Rheumatoid Arthritis Flashcards
what is rheumatoid arthritis
inflammatory joint disease affecting joints with synovium in them
affects any age group
what joints aren’t affected by rheumatoid arthritis and why
distal interphalangeal joints (DIP) as they dont have much synovium
are men/women more likely to be affected
women (3x more likely)
what happens when rheumatoid arthritis is left untreated
can lead to joint damage and irreversible deformities leading to loss of function
what causes rheumatoid arthritis
Can be genetic
potential triggers: infections, stress, smoking
depends on genetic factors and the presence of autoantibodies
HLA-DR4 mediated (MHC2 receptor)
what is the synovium
tissue inside the synovial joint capsule and tendon sheath.
makes direct contact with synovial fluid and acts as a joint lubricant.
signs of rheumatoid arthritis
swollen inflamed synovial membrane leading to bone erosion
what happens to the synovium in RA
swollen an inflamed > mass of spongy tissue>increased blood flow>more inflammation cells one osteoclasts>osteoclasts dissolve the bone
What is pannus
hypervasculated swollen, inflamed synovium
describe the pathogenesis of RA
unknown antigen presented to T cells> T cells activated>stimulated B cells and mactophages>macrophages releases cytokines and B cells release antibodies
This all leads to increased osteocyte stimulation leading to joint destruction
when is the window of opportunity where the disease can be modified
first 3 months
typical RA history
history - recent (short history) pain in the synovial joints, early morning stiffness that improves throughout the day
what investigations do you do for RA
blood test for inflammatory markers, (normocytic) anaemia, raised platlets
autoantibodies
imaging
Clinical examination findings in RA
bilateral, symmetrical swelling
difficulty forming fists
tenderness in joint
criteria for RA
morning stiffness arthritis of 3 or more joint areas arthritis of hand joints symmetric arthritis rheumatoid nodules serum rheumatoid factor
what is seen on an X ray
normal in early stages, changes only seen later when there is synovium swelling
what is the squeeze test for
squeeze hands/feet gentle and if there is pain there is synovitis
what is tenosyvonitis
swelling of the tendons, RA can present as this
what is trigger finger
finger stuck in a flex position and straightens out with a click, can be a sign of RA
possible clinical presentations of RA
tenosyvonitis trigger finger carpal tunnel polymalalgia rheumatic palindromic rheumatism (comes and goes) systemic symptoms poor grip strength
what does extensor tenosynovisits look like
swelling on the back of the hand - wrist stays okay
must treat otherwise tendons fray and tear so patients cant extent their fingers anymore
DIP normal
typical presentation of RA
DIP joints spared and synovium joints inflamed
What autoantibodies are seen in RA
Rheumatoid factor
Anti-CCP antibodies (more specific)
some people with rheumatoid arthritis have no antibodies at all
what is seen on Xray in RA
soft tissue swelling
erosions
inflammed synovium
periarticular osteopenia
no findings in early disease
Ultrasound scans in RA
increases sensitivity for early disease
constantly superior to clinical exam
can detect up to 7 times more MCP erosions than plain x ray in early RA
useful in making treatment changes
MRI scans
bone marrow oedema on MRI associated with inflammatory joint disease and a forerunner of erosion
integrity of tendons can be assent
can distinguish synovitis from effusions
can detect erosion early
can monitor disease activity
limited by cost
what is DAS 28
score of joint disease severity
lower DAS less likely joint will be damage, aim for <2.6
Management
early recognition and diagnosis care by rheumatologist early treatment with disease modifying anti-rheumatic drugs NSAIDS and steroids Patient education multidisciplinary team involvement
what are some disease modifying anti-rheumatic drugs (DMARDS)
methotrexate sulfasalazine hydrochloroquine combination with MTX,SASP and HCQ leflunomide penicillamine axathiprime
what do DMARDS do
suppress bone marrow
what are biologic agents
Anti-TNF agents T cell receptor blockers B cell receptor blockers IL6 blocker JAK2 inhibitor
(inhibit various parts of the immune pathway)
common side effect of biological agent
infections
complications of non-treated rheumatoid arthritis
deformity of thumb
ulnar deviation of metacarpophalangeal joints
swan neck deformity of fingers
