Reactive arthritis: images.

Reactive arthritis is an extremely rare spondyloarthritis that affects the peripheral joints and spine, resulting in common symptoms such as arthritis, urethritis, conjunctivitis, and mucocutaneous lesions. On rare occasions, oral lesions such as circinate erosions on the hard and soft palate, gums, tongue, and cheeks may occur. Reactive arthritis may develop during or after genitourinary or gastrointestinal bacterial infections such as Shigella, Salmonella, Yersinia, and Chlamydia.