Ankylosing Spondylitis

Question 1

Ankylosing Spondylitis

Answer 1

• chronic inflammatory autoimmune disease affecting the axial skeleton, specifically the sacroiliac joints and the spine
• most common in males aged 20-30 years
• related to HLA-B27 gene (but not 100% specific)

Question 2

Aetiology of ankylosing spondylitis

Answer 2

genetics:
- family hx.
- presence of HLA-B27 gene mutation

environment:
- infections (klebsiella)
- gut microbiota
- smoking

Question 3

Pathophysiology of ankylosing spondylitis

Answer 3

(affects intervertebral, facet, and sacroiliac joints)
1. initial inflammation via autoimmune reaction
2. reparative stage - new pathological bone formation

Question 4

Clinical features of ankylosing spondylitis

Answer 4

• typically a young male, insidious onset
• low back, buttocks, or neck pain
• stiffness (worse in morning, improves with exercise)
• pain at night
• weight loss, fever, fatigue, SOB (complication related effects)

Question 5

Clinical exam findings in ankylosing spondylitis

Answer 5

• reduced lateral flexion
• reduced forward flexion (schobers test)
• reduced chest expansion

Question 6

Complications of ankylosing spondylitis

Answer 6

• apical fibrosis (restrictive lung disease)
• aortic regurgitation
• anterior uveitis
• achilles tendonitis
• cauda equina syndrome
• inflammatory bowel disease

Question 7

Investigating ankylosing spondylitis

Answer 7

• Raised inflammatory markers (CRP, ESR)
• X-ray spine/pelvis

Question 8

X-Ray findings in ankylosing spondylitis

Answer 8

• sacroilitis
• subchondral erosions, sclerosis
• squaring of lumbar vertebrae
• ‘bamboo spine’

Question 9

Ankylosing spondylitis differentials

Answer 9

• mechanical back pain
• rheumatoid arthritis
• psoriatic arthritis

Question 10

Managing ankylosing spondylitis

Answer 10

• regular physical activity
• physiotherapy
• NSAIDs
• other (DMARDs, anti-TNF therapy)