Differences in Antiphospholipid Antibody Profile between Patients with Obstetric and Thrombotic Antiphospholipid Syndrome

Identification of Three Distinct Subgroups in Antiphospholipid Syndrome: Implication for Sex Differences and Prognostic Outcomes from a Multicenter Study

Antiphospholipid syndrome (APS) is a heterogeneous autoimmune disease with persistent antiphospholipid antibodies. This study aimed to identify unrecognized APS subgroups from multicenter cohorts (n = 760, training: n = 415; validation: n = 345). Patients are stratified through unsupervised K-means clustering analysis. Prognostic outcomes are evaluated using Kaplan-Meier survival analyses. Proteomic analysis is conducted on primary APS patients (n = 36) and healthy controls (n = 12). Key molecule insulin-like growth factor 1 is validated using ELISA. Three clusters are identified. Cluster 1 (n = 320, 42.1%) is completely consisted of females (100%), with predominant occurrence of pregnancy morbidity (88.8%) but low incidences of thrombocytopenia (18.4%) and thrombosis (15.0%), and a favorable prognosis. Cluster 2 (n = 309, 40.7%) is predominantly female (99.4%) and characterized by high thrombosis (85.8%) and thrombocytopenia (46.6%), low pregnancy morbidity (13.6%), and poor prognosis. Cluster 3 (n = 131, 17.2%) is predominantly male (99.2%), exhibiting highest thrombosis (96.2%) and moderate thrombocytopenia (32.8%), with worst prognosis. Immunological and proteomic analyses clearly differentiated three clusters. This study reveals a distinct difference between obstetric and thrombotic APS, and a sex-based distinction within thrombotic APS. Three APS subgroups display unique clinical and molecular characteristics, and marked difference in prognostic outcomes.

Antiphospholipid syndrome in pregnancy: a comprehensive literature review

BACKGROUND

Antiphospholipid syndrome (APS) is an autoimmune disorder associated with thrombotic events and adverse obstetric outcomes, particularly in its obstetric form (OAPS). Affecting approximately 0.5% of the population, APS is a leading contributor to recurrent pregnancy loss (RPL), preeclampsia (PE), and fetal growth restriction ((FGR). Despite advancements in understanding its pathophysiology and management, optimal treatment strategies for APS in pregnancy remain challenging and require systematic evaluation. This review synthesizes current evidence on APS mechanisms, diagnostic criteria, and therapeutic interventions, with a focus on maternal and fetal outcomes in OAPS.

METHODS

A comprehensive search of PubMed, was conducted to identify studies exploring APS pathogenesis, diagnostic standards, and treatment efficacy in obstetric settings. Inclusion criteria prioritized randomized controlled trials, cohort studies, and systematic reviews with a clear focus on APS and pregnancy.

RESULTS

The review confirmed that APS current accepted pathogenesis is governed by a "two-hit" model, where antiphospholipid antibodies (aPLs) initiate endothelial damage, culminating in thrombosis and placental insufficiency. Epidemiological analysis underscores the prevalence and severity of APS in obstetric contexts, with lupus anticoagulant (LA) emerging as a significant predictor of adverse outcomes. Evidence supports the use of low-dose aspirin (LDA) and heparin to reduce miscarriage rates, while adjunctive treatments, such as hydroxychloroquine (HCQ), have shown promise in improving live birth rates and reducing preterm delivery in high-risk cases. Emerging therapies, including tumoral necrosis factor (TNF-alpha) inhibitors and nitric oxide modulators, may offer additional benefits in refractory cases.

CONCLUSION

APS remains a critical determinant of adverse pregnancy outcomes, necessitating precise diagnostic criteria and tailored management approaches. This systematic review emphasizes the importance of individualized therapeutic regimens to optimize maternal and fetal health in OAPS and highlights areas for future research, particularly regarding novel pharmacological approaches. Further studies are essential to refine treatment protocols and improve clinical guidelines for managing APS in pregnancy.

Antiphospholipid syndrome in pregnancy: A comprehensive review

Antiphospholipid syndrome (APS) is a systemic autoimmune disorder characterized by the presence of antiphospholipid antibodies and is associated with thrombotic events and pregnancy complications. The classification and management of APS has evolved over time. The classification criteria for APS include laboratory, macrovascular, microvascular, obstetric, cardiac, and hematologic domains. Management focuses on prevention of thrombotic events and/or anticoagulation as the primary treatment for thrombosis. Postpartum and long-term thromboprophylaxis after delivery are recommended to reduce the risk of thrombotic events. Despite these recommendations, optimal anticoagulation agents and intensity of treatment are still topics of debate. Further research is needed to understand the pathophysiology of APS and improve its management during pregnancy. In this review, we discuss the classification and pathophysiology of APS. Current treatment options and clinical trials are also discussed.

