A rare cause of reactive arthritis etiology: bacillus calmette-guerin immunotherapy

Reactive arthritis belongs to the spondyloarthritis group that manifests up to 6 weeks after a gastrointestinal or genitourinary infection. Usually presents with asymmetric monooligo arthritis on the lower extremity and accompanying extraarticular findings can often be observed on follow-up. Here in, we discussed a case of reactive arthritis developed after intravesical Bacillus Calmette Guerin immunotherapy used as adjuvant treatment for bladder cancer.