Chronic Reactive Arthritis Following Bacillus Calmette-Guérin (BCG) Instillations: A Case Report and Review

Background: Reactive arthritis (ReA) is an inflammatory joint condition that typically develops days to weeks after a gastrointestinal or genitourinary infection. While it is often associated with a classic triad of arthritis, urethritis, and conjunctivitis, many patients may not exhibit all three symptoms. Previously known as “Reiter syndrome,” named after Hans Reiter, ReA is thought to result from an abnormal autoimmune response to infections caused by pathogens such as Salmonella, Shigella, Campylobacter, or Chlamydia. Recognizing this connection is essential for effective diagnosis and treatment. Case Description: A 67-year-old male developed reactive arthritis (ReA) following intravesical Bacillus Calmette-Guérin (iBCG) therapy for non-muscle invasive bladder cancer. Elevated inflammatory markers and a negative HLA-B27 result were noted. The symptoms were attributed to iBCG-related ReA, leading to the discontinuation of iBCG treatment. Outcome: Initial treatment with nonsteroidal anti-inflammatory drugs (NSAIDs) and glucocorticoids was ineffective, necessitating disease-modifying antirheumatic drugs (DMARDs) for sustained remission and symptom control. Although chronic arthritis requiring prolonged DMARD therapy is uncommon, the patient required over 1.5 years of DMARD treatment to manage symptoms effectively.