The relevance of "non-criteria" clinical manifestations of antiphospholipid syndrome: 14th International Congress on Antiphospholipid Antibodies Technical Task Force Report on Antiphospholipid Syndrome Clinical Features

Neurovascular Issues in Antiphospholipid Syndrome: Arterial Vasculopathy from Small to Large Vessels in a Neuroradiological Perspective

Antiphospholipid syndrome (APS) is an autoimmune prothrombotic condition characterized by venous thromboembolism, arterial thrombosis, and pregnancy morbidity. Among neurological manifestations, arterial thrombosis is only one of the possible associated clinical and neuroradiological features. The aim of this review is to address from a neurovascular point of view the multifaceted range of the arterial side of APS. A modern neurovascular approach was proposed, dividing the CNS involvement on the basis of the size of affected arteries, from large to small arteries, and corresponding clinical and neuroradiological issues. Both large-vessel and small-vessel involvement in APS were detailed, highlighting the limitations of the available literature in the attempt to derive some pathomechanisms. APS is a complex disease, and its neurological involvement appears multifaceted and not yet fully characterized, within and outside the diagnostic criteria. The involvement of intracranial large and small vessels appears poorly characterized, and the overlapping with the previously proposed inflammatory manifestations is consistent.

Performance validation of the 2023 American College of Rheumatology/European League Against Rheumatism antiphospholipid syndrome classification criteria in an antiphospholipid syndrome cohort

BACKGROUND

The 2023 American College of Rheumatology (ACR)/European League Against Rheumatism (EULAR) antiphospholipid syndrome (APS) classification criteria were developed with higher specificity but lower sensitivity compared with the 2006 Sydney revised classification criteria.

OBJECTIVES

To validate the performance of the 2023 ACR/EULAR APS classification criteria in a large Chinese APS cohort.

METHODS

This was a single-center cohort study. Inclusion criteria aligned with the entry criteria of 2023 criteria. APS classification by "expert consensus panel" served as the gold standard. Sensitivity and specificity were compared between the 2023 and 2006 criteria.

RESULTS

A total of 526 patients with a mean age of 38.55 ± 12.67 years were enrolled, of whom 366 (69.58%) were female and 182 (34.60%) had systemic lupus erythematosus (SLE). Among them, 407 (77.38%) patients were classified as APS by experts. The 2023 criteria demonstrated higher overall specificity than the 2006 criteria (0.983 vs 0.950), while sensitivity was relatively lower (0.818 vs 0.853). The sensitivity of the 2023 criteria improved for patients with SLE (0.860 vs 0.825), microvascular manifestations (0.867 vs 0.786), cardiac valve disease (0.903 vs 0.774), and thrombocytopenia (0.811 vs 0.790). Reduced sensitivity of the 2023 criteria was linked to the omission of certain microvascular manifestations, a stricter definition of pregnancy morbidity, and the exclusion of isolated thrombocytopenia and isolated IgM isotype antiphospholipid antibodies from meeting clinical and laboratory criteria, respectively.

CONCLUSION

The 2023 criteria offer higher overall specificity and improved sensitivity in specific patient subsets, such as those with SLE, microvascular manifestations, cardiac valve disease, and thrombocytopenia when compared with the 2006 criteria.

Acute peripartum pancreatitis complicating seronegative antiphospholipid antibody syndrome in pregnancy

Antiphospholipid antibody syndrome is an autoimmune condition with clinical manifestations of vascular thrombosis and adverse pregnancy outcomes including recurrent miscarriage, fetal loss, growth restriction and pre-eclampsia with persistent antiphospholipid antibodies on laboratory examination. Treatment is targeted at preventing recurrent thrombosis and improving pregnancy outcomes. Commonly, treatment includes aspirin and anticoagulation, however, newer immunomodulatory treatments may also improve outcomes. The case describes a patient with a history of multiple miscarriages and pregnancy losses, fetal growth restriction and pre-eclampsia, and pulmonary embolism. Because of her significant adverse pregnancy outcomes, she was treated with certolizumab with a successful delivery at 33 weeks and 6 days. She also developed acute pancreatitis in the postpartum period. This is a rare condition, affecting 1-14/10 000 births. The pancreatitis resolved with conservative management, and she had an uncomplicated interval cholecystectomy.

Heart valve disease in primary antiphospholipid syndrome

OBJECTIVES

APS-associated heart valve disease (HVD) is well described. Nonetheless, limited data exist on clinical parameters associated with the course of primary APS (pAPS) patients with HVD. The goal of this study was to assess clinical features and related outcomes in patients with APS-associated HVD.

METHODS

In this multicentre retrospective study, we identified 33 pAPS patients with HVD (pAPS-HVD group) and compared their clinical course with 128 pAPS patients with normal heart valves on echocardiography (pAPS-control group).

RESULTS

pAPS-HVD patients had more cerebrovascular events (56.3% vs 25%, P = 0.005) and livedo reticularis (24.2% vs 7.8%, P = 0.013) than pAPS-controls. Furthermore, catastrophic-APS (CAPS) (12.1% vs 2.4%, P = 0.034), recurrent thrombosis (33.3% vs 4.7%, P < 0.001) and need for advanced therapy (i.e. IVIG, plasmapheresis or rituximab) were more frequent in pAPS-HVD patients. Anti-β2-glycoprotein 1 IgG (84.8% vs 63.2%, P = 0.034), anti-cardiolipin IgG (90.9% vs 64.8%, P = 0.005) and triple positive aPL (75.8% vs 56.5%, P = 0.047) were commoner in pAPS-HVD patients vs pAPS-controls. Ten of the 33 patients with pAPS-HVD underwent valve surgery, which was associated with male gender, smoking, arterial limb ischaemia and livedo reticularis.

CONCLUSION

pAPS-HVD patients had a more severe APS clinical course including CAPS and thrombotic events as well as a specific serology, namely IgG isotype aPL antibodies and triple positivity. Our data suggest that pAPS-HVD represents a high-risk subgroup of APS patients.

Pattern of disease expression in SLE patients with antiphospholipid antibodies: data from Indian Systemic Lupus Erythematosus Inception cohort (INSPIRE)

Antiphospholipid antibodies (APLA) are present in one-third of systemic lupus erythematosus (SLE) patients, and they are associated with both criteria and non-criteria manifestations. We studied the prevalence, clinical associations, and impact on mortality of APLA in SLE patients from India. Among the Indian SLE inception cohort (INSPIRE), patients who had data on all five routinely performed APLAs [lupus anticoagulant (LA), IgG and IgM anticardiolipin antibody (aCL) and anti-β2-glycoprotein I(β2GPI)] at enrolment were selected. Patients were divided into four categories based on the presence/absence of APLA associated manifestations and presence/absence of the APLA viz SLE-APS, SLE-APLA, SLE: events but no APLA, and SLE: no events, no APLA (reference group). 1035 SLE patients at least 1 APLA antibody was detected in 372 (35.9%). LA was present in 206 (19.9%), aCL in 126 (12.2%) and β2-GPI in 178 (17.2%). There were 88 thrombotic events in 83 patients (8.0%); 73 (82.9%) being arterial; APLA positivity was present in 37 (44.6%) [AOR 1.70 (1.054, 2.76)]. SLE-APS patients were younger and had higher mortality [AOR 4.11 (1.51, 11.3)], neuropsychiatric and hematologic disease. SLE-APLA also had a higher mortality rate [AOR 2.94 (1.06, 8.22)] than the reference group. The mortality was highest in the subset of patients with thrombotic events in the presence of APLA [AOR 7.67 (1.25, 46.9)]. The mere presence of APLA also conferred higher mortality even in the absence of thrombotic events [AOR 3.51 (1.43, 8.63)]. Hematologic manifestations (36.1%) were the most common non-criteria-manifestation. One-third of SLE patients have APLA and its presence is associated with non-criteria hematologic manifestations, arterial thrombosis and higher mortality rate.

Thrombotic microangiopathy due to primary antiphospholipid syndrome: successful treatment with eculizumab

Antiphospholipid syndrome nephropathy includes a variety of histological lesions, including thrombotic microangiopathy, which is not included among the diagnostic criteria of antiphospholipid syndrome. Whereas in secondary antiphospholipid syndrome, e.g. to systemic lupus erythematosus, there is emerging evidence of a benefit from complement blockade with eculizumab, optimal treatment of primary antiphospholipid syndrome-associated thrombotic microangiopathy is currently unknown. We report the case of a 36-year-old male patient with primary antiphospholipid syndrome-associated thrombotic microangiopathy, presenting with a clinical picture of atypical hemolytic-uremic syndrome with frequent relapses, treated with eculizumab (four 900 mg weekly doses followed by 1200 mg fortnightly infusions) leading to resolution of hemolysis, long-term remission and partial kidney function recovery (peak serum creatinine 3.8 mg/dL, decreased and stabilized around 2.5 mg/dL) over a follow up period of over 2 years.

