MO239: Clinical Evaluation of Immunological and Clinical Recurrence of Immune-Mediated Nephropathies after SARS-COV-2 Vaccine

Abstract

Abstract BACKGROUND AND AIMS The mass vaccination for COVID-19 has raised new concerns for patients with immune-mediated nephropathies: there is a small but growing literature of case-reports linking SARS-CoV-2 vaccines with heightened off-target immune responses leading to de novo or relapsing glomerular diseases [1, 2]. Aim of this study was to evaluate how many and how severe were the relapses of immune-mediated nephropathies after the SARS-CoV-2 vaccine in a single center. METHOD This is a retrospective study held in Italy from the start of the vaccination campaign (late December 2020) to December 31st 2021. We included all patients with an immune-mediated nephropathy (either on or off immunosuppressive therapy—IS), excluding patients with an end-stage renal disease or kidney transplant. In Italy we used mRNA (Comirnaty by Pfizer-BioNTech or Spikevax by Moderna) or adenoviral vector vaccines (Vaxzevria by AstraZeneca or Janssen), without any preference for patients with kidney disease, but those on active IS were given preferentially an mRNA vaccine. There was no active surveillance of lab tests after vaccination and post-vaccine tests were either concomitant to programmed visits or suggested on a patient by patient basis. Recurrence was defined as relapse of nephrotic or nephritic syndrome, doubling of urinary proteins with a max value > 1 g/24h, acute kidney injury with an active urinary sediment, or positivization or 5-fold increase of serological markers of disease activity (i.e.: ANCA in AAV). RESULTS A total of 38 patients (M: F 28:10, age at vaccine 45.9 ± 19.1 years) completed the vaccination protocol: among them, the most common nephropathy was membranous nephropathy (n = 12, 31.6%), followed by IgA nephropathy (n = 7, 18.4%), minimal change disease (n = 6, 15.8%) and ANCA-associated vasculitis (n = 6, 15.8%); 26 patients (68.4%) had at least one other comorbidity. We observed six relapses (4 MN, 1 IgA, 1 AAV), of which only one (MN) developed a mild oedema. The mean time from the first vaccine dose to the relapse was 101 ± 71 days (5–199 days) and only two episodes occurred within 4 weeks from a vaccine dose. We could not find an association between recurrences and maintenance IS at the time of vaccine or any other variable. The overall post-vaccine incidence rate of relapses was 35.8/100 patient-years, as compared with 14.0/100 patient-years historically observed in the same cohort [IRR 2.55, 95% confidence interval (CI) 0.89–5.97]. CONCLUSION Relapses of immune-mediated nephropathies are not common after SARS-CoV-2 vaccine and we did not observe any clinically relevant relapse. However the overall rate of relapse seems to be a little higher than prior vaccination [3], but only 2/6 patients recurred soon after a vaccine dose. As these relapses seem to be self-limiting, a post-vaccine monitoring could be useful in patients at high risk of severe disease.