Histo: Connective tissue diseases (Phyllis' Version)

Question 1

What is SLE?

Answer 1

Autoimmune multi-system disorder

Type III hypersensitivity reaction (immune complexes)

↑ in classical complement deficiencies

Can be drug- induced

↑in AfroC. F>M

Question 2

HLA association for SLE

Answer 2

HLA DR3 or DR2

Question 3

Autoantibody for SLE + which is most specific + which for drug induced SLE

Answer 3

ANA (95%)
Anti dsDNA
Anti-Sm (most specific)
Anti-histone (drug induced)

Question 4

Mnemonic for SLE symptoms?

Answer 4

SOAP BRAIN MD

Serositis
Oral ulcers
Arthritis

Photosensitivity Blood disorders (AIHA, ITP, leucopenia)
Renal involvement ANA +ve
Immune phenomena (dsDNA, anti-Sm, Antiphospholipid Ab)
Neuro symptoms Malar rash Discoid rash

Question 5

Histology of SLE?

Answer 5

LE bodies
Kidney – “wire- loop” appearance of glomeruli [BUZZWORD] CNS – small vessel angiopathy
Spleen – “onion skin” lesions
Heart – Libman- Sack Endocarditis

Question 6

What is scleroderma?

Answer 6

Either limited (CREST) or diffuse

Autoimmune multi-system disorders characterised by widespread vasculopathy and fibrosis of skin and internal organs due to excess collagen deposition
Scleroderma literally means “hard skin” - reflecting the main clinical feature of skin fibrosis

Question 7

HLA association for scleroderma

Answer 7

HLA DR5 or DRw8

Question 8

Autoantibody for limited scleroderma vs diffuse

Answer 8

Anticentromere - limited
Anti-topoisomerase II (Scl-70) - diffuse

Question 9

Symptoms/signs of diffuse scleroderma

Answer 9

Skin changes can occur anywhere (Distal and proximal)

Tendon friction Reynauld’s phenomenon

Widespread organ involvement, early heart, GI and renal disease

Associated with pulmonary fibrosis

Question 10

Symptoms/signs of limited scleroderma

Answer 10

Distal skin
involvement ONLY

CREST:
Calcinosis Raynaud’s
Esophageal dysmotility Sclerodactyly Telangiectasia

RARE renal and heart disease
Associated with pulmonary hypertension at very old age

Question 11

Histology of limited vs diffuse scleroderma?

Answer 11

Limited - ↑collagen in skin and organs. “Onion skin” thickening of arterioles [BUZZWORD]

Diffuse - Inflammation within or around muscle fibres

Question 12

What is polymyositis or dermatomyositis?

Answer 12

Skeletal muscle disorders characterised by progressive muscle weakness and inflammation on muscle biopsy

Question 13

definitive Ix for myositis?

Answer 13

muscle biopsy

Question 14

What is poly/dermatomyositis associated with?

Answer 14

underlying malignancy -
DM → ovarian, pancreatic, NHL
PM → lung, bladder, NHL

Question 15

Autoantibodies for poly/dermatomyositis? + other blood tests or Ix

Answer 15

Anti Jo-1

increased CK/LDH/myoglobin and abnormal EMG

Question 16

signs/symptoms for poly/dermatomyositis?

Answer 16

Proximal muscle weakness → difficulty performing gross motor tasks (e.g. getting up from a chair, climbing steps, combing hair etc)

DM has cutaneous features:
(1) Heliotrope rash with
eyelid oedema
(2) Gottron papules
(erythema of knuckles w/ raised scaly eruption)
(3) Systemic V-shaped rash
(4) Facial rash
Associated w. pulmonary fibrosis