What is Reactive Arthritis?
Reactive arthritis is joint inflammation triggered by an infection elsewhere in the body — usually in the gut or the urinary tract — appearing one to four weeks afterwards. The joints themselves are not infected. It typically affects a few large joints in the legs, and in most people it settles within six months.
Also called: Reiter's syndrome
Who gets Reactive Arthritis?
Most often young adults between 20 and 40. It follows gastrointestinal infection with Salmonella, Shigella, Campylobacter or Yersinia, or genitourinary infection with Chlamydia. People carrying the HLA-B27 gene are more likely to develop it, to have more severe disease, and to have a course that persists rather than settling.
What are the symptoms of Reactive Arthritis?
Not everyone has every symptom below, and having one does not confirm the diagnosis. These are the features that most often lead to assessment:
- Pain and swelling in a few large joints, typically knees, ankles and feet, usually asymmetrical
- Heel pain from inflammation where the Achilles tendon or plantar fascia attaches
- Swelling of a whole finger or toe
- Lower back and buttock pain
- Red, painful or gritty eyes from conjunctivitis or uveitis
- Burning on passing urine, or discharge, even without an active infection
- Skin changes on the palms and soles, or in the mouth
- Fever and fatigue at the onset
How is Reactive Arthritis diagnosed?
The diagnosis is made on the pattern of joints combined with a preceding infection — which the patient may not connect to the joints, and sometimes did not notice at all. A careful history of gut or urinary symptoms in the preceding month is essential.
Stool and urine testing, and testing for Chlamydia, may identify the trigger. Inflammatory markers are raised. HLA-B27 is often positive and is useful for prognosis rather than diagnosis.
Joint fluid is examined to exclude septic arthritis and gout, which can present identically. In reactive arthritis the fluid is inflammatory but sterile.
How is Reactive Arthritis treated?
Non-steroidal anti-inflammatories are the mainstay and are effective for most patients. Corticosteroid injection into a persistently swollen joint works well when only one or two joints are involved.
If a Chlamydia infection is still present it is treated with antibiotics, and sexual partners are treated too — but antibiotics do not shorten the arthritis once it has started, and they have no role in post-gastrointestinal cases.
Disease that persists beyond three to six months is treated with sulfasalazine or methotrexate, and a small proportion of patients with ongoing disease need a TNF inhibitor.
Any eye involvement needs same-week ophthalmology assessment.
Living with Reactive Arthritis
Between two-thirds and three-quarters of patients recover fully within three to twelve months. A minority develop chronic disease, and this is more likely in those who are HLA-B27 positive. Recurrence after a further infection is possible.
When should you see a rheumatologist?
Joint swelling appearing within a month of a gut or urinary infection, particularly with heel pain or eye redness, should be assessed promptly — mainly to exclude joint infection, which needs urgent treatment.
Common questions about Reactive Arthritis
How long does reactive arthritis last?
Most people recover within three to twelve months. A minority, particularly those who are HLA-B27 positive, develop persistent arthritis that needs longer-term treatment.
Is reactive arthritis contagious?
No. The arthritis itself cannot be passed on. The infection that triggered it may have been contagious, which is why sexual partners are treated when Chlamydia is identified.
Will antibiotics cure my reactive arthritis?
Antibiotics treat an ongoing infection if one is still present, but they do not shorten the arthritis once it has begun, and they have no role at all after a gastrointestinal trigger.
I never had an infection — can it still be reactive arthritis?
Yes. The triggering infection is often mild enough to be forgotten, and gut infections in particular can pass with little more than a day of loose stools.
This page is general information to support a consultation. It is not a diagnosis, and it does not replace an assessment by a doctor who has examined you.