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

Early Prediction of Adverse Pregnancy Outcome in Women with Systemic Lupus Erythematosus, Antiphospholipid Syndrome, or Non-Criteria Obstetric Antiphospholipid Syndrome

A prospectively study of pregnant women with systemic lupus erythematosus (SLE), antiphospholipid syndrome, or non-criteria obstetric antiphospholipid syndrome was conducted to describe the characteristics of women followed in a referral unit and to derive a predictive tool for adverse pregnancy outcome (APO). Demographic characteristics, treatments, SLE activity, and flares were recorded. Laboratory data included a complete blood cell count, protein-to-creatinine urinary ratio (Pr/Cr ratio), complement, anti dsDNA, anti-SSA/Ro, anti-SSB/La, and antiphospholipid antibodies status. A stepwise regression was used to identify baseline characteristics available before pregnancy and during the 1st trimester that were most predictive of APO and to create the predictive model. A total of 217 pregnancies were included. One or more APO occurred in 45 (20.7%) women. A baseline model including non-Caucasian ethnicity (OR 2.78; 95% CI [1.16-6.62]), smoking (OR 4.43; 95% CI [1.74-11.29]), pregestational hypertension (OR 16.13; 95% CI [4.06-64.02]), and pregestational corticosteroids treatment OR 2.98; 95% CI [1.30-6.87]) yielded an AUC of 0.78 (95% CI, [0.70-0.86]). Among first-trimester parameters, only Pr/Cr ratio improved the model fit, but the predictive performance was not significantly improved (AUC of 0.78 vs. 0.81; p = 0.16). Better biomarkers need to be developed to efficiently stratify pregnant women with the most common autoimmune diseases.

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.

Determination of Thrombogenicity Levels of Various Antiphospholipid Antibodies by a Modified Thrombin Generation Assay in Patients with Suspected Antiphospholipid Syndrome

Antiphospholipid syndrome (APS) is a hypercoagulable state accompanied by the presence of heterogeneous antiphospholipid antibodies (aPL), which nonspecifically affect hemostasis by the presence of lupus anticoagulans (LA), anticardiolipin antibodies (aCL), antibodies against β2-glycoprotein-I (anti-β2GPI), but also non-criteria antibodies such as antibodies against β2-glycoprotein-I domain I (anti-DI), anti-phosphatidylserine/prothrombin (anti-PS/PT), anti-annexin V, and many others. The main target of the antibodies is the activated protein C (APC) system, the elimination of which can manifest itself as a thrombotic complication. The aim of this study was to determine the thrombogenicity of antibodies using a modified protein C-activated thrombin generation assay (TGA) on a group of 175 samples suspected of APS. TGA was measured with/without APC and the ratio of both measurements was evaluated (as for APC resistance), where a cut-off was calculated ≤4.5 (90th percentile) using 21 patients with heterozygous factor V Leiden mutation (FV Leiden heterozygous). Our study demonstrates the well-known fact that multiple positivity of different aPLs is a more severe risk for thrombosis than single positivity. Of the single antibody positivity, LA antibodies are the most serious (p value < 0.01), followed by aCL and their subgroup anti-DI (p value < 0.05). Non-criteria antibodies anti-annexin V and anti-PT/PS has a similar frequency occurrence of thrombogenicity as LA antibodies but without statistical significance or anti-β2GPI1 positivity. The modified TGA test can help us identify patients in all groups who are also at risk for recurrent thrombotic and pregnancy complications; thus, long-term prophylactic treatment is appropriate. For this reason, it is proving increasingly beneficial to include the determination antibodies in combination with modified TGA test.

Pregnancy-related complications in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a systemic autoimmune inflammatory disease that predominantly affects women of childbearing age and results in various adverse pregnancy outcomes (APOs). Pregnancy was formerly discouraged in patients with SLE because of unstable disease activity during the gestation period, increased thrombosis risk, severe organ damage, and inevitable side effects of immunosuppressive agents. Currently, most patients with SLE have successful pregnancies due to preconception counselling, strict monitoring, and improved therapy with minimised complications for both the mother and foetus. Hydroxychloroquine (HCQ) is extensively used and is beneficial for improving pregnancy outcomes. However, pregnant women with SLE have a high-risk of APOs, such as disease flare, preterm birth, intrauterine growth restriction (IUGR), preeclampsia, and pregnancy loss. Better understanding of the changes in maternal immunity and serum biomarkers, as well as their relationships with SLE-related APOs progression, would facilitate the investigation of molecular mechanisms for triggering and ameliorating APOs. Furthermore, it would enable us to explore and develop novel and effective therapeutic strategies to prevent disease activation. Therefore, this review briefly introduces the interaction between pregnancy outcomes and SLE, elucidates pathophysiological and immunological changes during SLE pregnancy. Furthermore, this review systematically expounds on the effective predictors of APOs and the molecular mechanisms underlying the SLE-related APOs to provide a solid foundation for the advanced management of lupus pregnancy.