Reactive Arthritis Flashcards
Definition
Characterised by a sterile arthritis occurring after an extra-articular infection
(commonly GI or urogenital).
Reiter’s’ syndrome
Reiter’s Syndrome is defined as a TRIAD of:
o Reactive arthritis
o Urethritis
o Conjunctivitis
Aetiology
- It is thought that initial activation of the immune system by a microbial antigen is followed by an autoimmune reaction that involves the skin, eyes and joints
- HLA-B27 allele is identified in 70-80% of patients
Associations
Associated with infections:
o GI • Salmonella • Shigella • Yersinia • Campylobacter
o Urogenital
• Chlamydia trachomatis (60%)
Epidemiology
- 20 x more common in MALES
- Age of onset: 20-40 yrs
- Seen in 2% of patients with non-specific urethritis
Presenting symptoms
- Symptoms can develop 3-30 days after infection
- Burning or stinging when passing urine (due to urethritis)
- Arthritis
- Low back pain (due to sacroiliitis)
- Painful heels (due to enthesitis and plantar fasciitis)
- Conjunctivitis
Signs on physical examination
• Signs of Arthritis
o Asymmetrical oligoarthritis
o Often affects the lower extremities
o Sausage-shaped digits
• Signs of Conjunctivitis
o Anterior uveitis - painful red eye
• Oral Ulceration
• Circinate Balanitis
o Scaling red patches on the glans (penis)
• Keratoderma Blenorrhagica o Brownish-red macules o Vesicopustules o Yellowish-brown scales o Found on the SOLES and PALMS
• Others
o Nail dystrophy
o Hyperkeratosis
o Onycholysis
Investigations (bloods)
o FBC
o High ESR and CRP
o HLA-B27 testing
Investigations
• Stool or Urethral Swabs and Cultures
o May be negative by the time the arthritis develops (because the arthritis occurs
post-infection)
• Urine
o Screen for Chlamydia trachomatis
• Plain X-Rays
o Useful in chronic cases
o Erosions seen at the entheses (insertion of tendons into bone)
• Joint Aspiration
o To exclude septic or crystal arthritis
