Abstract: PO1536
Anti-Phospholipase A2 Receptor Antibody Levels in Asian Patients with Primary Membranous Nephropathy: A Territory-Wide Study
Session Information
- Glomerular Diseases: Clinical Features and Outcomes in Nephrotic Syndromes and Complement-Mediated Diseases
November 04, 2021 | Location: On-Demand, Virtual Only
Abstract Time: 10:00 AM - 12:00 PM
Category: Glomerular Diseases
- 1203 Glomerular Diseases: Clinical, Outcomes, and Trials
Authors
- Yap, Desmond Yat Hin, University of Hong Kong, Hong Kong, Hong Kong
- Yam, Irene, University of Hong Kong, Hong Kong, Hong Kong
- Lam, Michelle, University of Hong Kong, Hong Kong, Hong Kong
- Bisnauthsing, Hemlata, University of Hong Kong, Hong Kong, Hong Kong
- Chan, Tak Mao Daniel, University of Hong Kong, Hong Kong, Hong Kong
Background
Different cut-off values of anti-phospholipase A2 receptor (anti-PLA2R) antibody for differentiating between primary membranous nephropathy (PMN) and secondary membranous nephropathy have been reported. The optimal anti-PLA2R levels to reflect disease activity states in Asian patients with PMN remain undefined.
Methods
We conducted a territory-wide study in Hong Kong to investigate the serum anti-PLA2R levels in Chinese patients with PMN during 2017-2020. Anti-PLA2R levels were measured by commercial ELISA kits (EuroImmun, Germany) in serum samples collected from biopsy-confirmed PMN patients during active disease or remission, and their predictive values for active PMN were evaluated.
Results
Forty hundred and six serum samples from 320 PMN patients were analysed. 319 samples were obtained during active disease and 87 during disease remission. Anti-PLA2R titres during active disease were significantly higher than that during remission (95.1±235.0 RU/mL vs. 1.9±3.9 RU/ml respectively, p<0.001). Using 20 RU/ml as cut-off, the sensitivity (SN) and specificity (SP) for predicting active disease were 39% and 98% respectively [AUC 0.68, p<0.001; positive predictive value (PPV) and negative predictive value (NPV) were 98% and 30% respectively]. Using 10 RU/mL as cut-off, the SN and SP for diagnosing active PMN were 46% and 95% respectively [AUC=0.71, p<0.001; PPV and NPV were 97% and 32% respectively]. Anti-PLA2R titres correlated with urine protein-to-creatinine ratio and 24-hr urine protein levels (r= 0.32 and 0.37 respectively, p<0.001 and <0.001).
Conclusion
Anti-PLA2R showed good SP and PPV prediction for active PMN in Chinese patients, and correlated with severity of proteinuria. A lower threshold (≥10 RU/mL) may show improved SN for predicting active PMN in Asian patients.
