Introduction:
Anti-nephrin autoantibodies have been discovered in patients with minimal change disease (MCD) and primary focal segmental glomerulosclerosis (FSGS), especially in those with active nephrotic syndrome. This study investigates the prevalence and clinical significance of anti-nephrin antibodies in adult Chinese patients.
Methods:
We enrolled a retrospective cohort (313 MCD, 118 primary FSGS) diagnosed by kidney biopsy and followed for more than six months. Plasma was collected at biopsy and stored at -80°C. A cross-sectional cohort (123 MCD, 42 primary FSGS) was tested with fresh samples. Anti-nephrin IgG and IgM were measured using ELISA. Clinical data were collected and analyzed.
Results:
Among all patients, 49.9% was positive for anti-nephrin antibodies, including 25.8% for IgG, 36.9% for IgM, and 12.8% for both. The rates were comparable between stored and fresh samples but higher in patients with nephrotic-range proteinuria not receiving steroids or immunosuppressants. Patients with positive anti-nephrin antibodies exhibited higher proteinuria, lower eGFR, similar clinical remission rates but significantly higher relapse rates, compared to those without antibodies. Longitudinal analysis showed close correlations between urinary protein and antibody levels. Clinical features were comparable between IgG and IgM. Patients with both antibodies exhibited the most severe proteinuria and highest relapse frequency. IgG/IgM deposits in glomeruli correspond with anti-nephrin IgG/IgM, showing co-localization with nephrin.
Conclusions:
Anti-nephrin antibodies, including IgG and IgM, are detectable in adult patients with MCD and primary FSGS and are associated with active nephrotic syndrome and frequent relapse. These antibodies may serve as valuable biomarkers and potential therapeutic targets.
I have no potential conflict of interest to disclose.
I did not use generative AI and AI-assisted technologies in the writing process.