Obstetric antiphospholipid syndrome: current uncertainties should guide our way

Severe thrombocytopenia is associated with adverse pregnancy outcomes in patients with obstetric antiphospholipid syndrome

BACKGROUND

Thrombocytopenia is a common manifestation of antiphospholipid syndrome (APS). This study assesses the possible relationship between severe thrombocytopenia and adverse pregnancy outcomes (APOs) in obstetric APS (OAPS) patients.

METHODS

An observational, cohort study was conducted at Peking University People's Hospital, Beijing, China. The demographic, clinical, immunologic, and pregnancy outcomes of the OAPS patients were collected. Univariate and multivariate logistic regression analyses were applied to assess the association between APOs and severe thrombocytopenia (< 30 × 109/L). The threshold effect was explored using two piecewise linear regression models by the smoothing plot.

RESULTS

A total of 176 OAPS participants were included in the analysis, with 49 thrombocytopenia (< 100 × 109/L) and 9 severe thrombocytopenia (< 30 × 109/L). In the context of univariate logistic regression, severe thrombocytopenia demonstrated a significant association with increased APOs, encompassing preterm delivery before 34 weeks (OR, 8.74; 95%CI, 2.10-36.32, P = 0.0028), uteroplacental insufficiency (OR, 16.28; 95%CI, 1.99-133.53, P = 0.0093), preterm labor before 37 weeks (OR, 15.98; 95%CI, 3.16-80.80, P = 0.0008), and SGA (OR, 7.45; 95%CI, 1.87-29.73, P = 0.0045). A nonlinear relationship between the number of platelets and APOs was observed. The risk of APOs rose as platelet count decreased to a turning point (50 × 109/L) (P < 0.05). Beyond a platelet count of 50 × 109/L, no significant association was observed between platelet count and APO risk in OAPS patients.

CONCLUSION

The risk of adverse pregnancy outcomes in patients with OAPS is contingent upon the severity of thrombocytopenia. Maintaining platelet counts above 50 × 109/L is pivotal in mitigating this risk. The effective OAPS treatments may improve pregnancy outcomes.

Recurrent miscarriage and low-titer antiphospholipid antibodies

OBJECTIVE

To evaluate the clinical features and pregnancy outcomes in patients experiencing recurrent miscarriage (RM) with either low-titer or medium-high titer positivity of antiphospholipid antibodies (aPL).

METHODS

A retrospective review of medical records was conducted for patients with aPL positivity and recurrent miscarriage between 2018 and 2022. The clinical features, treatment strategies, outcomes were compared between the patients with low (n = 92) and medium (n = 32) titer of aPL.

RESULTS

A total of 118 patients, resulting in 124 obstetric episodes (pregnancies), with a mean age of 33. 15 ± 4.56 and 31.47 ± 4.41 years between the two groups. The low-titer group exhibited a higher frequency of anti-cardiolipin antibodies IgM (P < 0.001), whereas the medium-high titer group demonstrated a higher frequency of anti-β2-glycoprotein 1 antibodies IgG (P < 0.001) and IgM (P = 0.032). Moreover, the medium-high titer group displayed a significantly elevated erythrocyte sedimentation rate compared to the low-titer group (P < 0.05). In the low-titer group, 71 patients (77.2%) received appropriate treatment, resulting in 48 live births (67.6%) and 23 repeat abortions (32.4%). In the medium-high titer group, 29 patients (90.6%) received relevant treatment, leading to 23 live births (79.3%) and 6 repeat abortions (20.7%). No significant differences were observed in live births or maternal-fetal complications between the two groups (all P > 0.05).

CONCLUSION

Noteworthy distinctions in laboratory parameters were identified between the low-titer and medium-high titer groups. However, when appropriately treated, the fetal-maternal outcomes were comparable in both groups. Timely intervention by clinicians is imperative to enhance pregnancy outcomes in patients experiencing recurrent miscarriage with low levels of aPL. Key Points • This study challenges the conventional belief that only the higher antiphospholipid antibodies (aPL) titers directly correlated with worse pregnancy outcomes, which emphasized the importance of patients with low titer positive aPL-positive RM. • The results underscore the need for timely intervention in women with low titer aPL-positive RM, as it leads to favorable maternal-fetal outcomes.

