Immunology

Question 1

What are SPUR infections? What do they indicate?

Answer 1

Serious, Persistent, Unusual, Recurrent
Indicate immune deficiency

Question 2

What is the main hallmark of immune deficiency?

Answer 2

Recurrent infections

Question 3

Primary immune deficiencies are common. True/False?

Answer 3

False
Rare! Secondary immune deficiencies are common

Question 4

Risk of infection ______ as neutrophil count increases

Answer 4

Decreases

Question 5

How can failure to produce neutrophils arise?

Answer 5

Failure of stem cell differentiation
Failure of neutrophil maturation

Question 6

What is Kostmann syndrome?

Answer 6

Rare autosomal recessive disorder; congenital neutropenia
Clinically presents as (recurrent) infections 2 weeks after birth

Question 7

What is leukocyte adhesion deficiency?

Answer 7

Rare primary immune deficiency where neutrophils fail to bind to endothelial markers - cannot find where infection is!
Genetic defect in CD18

Question 8

What is chronic granulomatous disease?

Answer 8

Failure of oxidative killing due to inability to generate oxygen free radicals

Question 9

Name an important related side effect of anti-TNF therapy

Answer 9

Reactivation of latent TB

Question 10

In congenital neutropenia, neutrophil count is normal. True/False?

Answer 10

False
Low or absent

Question 11

Is there pus formation in congenital neutropenia?

Answer 11

No

Question 12

In leukocyte adhesion deficiency, neutrophil count is low during infection. True/False?

Answer 12

False
It is high

Question 13

Is there pus formation in leukocyte adhesion deficiency?

Answer 13

No

Question 14

In chronic granulomatous disease, neutrophil count is normal. True/False?

Answer 14

True
Would be raised in the acute stage but not once granuloma has formed

Question 15

Is there pus formation in chronic granulomatous disease?

Answer 15

Yes

Question 16

Give examples of definitive management of phagocyte deficiencies

Answer 16

Bone marrow transplant, gene therapy

Question 17

What cells do T cells arise from?

Answer 17

Haemopoetic stem cells in bone marrow

Question 18

Defects in stem cell differentiation in haemopoetic cells causes which fatal condition?

Answer 18

Reticular dysgenesis

Question 19

What is Severe Combined Immunodeficiency (SCID)?

Answer 19

Failure of production of lymphocytes

Question 20

What are some key clinical phenotypes of SCID?

Answer 20

Unwell by 3 months
Diarrhoea
Failure to thrive
Early death

Question 21

Why does SCID present only after 3 months of age?

Answer 21

Maternal IgG protects the infant up to this point

Question 22

In X-linked SCID, which receptor is mutated?

Answer 22

IL2 receptor

Question 23

What is DiGeorge syndrome?

Answer 23

Failed development of the thymus
“Funny looking kid”

Question 24

Which chromosome is deleted in DiG syndrome?

Answer 24

22q11

Question 25

In DiG syndrome, the thymus fails to develop. What is the consequence of this?

Answer 25

Low/no T cells can mature (thus low T cell numbers)

Question 26

What is common variable immunodeficiency?

Answer 26

Low IgG, IgA and IgE Leads to recurrent infections, often autoimmune

Question 27

Which type of hypersensitivity reaction do allergic diseases come under?

Answer 27

Type 1

Question 28

Define what is meant by allergy

Answer 28

IgE-mediated response to an external antigen

Question 29

Describe the hygiene hypothesis

Answer 29

Decrease in infectious exposure in early life predisposes to increased sensitivity/predisposition to allergic stimuli

Question 30

Allergic reactions typically take a few hours to develop. True/False?

Answer 30

False Can be from within minutes to a couple hours

Question 31

What is the clinical effect of histamine and other inflammatory mediators in the lung?

Answer 31

Bronchoconstriction Vasodilation Increased vascular permeability Mucosal oedema, mucus secretion Yellow sputum

Question 32

What is urticaria? How long does it last?

Answer 32

Hives/rash Lasts typically 6 hrs

Question 33

Name some elective investigations for identifying allergic disease

Answer 33

Skin prick test Challenge testing

Question 34

What would be measured in an acute anaphylactic episode?

Answer 34

Serum tryptase

Question 35

Which drug class should be discontinued prior to skin prick testing?

Answer 35

Antihistamines for 48hrs

Question 36

Corticosteroids should be stopped before skin prick testing. True/False?

Answer 36

False

Question 37

Why is measuring total IgE not useful in diagnosing allergic disease?

Answer 37

IgE can be raised by lots of things - allergy can also occur in the absence of IgE

Question 38

Which drug supposedly blocks mast cell degranulation?

Answer 38

Sodium chromoglycate

Question 39

What disease type is an example of Type I hypersensitivity?

Answer 39

Allergy

Question 40

Type II hypersensitivity involves direct cell killing through which main mechanism/process?

Answer 40

Complement pathway

Question 41

What mediates Type III hypersensitivity?

Answer 41

Immune complexes

Question 42

Which cell type mediates Type IV hypersensitivity?

Answer 42

T cells

Question 43

What term is given to a collection of activated macrophages and lymphocytes?

Answer 43

Granuloma

Question 44

What is the main danger of live attenuated vaccines?

Answer 44

Can cause disease particularly in immunosuppressed individuals

Question 45

Give examples of live attenuated vaccines

Answer 45

Measles and mumps Chickenpox Rubella Smallpox

Question 46

Which Ig is contained in colostrum?

Answer 46

IgA

Question 47

HLA Class II presents to which T cell?

Answer 47

CD4

Question 48

HLA Class I presents to which T cell?

Answer 48

CD8

Question 49

What are the 2 situations where HLA matching is used to allocate donors?

Answer 49

Stem cell transplants Kidney transplants

Question 50

When is HLA matching not used to allocate donors?

Answer 50

Lung, heart and liver transplants

Question 51

Which type of hypersensitivity reaction is acute cellular rejection?

Answer 51

Type IV

Question 52

What is the time-frame over which acute cellular rejection of a transplant takes place?

Answer 52

5-30 days

Question 53

Transplantation of donor tissue between blood groups will always result in hyperacute rejection. True/False?

Answer 53

True

Question 54

Over what time-frame does acute vascular rejection of a transplant occur?

Answer 54

5-30 days

Question 55

Which type of hypersensitivity reaction is acute vascular rejection of a transplant?

Answer 55

Type II

Question 56

What is the most major cause of graft loss?

Answer 56

Chronic allograft failure

Question 57

Over what time-frame does chronic allograft failure occur?

Answer 57

Greater than 30 days