GROSS HEMATURIA AFTER COVID-19 mRNA VACCINATION: A PROSPECTIVE COHORT STUDY

ABSTRACT

Introduction: The effective control of coronavirus disease 2019 (COVID-19) can be achieved by implementing a global vaccination strategy. After millions of mRNA vaccines targeting severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) have been administered worldwide, several reports have shown the cases with gross hematuria (GH) following the mRNA vaccine against SARS-CoV2 in patients with glomerulonephritis, especially immunoglobulin A nephropathy (IgAN). A total of 22 articles including 36 cases of GH after COVID-19 vaccination as on July 31, 2022, were found in PubMed and Google Scholar databases. The most cases which had performed kidney biopsy were IgAN or IgA vasculitis. So, it suggested that GH after COVID-19 vaccination is rerated IgAN. Although there are many reported cases of IgAN after COVID-19 vaccination, the detailed clinical characteristics and outcome have not determined in these patients. Moreover, it remains unclear whether COVID-19 vaccination causes the new onset of nephritis or exacerbates pre-existing nephritis. To address this, herein, we conducted a prospective cohort study over a six-month period. Method(s) We analyzed 82 patients who presented with GH after COVID-19 vaccination and conducted a 6-month observational study. Patients, 18 years or older, who presented to the hospital with GH after COVID-19 vaccination were recruited. All the patients visited either Juntendo University Hospital or Juntendo University Urayasu Hospital between May 11, 2021, and July 31, 2022. Result(s) During the study period, a total of 82 individuals who presented with GH after COVID-19 vaccination were enrolled. The median age of the patients was 38 years;58 cases (70.7%) were females. All the patients received an mRNA COVID-19 vaccine. Most patients showed GH within three days after the second or third dose. Among the 82 patients, 22 had been already diagnosed with IgAN or IgA vasculitis (IgAV) before vaccination, and 45 of the 60 undiagnosed patients had a history of abnormal urinary findings. We performed kidney biopsies on 42 of the 60 undiagnosed patients, who were then diagnosed with IgAN (N=41) or IgAV (N=1). Pathological findings demonstrated that chronic inflammation of glomeruli, such as the expansion of mesangial matrix and glomerular sclerosis, is similarly observed in these newly diagnosed patients compared to patients with IgAN unrelated to vaccination. Finally, we evaluated the levels of biomarkers known to be elevated in IgAN at diagnosis during the course of the study and found that they did not increase. Notably, only few cases showed a slight increase in the level of serum creatinine, and no patients progressed to severe renal dysfunction. Conclusion(s) Present prospective study with 82 cases with GH after COVID-19 vaccination have identified their clinical characteristics and outcome. Furthermore, the acute manifestation of vaccine-induced GH may have highlighted the high prevalence of undiagnosed or preclinical IgAN in Japan. No conflict of interestCopyright © 2023