Reactive arthritis overview
|
Reactive arthritis Microchapters |
|
Diagnosis |
|---|
|
Treatment |
|
Case Studies |
|
Reactive arthritis overview On the Web |
|
American Roentgen Ray Society Images of Reactive arthritis overview |
|
Risk calculators and risk factors forReactive arthritis overview |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]
Overview
Reactive arthritis (ReA) is an autoimmune condition that develops in response to an infection in another part of your body. Coming into contact with bacteria and developing an infection can trigger reactive arthritis. Reactive arthritis has symptoms similar to arthritis or rheumatism. It is caused by another disease, and is thus "reactive", i.e., dependent on the other condition. The "trigger" infection is typically missing in the chronic case.
Reactive arthritis is the combination of three seemingly unlinked symptoms—an inflammatory arthritis of large joints, inflammation of the eyes (conjunctivitis and uveitis), and urethritis. A useful mnemonic is "the patient can't see, can't pee and can't climb a tree". It is also known as arthritis urethritica, venereal arthritis and polyarteritis enterica. It is a type of seronegative spondyloarthropathy.
Reactive arthritis is an RF-seronegative, HLA-B27-linked spondyloarthropathy (autoimmune damage to the cartilages of joints) often precipitated by genitourinary or gastrointestinal infections.
It most commonly strikes individuals aged 20-40, it is more common in men than in women, and more common in white men than in black men. This is due to white individuals being more likely to have tissue type HLA-B27 than black individuals. People with HIV have an increased risk of developing reactive arthritis as well. Food poisoning is a common cause.
Historical Perspective
In fourth century B.C, Hippocrates was the first to associate the presence of arthritis and infection in the genitourinary tract. In 1818, Sir Benjamin Brodie, an English physician was the first to describe the triad of urethritis, arthritis, and conjunctivitis. In 1916, several reports from France & Germany showed association between diarrhea and post-infection arthritis.
Classification
Reactive arthritis (ReA) can be classified on the basis of previous gastrointestinal (GI) or genitourinary (GU) infection in to venereal or dysenteric ReA.
Pathophysiology
It is thought that reactive arthritis is the result of previous gastrointestinal or genitourinary infections, which results in an autoimmune condition. The most commonly associated organisms include Chlamydia, Yersinia, Salmonella, Shigella, and Campylobacter infection. It is estimated around 75% patients of reactive arthritis are positive for HLA-B27. The exact mechanism by which infecting organism cause reactive arthritis is not fully understood. It is thought that microbial antigens are similar to certain body proteins (self proteins). When an immune response is mounted against the microbial proteins, the antibodies produced against microbial proteins also reacts with the self proteins of the body causing reactive arthritis.
Causes
Common causes of reactive arthritis include infection with Chlamydia trachomatis, Neisseria gonorrhoeae, Salmonella enteritidis, Shigella flexneri, Campylobacter jejuni, Mycoplasma pneumoniae, Lymphogranuloma venereum, Mycobacterium tuberculosis, Clostridium difficile, and Streptococci viridans.
Differentiating Reactive arthritis overview from Other Diseases
Reactive arthritis should be distinguished from other HLA-B27 diseases causing arthritis of the peripheral skeleton, which present as arthralgia. The differentials include psoriatic arthritis, rheumatoid arthritis and ankylosing spondylitis.
Epidemiology and Demographics
The incidence of reactive arthritis following a gastrointestinal or genitourinary infection is approximately 3-27 cases per 100,000 individuals worldwide. The prevalence of reactive arthritis is approximately 30-40 cases per 100,000 individuals worldwide. Reactive arthritis commonly affects young adults in the age group of 18-35 years of age. Men are more commonly affected with reactive arthritis than females with male to female ratio of approximately 4:1. There is no racial predilection to reactive arthritis.
Risk Factors
Common risk factors in the development of reactive arthritis include abnormal joint structure (most important risk factor), male sex (four times more likely) rheumatoid arthritis, diabetes mellitus, malignancy, old age, use of systemic steroids, HIV infection, hemodialysis, previous joint surgery and injection drug abuse.
Screening
There is insufficient evidence to recommend routine screening for reactive arthritis.
Natural History, Complications, and Prognosis
If left untreated, patients with reactive arthritis may progress to develop myalgias and joint pain especially in the lower extremities. Over the course of time, patient develops urethritis and conjunctivitis. Complications of reactive arthritis are seen with chronic course and may include chronic arthritis with remitting relapsing course, urethral stricture, vitreous floaters, macular edema, cataracts or glaucoma, ankylosing spondylitis, and aortitis. Prognosis is generally good for patients with reactive arthritis. Patients who receive and respond to treatment generally have rapid reversal of symptoms. It is estimated that around 25% of patients may develop long term complication of arthropathy.
Diagnosis
Diagnostic Criteria
Reactive arthritis is diagnosed based on the clinical presentation with supporting laboratory evidence. The gold standard for diagnosis of reactive arthritis include spondyloarthritis and clear evidence of preceding infection by culture or polymerase chain reaction.
History and Symptoms
Obtaining history is an important aspect in making a diagnosis of reactive arthritis. The areas of focus should be on onset, duration, and progression of symptoms with special focus on past medical history and current medications. Previous history of gastrointestinal or genitourinary infections may predispose an individual to develop reactive arthritis. Symptoms start to appear after days to weeks of initial gastrointestinal or genitourinary infection. Common symptoms of reactive arthritis include urinary changes (increased frequency, dysuria/burning micturation and urgency), irritation and redness of eyes, and joint pain (arthralgia-commonly of lower limbs). Less common symptoms include inflammation of soft tissue, swollen toes, and skin rash. If symptoms are present for more than six months, it is termed as chronic reactive arthritis.
Physical Examination
Physical examination of patients with reactive arthritis is usually remarkable for arthritis (lower extremity; weight bearing), conjunctivitis, and urethritis. As the duration and severity of reactive arthritis increases other signs include dactylitis (sausage-shaped fingers), enthesopathy, sacroiliitis, keratoderma blennorrhagicum, circinate balanitis, myocarditis, and pericarditis.
Laboratory Findings
Laboratory findings consistent with the diagnosis of reactive arthritis include elevated erythrocyte sedimentation rate (ESR), elevated C-reactive protein (CRP), and elevated total leukocyte count (TLC) showing increased polymorphonuclear cells (PMNs). Synovial fluid or synovial membrane biopsy for detection of bacterial DNA by polymerase chain reaction (PCR) or immunofluorescence microscopy.
Imaging Findings
An x-ray may be helpful in the diagnosis of reactive arthritis. Reactive arthritis primarily involves the lower extremities and an x-ray of hip with sacroiliac joint, knees, ankles and feet may show juxta-articular osteoporosis, soft tissue swelling, bilateral asymmetric distribution uniform joint space loss, and bone proliferation.
MRI of the affected joints may be helpful in the diagnosis of reactive arthritis. Findings on MRI suggestive of reactive arthritis include bone edema, bone erosion and bony proliferation.
Ultrasound may be helpful in the diagnosis of reactive arthritis. Findings on an ultrasound suggestive of reactive arthritis include thickening of synovial sheath, synovial tendon and increased volume of synovial fluid.
Other Diagnostic Studies
There are no other diagnostic studies associated with reactive arthritis.