Abstract: SA-OR80
Circulating Nephrin Autoantibodies Are Present in Almost 2/3 of Steroid-Naïve Pediatric Idiopathic Nephrotic Syndrome
Session Information
- Pediatric Nephrology: Clinical and Genetic Studies
November 04, 2023 | Location: Room 105, Pennsylvania Convention Center
Abstract Time: 04:48 PM - 04:57 PM
Category: Pediatric Nephrology
- 1900 Pediatric Nephrology
Authors
- Weins, Astrid, Brigham and Women's Hospital Department of Medicine, Boston, Massachusetts, United States
- Watts, Andrew James baxter, Brigham and Women's Hospital Department of Medicine, Boston, Massachusetts, United States
- Kamigaki, Yu, Nationwide Children's Hospital, Columbus, Ohio, United States
- Bowman, Nicole, Brigham and Women's Hospital Department of Medicine, Boston, Massachusetts, United States
- Dougherty, Julie, Nationwide Children's Hospital, Columbus, Ohio, United States
- Smoyer, William E., Nationwide Children's Hospital, Columbus, Ohio, United States
Background
Children who present with idiopathic nephrotic syndrome (INS) are initially treated with corticosteroids (CS) and do not routinely require a renal biopsy unless they have atypical features or subsequent resistance to CS. We recently identified circulating nephrin autoantibodies in approximately 30% of children and adults with biopsy proven MCD. As the majority of these patients had already received CS prior to serum sampling we hypothesized that this likely underestimated the true prevalence of pediatric nephrin autoantibody positive INS.
Methods
In this North American, multicenter, prospective study (via the Pediatric Nephrology Research consortium (PNRC)) we evaluated serum samples obtained from children at presentation and following GC monotherapy for nephrin autoantibodies by indirect ELISA. A threshold for positivity was determined from a healthy control cohort without renal disease. Patients received either no GC therapy (steroid naïve) or up to 2 days of GC therapy (minimal steroids) prior to the initial presentation sample. Patients were categorized into steroid sensitive (SSNS) and steroid resistant (SRNS) dependent on whether they achieved complete remission within 7 weeks of GC monotherapy.
Results
The median age was 4 years (IQR 3-11years) and 45% male. Almost two thirds, 63% (n=12/19) of steroid naïve INS patients were positive for nephrin autoantibodies at initial presentation and of those 75% (n=9/12) became negative following CS therapy. Including patients with minimal steroids prior to initial presentation revealed that 59% (n=17/29) were nephrin autoantibody positive. In those children who were steroid naïve at initial presentation, 69% (n=9/13) with SSNS were nephrin autoantibody positive compared with 50% (n=3/6) with SRNS.
Conclusion
We found that just under 2/3 of children with INS who were steroid naïve at initial presentation were serologically positive for nephrin autoantibodies. Furthermore, we identified nephrin autoantibodies in both SSNS and SRNS, and although the mechanism of GC in INS remains to be determined, B-cell targeted therapies are effective in treating some patients with SSNS and SRNS. This raises the possibility that nephrin autoantibodies may serve as an important biomarker to guide B cell targeted therapies in both SSNS and SRNS.
Funding
- Private Foundation Support