Brainscape's Knowledge GenomeTM

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


See full index

Year 1: Respiratory > Respiratory Immunology > Flashcards

Respiratory Immunology Flashcards

1
Q

what are 2 cytokines which induce an anti-viral state?

A

IFNa and IFNb

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

Name some pro-inflammatory mediators (produced by activated macrophages, mast cells, neutrophils)

A 
TNFa
IL-1
IL-6
C3a
C5a 
and others...
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Which mediator induces the production of ROS/ RNS by macrophages? Secreted by what?

A

IFNg (which is secreted by activated NK cells and effector Th1 cells)

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

Which mediator, secreted by Th cells, promotes proliferation and differentiation of activated CD4+ and CD8+ cells?

A

IL-2

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

Which cytokines are secreted by Th1 cells? What do they do?

A

IFNg, IL-2, TNFa: increases proliferation and activity of macrophages, NK and CD8+ cells , increased proliferation of B cells and production of opsonising Ig (IgG, IgM and IgA), IL-2 and IFNg positively feedback for Th1 production, IFNg inhibits Th2 production.
(for clearance of bacteria, viruses, fungi (intracellular!), promotes inflammation, autoimmune disease, lots of IFNg = fibrosis)

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

Which cytokine, secreted by Th0 cells, stimulates differentiation into Th1?

A

IL-12

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Name an anti-inflammatory cytokine

A

IL-10 (secreted by macrophages once the pathogen has been eliminated)

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

Which cytokine, secreted by Th0 cells, stimulates differentiation into Th2?

A

IL-4

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

Which cytokines are secreted by Th2 cells? What do they do?

A

IL-4, IL-5, IL-10, IL-13
IL-10 is anti-inflammatory
IL-4 positively feedbacks for Th2 cell production, and increases proliferation and activation of eosinophils and mast cells
IL-5 increases proliferation of B cells and class switching to IgE
IL-13 is for airway hyperresponsiveness and mucus hypersecretion
Functions: clearance of parasites (helminths), suppression of inflammation, and allergy and asthma

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

Which cytokines, secreted by Th0 cells, stimulate differentiation in Th17?

A

IL-6 and TGFB

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

Which cytokines does Th17 secrete? What are their functions?

A

IL-17 and IL-22
IL-17 affects epithelium, causing increased recruitment of neutrophils
Il-22 increases cytokine and chemokine production by many cells
Function: clearance of bacteria and fungi (extracellular), promotes inflammation, autoimmune diseases, increased neutrophil infiltration in severe asthma

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

Which cytokine, secreted by Th0, stimulates differentiation into Treg (T regulatory cell)?

A

TGFB

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

Which cytokines does T-reg secrete? What are the functions?

A

IL-10
Decreases the function of macrophages and APCs
Decreases secretion of pro-inflammatory cytokines
Overall: function is suppression of immune response, and protection against autoimmunity

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

variolation

A

development of active immunity through exposure to a less virulent pathogen

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

toxoid vaccine

A

these are for bacteria which secrete toxins
The toxins are detoxified with formalin and so are safe for use in a vaccine. When the immune system receives a vaccine containing a harmless toxoid, it develops active immunity against the natural toxin.
e.g. vaccines against tetanus and diphtheria

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

what are the 3 types of inactive vaccine?

A
  • killed/ attenuated
  • subunit
  • toxoid
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

features of attenutated (killed) vaccines?

A
  • cannot replicate
  • not as effective as live vaccines
  • may need boosters
  • immune response is primarily antibody based (not T cells)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what type of vaccine is the salk polio vaccine?

A

inactive
administered by injection
needs 3 doses
more expensive than salk

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

define adjuvants

A

things added to vaccine to modify the immune response by boosting it, such as to give a higher amount of antibodies and a longer-lasting protection, thus minimising the amount of injected material

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

benefits of inactivated vaccines?

A
  • usually safe (CAN be given to IC individuals)
  • no refrigeration required
  • can be made quickly
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

disadvantages of inactivated vaccines?

A
  • difficult to stimulate an immune response to many killed organisms
  • poor at eliciting T cell responses
  • memory is variable so boosters needed
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

examples of whole cell inactivated vaccines?