"Non-criteria antiphospholipid antibodies": bridging the gap between seropositive and seronegative Antiphospholipid Syndrome

OBJECTIVE

We aimed to analyze the prevalence of non-criteria anti-phospholipid (aPL) antibodies and their role in the diagnosis, treatment and prognosis in a cohort of patients with clinical features consistent with a diagnosis of antiphospholipid syndrome (APS), but persistently negative for criteria aPL-anti-cardiolipin antibodies (aCL), anti-β2-glycoprotein I antibodies (aβ2-GPI), and lupus anticoagulant (LA) - named seronegative APS (SN-APS).

METHODS

Sera from SN-APS patients were tested for aCL by TLC-immunostaining, anti-vimentin/cardiolipin (aVim/CL) and anti-phosphatidylserine/prothrombin (anti-PS/PT) by ELISA. Control groups of our study were APS patients and healthy controls.

RESULTS

We enrolled 114 consecutive SN-APS patients, 69 (60.5%) resulted positive for at least one non-criteria test in two occasions 12 weeks apart. Among the persistently positive patients to these tests, 97% resulted positive for aCL by TLC-immunostaining, 52.3% for aVim/CL and 17.4% for aPS/PT. SN-APS patients with double positivity (aCL by TLC-immunostaining and aVim/CL) showed a likelihood positive ratio of 8 to present mixed thrombotic and obstetrical features. Among SN-APS patients tested positive, after the therapeutic changes, 3 cases of recurrent thrombosis were observed [median follow-up 41 months (IQR 39.5)]. Twenty pregnancies were recorded in 17 SN-APS patients after the detection of unconventional aPL and 12 of them (60%) experienced a good outcome under conventional treatment for APS.

CONCLUSIONS

This is the largest monocentric study demonstrating that aCL tested by TLC-immunostaining and aVim/CL can detect aPL positivity in SN-APS. It may encourage clinicians to monitoring and providing adequate targeted therapy, which improve SN-APS prognosis.

Does seronegative obstetric APS exist? "pro" and "cons"

Antiphospholipid Syndrome (APS) is the commonest treatable cause of recurrent miscarriage and pharmacological treatment of pregnant patients with antiphospholipid antibodies (aPL) should aim at preventing obstetric complications and maternal thrombotic events. Conventional treatment for patients with an established diagnosis of obstetric APS (OAPS), generally resulting in over 70-80% successful pregnancies. Since seropositive (SP)-APS and seronegative (SN)-APS patients had shown similar clinical profiles, patients with SN- OAPS, as well as SP-OAPS, should receive combined treatment in order to improve the pregnancy prognosis; indeed, current standard of care increased good pregnancy outcome in SN-APS, with similar effect to confirmed APS. The above data suggest that there are patients with the clinical manifestations of OAPS but persistently negative to conventional aPL that need to be identified to ensure adequate therapy and therefore a better prognosis. The clinical utility of non-criteria aPL in the diagnosis of SN-APS is still a matter of debate. In the last decade more and more studies have reported the presence of patients suffering from SN-APS in which non-conventional ("non-criteria") aPL might be present or antibodies may be detected using methodological approaches different from the traditional assays. To improve test standardization large prospective, multicenter, and multinational studies are needed. Therefore, when assessing a patient with clinical manifestations consistent with OAPS but aPL negative using the conventional available assays, the clinician should consider the possibility that the patient is affected with SN-APS.

