Severe diffuse proliferative bronchiolitis complicating culture-proven disseminated BCG infection after intravesical...

A man in his 70s was admitted to hospital following several months of dyspnoea, night sweats, weight loss and, latterly, fevers. His symptoms correlated with a second maintenance cycle of intravesical BCG instillation for superficial bladder cancer. Blood tests showed raised C-reactive protein, alkaline phosphatase and gamma-GT, although extensive further investigations did not reveal any specific cause. Treatment for a presumed diagnosis of disseminated BCG infection was started, following which his fevers ceased. Later available results of liver biopsy taken prior to treatment supported this diagnosis, and mycobacterial blood and urine cultures grew Mycobacterium bovis Recovery was complicated by a severe diffuse proliferative bronchiolitis which responded to corticosteroids. This case highlights an important dichotomy in the pathophysiology of disseminated BCG infection. It demonstrates how morbidity can be caused by both a direct dissemination of the organism and an immune hypersensitivity response in the same patient.