward the discovery of biomarkers and targeted treatments. The application of multidisciplinary approaches and prognostic models, including new biomarkers, could be beneficial in the prediction of PE.

Antiphospholipid antibody syndrome complicating infective endocarditis - case report

A 37-year-old lady with infective endocarditis of the mitral valve presented in congestive cardiac failure. However, the clinical scenario became complicated when she was also found to have antiphospholipid antibody syndrome. Meticulous optimization and timely surgical intervention by a multidisciplinary team helped mitigate this not so common situation and lead to successful outcome.

Stability of Anticoagulation Following Acenocoumarin in Stroke Patients: Role of Pharmacogenomics and Acquired Factors

OBJECTIVE

Pharmacogenomics plays an important role in drug metabolism. A stable anticoagulation is important for primary and secondary prevention of cardioembolic stroke and cerebral venous sinus thrombosis (CVST). We report the role of cytochrome P450 ( CYP2C9*2/*3 ) and vitamin K epoxide reductase subunit 1 ( VKORC1 ) genotypes and acquired causes in maintaining stability of anticoagulation following acenocoumarin in cardioembolic stroke and CVST.

METHODS

The study comprised 157 individuals with cardioembolic stroke and CVST who were on acenocoumarin. Their comorbidities, comedication, and dietary habits were noted. Prothrombin time and international normalized ratio (INR) were measured during follow-up, and the coagulation status was categorized as stable (>50% occasions in therapeutic range) and unstable (>50% below and above therapeutic range). Genotyping of VKORC1 , CYP2C9*2 , and CYP2C9*3 was done by polymerase chain reaction-restriction fragment length polymorphism. Bleeding and embolic complications were noted. The predictors of unstable INR were evaluated using multivariate analysis.

RESULTS

INR was stable in 47.8% and unstable in 52.2% of patients. Patients with mutant genotypes required low dose of acenocoumarin. The predictors of unstable INR were metallic valve (odds ratio [OR] 4.07, 95% confidence interval [CI] 1.23-13.49, P = 0.02), use of digoxin (OR 0.031, 95% CI 0.13-0.74, P = 0.09), proton pump inhibitor (OR 0.23, 95% CI 0.06-0.91, P = 0.037), sodium valproate (OR 0.22, 95% CI 0.05-0.85, P = 0.029), and CYP2C9*2 genotype (OR 5.57, 95% CI 1.19-26.06, P = 0.02).

CONCLUSIONS

Variant genotypes of VKORC1 , CYP2C9*2 , and CYP2C9*3 required lower dose of acenocoumarin, and CYP2C9*2 was associated with unstable INR. Comedication is a modifiable risk factor that needs attention.

Systemic Lupus Erythematosus and Lupus Nephritis Presenting as Severe Constitutional Symptoms

Systemic lupus erythematosus (SLE) is a remitting-relapsing systemic autoantibody and immune complex disease with a similar clinical presentation to that of malignancy and infection. The authors report a case of newly diagnosed SLE and lupus nephritis in a 48-year-old woman with constitutional symptoms and unintentional weight loss. Her presentation was further complicated by pericardial effusion and methicillin-resistant Staphylococcus aureus (MRSA) facial cellulitis and bacteremia. In the context of nonspecific symptoms and a wide initial differential diagnosis, the early consideration of rheumatologic etiologies and the involvement of consultant services led to appropriate diagnostic testing and a timely diagnosis.

