#5104 GLOMERULAR DISEASES ASSOCIATED WITH SARS-COV2 INFECTION AND VACCINATION: A MULTICENTRIC REGIONAL RETROSPECTIVE STUDY
Authors: Capaccio Flavia , Rossini Michele , Protopapa Paolo , Leo Vincenzo DI , Gilberti Marica , Gesualdo Loreto 
Published: June 2023

Abstract

Background and Aims
The SARS-CoV2 caused a pandemic disease, leading to millions of cases and fatalities worldwide. Kidney involvement is frequent and glomerular diseases (GD) have been reported in association with infection. Podocytopathies, endothelial injury with thrombotic microangiopathy are the most common histological findings in literature. From January 2021 anti SARS-CoV2 vaccination became available. Several GD has also been associated with vaccination. IgA nephropathy (IgAN) and minimal change disease (MCD) are the most common GD reported in patients who received vaccination. Our aim was to assess the histological findings in patients who presented kidney involvement after SARS-CoV2 infection and/or vaccination and to compare the frequencies of GD in these patients to those in non-Covid19 population.

Method
We conducted a retrospective study of kidney pathology in patients undergoing native kidney biopsy within 90 days of SARS-CoV2 infection and/or vaccination, between February 2020 and August 2022 in Apulia Region of Italy. We considered separately patients without history of urinary abnormalities and/or kidney dysfunction prior to infection and/or vaccination in order to detect GD which were more likely to be related to infection and/or vaccination than to pre-existent pathologies. We used a database of kidney biopsies performed in a period of 5 years (from January 2015 to February 2020) prior to the Covid19 pandemic as a control comparison cohort to examine glomerular diseases frequencies.

Results
Among the 808 biopsies: 36 (4.4%) were carried out within 90 days of SARS-CoV2 infection (Group 1) and 142 (17.6%) within 90 days of vaccination (Group2). Among them, we identified 12 patients with renal symptoms raised after COVID19 infection (Group 3) and 26 patients after vaccination (Group 4). In the Group 1 the main histological diagnosed founded were: podocytopathies (25.1%), IgAN (16.7%) and ANCA-vasculitis (13.9%). In Group 2, the most common histological diagnosis were IgAN (18.3%), podocytopathies (17%) and membranous nephropathy (MN) (10.6%). In the Group 3 we found a predominance of podocytopathies (33.3%) followed by ANCA-vasculitis and IgAN (three patients each, 25%). In the Group 4, the most frequent GD were podocytopathies (36.6%) followed by ANCA-vasculitis (19.2%) and IgAN (15.4%). Between the 1380 kidney biopsies from the 5 years pre-Covid19 period, the most frequent histological diagnosis were IgAN (18.3%), podocytopathies (18%) and MN (10.9%). Comparing Group 1 and Group 2 data with the 5 years pre-Covid19 database we found a significant increased prevalence only of ANCA vasculitis in group 1 (13.9% of patients after Covid19 infection vs 5.6% of pre-covid database (p-value: 0.03)). Comparing data from patients who had developed renal signs after Covid19 infection (group 3) and/or vaccination (group 4) with those in the 5 years database a significant higher prevalence of ANCA-related crescentic glomerulonephritis was found in both group. The 25% of patients of the Group 3 and the 19.2% of the Group 4 had a histological diagnosis of vasculitis, while these were found only in the 5.7% of patients from the pre-Covid19 database (p-value: 0.004 for Group 3 and 0.003 for Group 4). Furthermore podocytopathies in group 4 were significantly higher than pre-covid19 (36.6%vs18.3%, p = 0.02).

Conclusion
We found a higher prevalence of ANCA vasculitis and podocytopathies in patients with symptoms developed after SARS CoV2 infection/immunization compared to diagnosis prevalence in a pre-Covid19 reference database.