Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Year 5 - Pathology ICSM1 > Immunology 2 - Primary immune deficiencies parts 1 & 2 > Flashcards

Immunology 2 - Primary immune deficiencies parts 1 & 2 Flashcards

1
Q

Recall 3 infections that can cause immunodeficiency

A

HIV
Measles virus
Mycobacterial infection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Recall 3 diseases of neutrophil deficiency

A

Reticular dysgenesis
Kostmann syndrome
Cyclic neutropenia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the cause of Leukocyte adhesion deficiency?

A

CD18 deficiency - failure to express this ligand means they cannot exit the bloodstream

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What will be the most obvious abnormal result on the blood count in leukocyte adhesion deficiency?

A

Very high neutrophils (they cannot exit the bloodstream)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is chronic granulomatous disease?

A

A failure of phagocytic oxidative killing mechanisms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Recall 2 tests that are useful in the investigation of chronic granulomatous disease

A
  1. Nitroblue tetrazolium test (negative = blue, positive = yellow)
  2. Dihydrohodamine flow cytometry test (negative = fluorescent)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Which innate immunodeficiency is characterised by severe chickenpox and disseminated CMV infection?

A

Classic Natural Killer cell deficiency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Which innate immunodeficiency is characterised by recurrent infections with hepatosplenomegaly and abnormal dihydrohodamine test (does not fluoresce)?

A

Chronic granulomatous disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Which innate immunodeficiency is characterised by recurrent infections with no neutrophils on FBC?

A

Kostmann syndrome (Mutation in Hax-1)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Which innate immunodeficiency is characterised by infection with atypical mycobacterium and salmonella, and a normal FBC?

A

Cytokine deficiency- IL-12, IL-12R, IFNg, IFNgR deficiency
- IL-12-IFNg network is important in control of mycobacteria infection
o Infection activates IL-12-IFNg network
§ Infected macrophages are stimulated to produce IL-12
§ IL-12 induces T cells to secrete IFNg
§ IFNg feeds back to macrophages and neutrophils
§ This leads to stimulation of production of TNF
§ NADPH oxidase is subsequently activated
§ Oxidative pathways are then stimulated

These patients are unable to form granulomas and have recurrent or atypical mycobacterial infections

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Which innate immunodeficiency is characterised by recurrent infections with high neutrophil count on FBC but no abscess formation?

A

Leukocyte adhesion deficiency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

With which innate immunity deficiency is meningococcal septicaemia associated?

A

Deficiency of complement (C1q)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

With which innate immunodeficiency is membranoproliferative nephritis and abnormal fat distribution associated?

A

C3 deficiency with presence of a nephritic factor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What mutation is causative of X-linked SCID?

A

Common gamma chain on chromosome Xq13.1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Describe the phenotype of X-linked SCID in terms of T, B and NK cell numbers

A

T cells: very low or absent

B cells: Normal or increased B cells, but LOW Igs

NK cells: very low or absent

Most common of the SCIDS. Early arrest of T cell and NK cell development and production of immature B cells

Mutation of common g chain on Chromosome Xq13.1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How does adenosine deaminase deficiency affect the immune system?

A

This enzyme is necessary for cell metabolism in lymphocytes.

When it is deficient, there is early arrest of T and NK cell development and very low or absent immature B cells.

X-linked SCID results in normal or increased B cells in contrast

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Describe the phenotype of ADA deficiency in terms of T, B and NK cell numbers

A

All very low or absent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Describe the clinical phenotype of SCID

A
  1. Unwell by 3 months of age
  2. Infections of all types
  3. Failure to thrive
  4. Persistent diarrhoea
  5. Unusual skin disease
  6. Family history of early infant death
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the gene mutation implicated in DiGeorge syndrome?

A

22q11.2 deletion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How does DiGeorge syndrome affect B and T cell levels?

A

Normal B cells

Reduce T cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is bare lymphocyte syndrome type 2?

A

Absent expression of MHC class II causing severe deficiency of CD4+ T helper cells –> results in low IgG OR IgA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What inherited immunodeficiency might cause a profound deficiency of CD4+ T cells specifically?

A

Bare lymphcoyte syndrome type 2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is reticular dysgenesis?

A

Failure of stem cells in BM to differentiate along myeloid or lymphoid lineage (AK2 deficiency)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is Kostmann syndrome?

A

Failure of neutrophils to mature - causes a congenital neutropenia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What is cyclic neutropaenia?

A

Autosomal dominant episodic neutropenia every 4-6 weeks
ELA-2 mutation (neutrophil elastase)
May be treated with G-CSF

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What are the features of chronic granulomatous disease?

A

Absent respiratory burst, leading to:

  • Excessive inflammation
  • Granuloma formation
  • Lymphadenopathy
  • Hepatosplenomegaly
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What immunodeficiency are recurrent skin and mouth infections most likely to be indicative of?

A

Phagocyte deficiency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Which phagocyte deficiency has absent neutrophils and normal leukocyte adhesion molecules?

A

Kostmann syndrome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Which phagocyte deficiency has absent CD18 and increased neutrophils?

A

Leukocyte adhesion deficiency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Which phagocyte deficiency has normal neutrophil levels and leukocyte adhesion markers, an abormal NBT/DHR test and pus is produced?

A

Chronic granulomatous disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Which phagocyte deficiency has normal neutrophil levels and leukocyte adhesion markers, a normal NBT/DHR test but no pus is produced?

