What is Reactive Arthritis?
Reactive arthritis (ReA) is a type of joint inflammation that develops a few days to weeks after a stomach or urinary tract infection. It is commonly associated with three symptoms – joint inflammation (arthritis), inflammation of the urethra (urethritis), and eye inflammation (conjunctivitis). However, most patients may not show all three symptoms.
Previously, it was termed as “Reiter syndrome” in honor of Hans Reiter, the person who first identified the syndrome. But, this name is no longer used due to Reiter’s connection with the Nazi party and involvement in inhumane experiments on war prisoners carried out in the Kaiser Wilhelm Institute of Experimental Therapy.
Nowadays, it is suspected that this condition arises because of an abnormal immune response to a stomach infection caused by bacteria such as salmonella, shigella, campylobacter, or chlamydia.
What Causes Reactive Arthritis?
Reactive arthritis is a condition often caused by bacterial infection, particularly of the urinary tract (due to bacteria like Chlamydia trachomatis, Neisseria gonorrhea, Mycoplasma hominis, and Ureaplasma urealyticum) or the gastrointestinal tract (infections from bacteria like Salmonella enteritidis, Shigella flexneri, Yersinia enterocolitica, Campylobacter jejuni, Clostridium difficile).
Around 2% to 4% of people suffering from a genital infection, especially with Chlamydia trachomatis, may develop reactive arthritis. On the other hand, 0% to 15% might experience it after a gastrointestinal infection with bacteria like Salmonella, Shigella, Campylobacter, or Yersinia. However, the actual incidence of arthritis can vary depending on several factors such as where a person is located, environmental influences, how harmful the bacteria are, and the nature of the study being conducted.
This form of arthritis is often seen after intestinal infections. That said, reactive arthritis linked to Chlamydia is quite common, especially in developed countries.
There have also been a few reported cases of reactive arthritis occurring after the Bacillus Calmette Guerin (BCG) vaccine, usually used for treating bladder cancer.
Risk Factors and Frequency for Reactive Arthritis
Reactive arthritis is not very common, with about 0.6 to 27 out of every 100,000 people experiencing it. This condition tends to occur more frequently in adult males who are in their 20s and 30s. It’s also interesting to know that 1 to 3% of people with nonspecific urethritis, a type of urinary infection, can develop Reactive arthritis. Additionally, it has been observed that people from lower socioeconomic groups tend to have more severe disease symptoms and a worse ability to perform everyday tasks.
Signs and Symptoms of Reactive Arthritis
Reactive Arthritis (ReA) commonly presents several days to weeks after an initial infection. Initially, the patient may experience diarrhea or other issues that resolve by the time the joint inflammation, or arthritis, develops. The progression of ReA can vary, and while it may resolve by itself, it can also be recurrent or continuous. In some cases, around 20% to 25% of patients, it may even advance to cause chronic complications affecting the joints, eyes, and heart.
When ReA is sexually acquired, the affected person usually has a history of recent sexual intercourse, potentially with a new partner, within 3 months of the onset of joint symptoms. The genital symptoms, which can include painful urination, discharge or pain in men, or irregular menstruation, deep pelvic pain or unusual vaginal discharge in women, typically precede arthritis by approximately two weeks. Reactive Arthritis is also common in individuals with HIV, potentially causing severe skin conditions, especially on the scalp, soles, palms, and flexures.
- Discomfort in finger, toe, or heel
- Asymmetric oligoarthritis mostly in lower limbs
- Conjunctivitis or iritis
- Diarrhea or cervicitis within 4 weeks of starting arthritis
- Urethritis or genital ulcers
Two or more of these symptoms, combined with involvement of the skeletal system, usually lead to a Reactive Arthritis diagnosis. Patients often present with sudden intermittent arthritis, which mainly affects the lower extremities, sacroiliac joint, and lumbar spine. The joints often affected include the knee and ankle, and these are frequently warm, painful and swollen. Tendinitis is also a common feature.
