Antibodies

Question 1

Thyroid peroxidase Ab?

Answer 1

• Hashimoto’s thyroiditis (87%)
• Grave’s (50%)

Question 2

Anti-RNP?

Answer 2

• SLE
• Mixed connective tissue disease

Question 3

Perinuclear antineutrophil cytoplasmic Ab (pANCA)?

Answer 3

• Microscopic polyangiitis (45%)
• Churg-Strauss
• Pulmonary-renal vasculitides (Goodpasture’s)

Question 4

Anti-La (SSB)?

Answer 4

• Sjogren’s syndrome
• SLE (15%)

Usually ANA +ve

Question 5

Other things ANCA can be +ve in?

Answer 5

• UC/Crohn’s
• Sclerosing cholangitis
• Autoimmune hepatitis
• Felty’s syndrome
• RA
• SLE
• Drugs (antithyroid, allopurinol, ciprofloxacin)

Question 6

Anticentromere Ab?

Answer 6

Limited systemic sclerosis

Question 7

Anti Jo-1, Anti-Mi-2?

Answer 7

Polymyositis = chronic inflammation of the muscles (inflammatory myopathy) related to dermatomyositis and inclusion body myositis

Dermatomyositis - purple heliotrope rash (eyes)

PARANEOPLASTIC SYNDROMES

Question 8

Cytoplasmic antineutrophil cytoplasmic Ab (cANCA)?

Answer 8

• Granulomatosis with polyangiitis (Wegener’s) - 90%
• Microscopic polyangiitis (30%)
• Polyarteritis nodosa (11%)

Question 9

Anti-double-stranded DNA (dsDNA)?

Answer 9

SLE (60% sensitivity, but highly specific)

Question 10

Anti-Scl70?

Answer 10

Diffuse systemic sclerosis

Question 11

RhF?

Answer 11

• Sjogren’s syndrome (100%)
• Felty’s Syndrome (100%)
• RA (70%)
• Mixed connective tissue disease (50%)
• SLE (40%)
• Systemic Sclerosis (30%)

Question 12

Antiphospholipid Ab? (e.g. anti-cardilolipin Ab)

Answer 12

• Antiphospholipid Syndrome
• SLE

Question 13

Intrinsic factor Ab?

Answer 13

Pernicious anaemia (50%)

Question 14

a-gliadin Ab Antitissue Transglutaminase IgA

Anti-endomysial Ab

Answer 14

Coeliac disease

Question 15

Anti-voltage-gated Ca2+ channel Ab?

Answer 15

Lambert-Eaton syndrome

Question 16

Anti-Sm?

Answer 16

SLE (20-30%)

Question 17

Glomerular basement membrane Ab (anti-GBM)?

Answer 17

Goodpasture’s disease (100%)

Question 18

Antimitochondrial Ab (AMA)?

Answer 18

• Primary biliary cholangitis (95%)
• Autoimmune hepatitis (30%)
• Idiopathic cirrhosis (25-30%)

Question 19

Anti-voltage-gated K+ channel Ab?

Answer 19

Limbic encephalitis

Question 20

Anti-Ro (SSA)?

Answer 20

• SLE
• Sjogren’s syndrome
• Systemic sclerosis
• Associated with congenital heart block

Usually with ANA +ve

Question 21

Acetylcholine receptor Ab?

Answer 21

Myasthenia gravis (90%)

Question 22

Gastric parietal cell Ab?

Answer 22

• Pernicious anaemia (90%)
• Atrophic gastritis (40%)

Question 23

Antinuclear antibody (ANA)?

Answer 23

• SLE (95%)
• Systemic sclerosis (96%)
• Autoimmune hepatitis (75%)
• Sjogren’s syndrome (68%)
• RA (30%)

Question 24

Patterns of ANA staining?

Answer 24

• Homogenous = SLE
• Speckled = mixed CT disease
• Nucleolar = Sytemic sclerosis
• Centromere = limited systemic sclerosis

Question 25

Islet cell Ab (ICA)

Glutamic acid decarboxylase Ab (GAD)

Answer 25

TIDM (75%)

Question 26

Anti-smooth muscle Ab (SMA)?

Answer 26

• Autoimmune hepatitis (70%)
• Primary biliary cholangitis (50%)
• Idiopathic cirrhosis (25-30%)

Question 27

Anticyclic citrullinated peptide Ab (anti-CCP)?

Answer 27

RA (96% specificity)

Question 28

Antihistone Ab?

Answer 28

Drug induced SLE (100%)