Histopathology - Connective Tissue Diseases

Question 1

What are the HLA associations for SLE?

Answer 1

HLA DR3 (or 2)

Question 2

What are the HLA associations for CREST Syndrome?

Answer 2

HLA DR5 + DRw8

Question 3

What are the HLA associations for Diffuse scleroderma?

Answer 3

HLA DR5 + DRw8

Question 4

What are the general features of SLE?

Answer 4

• Autoimmune multi-system disorder
• Type III Hypersensitivity reaction
• Increase in classical complement deficiencies
• Can be drug-induced
• Increase in Afro C
• F>M

Question 5

What auto-antibodies are associated with SLE?

Answer 5

ANA (95%)
- Anti-dsDNA
- Anti-Sm
- Anti-Smith (most specific)
- Anti-histone (+ve if drug-induced SLE)

Question 6

What are the histological findings of SLE?

Answer 6

• LE bodies
• Kidney: “WIRE LOOP” appearance of glomeruli
• CNS: Small vessel angiopathy
• Spleen: “ONION SKIN” lesions
• Heart: Libman-Sack Endocarditis

Question 7

What are the signs + symptoms of SLE?

Answer 7

Need 4/11 ACR criteria
SOAP BRAIN MD
- S: Serositis
- O: Oral ulcers
- A: Arthritis
- P: Photosensitivity
- B: Blood disordrs (AIHA, ITP, Leukopenia)
- R: Renal involvement
- A: ANA +ve
- I: Immune phenomena (dsDNA, anti-Sm, Antiphospholipid Ab)
- N: Neuro Sx
- M: Malar rash
- D: Discoid rash

Question 8

What are the general featuers of CREST syndrome?

Answer 8

• Autoimmune multi-system disorder
• Widespread vasculopathy + fibrosis of skin + internal organs (due to excess collagen deposition)
• Scleroderma = hard skin

Question 9

What auto-antibodies are associated with CREST syndrome?

Answer 9

Anti-centromere

Question 10

What are the histological features of CREST syndrome?

Answer 10

• Increased collagen in skin + organs
• “onion skin” thickening of arterioles

Question 11

What are the Signs + Sx of CREST Syndrome?

Answer 11

DISTAL SKIN involvement only
- C: Calcinosis
- R: Raynaud’s
- E: Esophageal dysmotility
- S: Sclerodactyly
- T: Telangiectasia

RARE renal + heart disease

A/w: Pulmonary HTN at v. old age

Question 12

What are the general features of diffuse scleroderma?

Answer 12

• Autoimmune multi-system disorder
• Widespread vasculopathy + fibrosis of skin + internal organs (due to excess collagen deposition)
• Scleroderma = hard skin

Question 13

What auto-antibodies are associated with diffuse scleroderma?

Answer 13

• Anti-topoisomerase II (Scl-70)

Question 14

What are the histological features of diffuse scleroderma?

Answer 14

• Inflammation within or around muscle fibres

Question 15

What are the signs + Sx of diffuse scleroderma?

Answer 15

• Skin changes occur anywhere (Distal + proximal)
• T: Tendon friction
• R: Raynaud’s phenomenon
• Widespread organ involvement
• Early heart, GI + Renal disease

A/W: Pulmonary fibrosis

Question 16

What are the general features of polymyositis + dermatomyositis?

Answer 16

• Skeletal muscle disorders
• Characterised by progressice muscle weakness + inflammation on muscle biopsy

A/W: underlying malignancy:
- DM: Ovarian, pancreatic, NHL
- PM: Lung, Bladder, NHL

Question 17

What autoantibodies are associated with Polymyositis + Dermatomyositis?

Answer 17

• Anti-Jo-1 (tRNA Synthetase)
• Increased CK/LDH/Myoglobin + abnormal EMG

Question 18

What are the histological features of polymositis?

Answer 18

• Endomysial inflammatory infiltrate

Question 19

What are the histological features of dermatomyositis?

Answer 19

• “DROP OUT” of capillaries
• Myofibre damage

Question 20

What are the signs + Sx of Dermatomyositis + Polymyositis?

Answer 20

• Proximal muscle weakness (difficulty performing motor tasks)
• A/W: Pulmonary fibrosis

DM Features:
- Heliotrope rash with eyelid oedema
- Gottron papules (erythema of knuckles with raised scaly eruption)
- Systemic V-shaped rash
- Facial rash