A

polio (salk, inactivated), Hep A, rabies, cholera ,plague

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

examples of fractional (subunit) inactivated vaccines?

A

hep B, influenza, acellular pertussis, HPV, anthrax

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

examples of toxoid inactivated vaccines?

A

diphtheria, tetanus

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

subunit vaccines

A

these include only the antigens that best stimulate immune system (e.g. just epitopes sometimes)
chances of adverse reactions are low

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

polysaccharide vaccines

A

bacteria may have polysaccharide sugars on outer capsule, but these generate antibodies with less functional activity - especially in immature immune system
Immunogenicity can be improved by conjugating with an adjuvant (making it into a conjugate vaccine)
Conjugate vaccines convert polysaccharide antigens to protein to ensure there is a B AND T cell response

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

examples of polysaccharide only vaccine?

A
  • pneumococcus

- meningovax

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

examples of polysaccharide conjugated to toxin vaccine?

A
  • Haemophilus influenza type B vaccine

- prevenar (pneumococcus)

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

live attenuated vaccines

A

these contain a weakened version of the living microbe - so can’t cause disease. These elicit strong response and give lifelong immunity with just one or two doses. IC people cannot have live attenuated vaccines because there’s a chance it could cause disease

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

what is the process of “passaging” (which is used in making a live attenuated vaccine)?

A

subculturing of cells–> they get mutations in their new environments, which make them work less well in humans –> so they can then be safely used to vaccinate humans

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

examples of live attenuated vaccines?

A

Viruses: measles, mumps, rubella, chickenpox, yellow fever, rotavirus, smallpox (vaccinia), polio
Bacterial: BCG, oral typhoid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

what type of vaccine is sabin polio vaccine?

A

live attenuated
elicits good antibody response in humans
administered orally (by dropper or on sugar cube)
contains all 3 strains of polio
full immunity requires 3 separate doses (as each strain dominates the response once)
unsafe in IC people
cheap vaccine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

what are sources of passive immunity?

A

maternal antibodies (active transport of maternal IgG in third trimester, breast milk and colostrum contain IgA), therapeutic passive immunisation (pooled normal human immunoglobin, hyperimmune globin, heterologous hyperimmune serum, monoclonal antibody against specific pathogen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

what is pooled immunoglobin?

A

transfer of antibody from an unrelated individual

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

what is hyperimmune globin?

A

Ig from an individual known to have high Ig levels against a specific pathogen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

passive immunisation with monoclonal antibody

A

Palivizumab
mab produced against RSV
given in severe LRTI in high-risk infants, severe CHD, pre-term infants, severe chronic lung disease in under 2 year olds
this provides short term protection
intramuscular injection during RSV season

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Why is it difficult to develop vaccines for some organisms

A
  • chronic or latent infections (TB, Hep C, HIV, Herpes virus)
  • rapidly evolving infections (HIV, influenza)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

hallmarks of immune deficiency

A

SPUR

Serious, Persistent, Unusual, Recurrent infections

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

what are features other than SPUR that suggest primary immune deficiency?

A
  • weight loss or failure to thrive
  • severe skin rash
  • chronic diarrhoea
  • mouth ulceration
  • unusual autoimmune disease
  • family history
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

what are the differences between primary and secondary immune deficiencies?

A
  • secondary are common, primary are rare

- secondary are acquired, primary are hereditary

41
Q

what are some conditions associated with secondary immune deficiency?

A 
HIV
measles
immunosuppressive therapy
anti-cancer agents
corticosteroids
cancer of the immune system (lymphoma, leukaemia, myeloma)
metastatic tumours
malnutrition
renal insufficiency/ dialysis
type 1 and type 2 diabetes
specific mineral deficiencies e.g. zinc, iron
42
Q

clinical features of phagocyte deficiencies?

A
  • recurrent infections at common or unusual sites
  • common bacteria (e.g. Staph aureus) or unusual bacteria (e.g. Burkholderia cepacia)
  • mycobacteria (both TB and atypical mycobacteria)
  • fungi (candida, aspergillus)
43
Q

What is the life cycle of a neutrophil?