Effects of Bushen Huoxue on integrin β3 and integrin β5 in the placental tissue of mice with repeated implantation failure caused by phospholipid antibodies

BACKGROUND

This study aimed to investigate the effects of the Kidney-Tonifying and Blood-Activating Formula on combating the downregulation of integrin β3 and integrin β5 in mouse placental tissue induced by phospholipid antibodies.

OBJECTIVE

This study aimed to investigate the effects of kidney-tonifying and blood-activating formulations on combating the downregulation of integrin β3 and integrin β5 in mouse placental tissue induced by phospholipid antibodies.

METHODS

Mice in the phospholipid antibody group and phospholipid antibody + kidney-tonifying and blood-activating formula group underwent repeated implantation experiments, and the expression of integrin β3 and integrin β5 in placental tissue was observed. The effects of the kidney-tonifying and blood-activating formula on mouse placental tissue were evaluated through biochemical index tests, histopathological observations, and immunohistochemical staining.

RESULTS

After intervention with the kidney-tonifying and blood-activating formula, the expression of integrin β3 and integrin β5 in placental tissue was notably upregulated, and placental structure was restored. Kidney-Tonifying and Blood-Activating Formula significantly improved abnormal biochemical indices and exerted a remarkable protective effect on placental tissue pathology.

CONCLUSION

The kidney-tonifying and blood-activating formula effectively counteracted the downregulation of integrin β3 and integrin β5 in mouse placental tissue induced by phospholipid antibodies and alleviated placental tissue pathology through structural improvement and protection. Therefore, kidney-tonifying and blood-activating formulas may serve as potential therapeutic agents for recurrent implantation failure, offering new insights and approaches for clinical treatment.

High Prevalence of Anti-Prothrombin IgM and IgG Autoantibodies in Women With Unexplained Recurrent Pregnancy Loss

To investigate the association between anti-prothrombin IgM and IgG antibodies and recurrent pregnancy loss (RPL) in a cohort of Lebanese women, and their impact on pregnancy outcomes. This was a retrospective case-control study involving 207 women with RPL and 179 age-matched multiparous controls. Quantitative sandwich ELISA assayed anti-prothrombin IgM and IgG antibodies. Univariate and multivariate logistic regression were employed to assess the risk imparted by anti-prothrombin antibodies, while ROC analysis was used to determine their sensitivity and specificity. Our study revealed that women with RPL had significantly higher serum levels of anti-prothrombin IgM and IgG than controls. Univariate regression analysis demonstrated that elevated anti-prothrombin IgM (OR = 1.13; 95% CI = 1.07, 1.19; P < 0.001) and IgG (OR = 1.05; 95% CI = 1.03, 1.08; P < 0.001) were associated with increased RPL risk. Multivariate analysis confirmed these findings, indicating that anti-prothrombin IgM (aOR = 1.13; 95% CI = 1.05, 1.20; P < 0.001) and IgG (aOR = 1.08; 95% CI = 1.05, 1.11; P < 0.001) are independent risk factors. ROC analysis yielded an AUC of 0.720 for IgM and 0.649 for IgG, underscoring their predictive value and offering hope for improved risk assessment and management of RPL. Elevated levels of anti-prothrombin IgM and IgG are significantly associated with RPL, suggesting an autoimmune component to pregnancy loss. These findings highlight the importance of screening for these antibodies in women with unexplained RPL to guide management and therapeutic strategies.

Obstetric antiphospholipid syndrome carries an increased lifetime risk for obstetric and thrombotic complications-a population-based study

Background

Antiphospholipid syndrome (APS) can present with either a thromboembolic event (thrombotic APS, TAPS) or an obstetric complication (obstetric APS, OAPS). Data on long-term complications in the different APS phenotypes are limited.

Objectives

We aimed to compare obstetric history, antiphospholipid antibody profiles, obstetric and thromboembolic complications, and pregnancy outcomes between TAPS and OAPS.

