Exam 5 lecture 2 (pt 2)

Question 1

Target cell of the HIV retrovirus

Answer 1

Primary target cell of HIV is the CD4 T helper/inducer lymphocyte.

Infected CD4 cells are impaired from normal functions, and used for viral replication.

Question 2

3 major routes of transmission of HIV

Answer 2

1. exposure of mucous membranes or damaged tissue to infected body fluids.
2. blood stream exposure to infected body fluids
3. Mother to child.

Unlike hepatitis, HIV can be transmitted via breastmilk

Question 3

What are the stages of HIV infection? symptoms? Viral load?

Answer 3

stage 0- Acute retroviral syndrome
stage (flu like illness, fever etc..) Viral load is detectable

stage 1- chronic HIV infection, (asymptomatic),

Stage 2- AIDS (symptomatic)

Question 4

screening recommendations for HIV AIDS

Answer 4

Patients aged 13-64 should be tested annually.

All pregnant women as early as possible during pregnancy. COnsider repeat in 3rd trimester.

All TB patients

Question 5

What are the different tests available for HIV infection

Answer 5

1st -4th gen
nucleic acid testing

Question 6

What biomarker is detected with nucleic acid test? How many days after infection does it appear?

Answer 6

RNA

10 days

Question 7

4th gen HIV tests pick up what biomarkers?

Answer 7

p24 biomarker
14 days

Question 8

what do 3rd gen HIV tests pick up on? What day can it pick up on

Answer 8

IgM
20-23 days

Question 9

What is the first testing given for suspected HIV patient (diagnosis)?

Answer 9

HIV 1/2 antigen/antibody immunoassay

Question 10

What do we do if the HIV 1/2 antigen/antibody immunoassay is positive? Negative?

Answer 10

Negative- Negative for HIV-1 and HIV-2 antibodies and p24 Ag (keep in mind the serial conversion window (viral replication)

Positive- confirm with HIV1/HIV2 antibody differentiation immunoassay

Question 11

What are the different results that we can see with HIV-1/HIV-2 antibody differentiation immunoassay

Answer 11

HIV-1 (+), HIV-2(-)- HIV 1 detected

HIV-1 (-), HIV-2 (+)- HIV 2 antibody detected

HIV-1 (+), HIV-2 (+)- HIV antibodies detected

HIV-1 (-) or indeterminate and HIV-2 (-) or indeterminate

Question 12

What does it mean if a person tests positive for HIV-1/2 antigen/antibody immunoassay and negative for both HIV 1 and 2? What should we do next?

Answer 12

acute HIV infection. Look for nucleic acid test which are detected faster than antibody

HIV-1 NAT (+)- acute HIV infection
HIV -1 NAT (-)- negative for HIV

Question 13

What is a test available at home for HIV OTC? Serial conversion rate?

Answer 13

OraQuick in home test. result available in 1-20 mins

3 months

Question 14

What are the two HIV surrogate markers

Answer 14

CD4 T lymphocyte cell count

HIV RNA PCR (viral load)