Spondyloarthropathies Flashcards
What is the definition of spondyloarthropathy?
What are the four main types?
A family of inflammatory arthritides characterized by involvement of both the spine and joints, principally in genetically predisposed (HLA B27 positive) individuals The four types are: - Ankylosing spondylitis - Enteropathic arthritis - Reactive arthritis - Psoriatic arthritis
Which antigen is associated with spondyloarthropathy?
HLA B27
Note - not a useful screening or diagnostic test unless patients also have symptoms
What are the clinical diffferences between mechanical and inflammatory joint pain?
Mechanical - worsened by activity, typically worst at end of day, better with rest
Inflammatory - worse with rest, better with activity, significant early morning stiffness (>30 minutes)
Ankylosing spondylitis
What is it?
Who is the typical patient?
This is a chronic systemic inflammatory disorder that primarily affects the spine and sacroiliac joints.
The typical patient is a man <30 years old with gradual onset of low back pain, worse at night, with spinal morning stiffness relieved by exercise. Pain radiated from sacroiliac joints to hip/buttocks and usually improves towards the end of the day. There is progressive loss of spinal movement.
Anterior mechanical chest pain can also occur due to costochondritis and fatigue may feature.
What is the ASAS classification criteria for axial spondyloarthritis?
Patient must either have 1 or 2:
- Sacrolitis on imaging AND ≥1 SpA feature
- HLA-B27 positive AND ≥2 other SpA features
SpA features:
- Inflammatory back pain
- Arthritis
- Enthesitis (heel)
- Uveitis
- Dactylitis
- Psoriasis
- Crohn’s/colitis
- Good response to NSAIDs
- Family history of SpA
- HLA-B27
- Elevated CRP
What are some clinical features of AS?
Back pain – neck, thoracic, lumbar
Enthesitis – especially Achilles tendonitis, plantar fasciitis, at the tibial and ischial tuberosities and at the iliac crests
Peripheral arthritis (shoulder’s, hips) – rare
Extra-articular features:
Anterior uveitis
Cardiovascular involvement (aortic valve/root )
What happens to the spine over time is AS?
You get fusion of the vertebrae called syndesmophytes, causing a deformed back as shown opposite.
How can you diagnose AS?
Diagnosis is clinical, supported by imaging (MRI is most sensitive and better at detecting early disease). Sacroliitis is the earliest x-ray feature, but may appear late.
Bloods show raised inflammatory markers, and commonly HLA B27
Describe the Schober test
Schober test – While the patient is in a standing position the examiner makes a mark approximately at the level of L5 (fifth lumbar vertebra). Two points are marked: 5 cm below and 10 cm above this point (for a total of 15 cm distance). Then the patient is asked to touch his/her toes while keeping the knees straight. If the distance of the two points do not increase by at least 5 cm (with the total distance greater than 20 cm), then this is a sign of restriction in the lumbar flexion. This can be useful in examining a patient suspected of ankylosing spondylitis.
Describe some differences between an AS spine vs an OA spine
AS - Bone density - normal in early disease, reduced in late disease - Shiny corners - Flowing Syndesmophytes - Fusion (Bamboo spine) OA - Normal bone density - Reduced Joint space - Subchondral sclerosis - Subchondral cyst formation - Osteophyte formation Associated with neural foraminal narrowing
Give some possible treatments for AS
Physiotherapy – to maintain posture and mobility
Occupational therapy
NSAID – these are a starting point for treatment – they lower pain and may slow radiographic progression
Disease modifying drugs. SZP, MTX – if also peripheral joint involvement
Anti TNF treatment – Infliximab, Certolizumab,
Define psoriatic arthritis
Inflammatory arthritis associated with psoriasis, but 10 -15% of patients can have PsA without psoriasis (this is where the joints are affected first) so it is important to ask about family history of familial psoriasis.
What are some common features of psoriatic arthritis?
Inflammatory Arthritis (5 subgroups/ presentations)
Sacroiliitis: often asymmetric, may be associated with spondylitis
Nail involvement (Pitting, onycholysis)
Dactylitis
Enthesitis: achilles tendinitis, plantar fasciitis
Extra articular features (eye disease)
What is the typical pattern of joint involvement in psoriatic arthritis?
Symmetrical polyarthritis (like RA)
DIP joints
Asymmetrical oligoarthritis
Spinal (similar to AS)
What two things could you test blood for in PsA?
Inflammatory parameters (raised) Negative RF – check rheumatoid factor of joint involvement is symmetrical and you’re not sure if it could be RA
