HIV / AIDS

Question 1

How is HIV transmitted?

Answer 1

1. unprotected sex with infected person
2. sharing infected needles with infected person
3. mother to child during pregnancy, birth, and breastfeeding
4. receiving contaminated blood / blood products

Question 2

How is HIV diagnosed?

Answer 2

• serum antibody detection
• HIV RNA detection / quantification (viral load) - PCR

Question 3

What are the goals of HIV treatment?

Answer 3

1. decrease HIV-associated mortality
2. restore and preserve immune functions
3. increase duration and quality of survival
4. prevent HIV transmission

Question 4

What are the surrogate markers for HIV?

Answer 4

CD4+ cell count and HIV viral load

Question 5

How is CD4+ cell count used?

Answer 5

1. determine urgency to treat
2. assess response to ART (at baseline, then 3-6m upon initiation and every 12m if stable; adequate response = CD4 increase by 50 -150 cells/mm3 in 1st year)
3. assess need for initiating / discontinuing prophylaxis

Question 6

How is HIV viral load used?

Answer 6

• indicator of response to therapy
• measure before initiation, 2-4w after, then every 4-8w until suppression, then every 3-6m after suppression
• suppression usually takes 8-24w

Question 7

What are the benefits of early ART initiation?

Answer 7

• maintain higher CD4 count, prevent irreversible damage
• decrease risk of HIV associated complications
• decrease risk of opportunistic infections
• decrease transmission risk

Question 8

What are the limitations of early ART initiation?

Answer 8

• side effects and toxicity
• risk of drug resistance if incomplete suppression
• transmission of drug resistant virus
• less time for education
• increased total time on medications, increased treatment fatigue
• increased costs

Question 9

What is the definition of AIDS?

Answer 9

CD4 < 200 cells / mm3 or opportunistic infections

Question 10

What are the recommended ART combinations for ART naive HIV patients?

Answer 10

2 NRTI + 1 INSTI
- tenofovir + emtricitabine + bictagravir
- tenofovir + emtricitabine + dolutegravir
- abacavir + lamivudine + dolutegravir
1 NRTI + 1 INSTI
- emtricitabine + dolutegravir (only for HIV RNA < 500,000, no HBV coinfection, ART not started prior to genotypic resistance test / HBV test)

Question 11

What are the available classes of drugs for HIV ART?

Answer 11

NRTI, NNRTI, PI, INSTI, fusion inhibitors, CCR5 antogonist

Question 12

What are the NRTIs?

Answer 12

tenofovir, abacavir, emtricitabine, lamivudine, zidovudine

Question 13

What are the adverse effects of NRTIs?

Answer 13

• mitochondrial toxicity
• N/V/D
• tenofovir: renal impairment, decrease bone mineral density
• abacavir: hypersensitivity, do not rechallenge
• zidovudine: bone marrow suppression, myopathy

Question 14

How to identify an INSTI?

Answer 14

-gravir

Question 15

What are the drug-drug / drug-food interactions for INSTI?

Answer 15

reduced bioavailability with polyvalent cations
B, D, E are CYP3A4 substrates

Question 16

What are the adverse effects of INSTIs?

Answer 16

weight gain, N/D, headache
B, D: increase SCr
R: pyretic, increase creatinine kinase

Question 17

What are the NNRTIs?

Answer 17

efavirenz, rilpivirine

Question 18

Which NNRTI cannot be administered with PPI?

Answer 18

rilpivirine

Question 19

How to identify a protease inhibitor?

Answer 19

-navir

Question 20

What is the fusion inhibitor?

Answer 20

enfuvirtide
(SC injection 2x a day, injection site reactions, and increase risk of bacterial pneumonia)

Question 21

What is a CCR5 antagonist?

Answer 21

maraviroc
(used only in pt whose strain of HIV uses CCR5)
is CPY3A4 substrate