A

Stem cells produce neutrophil precursors
Phagocytes and precursors move from bone marrow or from tissues to the blood
There is upregulation of endothelial adhesion markers (acute inflammation occurs). Neutrophils adhere and migrate into tissues
Neutrophils recognize and kill organism
They may activate other components of the immune system

44
Q

failure to produce neutrophils

A

This is failure of stem cells to differentiate along myeloid (bone marrow) lineage
Primary defect: Reticular dysgenesis
Secondary defect: after stem cell transplantation

Or could be specific failure of neutrophil maturation: Kostmann syndrome, Cyclic neutropaenia

45
Q

reticular dysgenesis

A

most severe form of SCID
absence of neutrophils and other myeloid cells and almost complete deficiency of lymphocytes in peripheral blood and lack of innate and adaptive humoral and cellular immunity - leads to fatal septicaemia within days of birth. RBC and platelet production is not affected.

46
Q

Kostmann syndrome

A

Group of diseases that affect myelopoiesis (production of bone marrow and all the cells that arise from it) - causing severe congenital neutropaenia
It’s a failure of neutrophil maturation

47
Q

cyclic neutropaenia

A

rare blood disorder in which there are recurrent episodes of abnormally low neutrophil levels (every 4-6 weeks)

48
Q

management of Kostmann syndrome

A

-Supportive treatment: prophylactic antibiotics, prophylactic antifungals, without treatment there is 70% mortality within 1st year of life
Definitive treatment: stem cell transplant, give Granulocyte colony stimulating factor (G-CSF) - stimulates bone marrow to produce granulocytes and stem cells to release them into bloodstream

49
Q

Leukocyte adhesion deficiency

A

failure to recognise activation markers expressed on endothelial cells. Neutrophils are mobilised, but cannot exit bloodstream
It’s a rare, primary immunodeficiency, caused by genetic defect in leukocyte integrins (CD18)

50
Q

Clinical feature of Laeukocyte Adhesion Deficiency

A
  • recurrent bacterial and fungal infections
  • very high neutrophil blood counts (leucocytosis, which is high WBC count - usually associated with infection)
  • site of infection is in deep tissues, with NO pus formation
51
Q

Defects of direct recognition

A

direct recognition is by PRRs and PAMPs
PRRs recognise bacterial sugars, LPS
there is genetic polymorphism: some of which are associated with increased susceptibility to bacterial infection, but most don’t cause significant disease

52
Q

Defects of indirect recognition

A

Indirect recognition is by opsonins (e.g. complement, antibodies, CRP)
-opsonins bind to receptors on phagocyte surface
BUT defects in opsonin receptors may cause defective phagocytosis
This generally doesn’t cause significant disease
ALSO, any defect of complement or antibodies will result in decreased efficiency of opsonisation

53
Q

failure of oxidative killing mechanisms: chronic granulomatous disease

A

-absent respiratory burst (and so a deficiency of intracellular killing mechanisms of phagocytes, and an inability to generate ROS/ RNS), impaired killing of intracellular microorganisms
CGD is a diverse group of hereditary disease in which certain cells of the immune system have difficulty forming ROS used to kill certain ingested pathogens - leading to an inability to clear organisms, failure to degrade chemoattractants and antigens, persistent accumulation of neutrophils and activated macrophages and lymphocytes - leading to the formation of granulomas in many organs

54
Q

features of chronic granulomatous disease

A 
recurrent deep bacterial infections
recurrent fungal infections
failure to thrive
lymphadenopathy and hepatosplenomegaly
granuloma formation
55
Q

what’s a lab investigation of chronic granulomatous disease?

A
  • NBT (nitroblue tetreazolium test)
  • tests whether neutrophils are able to kill through production of ROS
  • method: feed their neutrophils E-coli, add dye that is sensitive to H2O2, if H2O2 is produced by neutrophils - the dye changes colour
56
Q

treatment of chronic granulomatous disease?

A
  • supportive: prophylactic antibiotics and antifungals

- definitive treatment: stem cell transplant, gene therapy

57
Q

what are defects that could cause problems in defence against intracellular organisms?

