Reactive arthritis

Definition

• A syndrome cause by specific infections in a genetically susceptible host that is characterized by conjunctivitis, urethritis, and seronegative arthritis

Associated Infections

• Enteric infections
  • Shigella spp.
  • Salmonella spp.
  • Yersinia enterocolitica and Y. pseudotuberculosis
  • Campylobacter jejuni
• Genitourinary infections
  • Chlamydia trachomatis

Clinical Presentation

• Classic triad of arthritis, urethritis, and conjunctivitis only seen in about a third of patients
• Onset 1-4 weeks after infection
• May present with constitutional symptoms (fever, malaise, weight loss)
• Arthritis is usually peripheral and axial, symmetric and additive evolving over 1-2 weeks
• Can have dactylitis, enthesistis, tendinitis, and fasciitis
• Oral ulcers are common but often asymptomatic
• Keratoderma blennorhagica, a palmoplantar pustular disease
• Circinate balanitis, painless erosions from ruptured vesicles on the glans

Investigations

• ESR/CRP and acute-phase reactants
• CBC may show mild anemia
• Synovial fluid non-specific inflammation
• X-rays can show justaarticular osteoporosis
  • Later findings include marginal erosions, loss of joint space, periostitis, reactive born formation, and plantar spurs

Management

• NSAIDs for symptom relief, though often not helpful
  • Indomethacin 75-150mg/d in divided doses

Prognosis

• Symptoms typically resolve over 3-5 months
• Can be chronic (about 15%)