Stroke in a Patient With Antiphospholipid Syndrome

Antiphospholipid syndrome (APS) is characterized by the occurrence of thrombotic events and/or obstetric complications in the presence of antiphospholipid antibodies. It is considered one of the most common acquired thrombophilias. The presentation of stroke in patients with APS has been described in some studies; however, it is not frequent enough and there is not much information available regarding the indications for pharmacological thrombolysis and the safety of thrombolytic treatment. Likewise, current evidence does not describe contraindications to thrombolytic therapy in cases of this diagnosis, which makes management with fibrinolysis safe in these cases. A clinical case of stroke is presented in which pharmacological thrombolysis is performed with a successful outcome, without complications of angioedema or bleeding. Likewise, concerning the case, the main neurological manifestations associated with APS, especially in its association with stroke, are described.

The impact of antiphospholipid antibodies/antiphospholipid syndrome on systemic lupus erythematosus

aPLs are a major determinant of the increased cardiovascular risk in patients with SLE. They adversely affect clinical manifestations, damage accrual and prognosis. Apart from the antibodies included in the 2006 revised classification criteria for APS, other non-classical aPLs might help in identifying SLE patients at increased risk of thrombotic events. The best studied are IgA anti-β2-glycoprotein I, anti-domain I β2-glycoprotein I and aPS-PT. Major organ involvement includes kidney and neuropsychiatric systems. aPL/APS severely impacts pregnancy outcomes. Due to increased thrombotic risk, these patients require aggressive cardiovascular risk factor control. Primary prophylaxis is based on low-dose aspirin in high-risk patients. Warfarin is the gold-standard drug for secondary prophylaxis.

Epidemiology of antiphospholipid syndrome: macro- and microvascular manifestations

Antiphospholipid syndrome (APS) is a systemic autoimmune disease characterized by thrombotic and non-thrombotic macro- and microvascular manifestations and pregnancy complications in the setting of persistent antiphospholipid antibodies (aPL), namely anticardiolipin antibodies, anti-β2 glycoprotein-I antibodies and lupus anticoagulant. Four decades after its first description, APS prevalence and incidence are still not completely understood due to the limited number of well-designed, population-based multi-ethnic studies. Furthermore, despite decades of efforts to standardise aPL immunoassays, considerable intraassay and interlaboratory variances in aPL measures still exist. Large multicentre APS cohorts have shown a 10-year survival of ∼91% and the presence of catastrophic APS occurs in about 1% of the entire population, associated with a 50% mortality rate. Clinically, any organ can be affected in the context of large, medium or small vessel (artery and/or vein) thrombosis. Macrovascular thrombosis is the hallmark of the disease and veins are more frequently affected than arteries. Deep vein thrombosis/pulmonary embolism thromboembolic disease is the most common APS manifestation, while stroke and transient ischaemic attack are the most frequent arterial thrombosis events. Myocardial infarction can also occur and contributes to increased mortality in APS. A minority of patients present with thrombosis affecting the intraabdominal organs, including the liver, spleen, small and large bowel, and the kidneys. Microvascular thrombosis, including APS nephropathy, chronic skin ulcers and livedoid vasculopathy represent a diagnostic challenge requiring histologic confirmation. In this narrative review we summarize the available evidence on APS epidemiology, focusing on the description of the prevalence of macro- and microvascular manifestations of the disease.

Prevalence and adverse consequences of delayed diagnosis and misdiagnosis in thrombotic antiphospholipid syndrome. An observational cohort study and a review of the literature

OBIECTIVES

This study aims to prospectively evaluate the frequency and adverse consequences of diagnostic delay and misdiagnosis in a cohort of patients with thrombotic antiphospholipid syndrome (TAPS). In addition, a systematic review of the literature concerning the diagnostic delay and misdiagnosis of TAPS was carried out.

METHODS

Patient enrollment occurred between 1999 and 2022. The study group was formed by TAPS patients whose diagnosis was delayed and those who were misdiagnosed. The control group was made up of patients who were timely and correctly diagnosed with TAPS.

RESULTS

The literature review showed 42 misdiagnosed patients, 27 of them were in one retrospective cohort study and 15 in 13 case reports. One hundred sixty-one out of 189 patients (85.2%) received a timely, correct diagnosis of TAPS; 28 (14.8%) did not. The number of patients with diagnostic issues was significantly higher for the first period (1999-2010), and the number of patients with a correct diagnosis was significantly higher for the second one (2011-2022). When the clinical and laboratory characteristics of the patients with delayed diagnosis were compared with those with misdiagnosis, there was a significantly higher number of severe adverse consequences characterized by permanent disability or death in the latter group. The two most common types of misdiagnoses were systemic lupus erythematosus (6 cases, 46.1%) and cardiovascular diseases (4 cases, 30.8%).

CONCLUSIONS

The study demonstrates that although knowledge about TAPS has improved over time, diagnostic delays and errors remains to be addressed as they are strongly associated to adverse consequences. Key Points •Although knowledge of thrombotic antiphospholipid syndrome has improved over time, it is still limited. •Diagnostic delay and misdiagnosis are still an important issue that remains to be addressed as they are strongly associated to adverse consequences. •The three more frequent misdiagnoses are multiple sclerosis, systemic lupus erythematosus and cardiovascular diseases.

Clinical features, risk factors, and outcomes of diffuse alveolar hemorrhage in antiphospholipid syndrome: A mixed-method approach combining a multicenter cohort with a systematic literature review

BACKGROUND

Antiphospholipid syndrome (APS) is a systemic autoimmune disease clinically associated with thrombotic and obstetric events. Additional manifestations have been associated with APS, like diffuse alveolar hemorrhage (DAH). We aimed to summarize all the evidence available to describe the presenting clinical features, their prognostic factors, and short- and long-term outcomes.

METHODS

We performed a mixed-method approach combining a multicenter cohort with a systematic literature review (SLR) of patients with incident APS-associated DAH. We described their clinical features, treatments, prognostic factors, and outcomes (relapse, mortality, and requirement of mechanical ventilation [MV]). Kaplan-Meier methods were used to estimate relapse and mortality rates, and Cox and logistic regression models were used to assess the factors associated as appropriate.

RESULTS

We included 219 patients with incident APS-associated DAH (61 from Mayo Clinic and 158 from SLR). The median age was 39.5 years, 51% were female, 29% had systemic lupus erythematosus, and 34% presented with catastrophic APS (CAPS). 74% of patients had a history of thrombotic events, and 26% of women had a history of pregnancy morbidity; half of the patients had a history of thrombocytopenia, and a third had valvulopathy. Before DAH, 55% of the patients were anticoagulated. At DAH onset, 65% of patients presented hemoptysis. The relapse rate was 47% at six months and 52% at one year. Triple positivity (HR 4.22, 95% CI 1.14-15.59) was associated with relapse at six months. The estimated mortality at one and five years was 30.3% and 45.8%. Factors associated with mortality were severe thrombocytopenia (< 50 K/μL) (HR 3.10, 95% CI 1.39-6.92), valve vegetations (HR 3.22, 95% CI 1.14-9.07), CAPS (HR 3.80, 95% CI 1.84-7.87), and requirement of MV (HR 2.22, 95% CI 1.03-4.80). Forty-two percent of patients required MV on the incident DAH episode. Patients presenting with severe thrombocytopenia (OR 6.42, 95% CI 1.77-23.30) or CAPS (OR 4.30, 95% CI 1.65-11.16) were more likely to require MV.

CONCLUSION

APS-associated DAH is associated with high morbidity and mortality, particularly when presenting with triple positivity, thrombocytopenia, valvular involvement, and CAPS.

Assessing disease activity and damage in antiphospholipid syndrome

Antiphospholipid syndrome (APS) has been characterized by a variety of vascular and pregnancy manifestations related to an interplay between thrombotic and inflammatory mechanisms, a progressive accrual of irreversible organ damage and increased morbidity and mortality rates, supporting a high need of optimal treatment approach. The lack of standardized outcome measures is a significant barrier in the design of clinical studies in APS. Disease activity (in principle reversible) and its distinction from disease damage (in principle irreversible) needs to be evaluated by validated scores for use in clinical trials but also in daily clinical practice in APS. A disease damage score in APS, the DIAPS score, has been developed and validated in external cohorts. The development of a disease activity score that will provide an accurate and reproducible rating of each disease domain, can help clinicians and researchers to comprehensively assess the activity of disease and the response to treatment, in an attempt to prevent future damage.

Antiphospholipid Syndrome and Kidney Involvement

BACKGROUND

Antiphospholipid syndrome (APS) is an autoimmune disease characterized by the development of autoantibodies and the impairment of the coagulation system. Knowledge about this syndrome is increasing over time, but kidney involvement, especially APS nephropathy, still represents a challenge for physicians.

SUMMARY

A "two hit" model has been hypothesized to explain APS pathophysiology, and the role played by some factors, such as the complement system, is becoming more and more clear. From a clinical point of view, along with thrombosis in any site and/or obstetric morbidities, that are the hallmarks of APS, a constellation of several other clinical symptoms is related to APS. These symptoms alone are not sufficient to fulfill Sydney criteria for APS and this could potentially lead to omitting some diagnoses. The mainstay of management of APS is antithrombotic therapy, but there are expectations for new drugs that regulate the immune system. APS could affect the kidneys in many ways and among them, APS nephropathy is an intriguing entity that has been overlooked in recent years. Novel studies on APS nephropathy are lacking.

KEY MESSAGES

In this review, we discuss what we currently know about APS and its relationship with the kidney, with an eye toward the future perspectives. Multicenter studies on APS nephropathy are necessary in order to develop targeted therapies.

