A 79-y-old man presented with systemic inflammatory response syndrome (SIRS) and jaundice, 6 h after the first intravesical instillation of bacillus Calmette-Guérin (BCG) for bladder cancer; he had a subsequent reaction 4 weeks later. Liver biopsy findings were compatible with BCG hepatitis. Anti-mycobacterial treatment induced complete recovery. The first episode probably represents a hypersensitivity reaction, whereas the latter course suggests BCG dissemination.