Ankylosing spondylitis Flashcards
Is the whole skeleton affected by ankylosing spondylitis?
No
Characterised by chronic inflammation of axial skeleton/spine
Which characteristic feature of ankylosing spondylitis occurs due to chronic inflammation of the axial skeleton?
Stiffening and fusion (ankylosing) of vertebral column and sacroiliac joints
How is ankylosing spondylitis related to axial spondyloarthropathies?
Ankylosing spondylitis is the radiographic subset of axial spondyloarthropathies
Radiographic-axSpa
Is ankylosing spondylitis equally common in men and women?
Higher prevalence in men
At what age are people typically diagnosed with ankylosing spondylitis?
Under 40 yrs old
At what age do most people with ankylosing spondylitis develop initial symptoms?
Under 30 yrs old
Does ankylosing spondylitis typically have a rapid or insidious onset?
Insidious onset
What is the initial stage of ankylosing spondylitis, and what cells are typically present?
Enthesitis of spinal ligaments with chronic inflammation characterised by presence of CD4, CD8 lymphocytes and macrophages
What are syndesmophytes, and why do they form after enthesitis, in AS?
Bony outgrowths from spinal ligaments
TNF-alpha and TGF-beta cytokines at sites of enthesitis promote fibrosis and ossification on top of old enthesis so that new enthesis forms: syndesmophyte
Give 2 examples of cytokines that characteristically promote syndesmophyte formation in ankylosing spondylitis?
TNF-alpha
TGF-beta
What causes vertebrae to appear square-shaped in ankylosing spondylitis, and what characteristic AS term is used to describe the spine now?
Supraspinous and interspinous ligaments have progressive calcification (dagger sign), so vertebrae appear square: bamboo spine
In ankylosing spondylitis, what is the most common initial symptom?
Low back pain and stiffness
In ankylosing spondylitis, what improves and exacerbates the low back pain and stiffness?
Improves with exercise
Exacerbated by staying still and not moving
In ankylosing spondylitis, is the severity of the low back pain and stiffness steady throughout the day?
No
Worst in morning upon waking (EMS), improves during day with movement, worst again at night when resting
What effect does ankylosing spondylitis have on normal posture?
Commonly causes hyperkyphosis: Excessive outwards curvature of spine
Most common in thoracic spine (thoracic hyperkyphosis)
What term is used to describe the shape of the back in ankylosing spondylitis, due to hyperkyphosis?
Hunchback: head in front of hips/pelvis when standing, hips flexed
Why might a patient with ankylosing spondylitis find it painful to sit?
Tenderness over ischial tuberosities
Why might a patient with ankylosing spondylitis find it painful to sleep on their side?
Tenderness over iliac crests
Give 3 pelvic areas where people with ankylosing spondylitis are often tender?
Iliac crests
Ischial tuberosities
Pelvic brim (bony edge of pelvic ring)
Why might a person with ankylosing spondylitis have a limp or cautiously place feet when walking?
Tenderness in heels
Which neurological condition is a medical emergency, and a complication of ankylosing spondylitis?
Cauda equina syndrome
How can ankylosing spondylitis affect the heart?
Complication of aortic regurgitation: reverse blood flow from the aorta into the left ventricle (LV) during diastole
If ankylosing spondylitis causes enthesitis of costosternal and costovertebral muscles, what 3 lung complications can occur?
Pleuritic chest pain
Pulmonary fibrosis
Restricted chest movement (eg. pain during inspiration)
What criteria is used to diagnose ankylosing spondylitis?
Modified New York criteria 1984
According to the Modified New York criteria 1984, how many clinical and radiological findings must a person have to be diagnosed with AS?
At least 1 out of 3 clinical criteria
Must have the radiological criteria: Sacroiliitis grade ≥2 bilaterally, or grade 3 to 4 unilaterally.
In the Modified New York criteria 1984, what are the 3 possible clinical findings to diagnose AS?
Low-back pain and stiffness for longer than 3 months, which improve with exercise but are not relieved by rest
Restriction of motion of the lumbar spine in both the sagittal and frontal planes
Restriction of chest expansion relative to normal values correlated for age and sex
What are the 4 characteristic radiological signs of ankylosing spondylitis?
Dagger sign: calcification of the supraspinous and interspinous ligaments in vertebral column
Bamboo spine: Advanced ankylosing (fusion) of vertebrae makes spine look like straight column
Sacroiliitis
Shiny corner sign: Reactive sclerosis secondary to romanus lesions: Inflammatory erosion of corners of superior and inferior endplates of vertebral bodies
When does bamboo spine develop in the progression of AS?
Advanced AS, when inflammation has been untreated for a long time
Describe the shiny corner sign, and is this better seen on plain film or MRI, in AS?
Reactive sclerosis secondary to Romanus lesions: inflammatory erosions at the corners of superior and inferior endplates of the vertebral bodies
Better seen on MRI
Which part of the spine most commonly has limited motion, in presentation of AS?
Limited lumbar spine motion
What nonpharmacological management is used in AS to prevent spinal fusion in a flexed position?
Spinal extension exercises and physiotherapy
In very severe AS, what surgery is recommended?
Spinal osteotomy: Techniques used to correct spinal deformity
What is the first-line drug class to treat AS, and at what dosage?
NSAIDs at lowest effective dose, increase if needed and switch to other NSAID if not effective at max. Tolerated dose for 2-4 weeks
What is the second-line drug class to treat AS, and give common examples, and why are they used instead of NSAIDs?
Conventional DMARDs eg. sulfasalazine, methotrexate
Or biological DMARDS eg. adalimumab, etanercept, infliximab
Given if NSAIDs ineffective/not tolerated
What is the third-line drug class to treat AS, and give common examples, and why are they used instead of DMARDs?
Monoclonal antibodies/interleukin-17 inhibitors eg. secukinumab, ixekizumab
Given if anti-TNF biologics are ineffective/not tolerated
