Late onset granulomatous interstitial nephritis after booster dose of COVID-19 vaccination: Case report and review of literature

Billions of doses of COVID-19 vaccine have been administered to combat the coronavirus pandemic. Though the vaccine is generally well tolerated, several cases of new onset or relapsing glomerulonephritis have been reported. In comparison, post-vaccination tubulointerstitial nephritis (TIN) has rarely been reported, mostly after the first or the second dose of the vaccine. Acute interstitial nephritis after booster dose of COVID-19 vaccination has not yet been reported. We report a case of acute granulomatous TIN shortly after the booster dose of Moderna vaccine. Our patient had no clinical evidence of renal injury after the first two doses of vaccine. Renal dysfunction was incidentally observed ~ 1 month after the booster dose of vaccine. The patient responded to steroids with rapid improvement in kidney function. While it is difficult to ascertain the causal relationship between the vaccination and development of TIN, it is important to be vigilant about such delayed side effects of the vaccine.