There could also be extra-articular manifestations which affect parts of the body other than the joints. These might involve the skeletal system, eyes, genitourinary tract, mucosal and skin, heart, and even cause changes in nails. Skin changes are common and may include thickening and red, inflamed skin. Nail issues are also common. Eye problems, such as conjunctivitis and uveitis, are also common and require immediate attention to prevent visual loss. Very rarely, the heart can be involved causing electrical disturbances in early stages of the disease and valve dysfunction at more advanced stages. Spinal cord dysfunction and persistent gastrointestinal issues like diarrhea and colitis can also occur.
Testing for Reactive Arthritis
Reactive Arthritis falls under a category of joint disorders that trouble the main part of the skeleton. Arthritis is often asymmetric and impacts a few, typically not matching, joints. Other conditions in this category include Ankylosing Spondylitis and Psoriatic Arthritis.
In 1999, the American College of Rheumatology came up with guidelines to help diagnose Reactive Arthritis. They divided symptoms into two categories. The major symptoms include uneven joint swelling often in the lower body, and either signs of intestine inflammation (enteritis) or urinary tract inflammation (urethritis) within 3 days to 6 weeks before arthritis symptoms. Minor symptoms involve evidence of an infection that triggered the arthritis and chronic swelling of the joint membrane (synovitis).
If a patient has genital or urinary symptoms, joint pain in the foot and hand area, an overactive immune response (shown by increased C reactive protein), and the presence of a specific gene (HLA-B27), it gives a 69% chance of accurately diagnosing Reactive Arthritis with a 93.5% certainty that the patient doesn’t have a different condition.
Reactive Arthritis is generally diagnosed based on symptoms, however, labs also play a role to confirm recent or current infection. Lab tests detect certain bacteria that may have caused the infection and therefore, the reactionary arthritis. These bacteria include Chlamydia trachomatis, Neisseria gonorrhea, and Mycoplasma genitalium. Detection of these bacteria involves a type of lab analysis performed on urine samples or genital swabs.
Meanwhile, finding bacteria in the joint is strongly indicative of Reactive Arthritis but detection techniques available for urine samples may not work as well on joint samples. It’s also important to note that some lab tests for certain bacteria are of limited value due to issues like cross-reactivity (false positives) and inability to pinpoint the timing of infection.
Complications like uveitis, a type of eye inflammation, are important to identify. Uveitis can cause symptoms like acute pain, light sensitivity, visual impairment, red eye, and pus in the eye. If patients have these symptoms, they need immediate referral to an eye specialist.
Tests for inflammation markers like Erythrocyte Sedimentation Rate (ESR) and C-Reactive Protein (CRP), as well as a joint fluid test can help rule out other types of arthritis. There’s also a specific gene (HLA B 27) whose presence has been found to suggest a potentially harsher course of disease but it does not confirm the diagnosis.
Additionally, tests for tuberculosis may be needed for patients from areas where the disease is common.
Imaging tests like X-rays, ultrasounds, or MRIs can be used to spot joint inflammation, enthesitis (where tendons attach to the bone), or sacroiliitis (lower back inflammation). This may be helpful especially in the early stages of disease.
Treatment Options for Reactive Arthritis
If doctors find an infection that may have caused reactive arthritis, they’ll likely recommend antibiotic treatment, which can last anywhere from 3 to 6 months. This treatment can often speed up the recovery process. It’s also important to begin treatment quickly if you have an infection. However, if there isn’t an active infection present, antibiotics won’t help.
A study showed promising results with patients who tested positive for a bacteria called Chlamydia. These patients were treated for 6 months with different combinations of antibiotics: one group with doxycycline and rifampin, and another with azithromycin and rifampin. The results showed significant improvement of symptoms and reduction of the bacteria, although more research is needed to determine the best combination of antibiotics.
