Bacillus Calmette-Guérin-induced perinuclear antineutrophil cytoplasmic antibodies associated vasculitis in bladder cancer.

Intravesical instillation of Bacillus Calmette-Guérin (BCG) immunotherapy remains the most effective adjuvant treatment for noninvasive bladder cancer. Systemic BCG-related complications are rare and usually related to infective agent or an immune-mediated reaction. We discussed a case with perinuclear antineutrophil cytoplasmic antibodies (p-ANCA) vasculitis, developing after instillation of BCG for non-invasive bladder cancer. A 68-year-old man presented with nephritic syndrome a few months after BCG instillations which was performed for his non-muscle-invasive bladder cancer adjuvant therapy. The renal function had declined slowly after the first instillation and urinary sediment reveals the new onset of nephritic proteinuria and hematuria. High titer of p-ANCA was present. His renal biopsy was consistent with acute renal vasculitis. The patient's creatinine level regressed with immunosuppressive therapy and he was clinically followed up without hemodialysis. Here, we presented a patient that diagnosed as p-ANCA related vasculitis occurred after BCG instillation.