A

(defects in the IL-12: IFNg interaction)

  • single gene defects: IFNg receptor deficiency, IL-12 deficiency, IL-12 receptor deficiency
  • these defects could lead to TB, atypical mycobacterial infection, salmonella
58
Q

treatment of phagocyte deficiencies

A

-aggressive infection management: prophylaxis (septrin, intraconazole), oral. IV antibiotics, surgical drainage of abscesses
-definitive therapy (bone marrow transplant)
Specific definitive therapy for CGD: gamma interferon therapy, gene therapy

59
Q

how many hours after infection are the innate, and acquired immune response active?

A 
innate = 0-4 hrs
acquired = >96 hrs
60
Q

what are Peyer’s patches?

A

these are aggregated lymphoid nodules. They are an important part of gut associated lymphoid tissue and are usually found in humans in the lowest portion of the small intestine (mainly in the distal jejunum and the ileum).

61
Q

What’s the life cycle of a T lymphocyte?

A
  1. Arises from haematopoetic stem cells in bone marrow
  2. Exported as immature cells to the thymus
  3. In thymus, undergoes selection - only 10% cells survive. Those that survive proliferate and mature
  4. Mature T lymphocytes enter circulation and reside in lymph nodes and secondary lymphoid follicles. There are billions of distinct T cell clones
62
Q

CD4+ T lymphocytes

A 
These have immunoregulatory functions: they provide co-stimulatory signals which are necessary for activation of CD8+ (produce IL-2, which is a mitogen for both CD4 and CD8 cells) and naïve B cells (provide signal 2 - needed for B cell proliferation, they also provide CD40L) and also for influencing phagocyte function, they produce cytokines, they regulate other lymphocytes and phagocytes
They recognise peptides presented on HLA class II molecules
63
Q

Which cytokines stimulate CD4+ to produce IFNg?

A

IL-12 and IL-2

64
Q

CD8+ T lymphocytes (cytotoxic)

A 
These recognise peptides in association with MHC class I (HLA class I)
They kill cells directly: production of pore-forming molecules e.g. perforin, triggering apoptosis of the target, secreting cytokines e.g. IFNg
CD8+ are important in defence against viral infections and tumours
65
Q

B cells

A

These arise from haematopoetic stem cells in bone marrow
Mature B cells are found mainly in bone marrow, lymphoid tissue, spleen
Functions: antibody production and antigen presentation

66
Q

B lymphocyte development

A

In bone marrow: Stem cells - lymphoid progenitors - pro B cells - pre B cells
Then export of IgM B cells from bone marrow: IgM B cells develop into either IgM/ IgA/ IgE/ IgG B cells, which then develop into IgM/ IgA/ IgE/ IgG plasma cells

67
Q

activation of B lymphocytes

A

They encounter antigen in lymph nodes
If provided with appropriate signals from T lymphocytes: stimulated B cells rapidly proliferate
They undergo genetic hypermutation
Then there is further differentiation into long-lived plasma cells and plasma cells which produce antibody

68
Q

What condition can cause failure of differentiation of myeloid lineage (and so cause failure of production of lymphocytes, neutrophils…)

A

reticular dysgenesis

69
Q

what is the term for defects of lymphoid precursors?

A

Severe combined immunodeficiency (SCID)

70
Q

clinical phenotype of SCID?

A
  • unwell by 3 months old (maternal IgG from placenta crossing protects the SCID neonate for first 3 months)
  • failure to thrive
  • persistent diarrhoea
  • SPUR infections
  • vaccine associated disease
  • unusual skin disease
  • Graft versus host disease (colonisation of infant’s “empty” bone marrow with maternal lymphocytes
  • family history of early infant death
71
Q

Graft versus host disease

A

Condition that might occur after an allogenic (immunologically incompatible) transplant. In GvHD, the donated bone marrow or peripheral blood stem cells view the RECIPIENT’S body as foreign, and the donated cells/ bone marrow attack the body.

72
Q

hypogammaglobinemia

A

an immune disorder characterised by a reduction in all types of gamma globulins, including antibodies that help fight infection. It may be congenital/ related to medication/ due to a kidney or GI condition/ cancer/ severe burns.

