Acute tubulointerstitial nephritis induced by intravesical bacillus Calmette-Guerin: a rare case of acute kidney injury.

Intravesical bacillus Calmette-Guerin (IVBCG) is considered the most optimal follow-up therapy for high-risk urothelial cancers. Although side effects such as cystitis, hematuria, and low-grade fever are common, they are generally mild. Severe reactions involving the kidneys are extremely rare. Here, we present the case of a 64-year-old male who developed acute renal failure due to acute tubulointerstitial nephritis (ATIN) following the first IVBCG administration. We have also conducted a literature review concerning IVBCG-induced nephritis.