Anti-phospholipase A2 receptor positive membranous nephropathy: investigating the link between electron microscopy stages and clinical outcome

ABSTRACT

This retrospective, observational study sought to examine the relationship between Ehrenreich-Churg electron microscopy (EM) stages and long-term outcomes in anti-PLA2R membranous nephropathy (MN). Seventy-one patients with anti-PLA2R MN (median titer 185.7RU/mL) were followed for a median of 46 months, with end-stage kidney disease (ESKD) as the primary endpoint, and response to treatment as a secondary endpoint. Patients were grouped into stages I-II (41 patients) and stages III-IV (30 patients) for analytical purposes. Notably, the III-IV group demonstrated a lower eGFR, lower anti-PLA2R titer, but a higher chronicity score. Kaplan-Meier analysis showed shorter mean kidney survival time in stages III-IV compared to I-II (p 0.03). However, multivariate analysis using Cox regression indicated that Ehrenreich-Churg stages did not significantly influence kidney survival, but lower eGFR at diagnosis and higher histopathological chronicity score did. Remission was achieved by 64% of patients and no relationship between Ehrenreich-Churg stages and treatment response was found. The only identified risk factor for not achieving remission was the severity of hyposerinemia at diagnosis. In conclusion, while EM stages III-IV are associated with more chronic lesions and stages I-II with more active immunologic disease, the histological chronicity score seems to be a stronger predictor of long-term outcomes.

KEYWORDS:

• Anti-PLA2R membranous nephropathy
• ehrenreich-churg stages of membranous nephropathy
• electron microscopy
• end-stage kidney disease

Disclosure statement

No potential conflict of interest was reported by the author(s).

The results presented in this paper have not been published previously in whole or part, except in abstract format.

Authors’ contributions

G.S., S.S. responsible for conceptualization, methodology and original draft preparation. G.T.B., N.P. pathology assessment and data recording; S.C, A.Z. carried out bibliographic research and data recording. G.S., S.S. performed the statistical analysis. All authors contributed to clinical care of patients, commented on previous versions of the manuscript, and read and approved the final manuscript.

Data availability statement

The data underlying this article will be shared on reasonable request to the corresponding author.

Additional information

Funding

The author(s) reported there is no funding associated with the work featured in this article.