A

Cytokine deficiency (IL12/IFN gamma pathway)

32
Q

Describe the classical pathway of complement activation

A

Antibody-antigen complex (involves C1,C3,C4)

33
Q

Describe the MBL pathway of complement activation

A

Activation of complement by the direct binding of MBL to microbial cell surface carbohydrates- involves C2 & C4

34
Q

Describe the alternate pathway of complement activation

A

Involves bacterial cell wall

35
Q

Name 3 encapsulated bacteria

A

NHS
Neisseria meningitides
Haemophilus influennzae
Streptococcus pneumoniae

36
Q

What does classical complement pathway deficiency increase susceptibility to?

A

SLE (particularly C1q)

37
Q

Susceptibility to encapsulated bacteria may be indicative of what type of immunodeficiency?

A

Complement deficiency

Encapsulated bacteria: Neisseria meningitidis, Haemophilus influenzae, Streptococcus pneumonia

38
Q

How does SLE affect complement?

A

Persistent production of immune complexes –> activation of classical pathway –> low levels of C3 and C4 (functional complement deficiency)

39
Q

What are the standard tests in suspected complement deficiency?

A

C3
C4
CH50
AP50

40
Q

What does CH50 measure?

A

Classical complement pathway

41
Q

What does AP50 measure?

A

Alternative complement pathway

42
Q

Which complement function test would be abnormal in C1q deficiency?

A

CH50

43
Q

Which tests would be abornmal in C9 deficiency?

A

CH50 and AP50

44
Q

Which complement deficiency is most associated with developmental SLE?

A

C1q deficiency

45
Q

In which complement pathway is properdin found?

A

Alternative

46
Q

Which complement deficiency is most associated with meningococcal disease?

A

C7 deficiency

47
Q

How do phagocytes detect pathogens at the site of infection?

A

Expression of genetically-coded receptors such as toll-like receptors, which detect PAMPs

48
Q

What type of B cells produce IgM?

A

Pro B cells

49
Q

What is the most severe form of SCID?

A

Reticular dysgenesis

50
Q

What is the most common form of SCID?

A

X-linked SCID

51
Q

Why are SCID babies initially protected?

A

IgG of mother

52
Q

Why does Di George syndrome produce immunodeficiency?

A

Abnormality of development of pharyngeal pouch –> absent thymus

53
Q

What test can be used to see lymphocyte subsets in a blood sample?

A

FACS (flow cytometry)

54
Q

What is Bruton’s X-linked hypogammaglobinaemia?

A

Abnormality in B cell tyrosine kinase gene: Pre B cells don’t mature so no Ig after around 3 months
Only affects boys

55
Q

What is the inheritance pattern of hyper IgM syndrome?

A

X linked

56
Q

What is hyper IgM syndrome?

A

B cell maturation defect which results in T cells not expressing CD40 (Failure of T cell co-stimulation)

57
Q

In which disease is CD40 not expressed on activated T cells?

A

Hyper IgM syndrome

58
Q

Which syndrome is characterised by elevated IgM and undetectable IgA, IgE and IgG?

A

Hyper IgM syndrome

Mutation in CD40L on T cells

AKA X-linked Hyper IgM syndrome

59
Q

Which disease is marked by reduction in IgG with low either IgA/IgM

A

Common variable immune deficiency

60
Q

What are the clinical features of common variable immune deficiency?

A
  • Recurrent severe bacterial infections
  • Pulmonary disease (in particular granulomatous interstitial lung disease)
  • GI disease
  • Also a risk factor for developing atypical SLE
  • Non-Hodgkin’s lymphoma- at quite high risk

Marked reduction in IgG, sometimes also low IgA/E
Failure of differentiation/ function of B lymphocytes
Cause is unknown (may be due to MHCIII), typically diagnosis of exclusion

61
Q

What % of Selective IgA deficiency patients are symptomatic, and what are these symptoms?

A

1/3

Recurrent GI and resp infections

62
Q

How are B cell deficiencies managed?

A

Lifelong immunoglobulin replacement

63
Q

Recall the levels of T, B and NK cells in ADA deficiency

A

All very low or absent

64
Q

What mutation causes reticular dysgenesis?

A

Adenylate kinase 2 (AKA2) - a mitochondrial energy enzyme

65
Q

What mutation causes kostmann syndrome?

A

HCLS1-associated protein X-1 (HAX-1)

66
Q

What mutation causes cyclic neutropaenia?

A

Neutrophil elastase (ELA-2)

67
Q

What can be used to treat chronic granulomatous disease?

A

Interferon gamma (as this stimulates macrophages)

68
Q

What are the symptoms of DiGeorge syndrome?

A 
CATCH 22
Cardiac abnormalities (especially ToF) 
Abnormal facies (low set ears) 
Thymic aplasia 
Cleft palate
Hypoalcaemia/hypoPTHism
Chromosome 22
69
Q

Recall some clinical signs of bare lymphocyte syndrome

A

Hepatomegaly and jaundice

May be associated with sclerosing cholangitis

70
Q

What is the inheritance pattern of Wiskott-Aldrich Syndrome?

A

X linked

71
Q

What mutation causes Wiskott-Aldrich Syndrome?

A

WASP gene mutation (actin cytoskeleton rearrangement which is needed to stabilise T cell-APC interaction)

72
Q

Which immunodeficiency might cause a low IgM with raised IgA and IgE?

A

Wiskott-Aldrich Syndrome

73
Q

What comborbidity does Wiskott-Aldrich Syndrome put you at risk of?

A

Malignant lymphoma

74
Q

What is the prevelance of selective IgA deficiency?

A

1:600

75
Q

Recall 3 clinical features of X-linked hyper IgM syndrome

A

Pneumocysti jiroveci/infections

Recurrent bacterial infections

76
Q

At what age does common variable immune deficiency present?

A

Adulthood

77
Q

Which mutation is most likely to be the cause of CVID?

A

MHC class III - causing aberrant class switching

Year 5 - Pathology ICSM1 (85 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions