spondyloarthropathies Flashcards
Group of inflammatory rheumatic diseases
Ankylosing spondylitis (AS).
Psoriatic arthritis (PsA).
Reactive arthritis.
Enteropathic arthritis (associated with inflammatory bowel disease).
what is spa
SpA predominantly affecting the spine and/or sacroiliac joints, i.e. axial spondyloarthritis. (axial skeleton: head, rib cage and spine): resulting in the main symptom of chronic back pain. E.g. AS
SpA predominantly affecting peripheral joints, i.e. peripheral spondyloarthritis. E.g. PsA, reactive arthritis, enteropathic arthritis.
Can include systemic involvement (extra-articular): heart, skin, lungs, eyes (inflammatory eye disease: uveiitis); also: fever, fatigue, etc.
Prevalence of SpA as a group is <2%, making it as common as RA:
what is Ankylosing spondylitis (AS)
Characterised by chronic inflammation of the axial skeleton and large peripheral joints.
Relatively common condition (200K people affected in UK) but severe cases of AS are relatively rare (~ 0.15%):
More common in men (2.5-3:1).
Insidious onset: presents as morning back stiffness/pain (>30mins) in young adults (usually develops in 20s-30s). Pain can improve with exercise, worse after rest.
Inflammation of sacroiliac joint (sacroiliitis) moves up the spine leading to symptoms.
Progression of disease leads to spinal fusion (ankylosis) that decreases spinal movement and can lead to spinal kyphosis, sacroiliac joint fusion, neck hyper-extension and rotation.
how is as diagnosed
Correct and early diagnosis of AS is challenging:
Diagnosis of axial spondyloarthritis (which includes AS and non-radiographic axial SpA) can be delayed by ~8 years (from when symptoms start).
89% of patients with axial spondyloarthritis have inflammatory back pain.
59% of people with axial spondyloarthritis report suffering mental health problems (compared to 25% of those with musculoskeletal conditions).
Refer to a rheumatologist if low back pain started before age of 45 years and has lasted for >3 months (subject to other criteria being present e.g. improvement with movement).
Diagnosis – Modified New York Criteria
Clinical and radiological criteria – sacroilitis on X-ray, back pain for >3 months, reduced spinal movement, limited chest expansion
AS management:pharmacological treatments
diagnosed with AS
1st line
Analgesics (for pain relief): offer oral NSAIDs* (for those with axial spondyloarthritis). Consider gastroprotective treatment (PPI).
If NSAID insufficient for pain relief, even after dose escalation (2-4week period)
Consider switching to another NSAID
Treat severe active AS in adults who have responded inadequately to, or who cannot tolerate, NSAIDs
Recommend biological DMARD * *: adalimumab, certolizumab pegol, etanercept, golimumab or infliximab (if within their marketing authorisations).- Start treatment with least expensive infliximab product.
If disease responds inadequately to NSAIDs/different bDMARDs
Recommend bDMARD: secukinumab (if within marketing authorisations).
AS management:assessing pharm. treatments
Measuring and evaluating disease activity in AS (and SpA in general) pre- and post-pharmacological treatment is assessed by:
Bath Ankylosing Spondylitis Disease Activity Index (BASDAI):
Scale from 1-10 (1=no problem, 10=worst problem); person answers 6 questions related to the 5 major AS symptoms:
Fatigue.
Spinal pain.
Joint pain/swelling.
Areas of localized tenderness (i.e. enthesitis: inflammation of tendons/ligaments).
Morning stiffness duration.
Morning stiffness severity.
and, Spinal pain visual analogue scale (VAS).
NICE: Response to TNF-α inhibitor(s) should be assessed 12 weeks after the start of treatment. Continue if there is clear evidence of response:
Reduction in BASDAI score to 50% of pre-treatment value, or by 2 or more units and,
Reduction in VAS by 2 cm or more.
Diclofenac sodium
drug class
mechanism
indication
cautions/ contradictions
Drug class: Non-steroidal anti-inflammatory drug (NSAID).
Mechanism of action: non-selective cyclooxygenase (COX)-2 inhibitor; inhibits COX enzymes leading to inhibition of prostaglandin synthesis and anti-inflammatory actions.
