Antibodies

Question 1

Extractable Nuclear Antigens

Answer 1

Anti-RNP
Anti-centromere antibody 
Anti-Scl-70
Anti-Ro and anti-LA
Anti-Jo-1
Anti-Sm
ACLA antibodies

Question 2

Anti-RNP

Answer 2

Usually positive in mixed connective tissue disease

May be positive in SLE

Question 3

Anti-centromere antibody

Answer 3

Usually positive in limited systemic sclerosis

Question 4

Anti-Scl-70

Answer 4

Often positive in diffuse systemic sclerosis

Question 5

Anti-Ro and Anti-La

Answer 5

Usually positive in primary Sjogren’s syndrome

Question 6

Anti-Jo-1

Answer 6

May be present in inflammatory myositis

Question 7

Anti-Sm

Answer 7

Very specific for SLE

Question 8

ACLA antibodies

Answer 8

Positive in anti-phospholipid syndrome

Question 9

ACLA antibodies increase the risk

Answer 9

Pregnancy loss

Thrombosis

Question 10

Anti-dsDNA

Answer 10

Used in SLE

Changes with disease activity

Question 11

Anti-nuclear antibody

Answer 11

Very non-specific
Good negative test to rule out SLE
Positive in a wide range of connective tissue diseases

Question 12

Anti-CCP antibody

Answer 12

Very specific in rheumatoid arthritis

Can be negative in RA

Question 13

Rheumatoid Factor

Answer 13

Can be useful for rheumatoid

Presence doesn’t confirm, quite non-specific

Question 14

Anti-neutrophil cytoplasmic antibodies

Answer 14

c-ANCA
p-ANCA
C3/4

Question 15

c-ANCA/anti-PR3

Answer 15

Very sensitive for Granulomatosis with Polyangitis

Question 16

p-ANCA/anti-MPO

Answer 16

Associated with
Microscopic polyangitis
Churg Strauss syndrome
Less specific

Question 17

C3/C4

Answer 17

Low in immune complex vasculitis especially lupus nephritis