Infected aortic aneurysm caused by Mycobacterium bovis after intravesical Bacillus Calmette-Guérin treatment for bladder cancer

A 70-year-old man presented with lower back pain and cyanotic changes in his left lower extremity. He was diagnosed with infected aortic aneurysm and infectious spondylitis. He had received intravesical Bacillus Calmette-Guérin (BCG) therapy up to 1 month before the onset of symptoms. The aneurysm was excised and an aorto-biiliac interposition graft was performed. Mycobacterium tuberculosis complex was cultured in the surgical specimens. Real-time polymerase chain reaction (PCR) targeting the senX3-regX3 region, and multiplex PCR using dual-priming oligonucleotide primers targeting the RD1 gene, revealed that the organism isolated was Mycobacterium bovis BCG. The patient took anti-tuberculosis medication for 1 year, and there was no evidence of recurrence at 18 months follow-up.