Ruptured Mycotic Aneurysm After Intravesical Instillation for Bladder Tumor

Intravesical instillation of Bacillus Calmette-Guérin (BCG) is an effective and widely used treatment for patients with in situ bladder cancer. Major complications are quite uncommon, but a systemic dissemination of the attenuated strain of Mycobacterium bovis is possible. Few cases of aortic rupture caused by M bovis infection are described in literature.

A 70-year-old male, treated 3 months before with BCG instillation, presented to the emergency department because of a ruptured abdominal aortic aneurysm. The patient was hemodynamically stable, with a "hostile" abdomen. Therefore, an Endologix AFX endograft was deployed. During the postoperative period, his blood inflammatory markers increased, suspicious of a graft infection. Single-photon emission computed tomography (CT)/CT scan showed aortic increased uptake. Antibiotic therapy was continued, but after some days, the patient presented with hematemesis, and the CT scan showed an aortoenteric fistula. In emergency, the infected graft and aneurysm were removed, enteric fistula was closed, and an axillobifemoral bypass was performed. The patient died 25 days after endovascular aneurysm repair explantation.

Despite the high suspicion of mycotic aortic aneurysm and graft infection by M bovis, there is no proof of this theory because of the absence of any positive culture test. M bovis is a slow-growing bacteria, and specific culture tests are required to identify it; indeed, all our blood and intraoperative samples were positive to other bacteria, probably the contaminant ones.

Mycotic aneurysm is an extremely rare complication of intravesical BCG therapy, but it must be taken into consideration in patients with rapidly growing aortic aneurysms or rupture of a normal aorta, who have been previously submitted to this kind of instillation.