Indication and dose: pain and inflammation in rheumatic disease and other musculoskeletal disorders, by mouth: 75mg-150mg daily in divided doses, (modified release for AS).
Cautions and contra-indications:
Lowest effective dose; reviewed regularly.
150mg daily dose increases risk of thrombotic events.
Maximum dose in UK is 150mg regardless of route or indication.
Combined use of aspirin and NSAIDs increase risk of GI damage.
Contra-indicated in ischaemic heart disease, cerebrovascular disease, peripheral artery disease and mild to severe heart failure.
What is Psoriatic arthritis (pSa
A peripheral spondyloarthritis which occurs in <15% of patients with psoriasis .
Affects men and women to similar degree (genetic marker HLA-B27 is frequently positive).
<80% with PsA have asymmetrical arthritis affecting small joints of hand, feet, etc (X-ray/MRI to confirm diagnosis):
Pain and swelling in more than one joint; morning stiffness lasting >30min (similar to RA).
Dactylitis: swollen sausage-shaped fingers and toes (in ~50%).
Enthesitis: inflammation at sites where ligaments or tendons attach to bone (~35% of cases; uncommon in RA).
Less common types of PSA include:
A rheumatoid-like symmetrical seronegative polyarthritis which is rheumatoid factor (RF) negative, Note: ~20% of RA patients are RF-ve.
Arthritis mutilans (<5% of cases): severe form causing pain and destruction of small bones in hands & feet.
pSa: treatment
Non-progressive monoarthritis (arthritis involving one joint at a time): consider as monotherapy local corticosteroid injections.
Offer cDMARDs (take into account patient preference, co-morbidities, if pregnant, etc):
If max dose for 3 months and have no symptomatic relief: consider switching to, or combining with another (standard) cDMARD.
Consider oral NSAIDs as an adjunct to cDMARDs or bDMARDs to manage symptoms:
NSAIDs at lowest effective dose for shortest possible period of time.
Consider GI protective treatment.
If no symptomatic relief with NSAIDs, consider steroid injections (local or IM), or short-term oral steroid therapy as an adjunct to cDMARDs or bDMARDs to manage symptoms.
Leflunomide
Licensed for active PsA (as well as RA): specialist use only.
Potent inhibitor of pyrimidine synthesis that affects T cell proliferation and, thus, is immunomodulatory.
Active metabolite of leflunomide persists for a long time: can be a concern if serious adverse effects are experienced (recommend washout procedure).
Severe adverse effects include bone marrow toxicity, life-threatening hepatotoxicity, infection and malignancy.
Pregnancy must be excluded before treatment and effective contraception must be used during, and for at least 2 years after treatment in women; or 3 months in men (active metabolite is teratogenic inanimalstudies).
Patients must be monitored; Blood counts and liver function.
Other side effects: GI disturbance, hypertension, headache, dizziness, eczema, dry skin, rash.
what is Reactive arthritis
Form of inflammatory arthritis (peripheral SpA), occurs following infection:
Gastrointestinal infection (Shigella, Salmonella, Campylobacter etc).
Sexually-acquired (genitourinary) infection (i.e. Chlamydia).
Believed that persistent bacterial antigens in inflamed (but sterile) synovium of affected joints drive inflammation reaction.
Presents as acute arthritis (knees, ankles, feet) occurring within 4 weeks of an enteric or venereal infection; skin lesions resembling psoriasis.
Treat infections with antibiotics (after initial treatment do not offer this long-term, i.e. 4 weeks+). NSAIDs (ibuprofen) to reduce inflammation; for pain relief.
Acute condition resolves within a few months, but 50% patients go on to develop recurrent arthritis.
For treatment of severe and/or chronic condition consider corticosteroid or cDMARDs (i.e. sulfasalazine) treatment.
what os Enteropathic arthritis
Arthritis (peripheral SpA) linked to inflammatory bowel disease:
10-15% patients with ulcerative colitis or Crohn’s disease have arthritis.
Chronic inflammatory arthritis, commonly affects peripheral (limb) joints and spine.
Arthritis often parallels activity of the bowel condition, improving as bowel symptoms improve.
Very difficult to treat/manage (revisit peripheral SpA drug treatment):
NSAIDs (first-line) improve joint pain but aggravate bowel condition.