Utility of Lupus Anticoagulant Assays (APTT-LA, KCT, DPT and DRVVT) in Detection of Antiphospholipid Syndrome (APS) in High Risk Pregnancy Cases

Routine investigation for recurrent pregnancy loss includes measurement of antiphospholipid antibodies. The lupus anticoagulant has long been associated with increased risks for thrombosis and adverse obstetric outcomes. But there are some disadvantages with lupus anticoagulant (LAC) tests which includes varied sensitivity of different clot based assays. ISTH recommends only 2 assays (preferably DRVVT and APTT-LA) for the identification of lupus anticoagulant but there are some studies which don't support this contention. Our study analyzed 526 samples from high risk pregnancy cases for APLA by all four LAC tests from tertiary centre of northern India. Among all the cases studies 65 cases were positive for lupus anticoagulant 25 of this became negative after 12 weeks. Among the 40 repeated positive assays, dRVVT could able to diagnose 36 cases followed by APTT-LA which could able to diagnose 28 cases, while KCT could able to diagnose 23 cases and dPT could able to diagnose only 14 cases. There were 12 cases in whom all lupus assays were positive. Our study thus concluded that DRVVT was the most sensitive followed by APPT-LA, KCT, dPT. The combination of dRVVT with APTT-LA or KCT appeared to be superior to other combinations. No individual test per se is 100% sensitive for the diagnosis of APLA in high risk pregnancy cases. Further results confirmed that repeated LAC result is required even in a high-risk setting. Positive LAC assay in majority were not associated with exclusively recurrent pregnancy loss but were associated with sporadic stillbirth and thrombosis.

Lupus anticoagulant testing using two parallel methods detects additional cases and predicts persistent positivity

Background:

Antiphospholipid antibody syndrome (APS) is characterized by laboratory evidence of antiphospholipid antibodies (aPL) [e.g. lupus anticoagulant (LA), anticardiolipin (ACL), and/or antiβ2-glycoprotein I (aB2GPI)] in a clinical setting of thrombosis or pregnancy morbidity. The International Society on Thrombosis and Haemostasis recommends two different testing modalities to detect LA. To evaluate these recommendations in a clinical setting, our hospital, a tertiary care center with a specialized coagulation laboratory, added the dilute Russell’s viper venom time to be performed in parallel with the PTT-lupus anticoagulant to detect LA.

Methods:

Results of aPL testing were collected on all patients who had LA testing for one year. Chart review was performed to correlate LA results with ACL, aB2GPI, and clinical history.

Results:

Patients who were initially LA positive by both PTT-lupus anticoagulant and dilute Russell’s viper venom time were more likely to be persistently positive. Patients who were positive for ACL and aB2GPI were likely to be positive by both LA methodologies. No single method was absolutely sensitive, as cases of APS were detected by PTTLA only, DRVVT only, and both methods.

Conclusions:

The addition of a second testing method for LA provides additional diagnostic information and may be helpful in stratifying risk of thrombosis.

A Monocentric Cohort of Obstetric Seronegative Anti-Phospholipid Syndrome

The present study was conducted to diagnose obstetric anti-phospholipid syndrome (OAPS) in patients with clinical signs suggestive of anti-phospholipid syndrome (APS), but persistently negative for conventional anti-phospholipid antibodies (aPL). Sera from 61 obstetrical seronegative APS (SN-APS) patients were analyzed for anti-cardiolipin antibodies (aCL) using thin-layer chromatography (TLC)-immunostaining, for anti-cardiolipin/vimentin antibodies (aCL/Vim), anti-phosphatidylserine/prothrombin antibodies, IgA anti-β₂glycoprotein I antibodies (aβ₂GPI), and IgA aCL antibodies by enzyme-linked immunosorbent assay. Taken together, our findings show that in 50 out of 61 SN-APS (81.9%) at least one aPL/cofactor antibody was detected using the assays under test. Results revealed that 76% of SN-APS patients resulted positive for aCL by TLC-immunostaining, 54% for aCL/Vim, 12% for aPS/PT, 4% for IgA aβ₂GPI, and 2% for IgA aCL. Thirty-five out of 61 patients were followed up and the tests were repeated on two occasions, at least 12 weeks apart. Twenty-six out of 35 SN-APS (74.3%) were positive at least one non-conventional test; only 2 patients (5.7%) did not confirm the positivity to the second test. These findings suggest that non-conventional tests, mainly aCL/Vim and aCL detected by TLC-immunostaining, seem to be the most sensitive approaches for finding out aPL in patients with obstetric SN-APS. The use of these tests can be useful for accurate and timely diagnosis of patients with obstetrical APS who are negative for conventional laboratory criteria markers.

