Joint Pathology

Question 1

What type of collagen does articular cartilage contain?

Answer 1

II

Question 1

At what time during the day is the pain of OA at its worse?

Answer 1

At hte end of the day, after prolonged use

Question 2

What other body systems can be affected by RA?

Answer 2

Skin

Blood vessels

Heart

Lungs

Question 3

What might you observe in OA joints?

Answer 3

Reduced ROM

Crepitus (grinding)

Osteophytes

Question 4

What is fibrillation of cartilage?

Answer 4

Where the surface of cartilage has a shredded appearance due to damage

Question 5

Describe the pathogenesis of OA?

Answer 5

There is some injury to the joint stimulating chondrocyte proliferation, enzyme/cytokine activity and matrix depletion >

The cartilage matrix begins to unravel with release of enzymes and collagenases and loss of mechanical function >

Thickening of bone and microfractures >

Shredding of cartilage > Fibrillations and erosion >

Bone on bone > erosion, cysts, osteophytes

Question 5

When in the day are joint symptoms of RA the worse?

Answer 5

Morning > they ease off with activity

Question 6

What are the immune mediators of RA?

Answer 6

Th-1 and Th-17

• IL-1, IL-6, IL-17, TNFalpha

B cells (plasma cells)

Macrophages

Question 7

Does too much uric acid always present as gout?

Answer 7

No, it’s asymptomatic at first; for up to 20-30 years

Question 7

Why isn’t serum urate a good diagnostic for gout?

Answer 7

It is lower during attacks due to urate precipitating

Urate-lowering therapy can precipitating gout

Must people with high urate don’t have gout

Question 8

What are some systemic signs of RA?

Answer 8

Fever

Anaemia

Weight loss

Question 9

What do you see histologically in RA?

Answer 9

Mononuclear cell infiltration

Villous hyperplasia

Germinal centres

Question 10

What is tophaceous gout?

Answer 10

The chronic form of gout with involvement of

• Multiple joints
• Recurrent joint inflammation causing damage
• Urate deposition as tophi
• Gouty nephropathy and kidney stones

Question 11

What is podagra?

Answer 11

Gout in the big toe

Question 12

What is the gold standard for gout diagnosis?

Answer 12

Joint aspirate of crystals with neutrophils

Question 13

Describe the appearance/texture of RA joints?

Answer 13

Doughy

Question 15

How do you diagnose RA?

Answer 15

CRP, ESR, FBE for inflammation

Rheumatoid factor

Anti-cyclic citrullinated peptide (anti-CCP)

Question 16

What is the pathological process that leads to RA?

Answer 16

Inflammatory response against arthritogenic antigen >

Mononuclear cells infiltration with germinal centres >

Hyperplasia of synovial membrane > villous formation >

Pannus formation (granulation tissue) >

Neutrophil and fibrin may enter >

Pannus invades and erodes bone and cartilage >

Weakening of ligaments >

Union of bone

Question 17

How do RA joints appear on x-rays at the end stage of the disease?

Answer 17

Subchondral erosion

Uniform joint space loss

Question 18

What are the symptoms of gout?

Answer 18

Spontaneous onset of excruciating pain, heat, redness and swelling

Question 19

What must occur at the joint for perfusion of articular cartilage to occur?

Answer 19

Compression and decompression of the cartilage

Question 20

Which joint pathology has punched out overhanging edges?

Answer 20

Gout

Question 21

What do subchondral cysts contain?

Answer 21

Synovial fluid

Question 22

How do tophi appear histologically?

Answer 22

Granulomatous inflammation (foreign body type)

• Epithelioid macrophages
• Multi-nucleated giant cells
• Central urate crystal deposites

Question 24

What are the types of cells that make up the synovial membrane?

Answer 24

Type A - Macrophage like

Type B - Fibroblast like

Question 25

What are the three histological features of OA?

Answer 25

Subchondral thickening

Osteophytes

Non-uniform loss of cartilage

Question 26

Why do you get neutrophil lysis with gout?

Answer 26

Urate cystals pierce the neutrophil membrane

Question 27

What is added to synovial fluid to increase its lubricating ability?

Answer 27

Hyaluronic acid

Question 29

How much do genetics contribute to risk of developing RA?

Answer 29

50%

Question 30

How do rheumatoid nodules appear histologically?

Answer 30

Granulomatous inflammation

• Central necrosis
• Epithelioid macrophages
• Lymphocytes and fibroblasts surrounding