Ankylosing Spondylitis

Exam Cram

• Ankylosing spondylitis is a seronegative inflammatory arthropathy, 

• Presents with lower back pain > 30 mins in morning, better with exercise, under 45yrs old

• Investigations: seronegative (-ve antibodies), sacroiliitis on imaging, HLA B27 +ve

• Management: 1. NSAIDs;  2. TNF blockers- e.g. Etanercept, Adalimumab

Outline

Background 

Associations

• Anterior Uveitis

• Aortic Regurgitation

Diagnosis

Diagnostic criteria (modified New York 1984 criteria): 

Require all 3: Sensitivity and specificity 80%

1. 3m of back pain 

2. Under 45yrs

3. Sacroiliitis on XR/ MRI and one feature

OR

 3. HLA B27 and on two features

Ankylosing Features

• Inflammatory back pain

• Arthritis

• Enthesitis

• Uveitis

• Dactylitis

• Psoriasis

• Crohn's/ colitis

• Good response to NSAIDs

• Family history

• HLA B27

• CRP rise

Presentation

• < 45yrs 

• Morning lumbar back pain > 30 mins, better with movement

• Lumbar tenderness and reduced lateral and forward flexion

• Dactylitis, plantar fascitis

Investigations

• XR or MRI: sacro-illitis

• HLA B27 +ve

• Raised CRP/ ESR

Differentials

• Seronegative arthropathies- IBD arthritis, psoriatric arthritis, reactive arthritis

• MSK back pain

Management

1. NSAIDS (x2 regimes - regular), physiotherapy

2. Anti TNF monoclonal antibodies 

   1. 1. 1. Etanercept and Adalimumab with TB screening

         2. Golimumab

3. Rituxumab

Med Reg Notes

Common MCQ:  XR vs MRI

• Clinical practice would get XR prior to MRI but MRI of course more sensitive- key is question wording!

Comments: 

Infliximab (TNF alpha)

Prednisolone can provide short term relief but can increase risk of spinal osteoporosis, so usually avoided. 

Methotrexate not commonly used. 

Written in 2024.