rheumatoid arthritis Flashcards
what is it?
inflammatory autoimmune disorder characterised by symmetrical joint pain, swelling and synovial destruction
what is the pathophysiology?
synovium becomes inflamed and invasive; inflammatory mediators eats away into articular cartilage and bone
what type of hypersensitivity reaction is it driven by?
4
what are the markers for it and what one is more sensitive?
rheumatoid factor and anti-CCP
what is rheumatoid factor?
IgM or IgA binds to Fc region of IgG
what does anti-CCP correlate with?
disease activity anf levels remain positive despite treatment
how does it clinically present?
pain
swelling
loss of mobility
what are characteristics of it?
symmetrical pain
most commonly affects PIPs/MCPs and MTPs
early morning stiffness >30min -> improves with activity
what are the joint deformities?
swan neck deformity
boutonniere deformity
what is swan neck deformity?
PIP hyperextension and DIP flexion
what is boutonniere deformity?
PIP flexion and DIP hyperextension
only affects vertebrae at which level?
C1-C2
why does it only affect vertebral level C1-C2?
only joint in spine with synovium
what are the clinical signs?
swelling of affected joints
positive compression test of MCP and MTP
bouchards nodes
cysts
synovitis
what investigations are used?
bloods
x-ray
USS
MRI
what will bloods show?
raised inflammatory markers (CRP, plasma viscosity, ESR)
presence of rheumatoid factor and anti-CCP
what will x-ray show in early disease?
can be normal
may show soft tissue swelling and periarticular disease
what will x-ray show in late disease?
erosions
subluxation
what is USS useful for?
detecting synovial inflammation if clinical uncertainty
useful in making treatment changes
when would you use MRI?
if diagnostic doubt
what score do you need to have on diagnostic criteria to diagnose?
6/10 or more
what is 1st line treatment?
1 DMARD +/- corticosteroid
when should DMARDs start?
within 3 months of symptom onset
what is the preferred DMARD?
methotrexate
