Autoantibodies

Question 1

Antinuclear Antibodies (ANA)

Answer 1

SLE, sensitive, not specific

Question 2

Anti-dsDNA, anti-Smith

Answer 2

SLE, specific

Question 3

Antihistone

Answer 3

Drug-induced Lupus

Hydralazine, procainamide, Isoniazid

Question 4

RF, anti-CCP

Answer 4

Rheumatoid Arthritis

RF = IgM antibody against Fc portion of IgG

Question 5

Anti-centromere

Answer 5

CREST - Scleroderma

C - Calcinosis, Anti-Centromere
R - Raynoud's
E - Esophageal Dysmotility
S - Sclerodactyly
T - Telengiectasis

Usually spares kidneys - classified as “Limited” type

Question 6

Anti-Scl 70 (DNA Topoisomerase I)

Answer 6

Scleroderma (diffuse) - exhibits early visceral involvement (e.g. kidney, heart, lungs, GI tract, etc.)

Question 7

Anti-mitochondrial

Answer 7

Primary biliary cirrhosis

Question 8

IgA antiendomysial, IgA anti-tissue transglutaminase

Answer 8

Celiac’s disease

Question 9

Anti-basement membrane

Answer 9

Goodpasture’s disease

Antibodies against alpha-3 chain of collagen Type IV common to alveolar and GBMs (Type II HS)

Question 10

Anti-desmoglein

Answer 10

Pemphigus Vulgaris
IgG antibody against DSG 3 >> DSG 1
IgG "fist net" appearance; tombstoning at basal surface 
Type II HS
\+ Nikolsky's sign

Question 11

Antimicrosomal, antithyroglobulin

Answer 11

Hashimoto’s disease (sign of damage, these Ab do not necessarily mediate the disease process)

Question 12

Anti-Jo-1, Anti-SRP, anti-Mi-2

Answer 12

Polymyositis, Dermatomyositis

Question 13

Anti-SSA (anti-Ro)

Answer 13

Sjogren’s Syndrome

Question 14

Anti-SSB (anti-La)

Answer 14

Sjogren’s Syndrome

Question 15

Anti-U1 RNP (Ribonucleoprotein)

Answer 15

MCTD

Question 16

Anti-smooth muscle

Answer 16

Autoimmune hepatitis

Question 17

Anti-glutamate decarboxylase

Answer 17

T1DM

Question 18

c-ANCA (PR3-ANCA)

Answer 18

Granulomatosis with polyangiitis (Wegener’s)

Question 19

p-ANCA (MPO-ANCA)

Answer 19

Microscopic polyangiitis, Churg-Strauss syndrome