Acute respiratory failure and septic shock induced by Mycobacterium bovis. A rare side effect of intravesical BCG therapy

INTRODUCTION: Intravesical bacillus Calmette-Guerin (BCG) therapy, recommended for superficial bladder tumors, triggers side effects in fewer than 5% of patients. The most severe side effects, however, are septic shock and acute respiratory failure. CASE: A 70-year-old man was hospitalized for septic shock with acute respiratory and renal failure after intravesical instillation of BCG, which was identified in the gastric aspiration sample. Treatment with rifampicin, ethambutol, isoniazid, and corticosteroid therapy, as well as standard reanimation measures, led to the patient's recovery. DISCUSSION: This case shows the potentially severe side effects of intravesical BCG instillation. Although this treatment is well tolerated in more than 95% of patients and its systemic complications can be effectively treated, these side effects can be life-threatening.