Acute interstitial nephritis following SARS-CoV-2 virus vaccination.

A number of reports have described new onset or relapse of existing glomerular disease after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination. More and more of these cases continue to emerge, and the European Medicines Agency (EMA) has recently launched an in-depth investigation to ascertain the true frequency of such renal side effects. In comparison, acute interstitial nephritis after SARS-CoV-2 vaccination has only been described in 1 solitary case. Here, we describe a case of acute kidney injury due to biopsy-proven acute interstitial nephritis soon after SARS-CoV-2 vaccination with the Astra-Zeneca vaccine. The patient responded well to steroids, although he required temporary renal replacement therapy. A thorough medical history failed to elucidate any plausible explanation or trigger other than the preceding vaccination. We acknowledge the possibility that other factors could have triggered acute interstitial nephritis in the case described here. Similar uncertainty exists regarding glomerular disease reported in conjunction with SARS-CoV-2 vaccination. However, we note that acute interstitial nephritis associated with vaccination has been described before the pandemic, and we therefore feel that a link is possible. We suggest that nephrologists should be vigilant when they see cases of unexplained acute interstitial nephritis. A history of preceding SARS-CoV-2 vaccination should be explored, and cases should be reported within national systems of pharmacovigilance.