Regarding T cells, which of the following statements is CORRECT T cells are the least common lymphocyte in the blood. The majority of T cells express γδTCR. CD4+ cells are involved in the class I MHC pathway. Helper type 1 cells (TH1) are involved in cellular immunity

T cells are the most common lymphocyte in the blood (66% compared to 15% B cells) The majority of T cells express ⍺β-TCR (10% in the GI tract express γδTCR) CD4+ cells are involved in the Class II MHC pathway Helper T cells - CD4 - Class II MHC - antigens presented on MHC II by APCs Cytotoxic T cells - CD8 - Class I MHC - Class I MHC is expressed by the bodies own cells and allows self-recognition. Helper type 1 cells (TH1) are involved in cellular immunity Secrete IL-2 and gamma-interferon TH2 cells secrete IL4+5 and interact with B cells to stimulate the humoral immune system

Regarding acquired immunity which of the following statements is CORRECT Class I MHC expressed by all nucleated cells are important in viral infection Class II MHC will activate cytotoxic T cells through CD8+ interaction. T cells mature into plasma cells which secrete large quantities of immunoglobulins. B memory cells activate T cells for a greater immune response

Class I MHC expressed by all nucleated cells are important in viral infection Class II MHC will activate cytotoxic T cells through CD4 interaction. B cells mature into plasma cells which secrete large quantities of immunoglobulins B memory cells activate T cells for a greater immune response Think this is the opposite Pretty sure B memory cells just chill in lymphoid tissue until future infections then reproduce more B cells. TH2 cells activate B cells to unleash their full potential

Which is a peripheral lymphoid organ Thymus Langerhans node Peyers patch Bursa of Fabricius

Thymus - central lymphoid Langerhans node - think this is made up, Langerhans cells are real Peyers patch Bursa of Fabricius - In birds, the bursa of Fabricius (Latin: Bursa cloacalis or Bursa fabricii) is the site of hematopoiesis, a specialized organ that, as first demonstrated by Bruce Glick and later by Max Cooper and Robert Good, is necessary for B cell (part of the immune system) development in birds. Mammals generally do not have an equivalent organ; the bone marrow is often the site of both hematopoiesis and B cell development

Regarding immunoglobulins which statement is CORRECT IgA is the most abundant in plasma. IgG and IgM are important in complement activation IgD is important in histamine release. IgE is a large pentamer.

IgG is the most abundant in plasma. IgG and IgM are important in complement activation IgE is important in histamine release. IgM is a large pentamer.

2. Regarding the immune system (a) antibodies play a crucial role in the innate immune system (b) The classical pathway of complement activation is part of adaptive immunity (c) mannose binding lectins are released by microbes, and are important for complement activation (d) C reactive protein is a by-product of various adaptive immunity responses (e) none of the above is true

(a) antibodies play a crucial role in the acquired immune system (b) The classical pathway of complement activation is part of adaptive immunity Classical = antibody-antigen complexes (c) mannose binding lectins are expressed on (some immune cells), and mannose is found on bacterial cell walls. It binds to the lectin and activates the complement system (alternative pathway) , (d) C reactive protein is produced by the liver, and has an uncertain role in immunity

3. Regarding the immune system (a) T lymphocytes make up 30% of circulating lymphocytes (b) humoral immunity is part of the innate immune response (c) cell mediated immunity provides defence against intracellular organisms (d) NK cells play a pivotal role in cell mediated immunity (e) diverse receptors on lymphocytes show that they are inherently specific for a particular microbe

(a) T lymphocytes make up _66%_ of circulating lymphocytes (b) humoral immunity is part of the acquired immune response (c) cell mediated immunity provides defence against intracellular organisms (d) NK cells play a pivotal role in innate immunity (e) the lymphocyte has great diversity of receptors, compared with the innate immune system, but lymphocytes are not inherently specific for a microbe

4. T cells (a) are activated by soluble antigen (b) have a receptor for antigen (TCR) that is made up of α, β, and γ subunits (c) CD8 molecules bind to the class II MHC molecules (d) with the γδTCR recognise peptides and lipids without the need for antigen presentation (e) receptor recognises a very limited number of peptides

(a) B cells are activated by soluble antigen. T cells require presented antigen (b) have a receptor for antigen (TCR) that is made up of α, β, and _γdelta_ subunits (c) CD8 molecules bind to the _class I_ MHC molecules (Cytotoxic T cells) CD4 -\> Class II (TH cells) (d) with the γδTCR recognise peptides and lipids without the need for antigen presentation (e) receptor recognises a very large number of peptides

