Systematic Review of Case Reports of Bacillus Calmette-Guerin Vascular Infections

Background: Bacillus Calmette-Guerin (BCG) is a live attenuated strain of Mycobacterium bovis that has been used as immunotherapy against several malignancies. In particular, intravesical instillation of BCG has become a well-accepted adjuvant treatment for bladder cancer. BCG vascular infections are a rare complication of BCG therapy. Many aspects of these infections, including the presentations, risk factors, and treatment strategies, are poorly understood. Through a systematic review of the existing literature, we aimed to identify potential associations between this condition and patient characteristics, presentations, its treatments, and outcomes. Methods: We searched the PubMed, MEDLINE, and Embase databases for cases of BCG vascular infections from inception to June 2021. English-language reports of BCG vascular infections were included. Results: A total of 74 cases of BCG vascular infections were included. Seventy-three (99%) cases were male patients, all of whom were exposed to BCG through bladder instillation. Fifty (68%) cases were diagnosed more than 12 months after exposure to BCG. Twentysix (35%) cases presented with arterial rupture at the time of diagnosis. Concurrent BCG infections in nonvascular locations were present in 37 (50%) cases. The most common locations of BCG vascular infection were the abdominal aorta (57%), prosthetic grafts (15%), and thoracic aorta (12%). The most common treatment for BCG infection was open repair with synthetic graft in situ replacement for the abdominal aorta and endovascular repair for the thoracic aorta. The 30-day mortality, among the 59 cases where these data were reported, was 10%. Conclusions: We observed that many aspects of BCG vascular infections are similar to other forms of vascular infections. The high incidence of rupture or fistulation and the propensity toward abdominal aortic involvement and its prognosis are similar to those described in other vascular infections. However, our study also highlights 2 idiosyncratic features of BCG vascular infections: association with male sex and concurrent musculoskeletal infections.