Methods

This retrospective cohort study included women who delivered singleton pregnancies between 1998 and 2020. One hundred sixteen thousand four hundred nine women were included, resulting in 320,455 deliveries. Among the included patients, 71 were diagnosed with APS, 49 were classified as OAPS, and 22 as TAPS. The demographics, obstetric, neonatal, and thrombotic outcomes were compared among TAPS, OAPS, and the general obstetric population.

Results

OAPS patients had an increased risk of thrombotic events compared with the general obstetric population (odds ratio [OR] 18.0; 95% CI, 8.7-37.2). In pregnancies following the diagnosis of APS, despite standard antithrombotic treatment, OAPS patients exhibited an elevated risk of placenta-related and neonatal complications compared with the general obstetric population (late fetal loss [adjusted OR {aOR}, 15.3; 95% CI, 0.5-27.5], stillbirth [aOR, 5.9; 95% CI, 2.2-15.4], placental abruption [aOR, 4.8; 95% CI, 1.5-15.3], preeclampsia [aOR, 4.4; 95% CI, 2.5-7.7], fetal growth restriction [aOR, 4.3; 95% CI, 8.5-27.5], small for gestational age neonate [aOR, 4.0; 95% CI, 2.4-6.6], and low Apgar scores [Apgar'1: aOR, 2.6; 95% CI, 1.3-10.4; Apgar'5: aOR, 3.7; 95% CI, 1.3-10.4]). TAPS patients exhibited increased risk of preeclampsia (aOR, 3.1; 95% CI, 1.2-8).

Conclusion

OAPS patients exhibit a heightened risk of thrombotic events compared with the general obstetric population. Despite treatment, OAPS and TAPS still presented obstetric complications. These findings, after confirmation in prospective studies, need to be taken into consideration when planning the treatment approach for these patients.

Thrombosis and Hyperinflammation in COVID-19 Acute Phase Are Related to Anti-Phosphatidylserine and Anti-Phosphatidylinositol Antibody Positivity

Antiphospholipid antibodies (APLA) are strongly associated with thrombosis seen in patients with antiphospholipid syndrome. In COVID-19, thrombosis has been observed as one of the main comorbidities. In patients hospitalised for COVID-19, we want to check whether APLA positivity is associated with COVID-19-related thrombosis, inflammation, severity of disease, or long COVID-19. We enrolled 92 hospitalised patients with COVID-19 between March and April 2020 who were tested for 18 different APLAs (IgG and IgM) with a single line-immunoassay test. A total of 30 healthy blood donors were used to set the cut-off for each APLA positivity. Of the 92 COVID-19 inpatients, 30 (32.61%; 95% CI [23.41-43.29]) tested positive for APLA, of whom 10 (33.3%; 95% CI [17.94-52.86]) had more than one APLA positivity. Anti-phosphatidylserine IgM positivity was described in 5.4% of inpatients (n = 5) and was associated with the occurrence of COVID-19-related thrombosis (p = 0.046). Anti-cardiolipin IgM positivity was the most prevalent among the inpatients (n = 12, 13.0%) and was associated with a recorded thrombosis in their clinical history (p = 0.044); however, its positivity was not associated with the occurrence of thrombosis during their hospitalisation for COVID-19. Anti-phosphatidylinositol IgM positivity, with a prevalence of 5.4% (n = 5), was associated with higher levels of interleukin (IL)-6 (p = 0.007) and ferritin (p = 0.034). Neither of these APLA positivities was a risk factor for COVID-19 severity or a predictive marker for long COVID-19. In conclusion, almost a third of COVID-19 inpatients tested positive for at least one APLA. Anti-phosphatidylserine positivity in IgM class was associated with thrombosis, and anti-phosphatidylinositol positivity in IgM class was associated with inflammation, as noticed by elevated levels of IL-6. Thus, testing for non-criteria APLA to assess the risk of clinical complications in hospitalised COVID-19 patients might be beneficial. However, they were not related to disease severity or long COVID-19.

Added value of antiphosphatidylserine/prothrombin antibodies in the workup of obstetric antiphospholipid syndrome: communication from the ISTH SSC Subcommittee on Lupus Anticoagulant/Antiphospholipid Antibodies

BACKGROUND

The added value of antiphosphatidylserine/prothrombin antibodies (aPS/PT) in the diagnostic workup of antiphospholipid syndrome (APS) is unclear. Currently, diagnosis of thrombotic APS (TAPS) and obstetric APS (OAPS) requires persistent presence of lupus anticoagulant (LAC), anticardiolipin (aCL) immunoglobulin (Ig) G/IgM, or anti-β2-glycoprotein I (aβ2GPI) IgG/IgM antibodies.

