When the Treatment is the Cause: Disseminated Bacille Calmette-Guérin Infection

Bacille Calmette-Guérin (BCG) administration for superficial bladder cancer is a well-tolerated and very effective therapy. However, unpredictable systemic complications may occur on rare occasions. We present the case of a patient who attended for consultation because of fever, asthenia and weight loss following BCG immunotherapy. The clinical response to treatment and computed tomography scanning were key to diagnosis. Learning points It is essential to keep a high index of suspicion of possible, although uncommon, complications in patients treated with BCG immunotherapy.Response to treatment should always be evaluated to confirm diagnostic suspicion.