Anti-phospholipid antibodies nephropathy is associated with an increased risk of kidney failure: a systematic literature review and meta-analysis.

Background: Anti-phospholipid antibodies nephropathy (aPL-N) is a complex feature of anti-phospholipid syndrome due to microvascular lesions. Renal prognosis and predictors of outcome are not yet known.

Methods: We performed a systematic review of the literature (February 2006-January 2024) using the PubMed, Scopus, Cochrane Library and EMBASE databases. Two reviewers independently conducted literature screening and data extraction in a blinded, standardized manner. A random effects model was used to pool odds ratios (ORs) [with 95% confidence interval (CI)] for the primary analysis, the risk of kidney failure. Subgroup analyses were performed for clinical and laboratory features that predicted renal outcomes. Heterogeneity was assessed by I².

Results: Six records involving 709 patients were included in the meta-analysis. Biopsy-proven aPL-N was found in 238/832 (28.6%) patients. Acute kidney injury (AKI) was present at diagnosis in 20/65 (30.8%), while 73/233 (31.3%) patients with aPL-N developed chronic kidney disease (CKD)/end-stage kidney disease (ESKD) at follow-up. aPL-N was associated with an increased risk of CKD/ESKD [OR 6.89 (95% CI 2.42-19.58)] and AKI [OR 2.97 (95% CI 1-4-6.29)]. Arterial hypertension and positivity for lupus anticoagulant, anti-cardiolipin antibodies and anti-β2 glycoprotein I antibodies were associated with an increased risk of developing aPL-N [OR 3.7 (95% CI 1.9-7.23), OR 4.01 (95% CI 1.88-8.53), OR 2.35 (95% CI 1.31-4.21) and OR 19.2 (95% CI 2.91-125.75), respectively].

Conclusion: aPL-N is associated with poor renal outcomes. High blood pressure and aPL positivity have been identified as predictors of adverse renal outcomes. This up-to-date knowledge on renal outcomes and predictors of renal outcomes in aPL-N enables a personalized follow-up and therapeutic approach.