Rheumatoid Arthritis Flashcards
Define Rheumatoid Arthritis
Chronic autoimmune disease characterised by pain, stiffness and SYMMETIRCAL SYNOVITIS of synovial (diarthrial) joints
When is the stiffness in the joints particularly bad in rheumatoid arthritis and what can make it better?
In the morning
It gets better with exercise
What is a relatively common extra-articular manifestation of rheumatoid arthritis?
Rheumatoid nodules
What causes the extra-articular manifestations?
Rheumatoid factor produces immune complexes that can go anywhere
What type of antibody is the rheumatoid factor?
IgM antibody that binds to the Fc portion of IgG
Is rheumatoid arthritis more common in males or females?
More common in females (3:1)
What is the important genetic component that predisposes toRheumatoid Arthritis?
The genetic component comes down to a specific set of amino acids within the beta chain of the DR molecule (amino acids 70-74 of the DR Beta1-chain)
This set of amino acids is conserved among all HLA subtypes that are associated with rheumatoid arthritis – it is called the shared epitope
What important environmental factor can affect the susceptibility and severity of Rheumatoid Arthritis?
Smoking
State some joints that are commonly affected in Rheumatoid Arthritis.
Metacarpophalangeal joint (MCP) Proximal interphalangeal joint (PIP) Wrists Knees Ankles Metatarsophalangeal joint (MTP)
Name and describe two deformities that are indicative of Rheumatoid Arthritis.
Swan-neck deformity Hyperextension of PIP Hyperflexion of DIP Boutonniere deformity (button-like) Hyperflexion at PIP
What is the term given to fingers that are completely swollen, notjust around the joints?
Dactylitis – this can’t be explained by Rheumatoid Arthritis because it is not just the joints that are inflame
Describe the appearance of extensor tenosynovitis.
There will be swelling around the extensor tendon that is inflamed
When the fingers are extended, the swelling will move showing that the inflammation is around the tendon and not the joint
Other that joints and around tendons, where else can synovium become inflamed?
Bursae –> Bursitis
What are sub-cutaneous nodules?
Central area of fibrinoid necrosis surrounded by histiocytes and a peripheral layer of connective tissue
Why are rheumatoid nodules an important clinical finding?
Patients with rheumatoid nodules are always rheumatoid factor positive
Where are rheumatoid nodules commonly seen?
Along the ulnar border