Immunity ( 5% ) Flashcards by Michael Jordan

Which of the following is not part of the innate immune system

Complement
Natural killer cells
B cells
Dendritic cells

B cells

B cells are part of the acquired immune system, along with T-cells

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Which of the following is not part of the acquired immune system

T cells
Natural Killer cells
B cells
Immunoglobulins

Natural Killer cells

Are part of the innate immune system, along with complement, dendritic cells (and endothelial and epithelial cells sometimes)

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All of the following are monomers except

IgM

Pentamer

IgA can be monomer, dimer, or trimer, otherwise all Ig is monomer

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Regarding T cells, which of the following statements is CORRECT

T cells are the least common lymphocyte in the blood.
The majority of T cells express γδTCR.
CD4+ cells are involved in the class I MHC pathway.
Helper type 1 cells (TH1) are involved in cellular immunity

T cells are the most common lymphocyte in the blood (66% compared to 15% B cells)
The majority of T cells express ⍺β-TCR (10% in the GI tract express γδTCR)
CD4+ cells are involved in the Class II MHC pathway
- Helper T cells - CD4 - Class II MHC - antigens presented on MHC II by APCs
- Cytotoxic T cells - CD8 - Class I MHC - Class I MHC is expressed by the bodies own cells and allows self-recognition.
Helper type 1 cells (TH1) are involved in cellular immunity
- Secrete IL-2 and gamma-interferon
- TH2 cells secrete IL4+5 and interact with B cells to stimulate the humoral immune system

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Regarding acquired immunity which of the following statements is CORRECT

Class I MHC expressed by all nucleated cells are important in viral infection
Class II MHC will activate cytotoxic T cells through CD8+ interaction.
T cells mature into plasma cells which secrete large quantities of immunoglobulins.
B memory cells activate T cells for a greater immune response

Class I MHC expressed by all nucleated cells are important in viral infection
Class II MHC will activate cytotoxic T cells through CD4 interaction.
B cells mature into plasma cells which secrete large quantities of immunoglobulins
B memory cells activate T cells for a greater immune response
- Think this is the opposite
- Pretty sure B memory cells just chill in lymphoid tissue until future infections then reproduce more B cells.
- TH2 cells activate B cells to unleash their full potential

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Which of the following is not an action of immunoglobulin’s

Blocking the action of toxins
Blocking the attachment of pathogens
Opsonisation of pathogens
Cleaving C3 -> C3a and C3b through the alternative pathway.

Cleaving C3 -> C3a and C3b through the classic pathway

Alternative pathway is triggered by contact with various viruses, bacteria, fungi, tumours

Lectin pathway activated when lectin binds mannose groups in bacteria.

Complement system complements the effects of antibodies.

Ultimately help by:

Opsonisation (C3b), chemotaxis (C5a), and cell lysis
Bridge from innate to acquired immunity by acticating B cells and aiding immune memory
Help dispose of waste products after apoptosis

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Which of the following is not an antigen presenting cell

Natural killer cells
Activated T cells
B cells
Dendritic cells

Natural killer cells

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Regarding dendritic cells, which of the following is INCORRECT

Langerhans cells are immature cells found in the epithelium
Have no role in the acquired (secondary or adaptive) immune response
Are the most important antigen presenting cells
Produce cytokines that can inhibit viral infection

Have no role in the acquired (secondary or adaptive) immune response

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Which is a peripheral lymphoid organ

Thymus
Langerhans node
Peyers patch
Bursa of Fabricius

Thymus - central lymphoid
Langerhans node - think this is made up, Langerhans cells are real
Peyers patch
Bursa of Fabricius - In birds, the bursa of Fabricius (Latin: Bursa cloacalis or Bursa fabricii) is the site of hematopoiesis, a specialized organ that, as first demonstrated by Bruce Glick and later by Max Cooper and Robert Good, is necessary for B cell (part of the immune system) development in birds. Mammals generally do not have an equivalent organ; the bone marrow is often the site of both hematopoiesis and B cell development

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Regarding immunoglobulins which statement is CORRECT

IgA is the most abundant in plasma.
IgG and IgM are important in complement activation
IgD is important in histamine release.
IgE is a large pentamer.

IgG is the most abundant in plasma.
IgG and IgM are important in complement activation
IgE is important in histamine release.
IgM is a large pentamer.

