Reactive Arthritis: Presentation and Treatment
Clinical Presentation
Reactive arthritis typically presents as an acute or insidious mono-oligoarthritis of the lower limbs (particularly knee or ankle) occurring weeks after a genitourinary or gastrointestinal infection. 1, 2
Key Clinical Features:
- Asymmetric oligoarthritis affecting predominantly lower extremity joints (knees, ankles) 1, 3
- Triggering infections: Chlamydia trachomatis (urogenital), Salmonella, Shigella, Yersinia, or Campylobacter (enteric) 1, 3, 4
- Extra-articular manifestations: Enthesitis, tenosynovitis, bursitis, and dactylitis are frequent 1
- HLA-B27 positivity in over two-thirds of patients 4
- Duration: Typically weeks to several months, with 20% developing chronic disease lasting >1 year 3
Important Diagnostic Consideration:
- Reactive arthritis is the most common inflammatory polyarthritis in young men and may be the first manifestation of HIV infection 4
Treatment Algorithm
First-Line Therapy: NSAIDs and Local Measures
Start with high-dose NSAIDs as the cornerstone of initial treatment for all patients with reactive arthritis. 1, 3, 4
- NSAIDs at maximum tolerated doses are the most commonly used first-line agents 1
- Local measures: Arthrocentesis, cold pads, and rest of affected joints 3
- Intra-articular corticosteroid injection for large-joint involvement after ruling out infection 4
Antibiotic Therapy: Pathogen-Specific Approach
For Chlamydia-induced urogenital reactive arthritis with positive cultures, treat with doxycycline 100mg twice daily for 10-14 days (or azithromycin 1g single dose), and always treat sexual partners concurrently. 3, 4
Antibiotic Guidelines by Infection Type:
Urogenital (Chlamydia) Reactive Arthritis:
- If Chlamydia isolated: Doxycycline 100mg BID for 10-14 days OR erythromycin 500mg QID for 10-14 days OR azithromycin 1g single dose 3
- Treat sexual partners concurrently to prevent reinfection 3
- For culture-negative urogenital reactive arthritis: Consider 3-month antibiotic course, though evidence is limited and further studies needed 3
- Antibiotics may shorten disease course or abort onset when given early 4
Enteric Reactive Arthritis:
- Do NOT use antibiotics for enteric forms (Salmonella, Shigella, Yersinia, Campylobacter) as they show no benefit over placebo even with prolonged treatment 3, 4
Disease-Modifying Therapy for Persistent Disease
For reactive arthritis lasting >6 months despite NSAIDs, add sulfasalazine 2g/day as it is the only DMARD with proven efficacy in controlled trials. 1, 3
DMARD Selection Strategy:
First DMARD Choice:
- Sulfasalazine 2g/day is moderately superior to placebo in placebo-controlled studies and well-tolerated 3
- Continue NSAIDs concurrently 3
Second-Line DMARDs (for sulfasalazine failures):
- Methotrexate, azathioprine, or cyclosporine can be tried in individual patients unresponsive to sulfasalazine 1, 2
- Critical caveat: No controlled studies exist for DMARDs other than sulfasalazine, so carefully discuss risk-benefit ratio with patient before initiating 3
Corticosteroid Use
Systemic corticosteroids should be reserved for inflammatory symptoms resistant to NSAIDs, not as first-line therapy. 1
- Use when NSAIDs fail to control symptoms 1
- Intra-articular injection preferred for isolated joint involvement 4
Biologic Therapy for Refractory Cases
For aggressive cases unresponsive to conventional DMARDs, or when reactive arthritis evolves toward ankylosing spondylitis, TNF-alpha blockers (etanercept, infliximab) represent an effective choice. 1, 2
- TNF inhibitors (etanercept, infliximab) are highly effective in refractory cases 2
- Consider when conventional therapy fails or axial involvement develops 1
Common Pitfalls to Avoid
Do not use prolonged antibiotics for enteric reactive arthritis – no benefit demonstrated despite bacterial remnants in joints 3
Do not delay DMARD therapy beyond 6 months if arthritis persists despite NSAIDs 3
Always screen for HIV in young men presenting with reactive arthritis, as it may be the initial manifestation 4
Do not forget to treat sexual partners in Chlamydia-induced cases to prevent reinfection 3
Recognize that up to 20% develop chronic disease requiring long-term DMARD therapy 3