There is no single test to determine whether or not a person has reactive arthritis. Instead, doctors must gather information to rule out or hone in on the cause of a patient’s symptoms. Information may be gathered from a patient interview, physical exam, lab tests, and medical imaging. A definitive diagnosis may take several days or even months.
See Arthritis Treatment Specialists
Patient Interview and Physical Exam
During the office visit, patients should:
- Let their doctors know about recent prior or ongoing infections
- Describe their joint pain and other symptoms, as well as when symptoms started
A doctor will examine the patient, listening to the patient’s heart and checking for things such as swollen joints, swollen fingers and toes, tender spots, and skin and eye abnormalities.
If a sexually transmitted disease (STD) or infection of the urethra is suspected, the doctor may also look at the patient’s genitals to note any rashes, sores, or abnormal discharge. The doctor may swab the area to run lab tests that check for infection.
Lab Tests
If a doctor suspects a patient has reactive arthritis, he or she will typically order lab tests.
Confirm infection. After an infection, the blood will contain certain antibodies. A doctor who suspects reactive arthritis may order a blood test to determine the presence of these antibodies; however, these tests may take several days and are not always accurate or easy interpret.
Inflammatory markers. When a person has an inflammatory condition like reactive arthritis, signs of inflammation are present in the blood. A blood sample may be taken to test for inflammatory markers such as:
- CRP. When there is inflammation in the body, the liver produces a protein called C-Reactive Protein (CRP).
- Erythrocyte sedimentation rate (ESR). The faster red blood cells (erythrocytes) fall to the bottom of a tube filled with the patient’s blood, the greater the degree of inflammation.
An abnormally high CRP level and ESR support the notion that symptoms are caused by reactive arthritis or another inflammatory condition. (One exception: people who have reactive arthritis due to chlamydia may not have notably high inflammatory markers.)
See Inflammatory Arthritis
HLA-B27. People with a gene called HLA-B27 are more likely to develop reactive arthritis. Experts estimate only about 8% of people around the world have this gene 1 Ajene AN, Walker CLF, Black RE. Enteric Pathogens and Reactive Arthritis: A Systematic Review of Campylobacter, Salmonella and Shigella-associated Reactive Arthritis. Journal of Health, Population, and Nutrition. 2013;31(3):299-307., but they account for 50% to 96% of reactive arthritis cases. 2 Schmitt SK. Reactive Arthritis. Infect Dis Clin North Am. 2017;31(2):265-277., 3 Sieper J. Pathogenesis of reactive arthritis. Curr Rheumatol Rep 2001;3(5):412–8., 4 Altman, R. Reactive Arthritis. Merck Manual Professional Edition Last reviewed November 2011. Accessed April 13, 2017. Testing for this gene can be done with a blood sample.
Joint fluid. Most joints contain a small amount of fluid, called joint fluid or synovial fluid. This fluid can be extracted using a needle and syringe and then tested for signs of an infection or a crystal arthritis, such as gout. This procedure is called joint aspiration.
See What Is Arthrocentesis (Joint Aspiration)?
A doctor may order none, some, or all of these lab tests depending on the patient’s symptoms, costs, and other circ*mstances.
Medical Imaging
Doctors may recommend an x-ray or MRI of the painful joint. An x-ray may suggest joint swelling or other irregularities. An MRI can provide much more detailed images, but it takes longer and is more expensive.
Doctors use the above diagnostic tools to rule out other conditions that can produce the same or similar symptoms. For example, a gonorrhea infection that has spread to the bloodstream, septic arthritis, and Lyme disease can also cause joints to feel painful and swollen. When patients with chronic diarrhea develop joint pain, doctors may consider inflammatory bowel disease as a possible diagnosis.
FAQs
HLA-B27. This blood test looks for the presence of HLA-B27, a genetic risk factor for reactive arthritis. Having this marker is consistent with having reactive arthritis, but it is not definitive—people who test negative can still have reactive arthritis, and not everyone who tests positive has the condition.
How bad is reactive arthritis? ›
Some people may have mild arthritis symptoms for up to a year. Others may develop mild, long-term arthritis. Up to half of people will have a flare-up of reactive arthritis in the future. In rare cases, the condition may lead to chronic, severe arthritis.