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A 6yers old female presents to the ED with lethargy, polydipsia, polyuria. Blood sugar reads>20mmol/l. The mechanism of disease is the following?

a) Type II HSR
b) Type I HSR
c) Type IV HSR
d) Type III HSR

c) Type IV HSR

Type IV= type I diabetes mellitus

Antigens of pancreatic islet B cells (insulin, glutamic acid decarboxylase, others)

Mechanism of disease insulitis (chronic inflammation in islets), destruction of B cells

Causes IDDM-type 1 DM

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Which hypersensitivity reaction is poststreptococcal glomerulonephritis?

Type II HSR
Type I hypersensitivity reaction (HSR)
Type IV HSR
Type III HSR

Acute rheumatic fever is a type II HSR: streptococcal cell wall antigen; antibody cross reacts with myocardial antigen.

Poststreptococcal glomerulonephritis is a type III HSR: streptococcal cell wall antigen(s); may be planted in glomerular basement membrane

Mnemonic to remember hypersensitivity reactions: “ACID”

Anaphylactic type: type I
Cytotoxic type: type II
Immune complex disease: type III
Delayed hypersensitivity (cell mediated): type IV

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transplant rejection involves

type IV hypersensitivity only
type IV and III hypersensitivity only
type IV, III and II hypersensitivity only
type IV and II hypersensitivity only
type II and III hypersensitivity only

Nick says type IV, III and II hypersensitivity only

I can only find info on Type II and IV

Type II - Hyperacute rejection within minutes, occurs when previously exposed to the antigens, eg blood transfusion or pregnancy

Type III - Unsure, cursory search with google and R&C sheds no light (other than II and IV)

Type IV - direct pathway of rejection, host T-cells recognise graft HLA on graft APCs -> host CD4 intiates TH1 response + CD8 mature into cytotoxic T-cells

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The innate immune system includes the following components EXCEPT

(a) lung surfactant
(b) complement
(c) Natural killer (NK) cells
(d) dendritic cells
(e) B lymphocytes

(e) B lymphocytes

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Regarding the immune system

(a) antibodies play a crucial role in the innate immune system
(b) The classical pathway of complement activation is part of adaptive immunity
(c) mannose binding lectins are released by microbes, and are important for
complement activation
(d) C reactive protein is a by-product of various adaptive immunity responses
(e) none of the above is true

(a) antibodies play a crucial role in the acquired immune system
(b) The classical pathway of complement activation is part of adaptive immunity
- Classical = antibody-antigen complexes
(c) mannose binding lectins are expressed on (some immune cells), and mannose is found on bacterial cell walls. It binds to the lectin and activates the complement system (alternative pathway),
(d) C reactive protein is produced by the liver, and has an uncertain role in immunity

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Regarding the immune system

(a) T lymphocytes make up 30% of circulating lymphocytes
(b) humoral immunity is part of the innate immune response
(c) cell mediated immunity provides defence against intracellular organisms
(d) NK cells play a pivotal role in cell mediated immunity
(e) diverse receptors on lymphocytes show that they are inherently specific for a particular microbe

(a) T lymphocytes make up 66% of circulating lymphocytes
(b) humoral immunity is part of the acquired immune response
(c) cell mediated immunity provides defence against intracellular organisms
(d) NK cells play a pivotal role in innate immunity
(e) the lymphocyte has great diversity of receptors, compared with the innate immune system, but lymphocytes are not inherently specific for a microbe

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T cells

(a) are activated by soluble antigen
(b) have a receptor for antigen (TCR) that is made up of α, β, and γ subunits
(c) CD8 molecules bind to the class II MHC molecules
(d) with the γδTCR recognise peptides and lipids without the need for antigen presentation
(e) receptor recognises a very limited number of peptides

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(a) B cells are activated by soluble antigen. T cells require presented antigen
(b) have a receptor for antigen (TCR) that is made up of α, β, and γdelta subunits
(c) CD8 molecules bind to the class I MHC molecules (Cytotoxic T cells)
- CD4 -> Class II (TH cells)
(d) with the γδTCR recognise peptides and lipids without the need for antigen presentation
(e) receptor recognises a very large number of peptides

The position of immune cells in the spleen is (old paper 2004)

(a) T cells in the medullary cords
(b) B cells in the paracortical regions of the white pulp
(c) Macrophages in the paracortical regions of the white pulp
(d) B cells in the perifollicular regions of the white pulp
(e) Neutrophils cells in the medullary cords

