[Polyarthritis in 4 patients treated with intravesical BCG-therapy for carcinoma of the bladder].

Intravesical administration of Calmette-Guérin bacillus (BCG) is effective in the treatment of superficial bladder carcinoma. Transient arthritis or migratory arthralgia has been reported in 0.5% of cases. The authors report on four men (mean age 65 years), who developed an oligoarthritis in three cases after the 2nd, 5th, and 6th weekly instillation of Pasteur BCG, respectively, and symmetrical polyarthritis in one after 48 BCG instillations over a three-year period. Joints involved were the knees (3/4), ankles (3/4), shoulders (1/4), wrists, and hands (1/4). Features included morning stiffness and local evidence of inflammation. All four patients had an elevated erythrocyte sedimentation rate and negative tests for rheumatoid factor. Neutrophils were the main cell type in synovial fluid. Synovial biopsy performed in two cases revealed non-specific inflammation. Erosions of the metatarsophalangeal joints were observed in one patient. Locoregional or systemic symptoms included transient fever (3/4), cystitis (4/4), urethritis (1/4), epididymoorchitis (2/4), conjunctivitis (1/4), and pleural effusion with pericarditis (1/4). The BCG was recovered from an epididymal specimen in one patient. Two patients were positive for the HLA B27 antigen. Outcome was favorable in every case (range: 15 days-6 months) after discontinuation of BCG therapy and administration of isoniazid, rifampin, and prednisone (3 patients) or NSAID (1 patient). Various pathogenic hypotheses for BCG-induced arthritis are discussed, including infection, immune responses to heat shock proteins, and reactive arthritis.