HIV

Question 1

methods of transmission for HIV

Answer 1

blood, semen, vaginal fluid, breast milk

Question 2

80-85% of men and women contract HIV via this

Answer 2

unprotected sex

Question 3

what is more infective in accidental needle stick: hepatitis B or HIV?

Answer 3

Hep B

Question 4

3 routes of infection in pediatric/perinatal HIV infection

Answer 4

transplacental, infected birth canal, ingestion breast milk

Question 5

this HIV variant appears to be less aggressive

Answer 5

HIV-2

Question 6

glycoprotein that mediates binding of CD4 (located on viral envelope of HIV)

Answer 6

gp 120

Question 7

glycoprotein that mediates fusion to cell membranes (located on viral envelopes of HIV)

Answer 7

gp 41

Question 8

major capsid protein that is diagnostic for antibodies (what we measure in screening tests…Ab to this)

Answer 8

p24

Question 9

viral enzymes necessary for HIV reproduction

Answer 9

protease, integrase, reverse transcriptase

Question 10

HIV binds to this molecule on lymphocytes, MP, and glial cells

Answer 10

CD4

Question 11

cells that have CD4 molecule for HIV to bind

Answer 11

lymphocytes, MP, glial

Question 12

where are HIV viruses latent?

Answer 12

unactivated lymphocytes

Question 13

what causes proliferation of HIV after latent phase?

Answer 13

lymphocyte activation (cytotoxic to host cell)

Question 14

ratio of CD4:CD8 in AIDS; what is normal?

Answer 14

.5:1; 2:1

Question 15

CD4 count less than this = AIDS

Answer 15

200

Question 16

co-receptor for CD4-GP 120 binding in *early* HIV infection

Answer 16

CCR5

Question 17

co-receptor for CD4-GP 120 binding in *late* HIV infection

Answer 17

CXCR4

Question 18

these destroy virally-infected cells and terminates early infection of HIV

Answer 18

CD8 (virus-specific)

Question 19

3 factors responsible for progressive development of immune deficiency

Answer 19

loss CD4 and CD8, evolutionary change in virus

Question 20

neoplastic conditions associated with AIDS

Answer 20

Kaposi’s sarcoma, Hodgkins disease, lymphoma

Question 21

GI opportunistic infections in AIDS patients

Answer 21

Giardia, entamoeba, cryptosporidiosis (parasites more common, crypto more deadly)

Question 22

may see these reactivated latent infections in AIDS patients

Answer 22

toxoplasmosis, TB, herpes zoster

Question 23

Kaposi’s sarcoma is associated with this infection

Answer 23

HHV8

Question 24

opportunistic infection in AIDS that is more common in homosexual/bi males; 15% AIDS patients get it

Answer 24

Kaposi’s

Question 25

cells that proliferate in Kaposi's

Answer 25

endothelial cells, SMC, pericytes

Question 26

factors that are related to high efficacy of sexual transmission of HIV

Answer 26

abundant lymphoid tissue, secretions, concurrent infections (or mucosal breaks), local reservoir (as in uncircumcised pts)

Question 27

HIV may adhere to these cells in mucosa (instead of going directly into blood vessels)

Answer 27

dendritic cells

Question 28

these express high amounts of CCR5

Answer 28

genital dendritic cells and GI lymphoid

Question 29

CCR5 receptors are located on these cells

Answer 29

monocytes and lymphocytes (monocytotropic)

Question 30

CXCR4 receptors are located on these cells

Answer 30

T-lymphocytes (lymphotropic)

Question 31

mutation in this switches co-receptor from CCR5 to CXCR4

Answer 31

gp 120

Question 32

CXCR4 dependent virus causes this in lymphoid tissue --\> bind to wide range of T cells (naive and thymocytes) --\> rapid loss of lymphoid tissue

Answer 32

syncytia formation

Question 33

early in HIV infection, these block co-receptor binding --\> therapeutic strategy

