Step 2 CK First Aid Rapid Practice Test

Arthritis that presents with conjunctivitis and urethritis in a young man is classic reactive arthritis. This is a sterile inflammatory arthritis that occurs after an infection elsewhere in the body, most commonly enteric bacteria or sexually transmitted organisms. The organisms tied to this syndrome include Campylobacter, Shigella, Salmonella, and the sexually transmitted Chlamydia trachomatis and Ureaplasma urealyticum. The joint pain is driven by an immune response to the prior infection rather than by joint infection itself, and the conjunctivitis and urethritis reflect the same post-infectious inflammatory process.

This pattern helps differentiate it from septic arthritis, which is a true joint infection typically presenting with a single hot, swollen joint and systemic illness; and from gonococcal arthritis, which is a septic process due to Neisseria gonorrhoeae and doesn’t classically show the triad of arthritis with conjunctivitis and urethritis. Rheumatoid arthritis is an autoimmune condition with a different presentation and does not require a triggering infection.