Antiphospholipid antibodies in end-stage renal disease: A systematic review and meta-analysis

Assessment of Arteriovenous Fistula Maturation in Hemodialysis Patients with Persistently Positive Antiphospholipid Antibody: A Prospective Observational Cohort Study

BACKGROUND

Arteriovenous fistula (AVF) is the preferred vascular access option for hemodialysis (HD). The latter requires a remodeling process called maturation that can take up to 3 months. Maturation failure is a frequent complication associated with significant morbidity. The prevalence of antiphospholipid antibody (aPL) positivity in HD patients is high and may result in thrombosis of the vascular access. Recently, aPL persistent positivity has been associated with AVF maturation failure in a retrospective study including 116 patients.

METHODS

We are conducting an observational prospective cohort study aiming to evaluate this association. Included patients are planned for AVF creation, aged over 18 years old, and have an interpretable aPL assay confirmed at 12 weeks and without any other innate or acquired thrombophilia or inflammatory disease. Primary endpoints will be the evaluation of AVF maturation clinically and by ultrasound. Secondary endpoints will focus on clinical outcomes other than AVF maturation (i.e., primary patency, thrombosis or stenosis, bleeding and hemodialysis adequacy parameters).

CONCLUSIONS

This prospective observational cohort study aims to examine the possibly causative link between aPL persistent positivity and AVF maturation failure. This study was registered on ClinicalTrials.gov (ID number: NCT06112821).

Antiphospholipid antibodies positivity as a potential risk factor for restenosis following arteriovenous fistula stenting in hemodialysis patients: a pilot study

Background

The arteriovenous fistula (AVF) is the preferred vascular access for hemodialysis. AVF stenosis is a common complication, often requiring balloon angioplasty. For recurrent stenosis, AVF stenting may be an option. Persistent antiphospholipid antibody (aPL) positivity is frequently observed in hemodialysis (HD) patients and is associated with AVF thrombosis and stenosis. This study aimed to evaluate AVF stent survival without stenosis in aPL-positive hemodialysis patients.

Methods

A monocentric retrospective observational study was conducted on 35 patients who underwent AVF stenting between 1st January 2014 and 31st December 2023. The patients were divided into two groups: the aPL+ group [defined by a score of 3 or more based on the laboratory criteria of the 2023 ACR/EULAR for antiphospholipid syndrome (APS)] and the control group. Intrastent restenosis was defined as a chronic change in the AVFphysical examination or blood flow, confirmed by ultrasound (US) or angiography. Kaplan-Meier survival analysis was used to estimate the probability of stent survival without restenosis.

Results

The prevalence of intrastent restenosis was significantly higher in the aPL+ group at 24 months. The Kaplan-Meier survival analysis showed a significantly lower probability of AVF stent survival without restenosis in the aPL+ group (age-adjusted Hazard Ratio, 2.13 [IC95%, 1.70-2.69]).

Conclusion

To the best of our knowledge, we describe for the first time a statistically significant association between aPL+ and AVF intrastent restenosis. Intimal hyperplasia is a non-thrombotic lesion associated with aPL+ and is linked to the mammalian target of rapamycin (mTOR) signaling pathway. We hypothesize that aPL may contribute to intrastent restenosis by inducing intimal hyperplasia. Whether this phenomenon is mTOR-mediated and whether sirolimus-eluting stents or balloons could be a better option for aPL+ patients requires further study.

Antiphospholipid antibody positivity is associated with maturation failure and thrombosis of native arteriovenous fistula: a retrospective study in HD patients

Background and hypothesis

The prevalence of antiphospholipid antibody (aPL) is high among hemodialysis (HD) patients compared to the general population and is inconsistently associated with arteriovenous fistula (AVF) thrombosis or stenosis. The association with maturation failure has never been investigated. This study aims to evaluate native AVF complications (thrombosis, stenosis, and maturation failure) and primary patency in aPL positive HD patients.

Methods

We retrospectively identified 116 HD patients with native AVF. We collected the aPL profiles, the clinical and biological data potentially involved in AVF maturation failure, thrombosis, and stenosis, and investigated the association of these complications and aPL positivity. Kaplan-Meier survival analysis was performed.

Results

In our cohort, the prevalence of aPL persistent positivity was 32.7% and this was strongly associated with AVF maturation failure defined by ultrasound. aPL persistent positivity was a strong predictor in multivariate analysis and this association was independent of AVF stenosis or thrombosis during maturation process. There was no association with primary and functional primary patency, and stenosis. However, aPL persistent positivity according to ACR/EULAR classification criteria was associated with thrombosis when compared to strictly negative aPL patients.

Conclusions

In our cohort, aPL persistent positivity was significantly associated with AVF maturation failure and thrombosis but not with AVF stenosis. To our knowledge, we report for the first time, a statistically significant association between aPL positivity and delay or absence of native AVF maturation.

Antiphospholipid Antibodies Associated with Native Arteriovenous Fistula Complications in Hemodialysis Patients: A Comprehensive Review of the Literature

Antiphospholipid antibody (aPL)-persistent positivity is frequent in hemodialysis (HD) patients. Native arteriovenous fistula (AVF) complications such as stenosis and thrombosis are among the most important causes of morbidity and mortality in hemodialysis patients. The association between aPL positivity and AVF thrombosis seems to now be well established. However, whether aPL positivity is associated with other AVF complications, such as maturation failure or stenosis, is not well known. Given the significant impact of AVF failure on patient's prognosis, it is of interest to further investigate this particular point in order to improve prevention, surveillance and treatment, and, ultimately, the patient's outcome. This literature review aims to report the recent literature on aPL-associated native AVF complications.

Frequent vascular access thrombosis in a patient with end stage kidney disease on hemodialysis

Vascular access thrombosis (VAT) is common among patients receiving hemodialysis and leads to missed dialysis treatments, hospitalizations, catheter placement, and graft/fistula abandonment. This article reviews the association between hypercoagulability and VAT and the high prevalence of hypercoagulable states in end-stage kidney disease (ESKD). This article reviews the role of antithrombotic and anticoagulant medications in preventing VAT. The article concludes by reviewing the unique challenges of using vitamin K antagonists in patients with ESKD.