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(a) Plasma cells in the medullary cords of lymph nodes
(b) T cells in the paracortical regions of the white pulp
(c) T cells in the paracortical (areteriolar) regions of the white pulp
(d) B cells in the perifollicular regions of the white pulp
(e) Plasma cells in the medullary cords of lymph nodes

What immune cell type predominates in the perfollicular regions of the white pulp in the spleen? (variation 2004)

(a) T lymphocytes
(b) B Lymphocytes
(c) Macrophages
(d) Plasma cells
(e) Mast cells

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(b) B Lymphocytes

What receptor is present on the surface of all naïve B cells

(a) IgM and IgD
(b) IgM and IgG
(c) IgM and IgA
(d) IgG and IgD
(e) IgG and IgE

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(a) IgM and IgD

(b) IgM and IgG
(c) IgM and IgA - IgA is secreted
(d) IgG and IgD - IgG is formed as part of the adaptive immunity and is seen as a marker for immunity
(e) IgG and IgE - IgE is formed in response to multicellular organism infection

Regarding the proportion of circulating lymphocytes

(a) the B cell make up 50%
(b) the T cell make up 60-70%
(c) neutrophils make up 90%
(d) Plasma cells make up 50%
(e) none of the above figures is correct

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(b) the T cell make up 60-70%

(a) the B cell make up 10-20%
(c) neutrophils are not a lymphocyte, but do make up 90% of circulating WBC usually
(d) Plasma cells are activated B cells, and make up a portion of the 10-20%

B lymphocytes

(a) are the most common circulating lymphocyte
(b) are activated independently of T helper cells
(c) are integral to the cell mediated system of immunity
(d) have a receptor for CMV virus
(e) may be activated by protein and non-protein antigens

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(a) are the most common circulating lymphocyte - T-cells
(b) are activated independently of T helper cells - Require T-helper cells to activate
(c) are integral to the humoral system of immunity
(d) have a receptor for EBV virus (CD21), and are easily infected by this virus
(e) may be activated by protein and non-protein antigens

Natural killer cells

(a) are leukocytes
(b) are a predominant cell in adaptive immunity
(c) have the ability to kill a cell without prior sensitisation
(d) unlike other cells of the immune system, do not produce cytokines
(e) kill cells that over-express class I MHC molecules, such as tumour cells

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(a) are lymphocytes (10-20% of circulating)
(b) are a predominant cell in innate immunity
(c) have the ability to kill a cell without prior sensitisation
- Virally infected, tumour etc
(d) like other cells of the immune system, do produce cytokines
(e) kill cells that under-express class I MHC molecules, such as tumour cells

11. Regarding cytokines * (a) They are specific for one cell type * (b) They are often redundant * (c) Their main role is in innate immunity * (d) They act exclusively as stimulators for immune responses * (e) none of the above

**(b) They are often redundant** **Meaning their functios often overlap** * (a) They are specific for *multiple* cell type * (c) Their main role is in *innate, adaptive immunity and inflammatory responses* * (d) They act as *stimulators for immune responses, and inhibitory (IL-10, TGF-β)*

The class I major histocompatibility complex (MHC) * (a) is expressed on all cells of the body * (b) is encoded for on the short arm of chromosome 16 * (c) has a low level of polymorphism * (d) are encoded for by three loci designated HLA-A, HLA-B and HLA-C * (e) β-microglobulin on the MHC is expressed on the HLA A locus

* (a) is expressed on all *nucleated* cells of the body, *and platelets* * (b) is encoded for on the short arm of chromosome _6_ * (c) has a *very* *high* level of polymorphism - *every person is different* * **(d) are encoded for by three loci designated HLA-A, HLA-B and HLA-C** * (e) β-microglobulin *is not encoded on the MHC*

Mast cells * (a) are bone marrow derived cells * (b) are the primary cell involved in type II hypersensitivity reactions * (c) inhibit platelet activation, but are otherwise inflammatory cells * (d) can phagocytose antigen * (e) none of the above is true

* **(a) are bone marrow derived cells** * (b) are the primary cell involved in type _I_ hypersensitivity reactions * (c) *Release PAF so must activate platelets*, but are otherwise inflammatory cells * (d) _cannot_ phagocytose antigen

Regarding mast cells, which statement is false * (a) They can degranulate with exposure to morphine * (b) They are activated with cross linking of high affinity IgE Fc receptors * (c) They can degranulate with exposure to C5a * (d) Basophils are similar to mast cells, but are in much higher concentrations in certain tissues (eg the lung) * (e) They can be activated by IL-8

(d) Basophils are similar to mast cells, *but are in much smaller concentrations, and _are circulating:_ their functions in anaphylaxis have not been well established*