Answer 33

inflammatory chemokines

Question 34

early in infection...HIV is primarily an infection of this tissue (in establishing viral reservoir)

Answer 34

lymphoid tissues

Question 35

these provide transport of virus throughout body --\> including CNS

Answer 35

MP

Question 36

viral reservoir for HIV located in these cells

Answer 36

follicular dendritic cells

Question 37

entry and transport of HIV occurs in these cells

Answer 37

mucosal dendritic cells

Question 38

even with appropriate HAART treatment these cells continue to decline

Answer 38

mononuclear cells and lymphocytes

Question 39

early CD4 cell loss in these locations in gut allows gut pathogen products to be released into blood stream --\> inflammatory reaction and increase in proliferation --\> apoptosis/cytolysis (in HIV)

Answer 39

Peyer's patches

Question 40

upon activation, CD8 cells become sticky due to these molecules being expressed; what happens to the CD8 cells then?

Answer 40

CD69; retained in lymph node

Question 41

this is responsible for apoptosis of unaffected lymphocytes in HIV

Answer 41

soluble gp 120 (binds to CD4 in absence of virus)

Question 42

2 other mechanisms for decreased immune function in HIV (besides cytolysis)

Answer 42

apoptosis (due to soluble gp120) and blocking of immune function (gp120 binds CD4 and interferes with antigen presentation), toxic lymphokines

Question 43

evolution of virus from CCR5 to CXCR4 co-receptor is associated with this (poor prognosis)

Answer 43

syncytia formation

Question 44

two treatment protocols that help decrease amount of drug-resistant HIV strains

Answer 44

maximal inhibition of viral replication and multiple agents

Question 45

this occurs as a result of initial activation of immune cells by specific and innate (TLR) mechanisms

Answer 45

lymphadenopathy (germinal center hyperplasia) and hypergammaglobulinemia

Question 46

4 things to remember in immune system dysfunction due to HIV

Answer 46

lymphadenopathy (initially), lymph node burn out, good PMN response, atypical infection presentation

Question 47

time it takes for seroversion of HIV to occur

Answer 47

6-12 weeks

Question 48

these HIV tests have specificity and sensitivity \>99%

Answer 48

HIV serology and western blot

Question 49

RNA at this level in blood is undetectable

Answer 49

50/mL

Question 50

strongest indicator of HIV disease progression

Answer 50

CD4 count

Question 51

this is expanded in lymph node --\> signaling polyclonal activation

Answer 51

B cell area

Question 52

occurs when viral particles are found in follicular mantle cells early in HIV infection

Answer 52

marked follicular hyperplasia

Question 53

CNS infection of HIV seen with this chronic inflammatory infiltrate --\> seen in subacute meningoencephalitis

Answer 53

microglial nodules and multinucleated giant cells

Question 54

this occurs as result of proliferating mesenchymal spindle cells that form blood vessels (in HIV)

Answer 54

Kaposi's sarcoma

Question 55

high levels of viral replication, viremia, and widespread seeding of lymphoid tissue are seen in this; when does this develop after infection?

Answer 55

acute retroviral syndrome; 3-6 weeks (lasts 2-4)

Question 56

this is responsible for initial drop in viral titers

Answer 56

anti-HIV CMI

Question 57

CNS dementia caused when HIV infects these cells; what carries the virus to the brain?

Answer 57

microglial cells; infected MP

Question 58

hallmark of original epidemic of AIDS --\> nearly universal opportunistic infection

Answer 58

Pneumocystis pneumonia

Question 59

cause of Non-hodgkins lymphoma (in 3% AIDS) in 30-50% of cases

Answer 59

EBV

Question 60

appearance of this signals deterioration of immune function (in candidiasis)

Answer 60

thrush

Question 61

this is probably cause of invasive carcinoma of uterine cervix in AIDS patients

Answer 61

HPV

Question 62

stain used for Cryptococcus neoformans

Answer 62

india ink

Question 63

has very thick capsule....stained with india ink in CSF

Answer 63

Cryptococcus neoformans