73
Q

Causes of SCID

A 
There are over 20 possible pathways:
-deficiency of cytokine receptors
-deficiency of signalling molecules
-metabolic defects
-defective receptor rearrangements
In SCID, there are different lymphocyte subsets - depending on the exact mutation
74
Q

x-linked SCID

A
  • 45 % of all SCID
  • caused by mutation of a component of IL-2 receptor (which is shared by many other cytokines, resulting in inability to respond to cytokines: so failure of T cell and NK cell development, and immature B cells are produced
75
Q

clinical phenotype of x-linked SCID?

A
  • very low/ absent T cells (because IL-2 is so important for T cell development)
  • normal or increased B cells
  • poorly developed lymphoid tissue and thymus
76
Q

treatment of SCID?

A
  • prophylactic: avoid infections (prophylactic antibodies, antifungals, no vaccines), aggressive treatment of infections, antibody replacement by IV Ig
  • Definitive treatment: stem cell transplant from HLA identical sibling, SCID patients are ideal for gene therapy (stem cells can be treated ex vivo to express missing component)
77
Q

DiGeorge Syndrome

A

developmental defect of 3rd/ 4th pharyngeal pouch, due to deletion at chromosome 22q11.
It’s a complex disorder. Results in failure of thymic development, leading to T cell immunodeficiency (nowhere for T cells to mature), congenital heart defects, cleft palate, hypocalcaemia secondary to hypoparathyroidism, developmental delay, psychiatric disorders

78
Q

What kind of infections will someone with DiGeorge syndrome get?

A
  • recurrent viral: due to CD8 cells being essential in killing of virally infected cells
  • recurrent bacterial: due to T cells being essential in helping B cells make Ig
  • frequent fungal: due to T cells being essential for fungal defence
79
Q

In lab blood tests of someone with DiGeorge Syndrome, what would be found (regarding T cells, B cells, NK cells)?

A
  • absent or decreased no. of T cells (and defective T cell activation response)
  • normal or increased B cells (low IG, IgA, IgE, and poor Ig responses to specific pathogens)
  • normal NK cell numbers
80
Q

management of DiGeorge Syndrome

A
  • correct metabolic and cardiac abnormalities
  • prophylactic antibiotics
  • early and aggressive treatment of infection
  • some patients need Ig replacement
  • T cell function improves with age (possible extrathymic maturation of T cells)
81
Q

what are disorders of T cell effector function?

A
  • cytokine production
  • cytotoxicity
  • T-B cell communication
82
Q

defect of T cell effector function: cytokine production

And what types of infection could this lead to?

A

This is a deficiency resulting in susceptibility to infection (e.g. defects in IL12, IL12 receptor, IFNg, IFNg receptor)
Could lead to : TB, atypical mycobacteria, BCG infection after immunisation, deep fungal infections such as aspergillus

83
Q

Bare lymphocyte syndromes (a failure of expression of HLA molecules)

A

condition caused by mutations in certain genes of the MHC or involved with the processing and presentation of MHC molecules. It’s a form of SCID, BUT as a contrast to SCID: bare lymphocyte syndrome doesn’t cause decreased T and B cell counts, as the development of these cells is not impaired. Diarrhoea can be among associated conditions.

84
Q

Autoimmune lymphoproliferative syndromes (ALPs) (failure of normal apoptosis)

A

rare genetic disorder of abnormal lymphocyte survival caused by defective Fas mediated apoptosis. Normally after infectious insult, the immune system down-regulates by increasing Fas expression on activated B and T lymphocytes and Fas-ligand on activated T lymphocytes. Fas and Fas-ligand interactions trigger apoptotic cascade - leading to apoptosis. Patients with ALPs have a defect in this apoptotic pathway - leading to chronic non-malignant lymphoproliferation, autoimmune disease and secondary cancers

85
Q

clinical features of T cell deficiencies

A
  • recurrent infections (viral, bacterial, fungal, intracellular pathogens e.g. mycobacteria)
  • opportunistic infections
  • malignancies at young age
  • autoimmune disease
86
Q