Examples of primary mediators released by Mast cells would be * (a) cytokines * (b) leukotrienes * (c) Platelet activating factor * (d) heparin * (e) Prostaglandin D2

**(d) Proteoglycans such as heparin, biogenic amines such as histamine, enzymes such as chymase, tryptase** Primary mediators are ones pre-formed in granules

An example of secondary mediators released by Mast cells would be * (a) histamine * (b) platelet activating factor * (c) heparin * (d) chymase * (e) tryptase

(b) platelet activating factor and cytokines, leukotrines,

In systemic anaphylaxis * (a) the severity of the response is proportional to the concentration of the antigen * (b) there is widespread oedema, but the larynx is spared * (c) a previous history of some form of allergy is always present * (d) the symptoms usually follow administration of foreign proteins * (e) hives are not a feature

**(d) the symptoms usually follow administration of foreign proteins** * (a) the severity of the response is proportional to the *level of sensitivity to the antigen (and can occur with minute quantities)* * (b) there is widespread oedema, *with striking contraction of the respiratory bronchioles and larynx* * (c) a previous history of some form of allergy is usually, *but not always* present * (e) hives, *hoarseness (larynx), vomiting, abdominal cramps, etc* are a feature

Complement membrane attack complex can be activated by * (a) IgE * (b) IgA * (c) IgD * (d) IgG * (e) none of the above

(d) IgG and IgM

Regarding hypersensitivity reactions * (a) the presence of antibody-antigen complexes in the circulation implies disease * (b) Type III hypersensitivity is generally due to reactions against endogenous antigens * (c) Pemphigus vulgaris is an example of complement-mediated inflammation * (d) The TH1-type helper cell promotes the synthesis of IgE in type I hypersensitivity reactions * (e) In type III hypersensitivity, immune complexes are typically deposited in vessel walls

**(e) In type III hypersensitivity, immune complexes are typically deposited in vessel walls** * (a) the presence of antibody-antigen complexes in the circulation *does not* imply disease * (b) Type III hypersensitivity is generally due to reactions against *exogenous* antigens (*but can occur due to endogenous antigens eg SLE)* * (c) Pemphigus vulgaris is an example of *antibody-mediated cellular dysfunction; in this case, against desmosomes, which disrupt intercellular junctions in epidermis* * (d) The _TH2_-type helper cell promotes the synthesis of IgE in type I hypersensitivity reactions

In type III hypersensitivity reaction, * (a) phase 2 begins a week after exposure to antigen * (b) small or intermediate size antigen-antibody complexes are more likely to cause this disease process * (c) wherever the complexes deposit, the tissue damage is similar * (d) phase 3 begins approximately 10 days after exposure to the antigen * (e) all of the above is true

**(e) all of the above is true**

Central tolerance * (a) means that in a normal individual, T cells bearing receptors for autoantigens are never present * (b) prevents immature B cells from reacting to self, as they undergo apoptosis if exposed to membrane bound antigen within the bone marrow * (c) occurs for B cells in the thymus * (d) describes a state of anergy towards antigen presenting cells * (e) none of the above is true

No answer given, either B or E * (a) means that in a normal individual, T cells bearing receptors for autoantigens are never present - *central is not 100%, hence peripheral tolerance* * **(b) prevents immature B cells from reacting to self, as they undergo apoptosis if exposed to membrane bound antigen within the bone marrow - *but are more likely to just modify their antigen receptor (receptor editing)*** * (c) occurs for B cells in the *bone marrow (T cells in the Thymus)* * (d) describes a state of anergy towards antigen presenting cells - *this is peripheral tolerance, not central* * (e) none of the above is true

Peripheral tolerance is maintained by all of the following mechanisms except * (a) Anergy * (b) deletion of T-cells that express high affinity for self antigens during maturation in the thymus * (c) clonal deletion by activation-induced cell death * (d) Suppression by regulatory T cells * (e) Antigen sequestration

(b) deletion of T-cells that express high affinity for self antigens during maturation in the thymus This is a central tolerance mechanism

Antigen sequestration is * (a) the phagocytosis of bacteria by leukocytes * (b) the removal of self recognising lymphocytes from the lymphocyte population * (c) where tissues in which antigens are located do not communicate with blood or lymph * (d) the uptake of antigen by Peyer’s patches * (e) the presentation of antigenic products on MHC II molecules

(c) where tissues in which antigens are located do not communicate with blood or lymph eg brain, testis, eye: immune privileged sites

