Reduction of Bladder Volume after BCG Immunotherapy.

Bacillus Calmette-Guérin (BCG) immunotherapy is the most effective treatment for carcinoma in situ and high-risk non-muscle invasive bladder cancer (NMIBC). However, it can also provoke diverse side effects. We found 1 patient with a significantly and rapidly reduced bladder volume after the instillation of BCG. Few such cases and corresponding treatments have been reported. We speculated that the tuberculosis infection existed, so antitubercular therapy was given. After a 3-month oral intake of rifampicin, isoniazid, and ofloxacin, the volume of bladder returned to normal and the voiding symptoms disappeared. This case indicated that the reduction of bladder volume caused by BCG instillation could be treated with antitubercular therapy. Prompt and accurate diagnosis was important for the management.