Reactive arthritis

What is reactive arthritis?

Reactive arthritis is an uncommon disease that causes inflammation of the joints and, in many cases, other areas, particularly the urinary tract and eyes. It is triggered by an infection, usually by a sexually transmitted organism or by certain gastrointestinal bacteria.

The most common infection causing reactive arthritis is the sexually transmitted disease (STD) chlamydia. Reactive arthritis can also be caused by gastrointestinal infection from bacteria such as Salmonella, Shigella, Campylobacter or Yersinia, infections that can cause diarrhea and vomiting. These bacteria often are found in contaminated food or water. While these infections are common, reactive arthritis is not. One theory about why some people seem to be more prone to develop reactive arthritis is that they have a certain genetic makeup. Supporting this theory is the observation that up to 60% of people with reactive arthritis carry a gene called HLA-B27, compared with 8% of the general population.

Another theory suggests that the gut microbiome (the micro-organisms living within the intestinal tract) plays an important role in the development of reactive arthritis. The idea is that a reduction in beneficial bacteria, an increase in harmful bacteria, and/or less diversity of micro-organisms alters immune function, which leads to reactive arthritis.

Whether due to genetic factors, features of the microbiome, or some other mechanism, reactive arthritis is thought to be an autoimmune disorder in which the immune system is jolted into action by the infection but continues attacking various parts of the body even if the infection is gone.

Reactive arthritis typically includes arthritis, eye inflammation (conjunctivitis or uveitis), and inflammation of the urethra (urethritis). However, some people develop only one or two of these. Reactive arthritis is most common in people between the ages of 20 and 40, with estimates of prevalence ranging from one in 1,000 to one in 10,000.

Symptoms of reactive arthritis

Symptoms usually appear within a few weeks after someone has had chlamydia or a diarrheal infection. Most people feel a little tired and have a slight fever, although a few have high fever, significant fatigue, and weight loss. Other early symptoms include muscle aches, joint stiffness, and low back pain radiating into the buttocks or thighs. Back discomfort is usually worse in the morning, gets worse when you sit or lie still, and gets better when you move around. Arthritis begins abruptly and usually affects one or several joints, especially the knees, ankles, feet, or wrists. People often have pain at the back of an ankle or tenderness on the bottom of a heel (from inflammation at the spot where a tendon attaches to a bone).

Symptoms vary depending on what other areas of the body are inflamed:

• arthritis: joint pain; swelling; limited motion, especially of the ankles, knees, feet, and less commonly of the wrists, fingers or other joints; tendon pain; low back pain; swelling in a finger or toe
• conjunctivitis: redness near an eyelid with sticky discharge from the eye, especially in the morning (usually mild and temporary)
• uveitis: redness near the iris of the eye, pain (especially when exposed to light), blurred vision
• urethritis: painful urination, a discharge from the penis or vagina
• dermatitis: painless or painful sores in the mouth, a scaly rash on the soles of the feet, inflammation at the tip of the penis.

Other symptoms are rarer, including inflammation of the prostate (prostatitis), bladder (cystitis), or heart lining (pericarditis), and leaking of the aortic valve.

Diagnosing reactive arthritis

A doctor may suspect you have reactive arthritis when the typical symptoms develop after you have an infection. Your doctor will examine you and may order imaging tests, such as x-rays of the pelvis or lower spine. Your doctor may remove fluid from a painful joint with a needle so it can be examined in a laboratory. Fluid from an inflamed joint will contain a high number of white blood cells but there is no detectable infection in the joint.

There is no single test that can confirm the diagnosis. Your doctor will diagnose reactive arthritis based on a combination of information from your history of infection, symptoms, and physical exam. Tests may be performed to check for other conditions that can cause joint inflammation, such as an infection or gout.

Expected duration of reactive arthritis

For reasons that are not yet known, reactive arthritis sometimes gets better on its own over a number of months or years. However, it is often chronic (long-lasting), and treatment may be needed long-term, even for a lifetime.

Preventing reactive arthritis

Reactive arthritis can be prevented by preventing the infections that trigger it. And the risk of reactive arthritis can be reduced by treating these infections promptly when they arise.

You can help to prevent gastrointestinal infections by properly cooking food and washing your hands thoroughly after contact with animals and before preparing food. You can reduce the risk of STDs by practicing safer sex or abstaining from sex.

Treating reactive arthritis

The choice of treatment for reactive arthritis depends on your specific symptoms. If you still have the infection, your doctor will prescribe antibiotics, usually for seven days. Though some physicians treat chlamydia infections with antibiotics for several months, there is a lack of convincing evidence that this longer treatment helps to prevent reactive arthritis. The sexual partners of a person with newly diagnosed chlamydia should also be treated.

For mild arthritis, a nonsteroidal anti-inflammatory drug (NSAID) with or without a pain reliever, such as acetaminophen (Tylenol and other brand names), may be enough. For more severe arthritis, injections of corticosteroids into the inflamed joint can relieve pain, although the relief is often temporary.

Other medications that may be helpful include those used to treat rheumatoid arthritis, such as corticosteroids, sulfasalazine, hydroxychloroquine, or methotrexate (all available as generics). Injectable medications used to treat rheumatoid arthritis may also be used, including adalimumab (Humira), certolizumab (Cimzia), etanercept (Enbrel), golimumab (Simponi), or infliximab (Remicade). For persistent arthritis despite other treatments, secukinumab (Cosentyx), ixekizumab (Taltz), tofacitinib (Xeljanz), and upadacitinib (Rinvoq) may be effective.

Surgery to replace a joint may help severe arthritis that does not respond to medications.

It's important to balance rest and exercise. Biking and swimming, for example, can help to reduce stiffness and keep the joint moving. Your doctor may refer you to a physical therapist, occupational therapist, or podiatrist. Splints, shoe inserts, or braces can provide relief in ways that medications cannot.

For the other manifestations of disease, treatment options include

• corticosteroid cream or ointment for rash; supervision by a dermatologist is important, especially if the rash involves the penis or face
• corticosteroid eye drops, injections, or pills for uveitis
• NSAIDs or other pain relievers for urinary tract inflammation (urethritis).

The care of people with reactive arthritis should be coordinated by their primary care physician with regular monitoring by appropriate specialists, which may include a dermatologist, ophthalmologist, rheumatologist, or urologist.

When to call a professional

Call your doctor if you have symptoms of reactive arthritis such as joint pain, swelling, limited motion, red or painful eyes, or painful urination. If you notice pain or burning with urination, or a discharge from the penis or vagina, call your doctor right away. Let your doctor know if you have diarrhea that is persistent, bloody, or associated with pain.

Prognosis

With therapy, the outlook for reactive arthritis is good, although the condition is quite variable. Severe cases may be associated with significant joint damage, vision problems, and other disabling manifestations, whereas other cases are much milder and only intermittently bothersome. Risk factors for more severe disease include one or more of the following:

• male gender
• venereal infection (rather than intestinal infection)
• sacroiliac or hip joint involvement
• swelling of a finger or toe
• blood tests showing evidence of marked bodywide inflammation
• presence of gene marker, HLA-B27
• poor response to initial therapy.

Additional info

American College of Rheumatology
https://www.rheumatology.org/

Arthritis Foundation
https://www.arthritis.org/

Spondylitis Association of America
https://www.spondylitis.org