The main aim of reactive arthritis treatment is to alleviate symptoms and prevent long-term complications. Non-steroidal anti-inflammatory drugs, also known as NSAIDs, are usually the first choice for treatment in the early stages of the disease. If the arthritis is only affecting a few joints, localized treatments with glucocorticoids – a type of anti-inflammatory medication – may be used. In cases of more widespread joint inflammation, eye or heart problems, systemic glucocorticoids, which work throughout the body, may be used.
Devices like orthotics and insoles can also provide some relief. Disease-modifying antirheumatic drugs (DMARDs), primarily sulphasalazine, can be effective in treating both acute and chronic reactive arthritis. Other options, like methotrexate and azathioprine, have been shown to be helpful in chronic arthritis. These medications are typically considered when NSAIDs aren’t enough to manage the disease.
There’s also some evidence that biological agents, such as tumor necrosis factor (TNF) blockers, may be beneficial in treating reactive arthritis. However, more research is needed to confirm their effectiveness.
All patients are encouraged to maintain physical activity to prevent muscle loss. Strength exercises play a key role in long-term treatment.
What else can Reactive Arthritis be?
When a doctor encounters symptoms similar to a certain condition, they need to consider and rule out other possible diseases that could cause the same symptoms. The most common possibilities they might consider are:
- Gonococcal arthritis (a type of bacteria-caused arthritis)
- Gouty arthritis (arthritis caused by excess uric acid)
- Still disease (a serious disorder that can cause high fevers and inflammation)
- Septic arthritis (joint infection)
- Rheumatic fever (a disease that can result from untreated strep throat)
- Psoriatic arthritis (a type of arthritis affecting some people with psoriasis)
- Ankylosing spondylitis (a type of spinal inflammation)
- Rheumatoid arthritis (an autoimmune disease causing joint inflammation)
- Arthritis related to immunotherapy or immunization
- Secondary syphilis (the second stage of a bacterial infection)
- Tubercular arthritis (joint condition caused by tuberculosis)
What to expect with Reactive Arthritis
Reactive arthritis is typically a temporary condition and its symptoms usually go away within 3 to 5 months. If symptoms persist beyond 6 months, it’s often a sign of a long-term element of the disease. Sacroiliitis, a type of joint disease affecting the lower back, is the most common long-term issue.
People who have a gene marker known as HLA-B27 are at a higher risk of experiencing reactive arthritis again. About 15-30% of people with this condition may develop long-term arthritis or other joint abnormalities. Factors that might indicate a worse outcome include hip involvement, if the condition does not respond to non-steroidal anti-inflammatory drugs (NSAIDs), and if a blood test shows an erythrocyte sedimentation rate (ESR) – which measures inflammation in the body – is higher than 30.
Possible Complications When Diagnosed with Reactive Arthritis
Possible complications of ReA, or Reactive Arthritis, may include:
- Arthritis that keeps coming back, observed in 15%-50% of cases
- Persistent arthritis or inflammation of the lower back joints
- Stiffening of the spine, more common in patients who tested positive for HLA-B27(around 30%-50% of such cases)
- Narrowing of the urinary tube
- Decay or destruction of the base of the aorta, the body’s main blood vessel
- Clouding of the eye lens known as cataracts
- Swelling in a part of the retina responsible for sharp, central vision (Cystoid macular edema)
Preventing Reactive Arthritis
Often, it can be difficult for patients to openly discuss symptoms related to their urinary and reproductive systems due to societal stigma. This can make it challenging for doctors to get a full and accurate understanding of the patient’s condition. Some research suggests that treating a sudden infection in these systems with three months of antibiotics could stop reactive arthritis from developing, although this idea is debated among medical professionals.
From a doctor’s viewpoint, quickly recognizing the combination of sight-related, urinary/reproductive system, and joint pain symptoms as related can be an against-the-clock task. This is especially true if the patient develops sudden inflammation of the uvea or iris (parts of the eye), a condition known as acute uveitis or iritis. These conditions can quickly lead to permanent vision loss if not treated promptly.