Rheumatoid Arthritis

Question 1

what is rheumatoid arthritis?

Answer 1

Chronic autoimmune disease characterised by pain, stiffness and symmetrical synovitis (inflammation of the synovial membrane) of synovial (diarthrodial) joints

Question 2

what are some key features of chronic arthritis?

Answer 2

Polyarthritis - swelling of the small joints of the hand and wrists is common

Symmetrical

Early morning stiffness in and around joints

May lead to joint damage and destruction - ‘joint erosions’ on radiographs

Question 3

describe the immunology of rheumatoid arthritis

Answer 3

autoimmune response to an antibody

IgM autoantibodies recognise the Fc portion IgG as their target antigen

Question 4

which joints are affected in RA?

Answer 4

Metacarpophalangeal joints (MCP)
Proximal interphalangeal joints (PIP)
Wrists 
Knees
Ankles
Metatarsophalangeal joints (MTP)

early generally just in hands and feet

Question 5

what is Boutonniere deformity?

Answer 5

hyper flexion at the proximal interphalangeal joint

Question 6

what is swan neck deformity?

Answer 6

hyper extension at PIP joint and hyper flexion at distal interphalangeal joint

Question 7

how can smoking increase chance of developing rheumatoid arthritis

Answer 7

smokers- chronic airway autoimmune
triggers citrullination
antibodies to citrullinated peptides are highly specific for rheumatoid arthritis

Question 8

what are other features of RA not to do with the joints?

Answer 8

Common:
Fever, weight loss
Subcutaneous nodules

Uncommon:
vasculitis
Ocular inflammation e.g. episcleritis
Neuropathies
Amyloidosis
Lung disease – nodules, fibrosis, pleuritis
Felty’s syndrome – triad of splenomegaly, leukopenia and rheumatoid arthritis

Question 9

what are the stages of radiographic abnormalities?

Answer 9

Early
Juxta-articular osteopenia (bone thinning)

Later
Joint erosions at margins of the joint

Later still
Joint deformity and destruction

Question 10

what is the pathophysiology of RA?

Answer 10

synovial membrane abnormal 
synovium becomes proliferated due to neovascularisation,
lymphangiogenesis and
inflammatory cells
-activated B and T cells
-plasma cells
-mast cells
-activated macrophages

Recruitment, activation and effector functions of these cells is controlled by a cytokine network
there is an excess of pro-inflammatory vs. anti-inflammatory cytokines (‘cytokine imbalance’)

Question 11

how do you treat RA?

Answer 11

treat early and aggressively

interleukin-6 and interleukin-1 blockade now available in clinic

deplete B cells in rheumatoid arthritis by parenteral (intravenous) administration of an antibody against a B cell surface antigen, CD20

physiotherapy

surgery

DMARDS (disease- modifying anti-rheumatic drugs)

glucocorticoid therapy (avoid long term use)

Question 12

give an example of a DMARD drug and give a side effect of this drug

Answer 12

methotrexate

upset the liver