Abstract: TH-PO0498
Multicenter Diagnostic Evaluation of a Novel Gd-IgA1 Chemiluminescent Immunoassay (CLIA) for Primary IgAN
Session Information
- Glomerular Diseases: Clinical, Outcomes, and Therapeutics Research - IgAN
October 22, 2026 | Location: Exhibit Hall A, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Glomerular Diseases
- 1402 Glomerular Diseases: Clinical, Outcomes, and Therapeutics
Authors
- Tong, Yiming, Shanghai Jiao Tong University Medical School Affiliated Ruijin Hospital, Shanghai, China
- Wang, Wei, Sichuan Academy of Medical Sciences and Sichuan People's Hospital, Chengdu, Sichuan, China
- Zhang, Junjun, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
- Xu, Jing, Shanghai Jiao Tong University Medical School Affiliated Ruijin Hospital, Shanghai, China
- Chen, Shasha, Sichuan Academy of Medical Sciences and Sichuan People's Hospital, Chengdu, Sichuan, China
- Dou, Yanna, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
- Hu, Xiaofan, Shanghai Jiao Tong University Medical School Affiliated Ruijin Hospital, Shanghai, China
- Ni, Liyan, Shanghai Jiao Tong University Medical School Affiliated Ruijin Hospital, Shanghai, China
- Wang, Ting, Shanghai Jiao Tong University Medical School Affiliated Ruijin Hospital, Shanghai, China
- Lei, Yuanzheng, Shanghai Jiao Tong University Medical School Affiliated Ruijin Hospital, Shanghai, China
- Ouyang, Yan, Shanghai Jiao Tong University Medical School Affiliated Ruijin Hospital, Shanghai, China
- Zhao, Zhanzheng, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
- Li, Guisen, Sichuan Academy of Medical Sciences and Sichuan People's Hospital, Chengdu, Sichuan, China
- Xie, Jingyuan, Shanghai Jiao Tong University Medical School Affiliated Ruijin Hospital, Shanghai, China
Background
Serum galactose-deficient IgA1 (Gd-IgA1) is a potential biomarker for IgA nephropathy (IgAN), but no standardized automated assay is clinically available.
Methods
A multicenter, blinded diagnostic accuracy study was conducted across three centers: Shanghai Ruijin Hospital (RJ, n=147), the First Affiliated Hospital of Zhengzhou University (ZU, n=120), and Sichuan Provincial People's Hospital (SC, n=126). Patients with suspected IgAN were enrolled before kidney biopsy; previously treated cases were excluded. High-specificity antibodies were generated via single B-cell sorting and B-cell receptor sequencing and developed into automated CLIA reagents. Serum Gd-IgA1 levels were compared between biopsy-confirmed primary IgAN and non-IgAN CKD controls. Diagnostic performance was assessed by receiver operating characteristic (ROC) analysis and compared with the KM55-based assay in the RJ cohort.
Results
Among 392 patients, 221 had primary IgAN and 171 had non-IgAN CKD. Median serum Gd-IgA1 was higher in primary IgAN than in non-IgAN CKD (21.60 vs. 14.19 U/mL). The overall ROC analysis yielded an AUC of 0.83 (95% CI: 0.79–0.87; Figure 1A). At a cutoff of 20 U/mL, sensitivity was 70.6%, specificity 93.0%, positive predictive value 92.9%, and negative predictive value 71.0%. Center-specific AUCs were 0.79 (RJ), 0.80 (ZU), and 0.89 (SC). In the RJ cohort, the CLIA kit showed a higher AUC than the KM55-based assay (0.80 [0.73–0.88] vs. 0.71 [0.62–0.79]; Figure 1B).
Conclusion
Serum Gd-IgA1 measured by the automated CLIA kit showed good discrimination for biopsy-confirmed primary IgAN across multiple centers and demonstrated superior performance compared with the KM55-based assay.
Funding
- Government Support – Non-U.S.