Reactive arthritis is a reaction that occurs in your body, usually after you’ve had some sort of infection. It causes an arthritis-type response in your joints with symptoms of swelling, redness, and inflammation. Commonly it affects the joints of the lower legs including the knees and hips, but it can also affect any joint. In the majority of cases, there are no long-term complications, although it can take a few months to clear up properly.
The symptoms are more common in men but can affect both genders. Inflammation of the joints can lead to symptoms of pain, swelling, and stiffness. But in others, it can also affect the eyes and the genitals. The genitals can have discharge or pain when passing urine in both men and women. The eyes can become sticky with discharge, painful, red, and sometimes there can also be inflammation (iritis). If you get any eye symptoms at all, it needs to be assessed whether it is iritis that needs immediate treatment.
Reactive arthritis often occurs after a recent infection. The exact mechanism of action is unclear but the initial infection causes an immune response and in some people leads to an overreaction of the immune system. This overreaction can lead to other cells and tissues becoming inflamed soon after. Most commonly it is due to sexually transmitted infections like chlamydia, but it can also be caused by tummy infections like gastroenteritis or glandular fever. Some people have a specific gene called HLA-B27, and this puts them more at risk of developing reactive arthritis.
Reactive arthritis is a diagnosis of exclusion, which means there is no test that can identify it. Your doctor will ask you questions about symptoms, your medical and sexual history. Your doctor may need to rule out other causes or find evidence of recent infection and this can be through a number of investigations such as blood tests, urine samples, stool samples and STI swabs. Your doctor may request imaging such as ultrasound scans or X - rays. If your doctor thinks reactive arthritis may be the diagnosis they can refer you to specialist doctors, such as an eye doctor if you have problems with your eyes or an arthritis specialist if you have problems with your joints.
Reactive arthritis usually lasts from a few months up to a year. If your symptoms include pain, your doctor will recommend painkillers such as ibuprofen if which can help reduce inflammation, helping reduce pain and swelling. If you have a sexually transmitted infection your doctor will prescribe antibiotics to help clear the infection. If the joint pain and swelling (arthritis) are prolonged or severe, the arthritis specialists may suggest starting medication such as immune-modulating drugs such as steroids or stronger drugs called DMARDs (disease-modifying anti-rheumatic drugs).