#4282 SARS-COV-2 VACCINATION AS A TRIGGER FOR AUTOIMMUNE GLOMERULOPATHIES, CHANCE OR REALITY?
Authors: Carrillo Jorge Ivan Zamora , Lopez Marina , Patricio Marc , Leon Juan Carlos , Garcia Sheila Bermejo , Pamplona Irene Agraz , Terrades Natàlia Ramos , Azancot Maria , Gaibor Néstor Toapanta , Romeo Maria José Soler 
Published: June 2023

Abstract

Background and Aims
The administration of vaccines, such as influenza or pneumococcus, is a known trigger for the appearance of autoimmune glomerulopathies (AIG). Since the start of vaccination against SARS-CoV-2, publications described the appearance of AIG after SARS-CoV-2 vaccine administration. The timing that has been stablished associated with causality reaches up to 6 weeks after vaccination. Our aim is to analyse the incidence of AIG flares before and after the start of vaccination against SARS-CoV-2 in our center.

Method
All persons with a kidney biopsy from January 2019 to March 2022 in our center were included in the study. We compared the incidence of AIG before and after Spanish vaccination (SV) initiation and determined the time-lapse from vaccine and SARS-CoV-2 infection to kidney biopsy. We established 6 weeks as the time limit to associate AIG with vaccine or SARS-CoV-2 infection. We also evaluated the analytical characteristics of the outbreaks. Idiopathic nephrotic syndrome (INS) which comprehended minimal change disease (MCD) and primary focal and segmental glomerulosclerosis (GSFS), IgA nephropathy (IgAN) and vasculitis were studied as subgroups. Minimal changes disease (MCD) flares in patients with and without kidney biopsy in that period were also studied

Results
A total of 386 biopsies were studied. Of them, 86/218(39.4%) were AIG performed pre- and 85/168(50.6%) post- national vaccination (p = 0.029). From the group with kidney biopsy after SV, 31 (36.5%) presented with acute renal failure or chronic kidney disease with acute exacerbation, peak of creatinine 3.09 mg/dL (IQ range: 2.01-4.97), serum albumin 3.5g/dL (IQ range: 2.9-3.9), proteinuria 1959mg/g (IQ range: 563-5558) and 53% with hematuria. The incidence of idiopathic nephrotic syndrome (INS) studied separately was also significantly higher post-SV (18-10.7%) than pre-SV (11-5.0%) (p = 0.036). There were no differences in the incidence of vasculitis or IgA nephropathy. Regarding time-lapse between either SARS-CoV-2 vaccine or infection to AIG diagnosis, a total of 17 (20%) took place in the first 6 weeks after SARS-CoV-2 vaccine and only 2 (2.4%) before 6 weeks after SARS-CoV-2 infection. Within those 17 flares, the most common diagnosis was of IgAN (5-29.4%), 14 (82.4%) received an mRNA vaccine and 9 (52.9%) took place after the 1st vaccine dose. We observed a significantly increase of MCD flares post-SV (n = 20) as compared with pre-SV (n = 13) (p = 0.002).

Conclusion
The incidence of AIG, INS and MCD flares in our center increased significantly after Spanish vaccination against SARS-CoV-2. Importantly, 20% of AIG flares took place in the first 6 weeks after receiving a vaccine dose, being the first dose the most risky one and IgAN the most frequent diagnosis. Although causality cannot be demonstrated solely with temporal association and general COVID-19 vaccination, further investigation and prospective studies could be of great interest.