What genetic marker is linked to reactive arthritis? ›
People who have a gene called HLA-B27 have a higher risk of getting reactive arthritis and of experiencing more severe and more long-lasting symptoms. But people who lack HLA-B27 can still get the condition.
How rare is reactive arthritis? ›
Reactive arthritis is most common in people between the ages of 20 and 40, with a prevalence of about 0.03% (30 per 100,000).
What are the red flags for reactive arthritis? ›
Symptoms of reactive arthritis
pain, swelling or stiffness in a joint (arthritis) pain in the lower back and buttocks. pain and inflammation of tendons, such as the Achilles tendon at the back of the heel. pain and redness in the eyes.
What mimics reactive arthritis? ›
Conditions That Can Look Like RA
- Lyme Disease.
- Psoriatic Arthritis.
- Sjögren's Syndrome.
- Gout.
- Fibromyalgia.
- Lupus.
Arthritis causes more than just pain. It's a leading cause of disability. A disability is a condition that limits your typical movements, senses, or activities.
What is the best medication for reactive arthritis? ›
Prescription nonsteroidal anti-inflammatory drugs (NSAIDs), such as indomethacin (Indocin), can relieve the inflammation and pain of reactive arthritis. Steroids. A steroid injection into affected joints can reduce inflammation and allow you to return to your usual activity level.
What is the long-term prognosis for reactive arthritis? ›
Reactive arthritis causes inflammation (redness and swelling) in different parts of the body. It usually develops after an infection. In most cases it clears up in a few months without causing long-term problems.
What is the hallmark of reactive arthritis? ›
The hallmark features of reactive arthritis include urethritis, eye symptoms (conjunctivitis, iritis, uveitis), oral lesions, arthritis, and spinal involvement.
Reactive arthritis is a type of arthritis caused by an infection. It may be caused by Chlamydia trachomatis, salmonella, or another infection. The condition may cause arthritis symptoms, such as joint pain and inflammation. It may also cause symptoms in the urinary tract and eyes.
How long does it take for reactive arthritis to go away? ›
Inflammation also can affect the eyes, skin and the tube that carries urine out of the body (urethra). Previously, reactive arthritis was sometimes called Reiter's syndrome. Reactive arthritis isn't common. For most people, signs and symptoms come and go, eventually disappearing within 12 months.
Is reactive arthritis progressive? ›
ReA can be self-limiting, recurrent, or continuous, and about 20% to 25% of the patients may progress to have chronic articular, ocular, and cardiac complications. Reactive arthritis is very common in HIV individuals, and hence patients with the new-onset disease must have HIV ruled out.
Why do I keep getting reactive arthritis? ›
We don't yet know why some people get reactive arthritis, but we do know that it's linked to a gene that some people inherit, called HLA-B27. These people seem to be more likely to develop reactive arthritis and to get it more than once in their life.
How painful is reactive arthritis? ›
Reactive arthritis is a rare form of arthritis caused by bacterial infections. The infection usually affects your urinary tract, eyes, skin and joints. Reactive arthritis symptoms can include severe joint pain that affects your quality of life. It can take several months to recover from reactive arthritis.
Does arthritis show up in routine blood work? ›
No blood test can definitively prove or rule out a diagnosis of rheumatoid arthritis, but several tests can show indications of the condition. Some of the main blood tests used include: erythrocyte sedimentation rate (ESR) – which can help assess levels of inflammation in the body.
Are inflammatory markers raised in reactive arthritis? ›
An abnormally high CRP level and ESR support the notion that symptoms are caused by reactive arthritis or another inflammatory condition. (One exception: people who have reactive arthritis due to chlamydia may not have notably high inflammatory markers.)
What is the laboratory diagnosis of reactive arthritis? ›
Diagnosis of reactive arthritis may be difficult, because there are no specific laboratory tests that can confirm it. However, diagnosis may be confirmed based on a personal medical history and reported symptoms. Certain blood tests may be performed to rule out other conditions, such as rheumatoid arthritis and lupus.
Does inflammation always show up in blood tests? ›
Sometimes false negative results occur when inflammation actually is present. False positive results may occur when abnormal test results suggest inflammation even when none is present.