A thrombin-driven neural net diagnoses the antiphospholipid syndrome without the need for interruption of anticoagulation

ABSTRACT

Thrombosis is an important manifestation of the antiphospholipid syndrome (APS). The thrombin generation (TG) test is a global hemostasis assay, and increased TG is associated with thrombosis. APS is currently diagnosed based on clinical and laboratory criteria, the latter defined as anti-cardiolipin, anti-β2-glycoprotein I antibodies, or lupus anticoagulant (LA). APS testing is often performed after a thrombotic episode and subsequent administration of anticoagulation, which might hamper the interpretation of clotting assays used for LA testing. We set out to develop an artificial neural network (NN) that can diagnose APS in patients who underwent vitamin K antagonist (VKA) treatment, based on TG test results. Five NNs were trained to diagnose APS in 48 VKA-treated patients with APS and 64 VKA-treated controls, using TG and thrombin dynamics parameters as inputs. The 2 best-performing NNs were selected (accuracy, 96%; sensitivity, 96%-98%; and specificity, 95%-97%) and further validated in an independent cohort of VKA-anticoagulated patients with APS (n = 33) and controls (n = 62). Independent clinical validation favored 1 of the 2 selected NNs, with a sensitivity of 88% and a specificity of 94% for the diagnosis of APS. In conclusion, the combined use of TG and NN methodology allowed for us to develop an NN that diagnoses APS with an accuracy of 92% in individuals with VKA anticoagulation (n = 95). After further clinical validation, the NN could serve as a screening and diagnostic tool for patients with thrombosis, especially because there is no need to interrupt anticoagulant therapy.

Antiphospholipid Syndrome: State of the Art of Clinical Management

Antiphospholipid syndrome (APS) is a systemic autoimmune disorder clinically characterized by recurrent arterial and venous thrombosis and/or pregnancy morbidity in the presence of antiphospholipid antibodies. Currently, treatment is mainly focused on anticoagulation, but therapies targeting mechanisms involved in APS autoimmune pathogenesis could play an important role in specific settings. An evidence-based therapeutic approach is limited by the broad clinical spectrum of the syndrome and the nature of a "rare disease" that makes it difficult to carry out well-designed prospective studies. Vitamin K antagonists (AVK), notably warfarin, are the standard treatment for preventing recurrent venous thrombosis and perhaps also arterial thrombosis. Direct oral anticoagulants (DOACs) are not recommended at least in patients with triple positivity APS. Treatment options for the prevention of pregnancy complications in obstetric APS, as combined use of aspirin and heparin, low-dose prednisolone, hydroxychloroquine, intravenous immunoglobulin (IVIG), may improve pregnancy outcome. The catastrophic antiphospholipid syndrome (CAPS) is the most severe form of APS with acute multiple organ involvement and small vessel thrombosis. Glucocorticoids, heparin, plasma exchange or IVIG, rituximab, or eculizumab must be added to concurrent treatment of precipitating factors (e.g. infections) as rescue therapies. Finally, it has been observed that SARS COV2 infection may produce vascular complications mimicking the clinical and pathophysiological features of APS and particularly of CAPS. From this point of view, attention has been focused on the "protective" role of anticoagulant therapy in preventing thrombotic complication when these clinical conditions coexist.

Advances in Management of the Stroke Etiology One-Percenters

PURPOSE OF REVIEW

Uncommon causes of stroke merit specific attention; when clinicians have less common etiologies of stoke in mind, the diagnosis may come more easily. This is key, as optimal management will in many cases differs significantly from "standard" care.

RECENT FINDINGS

Randomized controlled trials (RCT) on the best medical therapy in the treatment of cervical artery dissection (CeAD) have demonstrated low rates of ischemia with both antiplatelet and vitamin K antagonism. RCT evidence supports the use of anticoagulation with vitamin K antagonism in "high-risk" patients with antiphospholipid antibody syndrome (APLAS), and there is new evidence supporting the utilization of direct oral anticoagulation in malignancy-associated thrombosis. Migraine with aura has been more conclusively linked not only with increased risk of ischemic and hemorrhagic stroke, but also with cardiovascular mortality. Recent literature has surprisingly not provided support the utilization of L-arginine in the treatment of patients with mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes (MELAS); however, there is evidence at this time that support use of enzyme replacement in patients with Fabry disease. Additional triggers for reversible cerebral vasoconstriction syndrome (RCVS) have been identified, such as capsaicin. Imaging of cerebral blood vessel walls utilizing contrast-enhanced MRA is an emerging modality that may ultimately prove to be very useful in the evaluation of patients with uncommon causes of stroke. A plethora of associations between cerebrovascular disease and COVID-19 have been described. Where pertinent, authors provide additional tips and guidance. Less commonly encountered conditions with updates in diagnosis, and management along with clinical tips are reviewed.

