Dr. Abhrajit Ray

Reactive arthritis is a painful form of inflammatory arthritis (joint disease due to inflammation). It occurs in reaction to an infection by certain bacteria. Most often, these bacteria are in the genitals (Chlamydia trachomatis) or the bowel (Campylobacter, Salmonella, Shigella and Yersinia). Chlamydia most often transmits by sex. It often has no symptoms, but can cause a pus-like or watery discharge from the genitals. The bowel bacteria can cause diarrhea. If you develop arthritis within one month of diarrhea or a genital infection - especially with a discharge - see a health care provider. You may have reactive arthritis.

What causes Reactive Arthritis?

The bacteria induce (cause) arthritis by distorting your body's defense against infections, as well as your genetic environment. How exactly each of these factors plays a role in the disease likely varies from patient to patient. This is a focus of research.
1) Reactive arthritis can have any or all of these features:
2) Pain and swelling of certain joints, often the knees and/or ankles
3) Swelling and pain at the heels
4) Extensive swelling of the toes or fingers
5) Persistent low back pain, which tends to be worse at night or in the morning
Some patients with this type of arthritis also have eye redness and irritation. Still other signs and symptoms include burning with urination and a rash on the palms or the soles of the feet.

How is Reactive Arthritis diagnosed?

Rheumatologists are experts in diagnosing arthritis and other rheumatic diseases. Other doctors may feel less comfortable diagnosing reactive arthritis. This is because diagnosis is based on clinical features and not on tests.
Diagnosis is largely based on symptoms of the inducing infections and appearance of typical musculoskeletal (joint and muscle) involvement. If indicated, doctors might order a test for Chlamydia infection or test for the HLA-B27 gene. The test for Chlamydia uses a urine sample or a swab of the genitals.