Spondylarthropathies Flashcards
Defing spondylarthropathies?
Family of inflammatory arthritides characterized by inv. of both the spine and joints, principally in genetically predisposed (HLA-B27 +ve) individuals
Types of spondylarthropathies?
- Ankylosing spondylitis
- Enterpathic arthritis
- Reactive arthritis (Reiter’s syndrome is part of this)
- Psoriatic arthritis
Usefulness of HLA-B27 screening?
Autosomal dominant inheritance but the background prevalence varies depending on location
It is not a useful screening/diagnostic test, unless the patient has symptoms as well
Compare the symptoms of mechanical and inflammatory back pain?
Mechanical:
• Worsened by activity and better with rest
• Typically worse at the end of the day
Inflammatory:
• Worsened by rest and better with activity
• Significant early morning stiffness (> 30 mins)
Rheumatological features that are shared by all spondylarthropathies?
Sacroiliac and spinal inv.
Enthesitis (inflammation at insertion of tendons into bones), e.g: Achilles tendonitis or plantar fasciitis
Inflammatory arthritides that are oligoarticular, asymmetric and mostly affect the lower limb
Dactylitis can occur (inflammation of entire digits) and results in “sausage fingers/toes”
Extra-articular features shared by the spondylarthropathies?
- OCULAR INFLAMMATION (anterior uveitis, conjuntivitis)
- Mucocutaneous lesions
- Rarely, aortic incompetence or heart block
- NO RHEUMATOID NODULES
What is ankylosing spondylitis?
Chronic systemic inflammatory disorder that primarily affects the spine
Occurrence of ankylosing spondylitis?
Tends to be late adolescence or early adulthood
It is more common in men (
Hallmark of ankylosing spondylitis?
Sacroiliac joint involvement (sacroiliitis)
Peripheral arthritis (shoulder and hip) is uncommon
Enthesitis
What are the features of spondylarthropathies (SpA)?
- Inflammatory back pain (neck, thoracic, lumbar, etc)
- Peripheral arthritis (shoulders, hips), enthesitis, uveitis, dactylitis
- Psoriasis
- Crohn’s/colitis
- Good response to NSAIDs
- FH of SpA
- HLA-B27
- Elevated CRP
Define the diagnosis of SpA with the ASAS classification?
Sacroiliitis on imaging AND ≥ 1 SpA feature
OR
HLA-B27 +ve AND ≥ 2 SpA features
Extra-articular features of ankylosing spondylitis?
- Anterior uveitis
- CV inv.
- Pulmonary inv. (e.g: fibrosis of upper lobes)
- Asymptomatic enteric mucosal inflammation
- Neurological inv. (rarely, A-A subluxation)
- Amyloidosis (deposition of abnormal proteins)
What are the 7 As of ankylosing spondylitis?
Axial arthritis Anterior uveitis Aortic regurgitation Apical fibrosis Amyloidosis/Ig A neuropathy Achilles tendonitis PlAntar fasciitis
Describe what occurs in a spine with ankylosing spondylitis
Syndesmophytes (fusion of vertebrae) leads to question mark posture
Examination of a patient with ankylosing spondylitis?
Tragus/occiput to wall (straighten the neck while pressed against a wall)
Chest expansion (to check if fusion of the costovertebral joints had occurred)
Modified Schober test (bend to check lumbar flexure)
Blood tests for ankylosing spondylitis?
Inflammatory proteins (ESR, PV and CRP) are raised
HLA-B27 (may/may not be +ve)
X-rays search for what in ankylosing spondylitis?
Sacroiliitis
Syndesmophytes
“Bamboo” spines
Limitations of X-rays?
Usually show changes after a long period of time, e.g: late changes inc. sacroiliac sclerosis, vertebral fusion and erosions
Differences between signs seen on a spinal X-ray in ankylosing spondylitis and osteoarthritis
In AS:
• Bone density is normal in early stages but reduced in late disease
• Shiny corners due to initial syndesmophyte formation
• Flowing syndesmophytes
• Fusion forms a “bamboo spine”
In OA: • Bone density is normal • Reduced joint space • Subchondral sclerosis • Sunchondral cyst formation • Osteophyte formation assoc. with neural foraminal narrowing