Catastrophic antiphospholipid syndrome immediately after coronary angiography: the unexpected complication

A 44-year-old woman with obstetric antiphospholipid syndrome (APS) presented to our institution with suspected non ST-elevation myocardial infarction (NSTEMI). Shortly after coronary angiography, she developed diplopia, hypotension and chest pain with inferior ST elevation in 12-lead ECG. According to multidisciplinary evaluation, she promptly underwent systemic thrombolysis, with clinical and haemodynamic improvement. Eventually, a diagnosis of catastrophic APS was made, with multiorgan ischemic involvement confirmed by blood examinations and multimodal imaging techniques. A pluridisciplinary approach was central to define optimal medical therapy and in-hospital management that lead to clinical condition improvement at discharge. In this case, catastrophic APS was triggered or worsened by catheters insertion and invasive manoeuvres within the arterial lumen during coronary angiography. Recognizing catastrophic APS and its potential triggers, can be helpful to deliver prompt and accurate medical assistance. Moreover, in APS patients undergoing coronary angiography, preventive strategies are important to prevent possible unfavourable evolution in catastrophic APS.

Corticosteroids, Plasmapheresis, Argatroban, Rituximab, and Sirolimus Provided Clinical Benefit for Catastrophic Antiphospholipid Syndrome in a Patient with a History of Heparin-Induced Thrombocytopenia

We report a patient with catastrophic antiphospholipid syndrome who had significant improvement after corticosteroids, plasmapheresis, argatroban, rituximab, and sirolimus. Argatroban was used instead of heparin due to a history of heparin-induced thrombocytopenia.

Evaluation of patients with antiphospholipid syndrome subsequently COVID-19 vaccinations: A retrospective cohort study

The aim of this study is to evaluate development of side effects, thrombotic or obstetric complications in our antiphospholipid syndrome (APS) patient group, after vaccination against coronavirus disease 2019 (COVID-19). A cohort was formed from patients who have previously been followed up with a diagnosis of APS. The patients of the cohort were evaluated retrospectively to find out if they were vaccinated with CoronaVac and/or BNT162b2 vaccines which are being used in our country. To evaluate the side effects seen after the vaccination, the information was collected by the patients in their outpatient appointments or making a phone call. Thirty-five APS patients who had received at least 1 dose of any of the COVID-19 vaccines were included in the study. Median (min-max) number of vaccine doses per patient was 2 (1-3). Eleven patients had a booster dose after primary vaccination. Twenty patients were ever vaccinated with BNT162b2 and 18 with CoronaVac. Among BNT162b2 recipients, 9 (45.0%) and among CoronaVac recipients 15 (42.9%) reported an adverse event after a vaccine administration. The most common adverse events were myalgia and malaise after any dose of both vaccines. No vaccine-related new thrombotic events or APS flares were observed. Our results were comparable with those reported in the literature. Comprehensive large-scale studies are needed for more accurate results on the evaluation of side effects after COVID-19 vaccination in APS patients.

