Seronegative arthritis Flashcards
What does spondylarthritis refer to?
Involving the spine
What is the difference between mono, oligo, and polyarthrtis?
Mono: 1 joint
Oligo: 2-4 joints
Poly: 5+ joints
What is ankylosing spondylitis?
Predominantly axial disease
- Can affect peripheral joints which is classically an asymmetrical oligoarthritic affecting large joints
Which blood tests confirm rheumatoid arthritis?
- Anti-CCP: very sensitive to rheumatoid
- Rheumatoid factor: present in 70% but not specific
What is seronegative arthritis?
Ankylosing Spondylitis
Psoriatic Arthritis
Reactive Arthritis (Reiter syndrome)
Enteropathic (IBD related) Arthritis
What is HLA B27?
A protein found of surface of WBC’s associated with autoimmune disorders
What diseases are positive for HLA B27?
Ankylosing spondylitis – >90%
Reactive arthritis – 63-75%
Inflamm. bowel disease + spondylitis – 50%
Psoriatic arthritis with spondylitis – 50%
with peripheral arthritis – 15%
Anterior uveitis – 69-90%
Pustular psoriasis – 69-90%
Circinate balanitis – 69-90%
What is reactive arthrits?
It occurs usually 1-4 weeks after infection
- Classically follows and STI or diarrhoeal illness Eg, chlamydia, gonorrhoea, salmonella, shigella, campylobacter, Yesinia, C.diff
What is reiters triad?
The classic presentation of reactive arthritis (Reiter’s syndrome)
- Arthritis, urethritis, and conjuctivitis
What is Keratoderma Blennorrhagicum?
A thickening and keratinization of skin on the feet, hands, and nails that resemble psoriasis clinically and on histopathology
It’s a characteristic feature of reactive arthritis
What are the tests for suspected reactive arthritis?
- Aspirate and culture synovial fluid
- Urinalysis
- Stool culture
- STD screen – swabs
- HLA B27 / inflammatory markers
Consider:
- Blood cultures (esp. if gonococcal – can cause disseminated septic
arthritis)
- Throat swab / ASO titre
How is reactive arthritis managed?
- Investigate for cause
- Treat the cause cause and provide analgesia like NSAID’s
- Consider intraarticular or oral steroids
What are the complications of ankylosing spondylitis if left untreated?
Causes spinal fusion
- May go on to affect peripheral skeleton
What is the modified New York criteria used for?
Classification of ankylosing spondylitis
- Limited lumbar motion
- Low back pain > 3 months improved with exercise and
not relieved by rest - Reduced chest expansion
- Bilateral sacroiliitis (grade 2-4) on X-ray
- Unilateral sacroiliitis (grade 3-4) on X-ray
* Definite ankylosing spondylitis if criterion 4 or 5 plus 1,2 or 3
What are the extra-articular features of ankylosing spondylitis?
- Anterior uveitis/iritis
- Cardiovascular: aortic regurgitation / aneurysm, AV block
- Pulmonary: apical fibrosis,Chest wall restriction, Cauda equina syndrome, Enteric / mucosal lesions, Osteoporosis