Antiphospholipid syndrome and recurrent miscarriage: A systematic review and meta-analysis

Antiphospholipid syndrome (APS) is an autoimmune condition that is associated with thrombosis and morbidity in pregnancy. The exact mechanisms by which these associations occur appear to be heterogeneous and are not yet well understood. The aim of this study was to identify and analyze publications in recent years to better understand the diagnosis and its contribution to monitoring APS among women with recurrent miscarriage (RM). This systematic review and meta-analysis was conducted using the PubMed and Web of Knowledge databases, with articles published between 2010 and 2014, according to the PRISMA statement. Of the 85 identified studies, nine were selected. Most of the studies reported an association between recurrent miscarriage and specific antiphospholipid antibodies, as anticardiolipin antibodies (aCL), lupus anticoagulant (LA), anti-β2-glycoprotein I antibodies (aβ2GPI) and antiphosphatidylserine (aPS), which showed a relationship with RM. The main result of the meta-analysis revealed association between antiphospholipid antibodies (aPLs) and/or APS compared to the patients with RM (OR: 0.279; 95% CI: 0.212-0.366) and APS cases compared to the patients with RM (OR: 0.083; 95% CI: 0.036-0.189). High heterogeneity among these studies (I²=100.0%, p <0.001) was observed. In addition, there was no significant publication bias across studies according to Begg's test (p=0.230), although Egger's test (p=0.037) suggests significant publication bias. The funnel plot was slightly asymmetrical. Systematic review and meta-analysis demonstrated a positive association between antiphospholipid antibodies and/or antiphospholipid syndrome in patients with recurrent miscarriage.

Obstetric antiphospholipid syndrome: a recent classification for an old defined disorder

Obstetric antiphospholipid syndrome (APS) is now being recognized as a distinct entity from vascular APS. Pregnancy morbidity includes >3 consecutive and spontaneous early miscarriages before 10weeks of gestation; at least one unexplained fetal death after the 10th week of gestation of a morphologically normal fetus; a premature birth before the 34th week of gestation of a normal neonate due to eclampsia or severe pre-eclampsia or placental insufficiency. It is not well understood how antiphospholipid antibodies (aPLs), beyond their diagnostic and prognostic role, contribute to pregnancy manifestations. Indeed aPL-mediated thrombotic events cannot explain the obstetric manifestations and additional pathogenic mechanisms, such as a placental aPL mediated complement activation and a direct effect of aPLs on placental development, have been reported. Still debated is the possible association between aPLs and infertility and the effect of maternal autoantibodies on non-vascular manifestations in the babies. Combination of low dose aspirin and unfractionated or low molecular weight heparin is the effective treatment in most of the cases. However, pregnancy complications, in spite of this therapy, can occur in up to 20% of the patients. Novel alternative therapies able to abrogate the aPL pathogenic action either by interfering with aPL binding at the placental level or by inhibiting the aPL-mediated detrimental effect are under active investigation.

The lupus anticoagulant: results from 2257 patients attending a high-risk pregnancy clinic

Only 62 (2.7%) of 2257 high-risk patients tested positive for LAC over 6 years; only 5 (0.02%) with early recurrent miscarriage tested positive. The 2 assays recommended by ISTH guidelines were less effective than our 4-assay panel at capturing and describing LAC-positive patients.