Primary and secondary immune thrombocytopenia (ITP): Time for a rethink

There are not many publications that provide a holistic view of the management of primary and secondary ITP as a whole, reflecting the similarities and differences between the two. Given the lack of major clinical trials, we believe that comprehensive reviews are much needed to guide the diagnosis and treatment of ITP today. Therefore, our review addresses the contemporary diagnosis and treatment of ITP in adult patients. With respect to primary ITP we especially focus on establishing the management of ITP based on the different and successive lines of treatment. Life-threatening situations, "bridge therapy" to surgery or invasive procedures and refractory ITP are also comprehensively reviewed here. Secondary ITP is studied according to its pathogenesis by establishing three major differential groups: Immune Thrombocytopenia due to Central Defects, Immune Thrombocytopenia due to Blocked Differentiation and Immune Thrombocytopenia due to Defective Peripheral Immune Response. Here we provide an up-to-date snapshot of the current diagnosis and treatment of ITP, including a special interest in addressing rare causes of this disease in our daily clinical practice. The target population of this review is adult patients only and the target audience is medical professionals.

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.

Oxidative Stress as a Regulatory Checkpoint in the Production of Antiphospholipid Autoantibodies: The Protective Role of NRF2 Pathway

Oxidative stress is a well-known hallmark of Antiphospholipid Antibody Syndrome (APS), a systemic autoimmune disease characterized by arterial and venous thrombosis and/or pregnancy morbidity. Oxidative stress may affect various signaling pathways and biological processes, promoting dysfunctional immune responses and inflammation, inducing apoptosis, deregulating autophagy and impairing mitochondrial function. The chronic oxidative stress and the dysregulation of the immune system leads to the loss of tolerance, which drives autoantibody production and inflammation with the development of endothelial dysfunction. In particular, anti-phospholipid antibodies (aPL), which target phospholipids and/or phospholipid binding proteins, mainly β-glycoprotein I (β-GPI), play a functional role in the cell signal transduction pathway(s), thus contributing to oxidative stress and thrombotic events. An oxidation-antioxidant imbalance may be detected in the blood of patients with APS as a reflection of disease progression. This review focuses on functional evidence highlighting the role of oxidative stress in the initiation and progression of APS. The protective role of food supplements and Nuclear Factor Erythroid 2-Related Factor 2 (NRF2) activators in APS patients will be summarized to point out the potential of these therapeutic approaches to reduce APS-related clinical complications.

Anti-Phosphatidylserine, Anti-Prothrombin, and Anti-Annexin V Autoantibodies in Antiphospholipid Syndrome: A Real-Life Study

The antiphospholipid antibodies (aPL) increase the risk of developing thrombotic events and may coexist with a variety of autoimmune diseases. They can be detected chronically or temporarily in patients with infectious diseases, during drug therapy, or in cases of cancer. A thrombotic event with aPL detection is known as antiphospholipid syndrome (APS) and the diagnostic criteria include the presence of lupus anticoagulant (LA), anticardiolipin (aCL) and β2-glycoprotein-1(aβ2GPI) antibodies. Other autoantigens recognized in APS are phosphatidylserine (aPS), prothrombin (aPT) and Annexin-5 (aA5). This real life study aimed to explore the connections between laboratory criteria and the prevalence of "non-criteria aPL" in APS. This study followed 300 patients with thrombosis and employed two phospholipid sensitivity assays for LA detection, chemiluminescence assays for aCL and aβ2GPI and enzyme-linked immunoassays for aPS, aPT and aA5. A significant association was found between aPS and aCL (r = 0.76) as well as aβ2GPI (r = 0.77), while the association with LA was less significant (r = 0.33). The results of the aPT and aA5 test did not correlate with criteria-antiphospholipid antibodies (r < 0.30). Since the risk of thrombotic complications increases with the intensity and the number of positive autoantibodies, measuring aPT and aA5 autoantibodies may be useful, particularly in aCL/aβ2GPI-negative patients or in cases of isolated LA positivity.

Heart Valve Surgery in Antiphospholipid Syndrome Patients—Morbidity and Mortality

Objectives: To assess valve surgery outcomes in antiphospholipid syndrome (APS). Methods: A retrospective study assessing complications and mortality rate and possible factors associated with adverse outcomes of APS patients undergoing valve surgery in two tertiary medical centers. Results: Twenty-six APS patients (median age at surgery 47.5 years) who underwent valve surgery were detected, of whom 11 (42.3%) had secondary APS. The mitral valve was most commonly involved (n = 15, 57.7%). A valve replacement was performed in 24 operations (92.3%), 16 of which (66.7%) were mechanical valves. Fourteen (53.8%) patients sustained severe complications, and four of them died. The presence of mitral regurgitation (MR) was associated with severe complications and mortality (odds ratio (95% confidence interval) 12.5 (1.85–84.442), p = 0.008, for complications. All deceased patients had MR (p = 0.033). The presence of Libman-Sacks endocarditis (LSE) (7.333 (1.272–42.294), p = 0.045), low C3 (6.667 (1.047–42.431), p = 0.05) and higher perioperative prednisone doses (15 ± 21.89 vs. 1.36 ± 3.23 mg/day, p = 0.046) were also associated with complications. A lower glomerular filtration rate (GFR) was associated with mortality (30.75 ± 19.47 vs. 70.68 ± 34.44 mL/min, p = 0.038). Conclusions: Significant morbidity and mortality were observed among APS patients undergoing valve surgery. MR was associated with mortality and complications. LSE, low complement and higher doses of corticosteroids were associated with complications, while a low GFR was associated with mortality.

Brazilian society of rheumatology methodological guide for the development of evidence-based clinical guidelines in rheumatology

Clinical practice guidelines (CPG) are developed to align standards of health care around the world, aiming to reduce the incidence of misconducts and enabling more effective use of health resources. Considering the complexity, cost, and time involved in formulating CPG, strategies should be used to facilitate and guide authors through each step of this process. The main objective of this document is to present a methodological guide prepared by the Epidemiology Committee of the Brazilian Society of Rheumatology for the elaboration of CPG in rheumatology. Through an extensive review of the literature, this study compiles the main practical recommendations regarding the following steps of CPG drafting: distribution of working groups, development of the research question, search, identification and selection of relevant studies, evidence synthesis and quality assessment of the body of evidence, the Delphi methodology for consensus achievement, presentation and dissemination of the recommendations, CPG quality assessment and updating. This methodological guide serves as an important tool for rheumatologists to develop reliable and high-quality CPG, standardizing clinical practices worldwide.

Patients with laboratory criteria of anti-phospholipid syndrome and 'non-criteria' manifestations: a multicenter cohort

OBJECTIVES

Patients with laboratory criteria for anti-phospholipid syndrome (APS) but presenting only 'non-criteria' clinical manifestations are scarcely characterized in the literature. We aimed to analyse a cohort of these patients regarding the most prevalent manifestations, antibody profile, and treatments, while establishing a comparison with definite APS patients.

METHOD

A retrospective analysis was conducted of individuals fulfilling APS laboratory criteria assessed in two tertiary European hospitals between 2005 and 2020. Patients without clinical criteria but with non-criteria manifestations (termed 'clinical non-criteria') and age-/gender-matched controls were included.

RESULTS

Altogether, 75 clinical non-criteria patients were analysed, with haematological (thrombocytopenia, haemolytic anaemia) and 'mild' neurological manifestations (white-matter lesions, migraine) as the most prevalent non-obstetric involvements. These patients displayed more thrombocytopenia [odds ratio (OR) = 3.6, 95% confidence interval (CI) 1.7-7.6; p = 0.001] than controls with APS, but severe manifestations, such as valvular heart disease (p < 0.001), livedoid vasculopathy, seizures, chorea, transverse myelitis, bone necrosis, and alveolar haemorrhage, occurred only in definite APS patients. Corticosteroids were required by 40% of patients with thrombocytopenia. Manifestations in anticoagulated patients included white-matter lesions, nephropathy, superficial vein thrombosis, amaurosis fugax, and livedoid vasculopathy. Suspicion of progression towards systemic lupus erythematosus (SLE) occurred in 19% of non-SLE individuals.

CONCLUSION

'Clinical non-criteria' patients displayed significant treatment use, predominantly haematological involvement, and less severe manifestations than definite APS controls. Some patients may additionally progress to future SLE. The impact of certain manifestations flags them as potential future contributors to classifying individuals as definite APS.

Extra-criteria antiphospholipid antibodies in patients with small vessel brain lesions and clinical manifestations associated with antiphospholipid syndrome

OBJECTIVES

Neurological manifestations compatible with small vessel brain lesions (SVBL), such as migraine, cognitive impairment, seizures, and transverse myelitis, may be related to antiphospholipid syndrome (APS) and patients could need APS therapies even though they do not fit into thrombosis or obstetric morbidity. Furthermore, extra-criteria antiphospholipid antibodies (aPL) provide an increase in sensitivity in patients with clinical manifestations related to APS but negative for IgG/IgM anticardiolipin (aCL), anti-β2 glycoprotein I (aβ2GPI), and lupus anticoagulant, which are the antibodies included in the classification criteria for APS.

