Rheumatology: Antibody --> Condition

Question 1

ANA

Answer 1

SLE
SSc (Systemic sclerosis)
Sjogren
MCTD (mixed connective tissue disorder)

Question 2

Anti-DsDNA

Answer 2

SLE (50-60% sensitive, 95% specific)

Can associate with degree of disease activity

Question 3

Anti-Smith

Answer 3

SLE (30% sensitive, 99% specific)

Not used to associate disease activity level

Question 4

Anti-U1-RNP

Answer 4

MCTD (highly sensitive)

SLE

Question 5

Anti-Ro/SSA

Anti-La/SSB

Answer 5

Sjogren (70% sensitive)
SLE (20% sensitive)
RA
SSc

Question 6

Anti-ribosomal P

Answer 6

SLE (15% sensitive)

Question 7

Anti-Scl-70 (antitopoisomerase-1)

Answer 7

Diffuse cutaneous systemic sclerosis (10-30% sensitive)

Question 8

Anti-centromere

Answer 8

Limited cutaneous systemic sclerosis (CREST)

10-30% sensitive

Question 9

c-ANCA (antiproteinase-3)

Answer 9

Granulomatosis with polyangiitis (Wegener’s)

90% sensitive when dz active, high specificity in clasic presentations

Question 10

p-ANCA (anti-myeloperoxidase)

Answer 10

Microscopic polyangiitis (MPA: 80% sensitive)
Eosinophilic granulomatosis w/ polyangiitis (Churg-Strauss) (EGPA: 60% sensitive, less specific  than c-ANCA)

Question 11

Anti-Jo-1

Answer 11

Polymyositis (20-30% sensitive)

Question 12

RF

Answer 12

RA (70% sensitive, limited specificity especially in pt’s w/out classic dz presentation)
Sjogren
Cryoglobulinemia

Question 13

Anti-cyclic citrullinated peptide (Anti-CCP)

Answer 13

RA (70% sensitive, 95% specific)

Question 14

Anti-histone

Answer 14

Drug-induced Lupus erythematosus (95% sensitive, poor specificity)

Question 15

Cryoglobulins

Answer 15

Vasculitis (type II or III cryoglobulins)
Hep C
Myeloma
SLE
RA