Emerging Therapies in Antiphospholipid Syndrome

The antiphospholipid syndrome (APS) is the most common cause of acquired immune-mediated thrombophilia. This syndrome is broadly defined by the presence of arterial or venous thrombosis, or pregnancy morbidity, in the presence of high levels of antiphospholipid antibodies. Despite recognition of this disorder more than 50 years ago, a fundamental unifying pathogenesis has not been determined. Due to this, mechanism-based therapies for APS are not available, and current management following thrombotic events suggests anticoagulation of indeterminate duration, or for obstetric complications, heparin/low molecular weight heparin and aspirin. However, APS is an autoimmune disorder, and several approaches focused on modulating the immune response or its effectors have been employed. Those which have been most extensively studied include hydroxychloroquine, rituximab and eculizumab, an inhibitor of complement C5. In this report, we review in depth, and critique, key clinical studies of these agents. Since all of these studies are small, our conclusions are qualified. However, it appears that hydroxychloroquine may enhance the anticoagulant efficacy of vitamin K antagonists in APS patients, and that rituximab may ameliorate some of the "non-criteria" manifestations of APS. The catastrophic antiphospholipid syndrome (CAPS) is associated with diffuse thrombosis, multi-organ dysfunction, and ∼30% mortality. A high incidence of complement regulatory gene mutations, and compelling data concerning the efficacy of eculizumab in CAPS, suggests an important role for complement in this disorder. However, additional work is needed to clarify the role of complement in non-catastrophic APS, though emerging data suggests that complement inhibition may be effective in preventing thrombosis in these patients as well.

Point of care testing to monitor INR control in patients with antiphospholipid syndrome

Patients with antiphospholipid syndrome (APS) typically require lifelong warfarin anticoagulation following a thrombotic event due to a significant risk of recurrent thrombosis. Point of care testing (POCT) to monitor INR is discouraged in patients with APS as interactions between antiphospholipid antibodies and thromboplastin used for INR testing may influence results. Review of INR testing in 36 APS patients showed 87.2% of paired POCT and venous INRs (n = 94) having acceptable variation (≤0.5 difference), and high correlation (r = 0.9) excluding INRs ≥4.8. Six‐month TTR was comparable for APS patients using POCT (57.1% ± 24.8%) to those using venous INR monitoring (59.2% ± 23.2%) (p = 0.66). These results support POCT management of APS but requires further study.

Adverse Reaction to COVID-19 mRNA Vaccination in a Patient With VEXAS Syndrome

VEXAS (vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic) syndrome is a rare genetic disorder originating from a somatic mutation in the hematopoietic stem cells. This syndrome was first described in 2020 and carries many clinical features that other conditions cannot explain. Widespread autoinflammation is the primary process the disease presents, with high morbidity and mortality in those who show signs of bone marrow failure. Treatment is complex, and response to current therapies is poor. Long-term prognosis carries a mortality of 50%. In addition, the advancement of new-generation messenger ribonucleic acid (mRNA) vaccines raises concerns about their safety in this population since it could trigger a vaccine-related autoimmune response. This case describes the hospital course of a male in his 50s exhibiting an unexplained cutaneous reaction to an mRNA COVID-19 vaccine. He was later diagnosed with VEXAS syndrome based on symptoms presentation and diagnostic workup.

A Review of Cardiac Manifestations in Patients With Systemic Lupus Erythematosus and Antiphospholipid Syndrome With Focus on Endocarditis

Patients with autoimmune diseases such as systemic lupus erythematosus (SLE) or antiphospholipid syndrome (APS) are at a higher risk for adverse cardiovascular events associated with increased morbidity and mortality. The increased risk of these events is often associated with rheumatic heart disease (heart valve or mural endocardium damage from rheumatic fever) following microbial infection (i.e., untreated or under-treated streptococcal infection). In particular, the weakening of cardiac vasculature due to rheumatic heart disease makes such patients with autoimmune diseases more susceptible to endocarditis. Endocarditis can be caused by an infection (infective endocarditis) or inflammation tied to disease activity (non-bacterial thrombotic endocarditis [NBTE]). Infective endocarditis among patients with autoimmune diseases may result from exposure to pathogens during dental or surgical procedures. NBTE commonly occurs as a result of fibrin and platelet aggregation on the cardiac valves without bacterial infection. While diagnosis and management can vary based on underlying etiology, an interdisciplinary approach that includes prevention and management from dentists, cardiologists, rheumatologists, and primary care physicians is needed. In addition, increasing patient and physician education on risk factors and prevention strategies is much needed. This manuscript will review the pathophysiology of endocarditis, the association between SLE and APS and endocarditis risk, the diagnosis and management of these autoimmune diseases with a focus on the prevention of cardiovascular disease risk, and make recommendations for diagnostic and management approaches to improve care. 