METHODS

We determined extra-criteria aPL in 65 SVBL patients with neurological traits and Magnetic Resonance Imaging suggestive of APS but negative for APS classification criteria, 47 of whom were prospectively followed and tested over three years. A group of 95 patients with autoimmune diseases (AD) but without clinical traits of APS was also studied.

RESULTS

A persistent presence of extra-criteria aPL was detected in 27.7% of patients: 12.77% IgM anti- prothrombin (PT), 6.38% IgG anti-PT, 6.38% IgM anti-phosphatidylethanolamine (PE), 4.26% IgA aβ2GPI, 2.13% IgG anti-phosphatidylserine/prothrombin (PS/PT) and 2.13% IgM anti-PS/PT. There was a tendency towards a higher prevalence of these aPL in SVBL patients than in AD - especially for IgA aβ2GPI - and a lack of IgG aPS/PT positivity in the AD group. We found no SVBL patient positive for IgA aCL, IgG anti-PE, annexin V, or aβ2GPI domain I.

CONCLUSIONS

Extra-criteria aPL can improve sensitivity for APS diagnosis in patients with SVBL, especially IgA aβ2GPI and IgG anti-PS/PT antibodies.

An advanced understanding of the heterogeneous clinical features of "non-criteria" obstetric antiphospholipid syndrome: Two case reports and a literature review

Antiphospholipid syndrome (APS) is an acquired autoimmune disorder characterized by recurrent venous and/or arterial thrombosis and/or pregnancy complications, in the presence of elevated antiphospholipid (aPL) antibodies. APS in pregnant women is referred to as "obstetrical" APS (OAPS). The diagnosis of definite OAPS requires the presence of one or more typical clinical criteria and persistent aPL antibodies at least 12 weeks apart. However, the classification criteria for OAPS have generated wide discussion, with a growing impression that certain patients not fully meeting these criteria might be inappropriately excluded from the classification, which is known as "non-criteria" OAPS. We present here two unique cases of potentially lethal "non-criteria" OAPS, complicating severe preeclampsia, fetal growth restriction (FGR), liver rupture, preterm birth, refractory recurrent miscarriages, or even stillbirth. We further share our diagnostic search and analysis, treatment adjustment, and prognosis for this unusual antenatal event. We will also present a short review of an advanced understanding of the pathogenetic mechanisms of this disease, heterogeneous clinical features, and potential significance.

Clinical phenotype, treatment strategy and pregnancy outcome of non-criteria obstetric antiphospholipid syndrome

PROBLEM

To illustrate the clinical features, treatment strategy, and pregnancy outcome of patients with obstetric antiphospholipid syndrome (OAPS), non-criteria obstetric antiphospholipid syndrome (NC-OAPS) METHOD OF STUDY: A single-center nested case-control study was designed. Patients with a diagnosis of OAPS and NC-OAPS were enrolled. The medical history, coagulation status, and antibody profile data were collected. Patients were given standard anticoagulation therapy with or without glucocorticoids (GC) and/or hydroxychloroquine (HCQ) during pregnancy and were observed for their pregnancy outcome.

RESULTS

A total of 47 patients with OAPS and 120 patients with NC-OAPS were finally included, of whom 55 patients met the clinical criteria (subgroup C) and 65 met the laboratory criteria (subgroup L). Pregnancy morbidity showed significant differences: gravida, pregnancy loss in OAPS versus NC-OAPS. The coagulation function was not significantly different between OAPS and NC-OAPS groups, while TT and FIB were significantly higher in the subgroup C. Thromboelastography (TEG) results showed a significantly lower ANGEL in the NC-OAPS group, a higher ANGEL and lower EPL, LY30 in the subgroup L. No differences between groups were observed in treatment strategy. The pregnancy outcomes were not significantly different between NC-OAPS and OAPS groups.

CONCLUSIONS

Clinical and laboratory differences were found between OAPS and NC-OAPS groups in this study. Patients in different subgroups of NC-OAPS could be identified with different clinical phenotypes. A relatively hypercoagulable status existed in the OAPS group compared to NC-OAPS, and also in the subgroup L.

Severe Libman-Sacks endocarditis complicating antiphospholipid syndrome: a retrospective analysis of 23 operated cases

OBJECTIVE

Data on severe heart valve disease (HVD), including Libman-Sacks endocarditis, associated with SLE and/or APS requiring valvular surgery are scarce. We thus conducted a retrospective study, aimed at describing and clarifying clinical, laboratory, echocardiographic, histopathological and evolutional features of SLE and/or APS patients with severe associated-HVD.

METHODS

An observational retrospective multicentric analysis of 23 adults with SLE and/or APS and HVD between 1996 and 2019 and available histopathological report evaluating long-term follow-up.

RESULTS

Twenty-three individuals (20 females, median age 37 [range 17-76] years) were included. All had APS (thrombotic in 22, with an arterial phenotype in 15 and with catastrophic APS [CAPS] in six), and 11 (47%) had SLE. Systemic underlying disease had been diagnosed prior to HVD in 12 (52%). In 10 patients (43%), HVD was complicated by cerebral stroke prior to surgery. Twenty patients (87%) had only one pathological valve, the mitral valve in 18 patients (78%). Valvular thickening (n = 19) and valvular regurgitation (n = 19) were the most frequently reported lesions. Fifteen (62%) patients underwent mechanical valve replacement, six (26%) conservative valve repair (five were later re-operated after a median time of 1 [0-4] year), and two (9%) underwent biological valve replacement. Nine patients (39%) presented early-onset post-operative complications, including three CAPS immediately after surgery and one death. After surgery, 18 patients (78%) had normal postoperative valvular function, but almost half of the patients (43%) had post-operative neurological sequelae (median follow-up of 6 [2-20] years).

CONCLUSION

Severe HVD leading to surgery was strongly associated with thrombotic APS, especially arterial phenotypes. Half of the reported patients presented cerebral stroke complicating the HVD. Valvular surgery carried a significant risk of CAPS.

B-Cells and BAFF in Primary Antiphospholipid Syndrome, Targets for Therapy?

Primary antiphospholipid syndrome (PAPS) is a systemic autoimmune disease characterized by thrombosis, pregnancy morbidity, and the presence of antiphospholipid antibodies (aPL). Anticoagulants form the mainstay of treatment in PAPS. A growing number of studies suggest a previously underappreciated role of the immune system in the pathophysiology of PAPS. Although B-cells are strongly implicated in the pathophysiology of other autoimmune diseases such as systemic lupus erythematosus (SLE), little is known about the role of B-cells in PAPS. Shifts in B-cell subsets including increases in plasmablasts and higher levels of BAFF are present in patients with PAPS. However, while treatment with rituximab and belimumab may ameliorate thrombotic and non-thrombotic manifestations of PAPS, these treatments do not reduce aPL serum levels, suggesting that B-cells contribute to the pathophysiology of APS beyond the production of autoantibodies.

[Clinical significance of oxidized low-density lipoprotein antibody in antiphospholipid syndrome]

OBJECTIVE

To investigate the significance and distribution of oxidized low-density lipoprotein antibodies (ox-LDL-Ab) in patients with antiphospholipid syndrome (APS).

METHODS

In this study, 334 patients who were hospitalized in the Department of Rheumatology and Immunology, Peking University People's Hospital were included. There were 162 APS patients, 122 patients with other autoimmune diseases without thrombosis or obstetric disease as disease control and 50 healthy controls. The clinical data and laboratory indicators were retrospectively collected. The ox-LDL-Ab, anticardiolipin (aCL) IgG/IgA/IgM, and anti-β2-glycoprotein Ⅰ (aβ2GPI) IgG/IgA/IgM were detected by enzyme-linked immunosorbent assay (ELISA). The relationship between ox-LDL-Ab and clinical and laboratory parameters were analyzed by SPSS 27.0.

RESULTS

In APS group, 60.5% of patients had thrombosis, 48.1% had pregnancy morbidity, 34.0% had thrombocytopenia. The positive rates of aCL, aβ2GPI and lupus anticoagulant (LAC) were 17.9%, 34.6%, and 46.9%, respectively. The ox-LDL-Ab titers and positive rate in APS group were higher than that in healthy controls [titers: 40.8 (25.4-66.0) U/mL vs. 24.1 (12.3-36.5) U/mL, P=0.001; positive rate: 67.3% vs. 36.0%, P=0.001]. The diffe-rences in titers and positive rate of ox-LDL-Ab between APS patients and disease controls were not statistically significant [titers: 40.8 (25.4-66.0) U/mL vs. 35.9 (24.2-53.1) U/mL, P=0.118; positive rate: 67.3% vs. 61.5%, P=0.318]. The area under curve (AUC) for aβ2GPI, aCL, and ox-LDL-Ab were 0.745 (95%CI: 0.692-0.797), 0.666 (95%CI: 0.608-0.724), 0.609 (95%CI: 0.549-0.669), respectively. The Youden's index was 0.388, 0.269, and 0.132, respectively. The AUC for ox-LDL-Ab in seronegative APS patients was 0.562 (95%CI: 0.480-0.645). The sensitivity and specificity of ox-LDL-Ab in seronegative APS patients were 63.9% and 47.0%, respectively, and the Youden's index was 0.109. The ox-LDL-Ab positive group had higher positive rate of aβ2GPI (42.2% vs. 18.9%, P=0.003) and aCL (22.9% vs. 7.5%, P=0.017) than the ox-LDL-Ab negative group. There was no correlation between ox-LDL-Ab and thrombosis, coronary artery disease, pregnancy morbidity, hyperlipidemia, hypocomplementemia, and LAC positivity.

