Introduction:
Nephrotic syndrome (NS) is a common glomerular disease in children. Podocytes play a crucial role in maintaining the glomerular filtration barrier, and disruptions in their function are central to the pathogenesis of nephrotic syndrome. Nephrin, a key transmembrane protein of the podocyte slit diaphragm, is essential for the structural integrity and function of the filtration barrier. Alteration in nephrin expression or function may contribute to the onset and progression of nephrotic syndrome. This study aimed to evaluate serum nephrin as a potential marker of disease activity and to determine its role in assessing the response to steroid therapy in children with idiopathic nephrotic syndrome.
Methods:
This prospective study included children aged 1 to 14 years diagnosed with the first episode of idiopathic NS. All the participants were steroid naive at the time of enrolment. Serum nephrin levels were measured using an ELISA kit (Human NPHN(Nephrin) ELISA Kit, Elabscience Biotechnology Co., Ltd, Wuhan, Hubei, China). The minimum detection range for human nephrin ranged from 0.16-10 ng/mL. Serum nephrin levels were measured at presentation and either at remission or after 42 days of steroid therapy if remission was not achieved. The study also assessed the role of nephrin levels in response to steroid therapy in NS. Participants were followed for the disease course duration of 2 years.
Results:
Forty-two children (64% boys) with first-episode idiopathic NS were enrolled. The median age (IQR) at enrolment was 48 (27-57) months, and the median age at disease onset was 47.5 (27-57) months. The mean follow-up duration was 22.9 (3.9) months. Among the participants, 13 (31%) did not have any relapse, 14 (33.3%) had infrequently relapsing nephrotic syndrome (IFRNS), 4 (9.5%) had frequently relapsing nephrotic syndrome (FRNS), 8 (19.1%) had steroid-dependent nephrotic syndrome (SDNS) and 3 (7.1%) had steroid-resistant nephrotic syndrome (SRNS) during follow-up. The median nephrin level at presentation was 0.04 (0.01-0.51) ng/ mL, which increased to 0.56 (0.15-1.62) ng/mL after steroid therapy, which was significant (p=0.01). At the 2-year follow-up, children with a favourable course of nephrotic syndrome (no relapse or IFRNS) had higher serum nephrin levels after steroid therapy compared to those with an unfavourable course (FRNS or SDNS). However, this difference was not statistically significant (p=0.29) owing to the small sample size of our study.
Conclusions:
Serum nephrin levels increase with steroid therapy in children with steroid-sensitive nephrotic syndrome, correlating clinically with the achievement of remission. Larger studies are needed to further investigate this correlation in children with FRNS and SDNS.
I have no potential conflict of interest to disclose.
I did not use generative AI and AI-assisted technologies in the writing process.