Ankylosing Spondylitis Flashcards
Define
Seronegative arthropathy affecting the axial skeleton and large proximal joints
Aetiology (gene association)
HLA-B27
infective triggers
Which joints are primarily affected? Where does the pain travel?
Lumbar - lower back
Then progress to thoracic and cervical regions (go up the back)
Epidemiology
Males>females, especially in young males
Symptoms (bone)
Lower back pain
Sacroiliac (hip) pain
Progressive loss of spinal movement
Describe the pain - when it is worsened, when it gets better
The pain disturbs sleep
Worse in the morning
Gets better with activity
Returns with rest
Other symptoms
Pleuritic chest pain
Heel pain
Malaise
Fatigue
What causes the pleuritic chest pain?
Costovertebral join involvement
What causes the heel pain?
Plantar fasciitis
What would you find on examination?
Decreasing range of spinal movement, especially hip rotation Decreased spinal flexion Tenderness over SI joints Thoracic kyphosis (spinal fusion)
What signs of extra articular disease might you see?
Anterior uveitis (red eye)
Apical lung fibrosis
Reduced chest expansion
Aortic regurgitation
Pathophysiology
Inflammation of vertebral discs and interfacet joint spaces, however NO autoantibodies have been found
What causes the limited range of motion? Which two cells are involved? What do you call the resulting product?
FIBROBLASTS, which normally produce collagen, now produce FIBRIN which firmly sticks the vertebral bones together, limiting movement.
Then OSTEOBLASTS cause ossification of these soft tissues, resulting in SYNDESMOPHYTES
What are syndesmophytes?
Hardened extra protrusions of vertebral bones, in between the vertebrae
Investigations
FBC (anaemia of chronic disease) RF (negative) Raised ESR/CRP CXR Lung function tests (assess impairment from kyphosis)