CONCLUSION

Ox-LDL-Ab was correlated with aCL and aβ2GPI, and no association were observed between ox-LDL-Ab and thrombosis, coronary artery disease, and pregnancy morbidity.

Analysis of Serbian Primary Antiphospholipid Syndrome Patients Confirmed a Strong Association Between Livedo Reticularis and Arterial Thrombosis: A National Cross-Sectional Cohort Study

BACKGROUND

Antiphospholipid syndrome (APS) is characterized by antiphospholipid antibodies (aPLs) associated with thrombosis (arterial and/or venous) and/or obstetrical manifestations. However, various manifestations, which are considered to be noncriteria manifestations, are frequently found in APS.

AIM

The purpose of this study was to evaluate whether noncriteria manifestations may be found more frequently in subjects with thrombotic and/or obstetrical APS ("criteria" manifestations) in a population of patients with primary APS (PAPS). This study presents the results from our national cohort.

PATIENTS AND METHODS

This is a cross-sectional study of 360 PAPS patients. Data regarding the presence of thrombocytopenia, livedo reticularis, chorea, and valvulopathy were analyzed. The aPL analysis included the detection of anticardiolipin antibodies (aCLs: immunoglobulin G [IgG]/IgM), anti-β 2 glycoprotein I (IgG/IgM), and lupus anticoagulant positivity.

RESULTS

In our cohort, livedo reticularis was significantly related to arterial thromboses in the same way as valvular manifestations (valvular vegetations and valvular thickening and dysfunction not related to age) ( p = 0.0001, p = 0.013, respectively). Age was strongly related to all the noncriteria manifestations analyzed. Thrombocytopenia was significantly related to β 2 glycoprotein I IgG and lupus anticoagulant positivity ( p = 0.043, p = 0.030, respectively), as well as to double and triple aPL positivity ( p = 0.041, p = 0.013 respectively). Moreover, in a multivariate model, livedo reticularis was strongly and independently related to arterial thrombosis in our cohort (odds ratio, 2.010; confidence interval, 1.229-3.288; p = 0.005).

CONCLUSION

This cross-sectional analysis of a large cohort of Serbian PAPS patients confirmed a strong relationship between livedo reticularis and arterial thrombosis, suggesting a more cautious approach regarding the presence of noncriteria manifestations, especially livedo reticularis, in APS.

Circulating immune-complexes of IgG/IgM bound to B2-glycoprotein-I associated with complement consumption and thrombocytopenia in antiphospholipid syndrome

Background

Antiphospholipid syndrome (APS) is a multisystemic autoimmune disorder characterized by thrombotic events and/or gestational morbidity in patients with antiphospholipid antibodies (aPL). In a previous single center study, APS-related clinical manifestations that were not included in the classification criteria (livedo reticularis, thrombocytopenia, leukopenia) were associated with the presence of circulating immune-complexes (CIC) formed by beta-2-glycoprotein-I (B2GP1) and anti-B2GP1 antibodies (B2-CIC). We have performed a multicenter study on APS features associated with the presence of B2-CIC.

Methods

A multicenter, cross-sectional and observational study was conducted on 303 patients recruited from six European hospitals who fulfilled APS classification criteria: 165 patients had primary APS and 138 APS associated with other systemic autoimmune diseases (mainly systemic lupus erythematosus, N=112). Prevalence of B2-CIC (IgG/IgM isotypes) and its association with clinical manifestations and biomarkers related to the disease activity were evaluated.

Results

B2-CIC prevalence in APS patients was 39.3%. B2-CIC-positive patients with thrombotic APS presented a higher incidence of thrombocytopenia (OR: 2.32, p=0.007), heart valve thickening and dysfunction (OR: 9.06, p=0.015) and triple aPL positivity (OR: 1.83, p=0.027), as well as lower levels of C3, C4 and platelets (p-values: <0.001, <0.001 and 0.001) compared to B2-CIC-negative patients. B2-CIC of IgM isotype were significantly more prevalent in gestational than thrombotic APS.

Conclusions

Patients with thrombotic events and positive for B2-CIC had lower platelet count and complement levels than those who were negative, suggesting a greater degree of platelet activation.

Non-criteria antiphospholipid antibodies and pediatric rheumatic disease: a case series

BACKGROUND

Non-criteria antiphospholipid antibodies (NC-aPL) are a relatively undefined subgroup of antiphospholipid antibodies (aPL). Knowledge about NC-aPL in adults is limited and even less is known in pediatric patients. Routine tests for antiphospholipid syndrome (APS)-a clinical state marked by the presence of aPL in association with vascular thrombosis-usually include lupus anticoagulant (LAC), anti-cardiolipin (aCL) and -beta-2 glycoprotein I (aβ2GPI). LAC is a functional screen for prothrombotic aPL, while the latter tests identify specific autoantibodies. Specific targets of NC-aPL include, but are not limited to, phosphatidylethanolamine, phosphatidylserine, and prothrombin.

PRESENTATION OF CASES

We present single-center data from eight pediatric patients with NC-aPL identified during a three-year period. All patients had presenting features raising suspicion for APS. Most patients were female with a primary rheumatic disease. One patient had a stroke. Another patient had alveolar hemorrhage and pulmonary hypertension. Raynaud's phenomenon, rashes involving distal extremities, and headaches were common. Most patients had a positive LAC, yet their routine aPL tests were negative, prompting testing for NC-aPL.

CONCLUSIONS

Our findings suggest NC-aPL are associated with typical signs and symptoms of APS in pediatric patients. Pediatricians and pediatric subspecialists should consider NC-aPL when clinical suspicion is high and routine aPL tests are negative, particularly when LAC is positive. While guidelines for NC-aPL do not yet exist for children or adults, these autoantibodies have pathogenic potential. Actionable items could include evaluation for the presence of other (primary) rheumatic diseases, and consultation with hematologists and/or obstetricians regarding anticoagulation/platelet inhibition and thrombosis education. Future guidelines regarding NC-aPL will only be generated by gathering more data, ideally prospectively.

Comparison of non-criteria antiphospholipid syndrome with definite antiphospholipid syndrome: A systematic review

Objectives

Patients with laboratory or clinical manifestations suggestive of antiphospholipid syndrome (APS) but not fulfilling the classification criteria constitute a clinical challenge. This study aims to compare non-criteria APS (NC-APS) with definite APS in terms of clinical manifestations, therapies, and outcomes.

Methods

A systematic review of observational studies comparing definite and NC-APS was performed searching four electronic databases. Data on clinical manifestations, therapies and clinical outcomes was extracted.

Results

Sixteen studies, assessing a total of 3,798 participants, were included. Seven out of 10 studies found no significant difference in the prevalence of arterial or venous thrombosis between definite and NC-APS, with two studies on seronegative APS also finding no difference in thrombosis recurrence. Seven out of 12 studies found no significant difference in the prevalence of obstetric manifestations between groups, with the remaining exhibiting conflicting results. In 9 studies comparing treatment frequency in obstetric patients, all but one described similar treatment frequency, with the percentage of NC-APS treated during pregnancy ranging from 26% to 100%. In 10 studies comparing pregnancy outcomes of NC-APS versus definite APS, 7 found similar successful pregnancies/live births. Additionally, 5 studies described improvement of live births in both groups with treatment, with three signalling aspirin monotherapy as efficacious as combination therapy in NC-APS.

Conclusion

This review hints at an absence of marked differences in most evaluated parameters between definite and NC-APS, emphasizing the value of a more active follow-up of these patients. The low-quality available evidence highlights the need for well-defined NC-APS populations in future studies.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero, identifier CRD42020210674.

Renal and vascular outcomes in patients with isolated antiphospholipid syndrome nephropathy

BACKGROUND

Antiphospholipid syndrome (APS) nephropathy (APSN) is a rare pattern with specific features resulting from microvascular lesions. The prognosis of APSN, outside of lupus nephritis, is unknown. The aim of this study was to describe the renal, vascular and overall outcomes of patients with APSN.

METHODS

Retrospective multicenter study of patients with antiphospholipid antibodies (aPL) associated with histological APSN lesions and no other nephropathy, identified through a national call for medical records. End-stage renal disease (ESRD)-free survival, thrombosis recurrence-free survival and overall survival were assessed.

RESULTS

Thirty patients were included (19 women) with a median age of 40 years (34-52 years). Fifteen patients had APS, 26/28 had lupus anticoagulant, and 15/26 had triple positivity for aPL. Median eGFR was 50 (31-60) mL/min/1.73 m². Glomerular thrombotic microangiopathy was found in 12/24 cases, fibrous intimal hyperplasia in 12/22 cases and focal cortical atrophy in 17/29 cases. Nineteen patients had moderate to severe interstitial fibrosis (>25%). Six patients developed ESRD at a median follow-up of 6.2 (1.8-9.1) years. The ESRD-free survival rates at 5 and 10 years were 80.0% (95% CI 57.6%-91.4%) and 72.7% (95% CI, 46.9%-87.4%) respectively. None of the histological factors considered was significantly associated with a decrease in eGFR at 12 months. Thrombosis recurrence-free survival was 77.8% (95% CI 48.2%-91.6%) at 10 years. Overall survival was 94% at 10 years (95% CI 65.0%-99.2%).