Evaluation of Apixaban in Patients With Antiphospholipid Syndrome: A Case Series and Review of Literature

Several guidelines endorsed the indefinite use warfarin or heparin-containing products for acute venous thromboembolism (VTE) treatment and secondary prevention and discouraged the use of direct oral anticoagulants (DOAC) for patients diagnosed with antiphospholipid syndrome (APS). However, adequate anticoagulation despite warfarin therapy remains a challenge in APS patients. Using DOACs in APS patients is seen in clinical practice, despite the lack of evidence to support their use in this population. In this case series, we aim to evaluate the safety and effectiveness of apixaban use in nine patients with primary or secondary APS at King Abdulaziz Medical City (Riyadh, Saudi Arabia). All patients presented with APS and received apixaban with or without concomitant antiplatelet. Three patients had double positivity, and two patients had triple positivity of antiphospholipid antibodies (aPL). Some patients tolerated apixaban during the follow-up period, but recurrent VTE and stroke were reported in some of them. Bleeding complications were evident in some cases as well. In conclusion, warfarin remains the best choice to prevent VTE recurrence in patients with APS. On the other side, apixaban use in patients with APS may have some safety and effectiveness concerns evidenced by VTE recurrence and bleeding complications. The safety and effectiveness of utilizing apixaban in APS patients need to be assessed in well-controlled randomized trials.

Successful Treatment of Catastrophic Antiphospholipid Syndrome Using Rituximab: Case Report and Review of the Literature

BACKGROUND

Kidney involvement is a frequent complication of systemic lupus erythematosus (SLE) and kidney biopsy is essential in differentiating lupus nephritis (LN) from thrombotic microangiopathy (TMA) secondary to antiphospholipid autoantibodies (aPL). Association between antiphospholipid syndrome (APS) and acquired hemophilia due to inhibitors was very rarely described in SLE patients.

CASE PRESENTATION

We present the case of a 61-year-old male diagnosed with SLE who acquired deficiency of clotting factor VIII due to circulating inhibitors, admitted for acute kidney injury (AKI), microangiopathic hemolytic anemia, thrombocytopenia, and diplopia. Kidney biopsy showed TMA due to APS, but no signs of LN. Head computed tomography identified low dense areas in the white matter, suggesting small blood vessels' involvement. A diagnosis of probable catastrophic antiphospholipid syndrome (CAPS) was established and treatment with low molecular weight heparin, intravenous methylprednisolone, plasmapheresis, and rituximab was initiated, followed by resolution of AKI, diplopia, and TMA with complete depletion of CD19+B-lymphocytes (CD19+B-Ly) after one month. We further review the current knowledge regarding pathogenesis and management of CAPS in SLE patients.

CONCLUSIONS

Targeted therapy was possible after kidney biopsy, improving renal and general prognosis. CD19+B-Ly repopulation preceded biological relapse, so monitoring of CD19+B-Ly may serve as a tool to predict relapses and guide rituximab therapy.

Effect of statins on the prevention of recurrent thrombosis in thrombotic antiphospholipid syndrome

OBJECTIVE

To assess the effect of statins on the prevention of recurrent thrombosis in patients with thrombotic antiphospholipid syndrome (APS).

METHODS

This retrospective cohort study included 184 patients with thrombotic APS. The effect of statins on recurrent thrombosis was investigated in the total study population and in an inverse probability of treatment weighting (IPTW)-adjusted population. Multivariable and IPTW-adjusted Cox proportional hazard regression analyses were performed on the total study population and the IPTW-adjusted population, respectively, to estimate the hazard ratios (HRs) with 95% confidence intervals (95% CIs) for recurrent thrombosis, according to the use of statins.

