Axial Spondyloarthritis and Psoriatic Arthritis Flashcards
How is axial spondyloarthritis classified?
3/12 of inflammatory back pain with onset at age than less than 45 years plus either sacrolititis on imaging and >1 SpA feature OR HLA-B27 positive and > 2 other SpA features
What are the SpA features?
inflammatory back pain arthritis enthesitis uveitis dactylitis psoriasis crohn's/colitis good response to NSAIDs family history HLA-B27 elevated CRP
How is peripheral spondyloarthritis classified?
peripheral arthritis or enthesitis or dactylitis PLUS at least one of (uveitis, psoriais, colitis, preceding infection, HLA-B27, sacrolitis on imaging) OR at least two of (arthritis, enthesitis, dactylitis, inflammatory back pain, FHx)
What conditions are classified as spondyloarhtritides?
Ankylosing spondylitis, undifferentiated SpA, Juvenile SpA, arthritis associated with UC/crohn’s, reactive arthritis, acute anterior uveitis, psoriatic arthritis
What is inflammatory back pain?
Back pain that occurs at age of less than 40 with a gradual onset, improvement with exercise, pain at night that improves when getting up
Which genes are involved in axSpAs?
HLA-B27, HLA-B40, ERAP1
What is a characteristic feature of the spondyloarthropathies?
bone remodelling occurs as well as damage
What are the clinical features of axial spondyloarthritis?
inflammatory back pain, alternating buttock pain, restriction in spinal movement, extra axial MSK features, extra articular features
What are the extra axial MSK features of axial spondyloarthritis?
Peripheral arthritis - in an asymmetric oligoarthritis pattern, and enthesitis
What are the extra articular features of axial spondyloarthritis?
anterior uveitis, IBD, psoriasis, apical fibrosis, aortic regurgitation
How common is axial spondyloarthritis?
0.5-1% of population
When is onset of symptoms of axial spondyloarthritis?
3rd decade of life
What percentage of people with the HLA-B27 gene will develop an axial spondyloarhtitis?
5%
What investigations should be done when axial spondyloarthritis is suspected?
HLA-B27, inflammatory markers, XR (sacro iliac joints, cervical and thoraco-lumbar spine), MRI
What percentage of people with AS are positive for HLA-B27?
90%
What is the difference between non radiographic axial spondyloarthritis and ankylosing spondylitis?
they are a spectrum of the same disease - non radiographic patients go on to develop AS over time (after 20 years 85% will have developed AS), patients have same levels of pain however patients with AS have more imapired spinal mobility and chest expansion
What does sacrolitis look like on plain XR?
normal in early disease, early changes: erosions, sclerosis at margins, later: pseudo-widening, last: joint space narrowing progressing to ankylosis
What does the spine look like on plain XR in ank spond?
squaring of the vertebrae, romanus lesion (shiny corner), syndesmophyte. In late stages can have fractures and fusion of facet joints
What are the features of sacro-iliitis on MRI?
active inflammation (subchondral bone marrow oedema), synovitis, enthesitis, post inflammatory lesions (erosions, sclerosis, ankylosis, fatty lesions)
What are the features in a spine MRI in axial spondyloarthritis?
bone marrow oedema at vertebral corners, erosions, spondylodiscitis
Which MRI sequence is best for visualising subchondral bone marrow oedema?
STIR sequence
What predicts radiographic progression?
active inflammation and smoking
What is first line therapy for axial spondyloarhtiritis?
NSAIDs and non pharmacologics e.g. exercise
Are NSAIDs disease modifying?
yes
What is the indication for sulfasalazine and methotrexate?
peripheral manifestations (arhtritis, enthesitis, dactylitis)
Are conventional synthetic DMARDs (sulfasalazine and methotrexate) effective for spinal inflammation?
no
What is the second line therapy for axial spondyloarthritis?
TNF alpha blockers or IL-17 blockers
Should NSAIDs be used continuosly or PRN?
depends on risk vs benefit
Which patients are the best candidates for biologic therapies?
young, shorter disease duration, higher inflammatory markers, worse inflammation on MRI, less functional impairment, HLA-B27 positive
Which patients qualify for biologic therapy in Australia?
patients who have failed 12 weeks of NSAIDs and exercise and still have active disease
Which biologic therapies are beneficial in axial spondyloarthropathies?
all TNF inhibitors and IL-17 inhibitors
Are IL-12 and IL-23 blockers effective?
no
Which biologic is available on the PBS for non radiographic axial spondyloarthritis?
golimumab
Do biologic therapies stop XR progression?
not within first 2 years but yes after 2 years
What percentage of patients with psoriasis develop psoriatic arthritis?
15%
What are the 5 different patterns of joint involvement in psoriatic arthritis?
- asymmetric oligoarthritis (most common)
- symmetric polyarthritis
- axial AS like
- distal interphalyngeal joint with nail diease
- arthritis mutilans
What is dactylitis?
swelling along the entire length of digit - tendon and joint inflammation
What are the nail changes in psoriatic arthritis?
pitting, onycholysis and nail plate crumbling
What comorbidities are commonly seen in psoriatic arthritis?
CV disease, depression, metabolic syndrome
What investigations should be ordered in psoriatic arhtritis?
there are no biomarkers/antibodies and CRP/ESR only go up in about 40% of patients, RF and CCP are usually negative, can look at XR
What are the characeristic XR findings of psoriatic arhtirits?
pencil in cup deformity, erosions, new bone formation
can also get ankylosis and sacro-iliitis
What are the treatment options for psoriatic arthritis?
NSAIDs for symptom relief, methotrexate, sulfasalazine, leflunomide, biologics (anti-TNF, anti-IL17, IL12/23 blocker, JAK1/3 inhibitor)
In which patients should IL-17 blockers be avoided?
patients with IBD
What is reactive arthritis?
a sterile arthritis following a remote infection
Which are the causative organisms in reactive arthritis?
chlamydia, shigella, salmonella, campylobacter, yersinia
How long before the arthritis do patients have the infection in reactive arhritis
1-4 weeks
How do you treat reactive arthritis?
treat the infection, anti inflammatories for symptom relief, consider glucocorticoid if unwell
How long does reactive arhrtitis last?
3-5 months
Which patients should you use a DMARD in for reactive arthritis?
If it lasts longer than 5 months
What percentage of patients with IBD get spondyloarthritis?
10%
How should IBD associated spondyloarthritis be treated?
NSAIDs, DMARDs, controlling bowel disease, anti-TNF