CONCLUSIONS

The renal prognosis of isolated APSN is poor. The severe fibrotic lesions observed are suggestive of late diagnosis.

Clinical characteristics and prognosis of patients with antiphospholipid antibodies based on cluster analysis: an 8-year cohort study

Background

Antiphospholipid syndrome (APS) is an autoimmune disease characterized by persistent antiphospholipid antibodies (aPLs) positivity with a wide manifestation spectrum. A risk stratification is needed for management guidance and prognosis assessment. We aimed to identify phenotypes among aPL-positive patients and assess the prognosis of each phenotype.

Methods

This was a single-center, prospective cohort study of aPL-positive patients presented to Peking Union Medical College Hospital from 2012 to 2020. Demographic characteristics, aPL-related manifestations, cardiovascular risk factors, and antibodies profiles were recorded. The primary endpoint was defined as a combination of newly onset thrombosis, major bleeding events, non-criteria manifestations, and all-cause death. Hierarchical cluster analysis and Kaplan-Meier survival analysis were performed.

Results

Four clusters among 383 patients (70.2% female; mean age 37.7 years) were identified. Cluster 1 (n = 138): patients with systemic lupus erythematosus (SLE) and non-criteria manifestations; cluster 2 (n = 112): patients with multiple cardiovascular risk factors; cluster 3 (n = 83): female patients with obstetric morbidity; cluster 4 (n = 50): patients with isolated lupus anticoagulant (LA) positivity.

Non-criteria manifestations were found aggregated with SLE from cluster analysis of variables. Cluster 3 showed the best outcome, while cluster 2 suffered highest frenquency of newly onset arterial thrombosis.

Conclusions

We identified 4 clinical phenotypes of aPL-positive patients. Non-criteria manifestations may indicate underlying SLE, for which immunosuppressive therapy besides anticoagulation may be necessary. Patients with isolated LA positivity suffered similar risks with secondary APS and patients with multiple cardiovascular risk factors. Attention should be paid to male patients, and the screening of cardiovascular risk factors should never be ignored.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13075-022-02814-w.

Laboratory Diagnosis of Antiphospholipid Syndrome: Insights and Hindrances

Diagnosis of antiphospholipid syndrome (APS) requires the presence of a clinical criterion (thrombosis and/or pregnancy morbidity), combined with persistently circulating antiphospholipid antibodies (aPL). Currently, laboratory criteria aPL consist of lupus anticoagulant (LAC), anticardiolipin antibodies (aCL) IgG/IgM, and anti-β2 glycoprotein I antibodies (aβ2GPI) IgG/IgM. Diagnosis and risk stratification of APS are complex and efforts to standardize and optimize laboratory tests have been ongoing since the initial description of the syndrome. LAC detection is based on functional coagulation assays, while aCL and aβ2GPI are measured with immunological solid-phase assays. LAC assays are especially prone to interference by anticoagulation therapy, but strategies to circumvent this interference are promising. Alternative techniques such as thrombin generation for LAC detection and to estimate LAC pathogenicity have been suggested, but are not applicable yet in routine setting. For aCL and aβ2GPI, a lot of different assays and detection techniques such as enzyme-linked immunosorbent and chemiluminescent assays are available. Furthermore, a lack of universal calibrators or standards results in high variability between the different solid-phase assays. Other non-criteria aPL such as anti-domain I β2 glycoprotein I and antiphosphatidylserine/prothrombin antibodies have been suggested for risk stratification purposes in APS, while their added value to diagnostic criteria seems limited. In this review, we will describe laboratory assays for diagnostic and risk evaluation in APS, integrating applicable guidelines and classification criteria. Current insights and hindrances are addressed with respect to both laboratory and clinical implications.

Risk of Thrombosis, Pregnancy Morbidity or Death in Antiphospholipid Syndrome

The antiphospholipid syndrome is an autoimmune disease characterized by thrombosis and pregnancy morbidity. The manifestations are caused by antibodies targeting cell membrane phospholipids and/or associated proteins. The triggers leading to these antibodies' production are unknown but recent work suggests cross-reactivity between the autoantigens and peptides produced by the intestinal microbiome. Work on how the autoantibodies could cause clinical manifestations implicates different mechanisms. Binding to surface proteins of different cell types can induce intracellular signaling leading to cell activation and tissue factor expression. Complement activation and neutrophil extracellular-traps are also involved, and recent evidence implicates endothelial protein C receptor-lysobisphosphatidic acid complex. Pregnancy is a high-risk situation for antiphospholipid syndrome patients due to the increased risk of thrombosis and obstetric complications. Epidemiological and clinical research on APS is hampered by heterogeneity in populations, testing and treatment strategies. About one in 10 to one in fifty APS pregnancies is complicated by thrombosis, despite treatment. Pregnant patients with prior thrombosis are prescribed therapeutic dose heparins and low dose aspirin. Without prior thrombosis a prophylactic dose is used. The most frequent obstetrical manifestation is recurrent early pregnancy loss. The association of APS antibodies with late pregnancy loss is stronger, however. Prevention of recurrence is achieved with aspirin and prophylactic dose heparin, although the evidence is of low certainty. The third obstetrical classifying manifestation comprises preterm delivery due to placenta-mediated complications and is treated in subsequent pregnancies with aspirin with or without prophylactic dose heparin, again based on low quality evidence. New therapies are under investigation.

Pediatric antiphospholipid syndrome: clinical features and therapeutic interventions in a single center retrospective case series

BACKGROUND/PURPOSE

Pediatric antiphospholipid syndrome (APS) is a thromboinflammatory disease characterized by the presence of circulating antiphospholipid antibodies and either thrombotic events or pregnancy morbidity. The objective of this study was to review a large institution's experience to better understand the characteristics of children with APS.

METHODS

We conducted a retrospective review of pediatric APS at a tertiary referral center. The electronic medical record system was queried from 2000 through 2019, and 21 cases were included based on meeting the revised Sapporo Classification criteria by age 18 or younger. Comparisons between primary and secondary APS patients were made with two-tailed t-tests.

RESULTS

Twenty-one patients were included with a median age at diagnosis of 16 years and median follow-up of 5.8 years. Secondary APS was slightly more common than primary APS (11 vs. 10 cases) and was primarily diagnosed in the context of systemic lupus erythematosus. Two thirds of patients (67%) also had "non-criteria" manifestations of APS including thrombocytopenia, autoimmune hemolytic anemia, and livedo reticularis/racemosa. Almost half of patients (43%) had recurrent thrombosis, typically when patients were subtherapeutic or non-adherent with anticoagulation. Damage Index in Patients with Thrombotic APS (DIAPS) scores indicated a chronic burden of disease in both primary and secondary APS patients.

CONCLUSION

This case series of pediatric APS provides important context regarding disease phenotypes displayed by children with APS. High prevalence of non-criteria clinical manifestations highlights the need to consider these characteristics when developing pediatric-specific classification criteria and when considering this relatively rare diagnosis in pediatric practice.

Kidney disease in antiphospholipid antibody syndrome: Risk factors, pathophysiology and management

Antiphospholipid antibody syndrome (APLS) is a rare autoimmune disease characterized by recurrent arterial and venous thromboembolic events, pregnancy related complications as well as the persistent detection of antiphospholipid antibodies at a 12 week interval. Renal complications tend to occur in 3% of APLS patients, with renal artery stenosis being the most common kidney related complication. Renal pathology may be subdivided into macro as well as microvascular thrombotic complications with stenosis, thrombosis and infarction representing the principle macrovascular events and APLS nephropathy representing the predominant microvascular complication. APLS related kidney disease may present with an array of heterogenous manifestations ranging from hematuria and non-nephrotic range proteinuria to hypertension or as part of a severe, life threatening and fulminant multiorgan failure disorder known as catastrophic antiphospholipid antibody syndrome (CAPS). Management of APLS related renal complications depends on the site of vascular injury, the thromboembolic risk profile based on the subtype, isotype and titer of the autoantibodies as well as the severity of the injury. Primary prophylaxis in these patients primarily revolves around the use of low dose aspirin, with prophylactic anticoagulation during events that increase thromboembolic like surgery and hospitalization. Anticoagulation is the cornerstone of treatment of APLS related kidney disease with INR targets varying depending on the associated venous or arterial thrombosis. Immunosuppression with the likes of rituximab, mTOR inhibitors, eculizumab and belimumab have been used with some success, but lack randomized control trial validation for their use. Pulsed corticosteroids with Plasmapheresis and intravenous immunoglobulins is the recommended treatment for CAPS.

Primary antiphospholipid syndrome in pediatrics: beyond thrombosis. Report of 32 cases and review of the evidence

OBJECTIVE

Describe the frequency of thrombotic and non-thrombotic clinical manifestations, laboratory, treatment and prognosis in patients with pediatric primary antiphospholipid syndrome.

