A case of renal granulomatosis with polyangiitis following intravesical bacillus Calmette-Guérin therapy

Various adverse reactions may occur after intravesical bacillus Calmette-Guerin (BCG) therapy. Although the virulence of attenuated BCG is low, serious complications such as bacterial cystitis, bladder contractures, granulomatous prostatitis, epididymitis, orchitis, and systemic reactions such as fever and malaise have been described. Disseminated granulomatosis such as hepatitis and pneumonitis have also been described, but are rare. We report here the case of a 67-year-old patient who presented with renal granulomatosis with polyangiitis following intravesical BCG therapy for superficial bladder tumor. The biological evaluation revealed the presence of perinuclear anti-neutrophil cytoplasmic antibodies with specificity for antimyeloperoxidase. Renal biopsy specimen revealed pauci-immune crescentic glomerulonephritis with segmental glomerular necrosis, presence of granulomas and no evidence of any caseating necrosis. He received antituberculosis drugs in addition to corticosteroids and cyclophosphamide without any improvement of the renal function.