Miliary Pulmonary Tuberculosis After Intravesical BCG Instillation in a Patient with High-Grade Bladder Cancer

Intravesical administration of Bacillus Calmette-Guerin (BCG) vaccine is used in the treatment of superficial bladder cancer. In clinical practice, intravesical BCG immunotherapy after transurethral tumor resection is a highly effective treatment option in preventing tumor recurrence and progression in medium and high risk superficial bladder tumors. Since patients are given live tuberculosis (TB) bacillus, serious side effects such as pneumonia, sepsis and even death can be seen. Lung involvement occurs in less than 1% of patients and most commonly presents as interstitial pneumonia or miliary TB. Miliary TB is difficult to diagnose and is usually based on high clinical suspicion, as Mycobacterium bovis is not isolated in most cases. Treatment is not completely standardized. However, in severe cases, a combination of anti-tuberculosis drugs and corticosteroids is recommended. In this report, a case of miliary tuberculosis, a very rare complication after instillation of BCG into the bladder in a patient with a diagnosis of superficial bladder cancer, was presented. A 73-year-old male patient diagnosed with bladder tumor underwent transurethral resection of bladder tumor, and then weekly intravesical injection of BCG-MEDAC for six weeks had no adverse effects. Three weeks of intravesical BCG supplementation was planned for the patient who had no signs of recurrence when checked three months later by cystoscopy. Two hours after the first dose, the patient, who applied to the emergency department with the complaint of chills and shivering, was hospitalized for further follow-up and treatment. Afterwards, repeat cultures were taken from the patient whose fever continued on the seventh day of treatment with broad-spectrum antibiotics (meropenem and teicoplanin). In addition, when abdominal and thorax computed tomography (CT) were performed, multiple miliary nodular lesions were detected in both lungs and were evaluated in favor of miliary TB. With these findings, the patient was started on miliary TB therapy [isoniazid (INH), rifampicin (RIF), ethambutol (EMB) and streptomycin (STM)] targeting Mycobacterium bovis, since it was an infection that developed after BCG injection. In the third week of the treatment, the patient's fever was under control, and he was discharged on the 25th day of his hospitalization because of significant improvement in infection markers [C-reactive protein(CRP)-procalcitonin]. At the end of two months, there was clear regression of pulmonary abnormalities on control thorax CT. In conclusion, miliary TB developing after intravesical BCG instillation is a very rare condition, the cause of which is not fully understood, the etiology of fever can be easily missed, and the diagnosis is difficult. In addition, this case is presented to draw attention to a critical disease that requires long treatment and follow-up and requires attention.