Investigation of T cell deficiencies

A

1st line:
-total WCC and differential
-serum Ig and protein electrophoresis (surrogate marker of functional T cells)
-quantitation of lymphocyte subpopulations
2nd line:
-functional test of T cell activation and proliferation (may be useful if signalling or activation defects are suspected)
-additional tests of lymphocyte lineage
-an HIV test is essential

87
Q

clinical presentation of Ig deficiencies

A

-recurrent bacterial infections (upper and lower respiratory tract, recurrent GI infections, often common organisms, viral infections are less common but may occur)

88
Q

Name 2 antibody mediated autoimmune diseases

A
  • idiopathic thrombocytopaenia

- autoimmune haemolytic anaemia

89
Q

idiopathic thrombocytopaenia (an Ig mediated autoimmune disease)

A

This is an isolated low platelet count with normal bone marrow and the absence of other causes of thrombocytopaenia

90
Q

autoimmune haemolytic anaemia (an Ig mediated autoimmune disease)

A

This occurs when antibodies directed against a person’s own RBCs cause them to burst (lyse), leading to insufficient plasma concentration. Lifetime of RBCs is reduced to just a few days in serious cases. Intracellular components of the RBCs are released into circulating blood and tissues - causing characteristic symptoms

91
Q

Bruton’s x-linked hypogammaglobobulinaemia (failure to produce mature B cells)

A

This is a rare genetic disorder in which the WBC formation process doesn’t generate mature B cells, which manifests as a complete or near-complete lack of proteins called gamma globuling, including antibodies, in the person’s bloodstream. This impairs the immune system.
In this condition: there are on circulating B cells, no plasma cells, no circulating antibody after the first 6 months of life

92
Q

selective IgA deficiency

A

prevalence = 1/600
2/3 are asymptomatic
1/3 have recurrent RTIs
There is a genetic component, but cause as yet unknown
This is a type of hypogammaglobulinaemia. Defined as undetectable serum IgA levels in the presence of normal serum levels of IgM and IgG. It’s the most common of the primary antibody deficiencies. Most people with this are healthy and never diagnosed.

93
Q

Common variable immune deficiency (CVID)

A

an immune disorder characterised by recurrent infections and low Ig levels, especially IgG, IgM and IgA. General symptoms include: high susceptibility to foreign invaders, chronic lung disease, inflammation and infection of the GI tract. Origins of CVID are poorly understood.
In CVID, there is: low IgG, IgA and IgE, recurrent bacterial infections, often associated with autoimmune disease

94
Q

clinical features of CVID

A
  • recurrent bacterial infections (often severe end-organ damage, bronchiectasis, persistent sinusitis, recurrent GI infection)
  • autoimmune disease
  • granulomatous disease
95
Q

x-linked hyper IgM syndrome

A

This is caused by mutation of CD40LG gene (which codes for CD40 ligand- which is expressed on T cells). When CD40L binds CD40 on B cells, the B cell can then switch from producing IgM to producting IgA or IgG. In these patients, however, a lymph nodes biopsy may show poor development of structural and germinal centres because of lack of activation of B cells by the T cells in them

96
Q

clinical features of B cell deficiencies

A
  • recurrent infections (primarily bacterial, often common organisms)
  • opportunistic infections
  • Ig mediated autoimmune disease
97
Q

management of B cell deficiencies

A
  • aggressive treatment of infection
  • Ig replacement (pooled plasma, containing IgG, administered by IV every 3-4 weeks, lifelong treatment)
  • stem cell transplant
98
Q

Differential diagnosis of recurrent bacterial infections and hypogammaglobulinaemia

A
  • primary: antibody deficiency (CVID/ specific antibody deficiency/ other conditions which are rare in adults)
  • secondary: protein loss (protein losing enteropathy/ nephrotic syndrome), or failure of protein synthesis (lymphoproliferative diseases such as chronic lymphocytic leukaemia/ myeloma/ non-Hodgkins lymphoma)
99
Q

in the UK, what is the most important factor to take into account when allocating organs for transplant?

A

the outcome of the transplant

a person’s “value to society” should NEVER be taken into account

Year 1: Respiratory (25 decks)

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