Back pain following instillations of BCG for superficial bladder cancer is not a reactive complication: review of 30 Mycobacterium bovis BCG vertebral osteomyelitis cases

Mycobacterium bovis Bacillus Calmette-Guérin (BCG) instillations are used in bladder cancer treatment. Adverse effects can occur. Osteoarticular complications are mainly reactive arthritis, but true infections have been described, such as vertebral osteomyelitis. We made a review of M. bovis BCG vertebral osteomyelitis after instillations for bladder cancer using PubMed search. We added three new French cases. Twenty-seven cases of BCG vertebral osteomyelitis had been reported on PubMed. Of the 30 cases, all were male, averaging 73.4 ± 8.7 years old. Median time between diagnosis and first and last instillation was 22.5 and 14 months respectively. Half of vertebral osteomyelitis was thoracic and lumbar in the other half. Sensitivo-motor deficit was present at diagnosis in 42% of cases. Other infectious locations were common, mainly infectious abdominal aortic aneurysms (20%). Rifampicin, ethambutol and isoniazid were the usual therapy. Poor outcomes were reported with 50% of one or more spine surgery. M. bovis BCG vertebral osteomyelitis following bladder instillation for bladder cancer is a rare complication. However, the late onset of back pain after instillations differentiates them from reactive arthritis. Concomitant septic location such as infectious abdominal aortic aneurysms must be known.