Autoantibodies

Question 1

autoantibodies PSC

Answer 1

Autoantibodies: No antibodies are highly sensitive or specific to PSC. They aren’t very helpful in diagnosis but they can indicate where there is an autoimmune element to the disease that may respond to immunosuppression.
Antineutrophil cytoplasmic antibody (p-ANCA) in up to 94%
Antinuclear antibodies (ANA) in up to 77%
Anticardiolipin antibodies (aCL) in up to 63%

Question 1

autoantibodies PBC

Answer 1

anti-mitochondrial antibodies (AMA) is most specific to PBC, anti-nuclear antibodies are present in 35% of patients

Question 2

genetic associations rheumatoid arthritis

Answer 2

HLA DR4 (a gene often present in RF positive patients)

HLA DR1 (a gene occasionally present in RA patients)

Question 3

auto-antibodies rheumatoid arthritis

Answer 3

Rheumatoid factor (RF) - positive in 70% of patients

Cyclic citrullinated peptide antibodies (anti-CCP) - more sensitive and specific than rheumatoid factor

Question 4

best autoantibody test for rhuematoid arthritis

Answer 4

Cyclic citrullinated peptide antibodies (anti-CCP) - more sensitive and specific than rheumatoid factor

Question 5

in what % of patients is RF positive

Answer 5

70%

Question 6

auto-antibodies coeliac

Answer 6

anti-ttg = anti- tisue trasglutaminase

anti-ema = anti-endomysial

Question 7

autoantibodies pernicious anaemia

Answer 7

Anti-intrinsic factor antibodies

Anti-parietal cell antibodies (to confirm/refute if anti-intrinsic antibodies negative)

Question 8

autoantibodies assocuated with hashimotos hypothyroid

Answer 8

anti-thyroid peroxidase (anti-TPO) antibodies

and anti-thyroglobulin (anti-Tg) antibodies.

Question 9

what things should you ask about to investigate vasculitis as the cause of mononeuritis multiplex

Answer 9

• kidneys : going for a wee regularly? haematuria?
  check U&Es
• skin: purpura,
• respiratory: cough? sinusitis?

Question 10

autoantibodies SLE

Answer 10

ANA - SENSITIVE - 85-99% will have positive - other things can make it positive. can be used effectively as rule out test

Anti-dsDNA - SPECIFIC 50% will have positive - specific

Question 11

autoantibodies systemic sclerosis

Answer 11

ANA positive in 90%
RF positive in 30%

anti-scl-70 antibodies associated with diffuse cutaneous systemic sclerosis

anti-centromere antibodies associated with limited cutaneous systemic sclerosis