Lecture 4 - HIV infection 1

Question 1

risk factors for HIV

Answer 1

sex with no condom w/partners w/ unknown status
Sharing injection drug needles or syringes
Surgery or blood transfusion in developing country
receiving blood transfusion or clotting factor between 78-85
History of STD

Question 2

2 types of HIV

Answer 2

1 and 2

1 = accounts nearly all cases in US
2 = less virulent, majority of cases in Africa

Question 3

HIV infects mostly….

Answer 3

CD4 receptor of T helper cells
can also infect other CD4+ cells
can also use docking molecules to infect CD4 cells

Question 4

what effectively prevents cure of HIV?

Answer 4

“reservoir”

provirus resting in memory T cells, continues to replicate in protected sites

Question 5

Primary way of transmission HIV

Answer 5

Sexual contact = higher risk for receptive partner
Needlestick injury

Perinatal transmission = during birth and Breast feeding.

Question 6

socioeconomic factors affecting HIV risk

Answer 6

prevalence of HIV and other STDs in community
Higher rates of undiagnosed/untreated STDs
Poverty
Discrimination, stigma, homophobia
Higher rates of incarceration
Language barriers or concerns about immigration status

Question 7

reducing risk of HIV transmission

Answer 7

Condom use
Treatment as prevention = viral load <200copies/ml
Pre-exposure prophylaxis for individuals at high risk
Post-exposure prophylaxis after high-risk exposure

Question 8

HIV screening

Answer 8

everyone 13-64 screened atleast once

every 3-6 months for MSM w/ multiple partners
each visit for STI treatment
Annually for PWID who share equipment
in each pregnancy
patients with TB

Question 9

If both HIV ELISA and NAAT are positive then….

Answer 9

infection is confirmed

Question 10

HIV testing

Answer 10

start with ELISA, if negative you can trust unless its recent exposure

If positive you need to do NAAT

Question 11

Reason for false negative HIV

Answer 11

recent exposure, test 3 months after initial exposure
infants
Dilution of antibody conc due to large volume of blood received

Question 12

Reasons for false positive HIV

Answer 12

recent influenza vaccine
lupus or other AI disease
Participate in HIV vaccine trial
Liver disease
Hemodialysis
Infants

Question 13

Stage 3 lab values

Answer 13

AKA AIDs

CD4 < 200 or < 14%

Question 14

Acute HIV infeciton

Answer 14

Flu-like symptoms
Abrupt onset = 3-14 days
Occurs 5 days - 3 months after HIV exposure
Diagnosis usually missed
Antibody may not be detected

Question 15

baseline labs for patients with HIV

Answer 15

CD4 count for staging
Viral load
Genotypic resistance testing
Hep B/C serologies
CBC, basic chem, LFTs, lipid panel, urinalysis
Preg test

Question 16

what vaccine should you get if you have HIV?

Answer 16

Pneumococcal vaccine
Meningococcal conjugate vaccine & booster
Recombinant zoster vaccine

Question 17

What vaccines should people with Stage 3 not get?

Answer 17

live vaccines

dont want them if CD4 < 200