RESULTS

Of the 184 patients, 103 (56.0%) received statins, while the other 81 (44.0%) did not. Recurrent thrombosis occurred in 22 (12.0%) patients during the mean observation period of 48.5 (±34.9) months. In the multivariable Cox regression analyses, the use of statins was associated with a lower risk of recurrent thrombosis: (1) model 1 adjusted for risk factors of arterial and venous thrombosis, HR 0.24, 95% CI 0.09-0.63, p= 0.004; (2) model 2 adjusted for the use of anticoagulants, antiplatelets, and hydroxychloroquine, HR 0.28, 95% CI 0.10-0.76, p= 0.012; and (3) model 3 adjusted for the antiphospholipid autoantibody profile, HR 0.26, 95% CI 0.10-0.67, p= 0.005. The IPTW-adjusted Cox regression analysis also showed a lower risk of recurrent thrombosis with the use of statins (HR 0.28; 95% CI, 0.12-0.65; p= 0.003).

CONCLUSION

Our data suggest that statins could be effective in reducing the risk of recurrent thrombosis in patients with thrombotic APS.

Management of patients with antiphospholipid antibodies: what to do in laboratory scenarios that do not fit the guidelines

Introduction: Some patients with positive antiphospholipid antibodies (aPL) have not been included in randomized clinical trials or observational registries and, therefore, information on their risk of obstetric or thrombotic recurrence and optimal treatment is scarce.Areas covered: In the present review, the existing evidence regarding the management of two laboratory scenarios not covered by the guidelines is presented: (1) patients with antiphospholipid syndrome (APS) clinical manifestations and aPL positivity not fulfilling APS laboratory criteria, and (2) the possibility of discontinuing anticoagulation in APS patients whose aPL become persistently negative.Expert opinion: Growing evidence suggests a role for low titers and 'non-criteria' aPL, especially in obstetric APS. Treatment is not formally recommended but might be considered according to the individual's risk profile. Regarding the question of whether or not to discontinue anticoagulants after the 'spontaneous' disappearance of aPL, there is no definite answer. Retrospective studies seem to suggest that withdrawal of anticoagulation could be safe in certain patients with APS, especially in those with a first provoked venous thrombosis and whose aPL became persistently negative during follow-up. Still, before the withdrawal can be recommended in routine clinical practice, multicenter and prospective studies are required to validate this hypothesis.

Entangling COVID-19 associated thrombosis into a secondary antiphospholipid antibody syndrome: Diagnostic and therapeutic perspectives (Review)

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a novel β coronavirus that is the etiological agent of the pandemic coronavirus disease 2019 (COVID-19) that at the time of writing (June 16, 2020) has infected almost 6 million people with some 450,000 deaths. These numbers are still rising daily. Most (some 80%) cases of COVID-19 infection are asymptomatic, a substantial number of cases (15%) require hospitalization and an additional fraction of patients (5%) need recovery in intensive care units. Mortality for COVID-19 infection appears to occur globally between 0.1 and 0.5% of infected patients although the frequency of lethality is significantly augmented in the elderly and in patients with other comorbidities. The development of acute respiratory distress syndrome and episodes of thromboembolism that may lead to disseminated intravascular coagulation (DIC) represent the primary causes of lethality during COVID-19 infection. Increasing evidence suggests that thrombotic diathesis is due to multiple derangements of the coagulation system including marked elevation of D-dimer that correlate negatively with survival. We propose here that the thromboembolic events and eventually the development of DIC provoked by SARS-CoV-2 infection may represent a secondary anti-phospholipid antibody syndrome (APS). We will apply both Baconian inductivism and Cartesian deductivism to prove that secondary APS is likely responsible for coagulopathy during the course of COVID-19 infection. Diagnostic and therapeutic implications of this are also discussed.