Rheum- RA Flashcards
Risk Factors for RA?
Female sex
Age 50-55
Genetic Predisposition
Smoking
What is the pathogenesis for RA?
Citrullination of self antigens
Causes T & B cells to produce antibodies against them
What is the pathogenesis for joint swelling RA?
TNFa released by fibroblasts and macrophages
cause the inflammatory cascade leading to proliferation of synoviocytes - produce synovial fluid- causing swelling
What is the pathogenesis for bone damage in RA?
Restriction of nutrients due to joint swelling
Macrophages stimulate osteoclast differentiation causing bone damage
What is the pattern of arthralgia in RA?
Peripheral, symmetrical polyarthritis
What are the most common joints affected in RA?
MCPs (metacarpophalangeal) /PIPs (Proximal Interphalangeal) /MTPs (Metatarsophalangeal)
Which joints are typically spared in RA?
DIPs (distal interphalangeal)
hat is the diagnosis history criteria for RA?
Hx >6 weeks
Morning stiffness >30 mins
Other symptoms: fatigue/malaise
What signs may be seen on examination of RA?
Soft tissue swelling/tenderness Ulnar deviation of MCPs Palmar subluxation of MCPs Swan neck deformity Boutonniere's deformity Z-deformity of thumb Rheumatoid nodules on joints (elbow) Median nerve involvement (carpal tunnel)
What’s the pathology of swan neck deformity?
PIP hyperextension
DIP flexion
What antibodies would you check for in RA?
Anti-CCP (citrullinated cyclic peptide)
Rheumatoid Factor
What blood test would you order and why for ?Ra?
FBC anaemia of chronic disease WCC- septic arthritis Platelets- increased due to inflammation Inflammatory markers (CRP/ESR) : raised
What imaging would you order for RA?
X-ray
USS/MRI: more sensitive in early disease
CXR/ pulmonary function tests : if history indicative of chest involvement
What type of anaemia is anaemia of chronic disease?
Normocytic
What would you see on an X-ray for RA?
Loss of joint space
Erosions- periarticular
Soft tissue swelling
Subluxation- incomplete or partial dislocation of joint
