Abstract: FR-PO912
Clinical Characteristics of Anti-Nephrin Autoantibody-Positive Minimal Change Disease in Adults: A Case Series in Elderly Japanese
Session Information
- Geriatric Nephrology
November 03, 2023 | Location: Exhibit Hall, Pennsylvania Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Geriatric Nephrology
- 1300 Geriatric Nephrology
Authors
- Fujita, Yoko, St. Marianna University School of Medicine, Kawasaki, Japan
- Watts, Andrew James baxter, Brigham and Women’s Hospital, Boston, Massachusetts, United States
- Ichikawa, Daisuke, St. Marianna University School of Medicine, Kawasaki, Japan
- Shibagaki, Yugo, St. Marianna University School of Medicine, Kawasaki, Japan
- Suzuki, Tomo, Kameda Medical Center, Kamogawa, Chiba, Japan
- Keller, Keith H., Brigham and Women’s Hospital, Boston, Massachusetts, United States
- Weins, Astrid, Brigham and Women’s Hospital, Boston, Massachusetts, United States
- Murakami, Naoka, Brigham and Women’s Hospital, Boston, Massachusetts, United States
Background
Minimal change disease (MCD) is a leading cause of nephrotic syndrome in adults and is more common in the Japanese population. Recently, nephrin autoantibodies were reported in a North American Cohort of adults and children with MCD supporting an autoantibody mediated etiology. However, the clinical characteristics of nephrin autoantibody positive MCD in elderly Japanese patients have scarcely been studied.
Methods
In this single-center case series in Japan, we included 8 consecutive adult cases of biopsy-proven MCD presented to our center in 2021. We evaluated serum, obtained at presentation and following treatment, for circulating nephrin autoantibodies by indirect ELISA. The renal biopsies were evaluated for punctate IgG deposition and co-localization with nephrin by immunofluorescence confocal microscopy imaging.
Results
The median age was 75 years (range 56-84), 43% male, median creatinine and median urine protein/creatinine ratio at diagnosis were 0.92 mg/dL (range 0.47-4.5) and 10.9 g/g (range 7.7-14.0 g/gCr) respectively. Five out of eight cases (63%) had circulating anti-nephrin autoantibodies at presentation and this correlated completely with “punctate IgG” that colocalized with nephrin in the renal biopsies of all positive patients. All 8 patients achieved complete remission after therapy and those with serum anti-nephrin antibodies had reduction in antibody titer with clinical response (Figure). Anti-nephrin antibody positive group had shorter relapse-free time (median 16.5 months), compared to negative group (no relapse).
Conclusion
In our cohort of anti-nephrin antibody-positive adult Japanese MCD cases in elderly Japanese patients, we observed the correlation of anti-nephrin antibody titer with disease activity and shorter relapse-free time. Larger studies are needed to further characterize anti-nephrin antibody positive MCD cases in adults.