Ankylosing Spondylitis

Question 1

What is Ankylosing Spondylitis?

Answer 1

A functional syndrome associated with joint pain and any accompanying loss of function. It is characterised by loss of cartilage, remodelling of adjacent bone and inflammation in the spine.

It is part of a group of inflammatory conditions (Seronegative arthropathies), which share similar clinical features, pathological findings, the absence of rheumatoid factor and a strong association with the histocompatibility antigen HLA-B27.

They comprise:
Ankylosing spondylitis
Psoriatic arthropathy
Reactive arthritis - Aseptic inflammation of joints following infection

These conditions share many common clinical features

Question 2

What are the causes of Ankylosing Spondylitis?

Answer 2

No known cause

Question 3

What will you find on history taking of Ankylosing Spondylitis?

Answer 3

Specific Symptoms: - Inflammatory back pain, not mechanical!
Low back/buttock pain/Thoracic Pain
Morning Stiffness lasting >30 mins
Improved with exercise
Localised sacroiliac tenderness
Pain worse at night - Can be woken in the night with the pain

Seronegative Symptoms:
Peripheral asymmetrical large joint oligoarthritis (2-4 joints)
Achilles tendinitis
Plantar fasciitis
Uveitis  - Red painful eyes 
Aortitis
Prostatitis 

Risk Factors:
Age < 30
Affects men more than women

Specific Questions to ask:
Make sure to find out effect on life
Need to exclude red flag symptoms for spinal lesions e.g. cancer - Age >55, Trauma, Weight loss, Neuro symptoms, Atypical pain, Systemic infective features, Steroid use, History of cancer

Differentials:
Psoriatic Arthritis - Associated with psoriasis
Reactive Arthritis - Urethritis, Arthritis, conjunctivitis post infection
Osteoarthritis - Presents with mechanical pain typically becoming worse at the end of the day and after activity, with no morning symptoms
Bony Mets - Weight loss, alarm signs

Question 4

What will you find on examination of Ankylosing Spondylitis?

Answer 4

End of the bed:
Change in gait – Achilles tendonitis/Stiffness
Stand straight against wall – late stage can’t do this as loss of lordosis - Question mark posture

Hands:
Look for Dactylitis that would indicate psoriatic arthritis

Chest:
Reduced Schobers test  -Centre of dimples of venus, 10cm above and 5cm below, should increase >5cm on forward flexion 
Loss of movement in all directions 
Reduced chest expansio
Tenderness at sacroiliac joints

Legs:
Change in gait – Achilles tendonitis/Stiffness
Tenderness over the heel (either plantar fascia or Achilles tendon)

Question 5

What investigations will you order in Ankylosing Spondylitis?

Answer 5

Bloods:
FBC
HLA-B27 - Raised in 90%
ESR/CRP - Raised in 50%
Rheumatoid Factor - Will be negative. To rule out rheumatoid arthiritis 

Imaging:
X-rays - juxta-articular sclerosis, erosions and widening of the sacroiliac joints, bamboo spine and eventually ankylosis (fusion), but they are insensitive to early disease. May also show sacroiliitis
Foot X-ray -Calcaneal spur if any plantar fasciitis
MRI - Can show earlier changes

Question 6

What is the treatment of Ankylosing Spondylitis?

Answer 6

Refer to rheumatologist

Lifestlye:
Intense physiotherapy and hydrotherapy.

Medical:
1st line - NSAIDS For Axial Disease
2nd Line -Anti TNF Alpha for severe disease
Methotrexate or sulfasalazinefor peripheral joint arthritis
Topical corticosteroids for uveitis.
Intra-articular steroids for localised peripheral synovitis and for refractory sacroiliitis; local steroids also for plantar fasciitis/Achilles tendonitis