Double-Positive Anti-Glomerular Basement Membrane Antibody and Myeloperoxidase Antineutrophil Cytoplasmic Autoantibody-Associated Glomerulonephritis Post COVID-19 mRNA vaccine: A Case Series of 4 Patients.

This case series reinforces growing evidence that COVID-19 mRNA vaccine-induced glomerulonephritis is a rare but real phenomenon. Dual ANCA and anti-GBM nephritis can present after the first dose of COVID-19 mRNA vaccine or after several administrations of the vaccine. We are the first to report cases of double-positive MPO ANCA and anti-GBM nephritis after Pfizer-BioNTech vaccination. To our knowledge, we are also the first to report outcomes of repeat COVID-19 vaccination in patients with de novo flare of ANCA and anti-GBM nephritis temporally associated with COVID-19 vaccination.