Rheumatoid Arthritis

Question 1

What are some sources of musculoskeletal pain?

Answer 1

Soft tissue, bone, joint, referred central pain

Question 2

How can rheumatic disorders be classified?

Answer 2

Inflammatory -> autoimmune/crystal arthropathy/infection

Degenerative -> osteoarthritis

Question 3

What are some causes of inflammatory polyarthritis?

Answer 3

Infection eg streptococcal septic arthritis
Crystal arthritis eg gout
Rheumatoid
Systemic lupus erythematous
Post infective arthritis (reactive arthritis)
Sarcoidosis

Question 4

Why does the prevalence of autoantibodies increase as we age?

Answer 4

Repeated exposure of infection leads to production of autoantibodies

Question 5

What are some theories of autoimmunity?

Answer 5

Defects in regulatory T cells (some recognise self-peptides and mature to leave thymus)
Molecular mimicry between pathogens and self-peptides
Polyclonal activation of B cells during immune response = recognition of self-antigens

Question 6

What class of genes are autoimmune diseases strongly associated with?

Answer 6

HLA - suggesting presentation of self-peptides to auto reactive T cells

RA - HLA-DR4 or HLA-DR1

Question 7

What are the 3 most common autoimmune diseases?

Answer 7

Grave’s disease, Rheumatoid arthritis, Hashimotos thyroiditis (all much more common in females)

Question 8

What’s a typical presentation/history of RA?

Answer 8

Female, 20-50 years old
Pain and stiffness in small joints
Symmetrical
Gradual or sudden onset
Often family member has RA
Smoking history (increases risk)

Question 9

Other than joint problems, what are other symptoms of RA?

Answer 9

Fatigue, anorexia, weight loss
Low grade fever, anaemia
Extra-articular features in skin, eyes, resp, cardio

Question 10

What signs can be seen on a hand examination in RA?

Answer 10

Early fusiform swelling
Ulnar deviation / MCP subluxation
Swan neck deformities
Boutoniere deformities

Question 11

What are extra-articular features of RA?

Answer 11

Cardiac: pericarditis, valve problems, atherosclerosis
Pulmonary: pleural effusions, rheumatoid nodules, pulmonary fibrosis
Blood: anaemia, splenomegaly
Bones: localised osteoporosis
Skin: rheumatoid nodules, leg ulcers
Neurological: C1/C2 subluxation, nerve compression
Eyes: scleritis, xerophthalmia

Question 12

Why is it important to address risk factors like smoking in RA patients?

Answer 12

Increased risk of ischaemic heart disease: address smoking, raised cholesterol, obesity

Question 13

What’s the pathophysiology of rheumatoid arthritis?

Answer 13

T-cell mediates immune response (by genetic predisposition + trigger)
RF antigen forms complex with IgG = complement fixation
Inflammatory response: angiogenesis and inflammatory cell recruitment
Enzymes and prostaglandins released
Synovial proliferation and pannus invasion
= articular cartilage and underlying bone destroyed

Question 14

What’s the primary and secondary cause of damage to the joint in RA?

Answer 14

Primary - synovium inflammation

Secondary - cartilage destruction

Question 15

What are the investigations of RA?

Answer 15

FBC (look for anaemia)
ESR/CRP should be moderately raised
Immunology: raised RF and anti-CCP

Raised Alkaline Phosphatase, reduced Albumin

Question 16

What will radiological investigations in RA show?

Answer 16

X-rays normal in early disease but synovitis can be detected on ultrasound/MRI

X-ray of hands or feet in developed disease:
soft tissue swelling
junta-articular osteopenia
joint space narrowing
erosions
subluxation
deformity

Question 17

What’re the pharmacological treatments for RA?

Answer 17

Pain relief: paracetamol -> paracetamol + NSAID -> weak opioid -> strong opioid

Corticosteroids
DMARDs: Methotrexate / Azathioprine / Sulfasalazine
Biologic agents: Infliximab / Rituximab

Important to monitor reduced immunity from immunosuppressants