- Clinical science
Reactive arthritis, (formerly known as Reiter's syndrome), is an autoimmune condition that occurs after a bacterial infection of the gastrointestinal or urinary tract. It is categorized as a seronegative spondyloarthritis because of its association with HLA-B27. Reactive arthritis primarily affects young men and usually presents with musculoskeletal or extra‑articular symptoms. The characteristic triad consists of arthritis, conjunctivitis, and urethritis. The diagnosis is based on clinical features such as patient history and physical examination; there are no specific tests for reactive arthritis. Treatment is primarily symptomatic and consists of the administration of NSAIDs, as most patients recover spontaneously.
- Latency period: 1–4 weeks
- Acute onset
- Often asymmetrical with a migratory character
- Occurs predominantly in the lower extremities
- Extra‑articular symptoms
- Symptoms from preceding infection
Can't see, can't pee, can't climb a tree!
- Reactive arthritis is a clinical diagnosis that may be supported by diagnostic steps, but there is no confirmatory test.
- Laboratory tests
Arthrocentesis: may be performed to rule out differentials . Findings from synovial fluid analysis include:
- ↑ WBC count: 10,000-40,000/μL
- Mostly polymorphonuclear leukocytes predominate
- Gram stain and cultures are negative
|Differential diagnoses of infection-associated arthritis|
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Onset and course
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Pattern of disease
The differential diagnoses listed here are not exhaustive.
There is no curative treatment. The goal of treatment is to primarily control symptoms as the disease is usually self-limiting.
- Treat extraintestinal manifestations as necessary.
- Resolves spontaneously within a year (80% of cases)
- High rate of recurrence (15–50% of cases)