MATERIAL AND METHODS

A retrospective study was carried out in patients with a diagnosis of primary antiphospholipid antibody syndrome, under 16 years of age, under follow-up by the pediatric rheumatology service of the General Hospital, National Medical Center, La Raza, from January 2013 to December 2020. The antiphospholipid syndrome was defined when it met the laboratory criteria of the Sidney criteria and the presence of thrombosis or non-criteria manifestations of the disease (hematological, neurological, cutaneous, renal, cardiac or pulmonary). Demographic, clinical, laboratory, treatment, and prognosis data were collected.

RESULTS

We report 32 patients, 21 female (65%) and 11 male (35%), mean age 11.75 years, evolution time 16 weeks. Thrombosis 9 patients (28%), 1 arterial and 8 venous. Non-thrombotic manifestations; Hematologic: thrombocytopenia 22 patients (69%), autoimmune hemolytic anemia 13 (40%), Fisher-Evans syndrome 6 (19%), lupus anticoagulant with hypoprothrombinemia syndrome 2 (6%). Dermatological: livedo reticularis 20 (62%), skin ulcers 2 (6%), Raynaud's phenomenon 8 (25%). Neurological: epilepsy 1 (3%), migraine 3 (9%), chorea 1 (3%) and cognitive impairment 3 (9%). Renal in 4 (13%). Laboratory: prolonged aPTT 30 (93%), lupus anticoagulant 32 (100%), positive IgG anticardiolipin 20 (62%), positive IgM anticardiolipin 19 (60%). AntiB2GPI was performed in only 3 patients, being positive in all.

TREATMENT

anticoagulation in patients with thrombosis, antiplatelet in 23 (72%), steroid 30 (94%), immunosuppressant 30 (94%) and rituximab 4 (12.5%). No deaths were reported.

CONCLUSIONS

The clinical characteristics of patients with pediatric primary antiphospholipid syndrome differ from those presented in adults, since non-thrombotic manifestations are more frequent in children, for which classification criteria that include these manifestations are necessary for a better characterization of the disease in pediatric population.

Characteristics of Patients With Antiphospholipid Antibody Positivity in the APS ACTION International Clinical Database and Repository

OBJECTIVE

To describe the baseline characteristics of patients with positivity for antiphospholipid antibodies (aPLs) who were enrolled in an international registry, the Antiphospholipid Syndrome (APS) Alliance for Clinical Trials and International Networking (APS ACTION) clinical database and repository, overall and by clinical and laboratory subtypes.

METHODS

The APS ACTION registry includes adults who persistently had positivity for aPLs. We evaluated baseline sociodemographic and aPL-related (APS classification criteria and "non-criteria") characteristics of patients overall and in subgroups (aPL-positive without APS, APS overall, thrombotic APS only, obstetric APS only, and both thrombotic APS/obstetric APS). We assessed baseline characteristics of patients tested for the presence of three aPLs (lupus anticoagulant [LAC] test, anticardiolipin antibody [aCL], and anti-β2 -glycoprotein I [anti-β2 GPI]) antibodies by aPL profiles (LAC only, single, double, and triple aPL positivity).

RESULTS

The 804 aPL-positive patients assessed in the present study had a mean age of 45 ± 13 years, were 74% female, and 68% White; additionally, 36% had other systemic autoimmune diseases. Of these 804 aPL-positive patients, 80% were classified as having APS (with 55% having thrombotic APS, 9% obstetric APS, and 15% thrombotic APS/obstetric APS). In the overall cohort, 71% had vascular thrombosis, 50% with a history of pregnancy had obstetric morbidity, and 56% had experienced at least one non-criteria manifestation. Among those with three aPLs tested (n = 660), 42% were triple aPL-positive. While single-, double-, and triple aPL-positive subgroups had similar frequencies of vascular, obstetric, and non-criteria events, these events were lowest in the single aPL subgroup, which consisted of aCLs or anti-β2 GPI only.

CONCLUSION

Our study demonstrates the heterogeneity of aPL-related clinical manifestations and laboratory profiles in a multicenter international cohort. Within single aPL positivity, LAC may be a major contributor to clinical events. Future prospective analyses, using standardized core laboratory aPL tests, will help clarify aPL risk profiles and improve risk stratification.

Pathogenesis, Diagnosis and Management of Obstetric Antiphospholipid Syndrome: A Comprehensive Review

Antiphospholipid syndrome is an autoimmune disorder characterized by vascular thrombosis and/or pregnancy morbidity associated with persistent antiphospholipid antibody positivity. Cases fulfilling the Sydney criteria for obstetric morbidity with no previous thrombosis are known as obstetric antiphospholipid syndrome (OAPS). OAPS is the most identified cause of recurrent pregnancy loss and late-pregnancy morbidity related to placental injury. Cases with incomplete clinical or laboratory data are classified as obstetric morbidity APS (OMAPS) and non-criteria OAPS (NC-OAPS), respectively. Inflammatory and thrombotic mechanisms are involved in the pathophysiology of OAPS. Trophoblasts, endothelium, platelets and innate immune cells are key cellular players. Complement activation plays a crucial pathogenic role. Secondary placental thrombosis appears by clot formation in response to tissue factor activation. New risk assessment tools could improve the prediction of obstetric complication recurrences or thromboses. The standard-of-care treatment consists of low-dose aspirin and prophylactic low molecular weight heparin. In refractory cases, the addition of hydroxychloroquine, low-dose prednisone or IVIG improve pregnancy outcomes. Statins and eculizumab are currently being tested for treating selected OAPS women. Finally, we revisited recent insights and concerns about the pathophysiology, diagnosis and management of OAPS.

Non-criteria manifestations in primary antiphospholipid syndrome: a French multicenter retrospective cohort study

Background

From this retrospective study, we aimed to (1) describe the prevalence and characteristics of non-criteria features in primary antiphospholipid syndrome (p-APS) and (2) determine their prognostic value.

Methods

This retrospective French multicenter cohort study included all patients diagnosed with p-APS (Sydney criteria) between January 2012 and January 2019. We used Kaplan-Meier and adjusted Cox proportional hazards models to compare the incidence of relapse in p-APS with and without non-criteria manifestations.

Results

One hundred and seventy-nine patients with p-APS were included during the study time, with a median age of 52.50 years [39.0; 65.25] and mainly women (n = 112; 62.6%). Among them, forty-three patients (24.0%) presented at least one non-criteria manifestation during the follow-up: autoimmune cytopenias (n = 17; 39.5%), Libman Sachs endocarditis (n = 5; 11.6%), APS nephropathy (n = 4; 9.3%), livedo reticularis (n = 8; 18.6%), and neurological manifestations (n = 12; 27.9%). In comparison to p-APS without any non-criteria manifestations (n = 136), p-APS with non-criteria features had more arterial thrombosis (n = 24; 55.8% vs n = 48; 35.3%; p = 0.027) and more frequent pre-eclampsia (n = 6; 14.3% vs n = 4; 3.1%; p = 0.02). The prevalence of triple positivity was significantly increased in patients with non-criteria features (n = 20; 47.6% vs n = 25; 19.8%; p = 0.001). Patients with p-APS and non-criteria manifestations (n = 43) received significantly more additional therapies combined with vitamin K antagonists and/or antiaggregants. Catastrophic APS (CAPS) tended to be more frequent in p-APS with non-criteria features (n = 2; 5.1% vs none; p = 0.074).

The p-APS with non-criteria manifestations had significantly increased rates of relapse (n = 20; 58.8% vs 33; 33.7%; p = 0.018) in bivariate analysis, but in survival analyses, the hazard ratio (HR) of relapse was not significantly different between the two groups (HR at 1.34 [0.67; 2.68]; p = 0.40).

Conclusions

The presence of non-criteria features is important to consider, as they are associated with particular clinical and laboratory profiles, increased risk of relapse, and need for additional therapies. Prospective studies are necessary to better stratify the prognosis and the management of p-APS.

Thrombocytopenia in a cohort of primary and secondary antiphospholipid syndrome patients: Relation to clinical, laboratory manifestations and damage index

Objectives

This study aims to evaluate the prevalence of thrombocytopenia in a cohort of patients with primary and secondary antiphospholipid syndrome (APS) and to examine the relation of thrombocytopenia to the clinical, laboratory findings, and damage index for antiphospholipid syndrome (DIAPS).

Patients and methods

Between August 2018 and February 2019, a total of 168 patients (16 males, 152 females; mean age: 32.5±8.4 years; range, 18 to 59 years) who were followed in our clinic for APS were retrospectively analyzed. Medical records of the patients were screened and clinical data, laboratory investigations, and treatments applied were recorded. The DIAPS was calculated for all patients. The patients were divided into two groups according to the presence or absence of thrombocytopenia and both groups were compared regarding clinical, laboratory findings and DIAPS. Further subgroup analysis was done for patients with primary APS.

Results

The most common clinical manifestations in our patients were obstetric manifestations (77.4% in pregnant women), musculoskeletal manifestations (69%) and peripheral vascular thrombosis (54.8%). The prevalence of thrombocytopenia in our study was 42.3%, and it was significantly associated with musculoskeletal manifestations (p=0.043), vascular thrombosis (p=0.043), neurological manifestations (p=0.030), cutaneous manifestations (p=0.006), and use of immunosuppressives (p=0.047). The DIAPS was significantly higher in the thrombocytopenia group (p=0.034). Further subgroup analysis of patients with primary APS revealed that neurological manifestations (p=0.010) were significantly higher in the thrombocytopenia group, while the DIAPS was higher in the thrombocytopenia group, but it did not reach statistical significance (p=0.082).

