Mr. Arthur Itis is a previously healthy 30-year-old gentleman. In early August, he had a bout of food poisoning from the bacteria Salmonella. Three weeks later he noticed his right heel was painful and swollen, and he had low back pain and stiffness upon arising in the morning. Later that week, his right knee and ankle and several of his fingers and toes became painful and swollen. What could this be?
Mr. Arthur Itis has reactive arthritis. Reactive arthritis occurs when an infection, such as Salmonella, alters a person’s immune system, leading to autoimmune disease. The immune system is comprised of blood cells and tissues within our bodies that usually serve to fight off bacteria and viruses. Autoimmune disease occurs when a person’s immune system has become dysfunctional and attacks healthy body parts. In reactive arthritis, the altered immune system incorrectly attacks healthy joints and tendons (the fibrous connection between the muscle and bone) leading to pain and swelling.
Reactive arthritis is not to be confused with septic arthritis, which is when a bacterium has infected a person’s joints. That is to say that Mr. Arthur Itis doesn’t have Salmonella in his joints causing the pain and swelling, but, rather, the Salmonella infection from weeks ago triggered his immune system to mistakenly attack his joints.
Different types of infections can trigger a reactive arthritis but the most common infections are genitourinary infections (Chlamydia) or bowel infections (Campylobacter, Salmonella, Shigella and Yersinia). Joint pain and swelling typically occur 1-4 weeks after the infection.
Reactive arthritis occurs most commonly in people between ages 20 and 50. People who carry a gene called HLA B 27 are more likely to get reactive arthritis, but reactive arthritis can happen in those without the gene as well.
The most common sites affected by reactive arthritis are the heels, toes, fingers, low back, knees and ankles. A rash on the palms and soles or genitals, painful urination, or eye inflammation also can occur in some cases.
Anti-inflammatory medications such as Naproxen or Ibuprofen are considered firstline medications. Most people with reactive arthritis have little to no disease activity after 6-12 months, but 15 to 20 percent may experience persistent arthritis. Steroid medications and immunosuppressant medications may be required in these cases.