What is a common history finding for reactive arthritis?

• A. Recent dental infection
• B. Recent shingles
• C. No preceding illness
• D. Traveler's diarrhea

Answer: (D)

Reactive arthritis is an inflammatory joint condition that develops after an infection elsewhere in the body, most commonly a gastrointestinal or genitourinary infection. The history typically reveals a preceding illness with diarrhea or urethritis that occurred about one to a few weeks before the joint symptoms begin. Traveler’s diarrhea fits this pattern perfectly because it represents a GI infection acquired abroad, often due to pathogens like Campylobacter, Salmonella, Shigella, or Yersinia. After such an infection, the immune system can react and trigger arthritis, sometimes with additional features like eye involvement or skin/mucous membrane lesions.

Other options don’t fit this typical chain as well: a dental infection isn’t the classic trigger for reactive arthritis, shingles represents a dermatologic/viral reactivation rather than a distant GI/GU trigger, and having no preceding illness doesn’t align with the common post-infectious mechanism.