OBJECTIVES

To evaluate the role of aPS/PT IgG and IgM in OAPS.

METHODS

aPS/PT IgG/IgM, aCL IgG/IgM, aβ2GPI IgG/IgM, and LAC were determined in 653 patients (OAPS, TAPS, and controls). In-house aPS/PT cut-off values were calculated, titers and prevalence were compared between OAPS, TAPS, and controls and type of pregnancy morbidity. Sensitivity, specificity, likelihood ratios, and odds ratios (OR) with 95% CI were calculated.

RESULTS

In OAPS, aPS/PT IgG and IgM showed an OR of 4.32 (95% CI, 2.54-7.36) and 3.37 (95% CI, 1.93-5.89), respectively, but the association was not independent of LAC. Prevalence and titers of aPS/PT IgG and IgM were lower in OAPS than in patients with TAPS. aPS/PT were more prevalent and showed higher titers in patients with late pregnancy loss than in patients with early pregnancy loss with a positivity of 86.4% and 39.3%, respectively. Higher aPS/PT titers did not increase the likelihood of having OAPS.

CONCLUSION

The added value of aPS/PT testing in the current diagnostic workup of OAPS seems limited compared with LAC, aCL, and aβ2GPI. aPS/PT might be useful in specific subsets of patients with OAPS. However, future multicentric studies are needed to elucidate the risk of less frequent and most severe obstetrical manifestations.

Antiphospholipid Syndrome in Pregnancy: New and Old Pathogenetic Mechanisms

The antiphospholipid syndrome (APS) is a systemic autoimmune disorder characterized, according to the Sydney criteria, by the persistent presence of autoantibodies directed against phospholipid-binding proteins associated with thrombosis and/or obstetrical complications. The most frequent complications in obstetric antiphospholipid syndrome are recurrent pregnancy losses and premature birth due to placental insufficiency or severe preeclampsia. In recent years, vascular APS (VAPS) and obstetric APS (OAPS) have been described as two different clinical entities. In VAPS, antiphospholipid antibodies (aPL) interfere with the mechanisms of coagulation cascade and the 'two hit hypothesis' has been suggested to explain why aPL positivity does not always lead to thrombosis. OAPS seems to involve additional mechanisms, such as the direct action of anti-β2 glycoprotein-I on trophoblast cells that can lead to a direct placental functional damage. Furthermore, new actors seem to play a role in the pathogenesis of OAPS, including extracellular vesicles, micro-RNAs and the release of neutrophil extracellular traps. The aim of this review is to investigate the state-of-the-art antiphospholipid syndrome pathogenesis in pregnancy, in order to provide a comprehensive overview of both old and new pathogenetic mechanisms involved in this complex disease.

Studying Pregnancy Outcome Risk in Patients with Systemic Lupus Erythematosus Based on Cluster Analysis

Background. Pregnancy in systemic lupus erythematosus (SLE) patients is a challenge due to the potential maternal and fetal complications. Therefore, a multidisciplinary assessment of disease risk before and during pregnancy is essential to improve pregnancy outcomes. Objectives. Our purpose was to (i) define clusters of patients with similar history and laboratory features and determine the associative maternal and perinatal outcomes and (ii) evaluate the risk spectrum of maternal and perinatal outcomes of pregnancy in SLE patients, represented by our established risk-assessment chart. Methods. Medical records of 119 patients in China were analyzed retrospectively. Significant variables with $p<0.05$ were selected. The self-organizing map was used for clustering the data based on historical background and laboratory features. Results. Clustering was conducted using 21 maternal and perinatal features. Five clusters were recognized, and their prominent maternal manifestations were as follows: cluster 1 (including 27.73% of all patients): preeclampsia and lupus nephritis; cluster 2 (22.69%): oligohydramnios, uterus scar, and femoral head necrosis; cluster 3 (13.45%): upper respiratory tract infection; cluster 4 (15.97%): premature membrane rupture; and cluster 5 (20.17%): no problem. Conclusion. Pregnancy outcomes in SLE women fell into three categories, namely high risk, moderate risk, and low risk. Present manifestations, besides the medical records, are a potential assessment means for better management of pregnant SLE patients.