When conventional treatment fails: the role of intravenous immunoglobulin in recurrent pregnancy loss secondary to antiphospholipid syndrome

Recurrent pregnancy loss (RPL) is a well-recognized complication of antiphospholipid syndrome (APS). First line therapy consists of low dose aspirin and heparin. Despite conventional therapy some women fail to achieve a successful pregnancy outcome. We describe the case of a patient who had two live births following intravenous immunoglobulin therapy despite previous failure with conventional therapy for RPL in the setting of APS. We will summarize the available literature on intravenous immunoglobulin for this indication.

[Antiphospholipid syndrome and pregnancy]

Antiphospholipid syndrome is characterized by arterial and venous thromboembolic events and persistent laboratory evidence of antiphospholipid antibodies. Obstetric complications such as recurrent miscarriage, early delivery, oligohydramnios, prematurity, intrauterine growth restriction, fetal distress, fetal or neonatal thrombosis, pre-eclampsia/eclampsia, and HELLP syndrome are also hallmarks of antiphospholipid syndrome. This syndrome is one of the diseases associated with the most severe thrombotic risk. Changes in the hemostatic system during normal pregnancy also result in a hypercoagulable state resulting in elevated thrombotic risk. Thromboembolic events are responsible of the vast majority of maternal and fetal deaths. Administration of appropriate thromboprophylaxis helps prevent thromboembolic complications during pregnancy in women with antiphospholipid syndrome and also give birth to healthy children. It is important to centralize the medication and management of these patients. It helps in the thoughtful care of these pregnant women encountering serious problems.

Uso de la heparina de bajo peso molecular y aspirina en una paciente con síndrome antifosfolípido y pérdida gestacional recurrente

Introducción: La pérdida gestacional recurrente (PGR) es una patología frecuente, que causa gran impacto en las parejas conllevando frustración, ansiedad, depresión, gastos excesivos y hasta rupturas de la relación de pareja. Su etiología es multicausal  y frecuentemente no se logra determinar. Se presenta el caso de una paciente con PGR quien luego de seis pérdidas gestacionales, en el séptimo embarazo se detectaron anticuerpos antifosfolípidos altos, recibiendo tratamiento de tromboprofilaxis doble hasta la semana 32, obteniéndose un producto pretérmino vivo y sano  que  evolucionó  satisfactoriamente.  Se  discuten dificultades para la precisión diagnóstica y las modalidades de tratamiento descritos. 

Antiphospohlipid syndrome in obstetrics

Antiphospholipid syndrome is characterised by a variety of clinical and immunological manifestations. The clinical hallmarks of this syndrome are thrombosis and poor obstetric outcomes, including miscarriages, fetal loss and severe pre-eclampsia. The main antiphospholipid antibodies include lupus anticoagulant, anticardiolipin and anti-β2-glycoprotein I. The combination of aspirin and heparin is considered the standard of care for women with antiphospholipid syndrome and embryo-fetal losses; however, aspirin in monotherapy may have a place in women with recurrent early miscarriage. A good benefit-risk ratio of low-molecular-weight heparin in pregnancy thrombosis treatment has been reported. Warfarin must be avoided if possible throughout the first trimester of pregnancy. Adequate pregnancy management of women with antiphospholipid syndrome should include co-ordinated medical-obstetrical care, a close follow-up protocol and a good neonatal unit. Close blood pressure control and early detection of proteinuria, together with Doppler studies of the utero-placental circulation should be included in the management protocol.

Managing pregnancy in inflammatory rheumatological diseases

Historically, pregnancy in women with many inflammatory rheumatic diseases was not considered safe and was discouraged. Combined care allows these pregnancies to be managed optimally, with the majority of outcomes being favorable. Disease activity at the time of conception and anti-phospholipid antibodies are responsible for most complications. Disease flares, pre-eclampsia, and thrombosis are the main maternal complications, whereas fetal loss and intrauterine growth restriction are the main fetal complications. Antirheumatic drugs used during pregnancy and lactation to control disease activity are corticosteroids, hydroxychloroquine, sulphasalzine, and azathioprine. Vaginal delivery is possible in most circumstances, with cesarean section being reserved for complications.