Concerning the mechanisms of autoimmune disease * (a) the actual genes associated with most autoimmune diseases is now known * (b) normal MHC molecules are incapable of presenting self antigens * (c) few autoimmune diseases are associated with preceding infections * (d) molecular mimicry may play a role in the development * (e) these diseases can spontaneously resolve, a process known as epitope spreading

**(d) molecular mimicry may play a role in the development** Most genes are not known (just the general region) Normal MHC *are* capable of presenting self-antigen *Many* autoimmune diseases are associated with preceding infections epitope spreading is the process by which concealed antigens become exposed to the immune system, creating the potential for new self recognition

Transmission of HIV * (a) through needlestick injury is approximately 10% * (b) through needlestick injury can be reduced eightfold when a patient is given antiretroviral therapy * (c) in utero is the most common mode of mother-to-infant transmission * (d) from blood transfusion has been eliminated * (e) can be transmitted by mosquito

* (a) through needlestick injury is approximately *0.3%, Hep B 30%* * **(b) through needlestick injury can be reduced eightfold when a patient is given antiretroviral therapy** * (c) *intrapartum, and peripartum* is the most common mode of mother-to-infant transmission * (d) from blood transfusion has *virtually* been eliminated, *but is still possible (1:2x10^7)* * (e) *cannot* be transmitted by mosquito

HIV * (a) is a double stranded RNA virus * (b) has two viral glycoproteins, gp120 and gp41, which are vital for infection of cells * (c) envelope is lipopolysaccharide * (d) has limited variability expressed in its genome * (e) invades CD4+ cells, but does not invade macrophages

* (a) is a *single* stranded RNA virus (only rotavirus is x2 DNA) * **(b) has two viral glycoproteins, gp120 (binds to T cell CD4, change conformation, and binds to chemokine receptor CCR5/ CXCR4) and gp41, which fuses into the cell membrane, which are vital for infection of cells** * (c) envelope is a *lipid bilayer* *from the host cell* * (d) has *tremendous variability* expressed in its genome, and it is this variability that prevents a vaccine. * (e) invades *CD4+ cells, dendritic cells and macrophages*

Concerning HIV * (a) accumulation of T tropic virus is a sign of the final rapid phase of disease progression * (b) M-tropic strains use CCR5 chemokine receptor to infect host cells * (c) T-tropic strains use CXCR4 chemokine receptor to infect host cells * (d) M-tropic viruses are the dominant virus type found in newly infected individuals * (e) all of the above is true

**(e) all of the above is true** M-tropic strains develop into T tropic strains owing to gp120 mutation. T-tropic viruses can infect immature T cells, and T cell precursors, seriously depleting T cell numbers. Latent infection is ceased when the T cell is mobilised and the cDNA of the virus is replicated.

Concerning HIV infection * (a) Infected monocytes transport the virus to the brain * (b) The type of virus that infects the microglia is M-tropic * (c) Neurons are infected by HIV * (d) Macrophages are easily destroyed by HIV virus replicating in the phagolysosome * (e) A and B are true

**(a) Infected monocytes transport the virus to the brain** **(b) The type of virus that infects the microglia is M-tropic, pointing to the fact that T cells are excluded from the immune privileged site** **e) is right - A + B** Neurons are *not* infected by HIV - neurologic effects are thought to be indirectly due to viral products and soluble factors produced by infected microglia Macrophages *are not destroyed* by HIV, making them a good reservoir for the disease

Concerning HIV complications * (a) Invasive candidiasis is common * (b) Atypical pneumonia caused by Mycoplasma pneumoniae is one of the sentinel infections * (c) Toxoplasmosis is responsible for 50% of mass lesions in the CNS of HIV patients * (d) 5% of infected individuals will develop a malignancy * (e) Kaposi sarcoma is more common in patients who acquired the disease parenterally

* (a) Invasive candidiasis is *uncommon (more likely in those with drug-induced neutropenia or indwelling catheters)* * (b) Atypical pneumonia caused by Mycoplasma pneumoniae is *not* one of the sentinel infections (only atypical mycobacteria count) * *pneumocystis jiroveci pneumonia is one of the sentinal infections* * **(c) Toxoplasmosis is responsible for 50% of mass lesions in the CNS of HIV patients** * (d) *25-40%* of untreated infected individuals will develop a malignancy * (e) Kaposi sarcoma is *20x more common* in patients who acquired the disease _sexually_

Immunity ( 5% ) Flashcards

(43 cards)