Conclusion

Thrombocytopenia may be associated with a higher incidence of vascular thrombosis, neurological manifestations, musculoskeletal manifestations, use of immunosuppressive treatment, and DIAPS. In primary APS patients, thrombocytopenia may be a risk for neurological manifestations.

Characteristics and risk factors of retinal vasculopathy in antiphospholipid syndrome

BACKGROUND

Retinal vasculopathy including retinal artery occlusion (RAO) or retinal vein occlusion (RVO) was recently found to occur more frequently in antiphospholipid syndrome (APS) patients than non-APS patients. This study aims to investigate the clinical manifestation and risk factors of retinal vasculopathy among APS patients.

METHODS

In this single-center prospective cohort study, we evaluated APS patients with or without retinal vasculopathy during 2018-2020 at Peking Union Medical College Hospital. Clinical variables were compared, and a logistical regression model was built to explore risk factors. Hierarchical cluster analysis using Euclidean distances was applied to identify clusters of variables.

RESULTS

A total of 310 APS patients (67.4% female, mean age 38.1 years) were included, of whom 18 (5.8%) were diagnosed with retinal vasculopathy (9 with RVO and 9 with RAO). No significant differences were found among most demographic characteristics, clinical manifestations, or antibody profiles. APS-related heart valve disease (odds ratio OR 13.66, 95% confidence interval CI 4.55-40.98), APS nephropathy (OR 12.77, 95% CI 4.04-40.35), and thrombocytopenia (OR 2.63, 95% CI 1.01-6.89) were predictive of retinal vasculopathy. APS-related heart valve disease and nephropathy were also found to be statistically significant predictors in multivariate logistical regression analysis. Non-criteria manifestations were aggregated with retinal vasculopathy from a cluster analysis of variables.

CONCLUSION

Patients with APS-related heart valve disease and nephropathy suffered a higher risk of retinal vasculopathy. The underlying mechanisms of aPL-associated retinal vasculopathy may involve thrombotic microangiopathy, leading to poor prognosis and therapeutic changes.

The presence of non-criteria manifestations negatively affects the prognosis of seronegative antiphospholipid syndrome patients: a multicenter study

Background

Seronegative antiphospholipid syndrome (SN-APS) is often defined as the presence of APS criteria manifestations, negative antiphospholipid antibodies (aPL), and coexistence of APS non-criteria manifestations. Nevertheless, the impact of these non-criteria features is still unclear. On a different note, the relevance of one single aPL positive determination in patients with APS manifestations is another domain with limited evidence. We aim to compare the course of SN-APS and single-positive aPL (SP-aPL) patients with that of individuals with APS manifestations without non-criteria features/aPL positivity (controls).

Methods

Retrospective analysis of patients with thrombosis/obstetric morbidity assessed in two European hospitals between 2005 and 2020. Patients were divided into SN-APS, SP-aPL, and control groups. Clinical characteristics, comorbidities, and therapies were compared.

Results

A total of 82 patients were included in the SN-APS group, 88 in the SP-aPL group, and 185 in the control group. In Cox regression model, SN-APS displayed more thrombosis recurrence than controls (HR 3.8, 95% CI 2.2–6.5, p < 0.001) even when adjusting for the presence of hereditary thrombophilia, systemic lupus erythematosus, or contraceptive hormonal treatment. In SP-aPL, the difference in thrombosis recurrence did not reach statistical significance (p = 0.078). Indefinite anticoagulation (p < 0.001 and p = 0.008, respectively) and vitamin K antagonist (VKA) use (p < 0.001 in both cases) were more common in SN-APS/SP-aPL.

Conclusion

SN-APS displayed more thrombosis recurrence, indefinite anticoagulation, and VKA use than controls without non-criteria manifestations. The presence of such features in patients with thrombosis and negative aPL may negatively impact their clinical course.

Severe digital ischemia coexists with thrombocytopenia in malignancy-associated antiphospholipid syndrome: A case report and review of literature

BACKGROUND

Paraneoplastic syndromes are characterized by atypical clinical manifestations. Several reports of hepatocellular carcinoma (HCC) paraneoplastic phenomena have been reported. They usually manifest as one type in an individual, but it is not common for the two clinical manifestations to occur simultaneously.

CASE SUMMARY

A 52-year-old female patient was admitted to hospital with pale skin and numbness of the second to fifth fingers in the left hand, which rapidly developed into severe digital ischemia. Computed tomography angiography revealed uneven thickness of the left ulnar artery with severe local luminal stenosis. Blood analysis during hospitalization showed persistent mild to medium thrombocytopenia and insensitive to hormonal therapy. Antiphospholipid antibody testing showed high titer of IgG anticardiolipin antibodies (aCLs), IgA aCLs, IgG anti-β2-glycoprotein-I (anti-β2 GPI), and IgA anti-β2 GPI. The exact diagnosis was HCC when the high a-fetoprotein levels, computed tomography findings, and the history of chronic hepatitis B came together. This was a rare case of coexisting manifestations as presenting symptoms of malignancy-associated antiphospholipid syndrome. The patient underwent several operations, antithrombotic treatments and hormonal therapy. However, the patient refused chemotherapy and died 8 wk after diagnosis.

CONCLUSION

This report highlights the importance of atypical clinical changes that could alert the physicians to vigilance for a concomitant underlying malignancy.

Immunomodulation in antiphospholipid-antibody-associated endocarditis: a case report and review of the literature

Background

Non-infectious endocarditis is a rare complication in patients with systemic lupus erythematosus or antiphospholipid syndrome (APS). The mitral valve is mainly affected, usually showing vegetations on the ventricular and atrial side of the valve.

Case summary

A 27-year-old female patient with a known APS was referred to our hospital with night sweats, weight loss, reduction in performance, and dizziness. A floating structure associated to the mitral valve was identified in a transoesophageal echocardiogram with typical changes, in accordance with a non-infectious endocarditis (Libman–Sacks). Only a trace of mitral regurgitation was present and a mass on the posterior mitral valve leaflet. Laboratory findings showed antibody and inflammatory marker measurements either negative or within normal range. The patient received therapeutic oral anticoagulation using a vitamin K antagonist and a combined immunosuppression consisting of hydroxychloroquine and prednisolone. The symptoms of the patient resolved within 3 months after starting the initial treatment. The follow-up echocardiogram showed an almost normal mitral valve function with only a slight regional thickening of the posterior mitral leaflet and no stenosis. Following a 7-year period of observation being on a medical regimen of hydroxychloroquine and a vitamin K antagonist, no evidence of clinical and/or echocardiographic recurrence was detected.

Discussion

This case report represents a successful medical management of non-infectious endocarditis using immunosuppressive and anticoagulation therapies without significant residual lesions. Although optimal management of non-bacterial endocarditis remains in the area of uncertainty, this combination therapy deems promising.

Oxidative Stress in the Pathogenesis of Antiphospholipid Syndrome: Implications for the Atherothrombotic Process

Atherothrombosis is a frequent complication of the clinical history of patients with antiphospholipid syndrome (APS). Both atherothrombosis and APS are characterized by increased oxidative stress. Oxidative modifications are implicated in the formation of antiphospholipid antibodies, which in turn may favour the oxidative imbalance by increasing the production of reactive oxidant species (ROS) or by a direct interaction with pro-oxidant/antioxidant enzymes. As a result of these processes, APS patients suffer from an oxidative imbalance that may contribute to the progression of the atherosclerotic process and to the onset of ischemic thrombotic complications. The aim of this review is to describe mechanisms implicated in the formation of ROS in APS patients and their involvement in the atherothrombotic process. We also provide an overview of potential therapeutic approaches to blunt oxidative stress and to prevent atherothrombotic complications in these patients.

Myocardial involvement in anti-phospholipid syndrome: Beyond acute myocardial infarction

Anti-phospholipid antibodies (aPL) are the serological biomarkers of anti-phospholipid syndrome (APS), an autoimmune disorder characterized by vascular events and/or pregnancy morbidity. APS is a unique condition as thrombosis might occur in arterial, venous or capillary circulations. The heart provides a frequent target for circulating aPL, leading to a wide variety of clinical manifestations. The most common cardiac presentation in APS, valvular involvement, acknowledges a dual etiology comprising both microthrombotic and inflammatory mechanisms. We describe the cases of 4 patients with primary APS who presented a clinically manifest myocardiopathy without epicardial macrovascular distribution. We propose that microthrombotic/inflammatory myocardiopathy might be an overlooked complication of high-risk APS. As extensively hereby reviewed, the literature provides support to this hypothesis in terms of anecdotal case-reports, in some cases with myocardial bioptic specimens. In aPL-positive subjects, microthrombotic/inflammatory myocardial involvement might also clinically manifest as dilated cardiomyopathy, a clinical entity characterized by ventricular dilation and reduced cardiac output. Furthermore, microthrombotic/inflammatory myocardial involvement might be subclinical, presenting as diastolic dysfunction. Currently, there is no single clinical or imaging finding to firmly confirm the diagnosis; an integrated approach including clinical history, clinical assessment, laboratory tests and cardiac magnetic resonance should be pursued in patients with suggestive clinical presentation.