HIV

Question 1

Seven stages of HIV life cycle

Answer 1

Binding - virus binds to CD4 cell

Fusion - once bound, can insert its RNA into host cell

Reverse Transcription - transforms viral RNA to DNA and is now able to enter host nucleus

Integration - inserts its DNA into host DNA

Replication - uses CD4 cell to make long chains of HIV proteins which are building blocks for more HIV

Assembly - these proteins and HIV RNA move to surface of the cell and assemble into immature HIV

Budding - the immature HIV exits CD4 cell, it then releases protease which breaks up the long pro chains into smaller ones which then combine to form mature HIV

Question 2

Normal CD4 count

Answer 2

500-1500

Question 3

When are opportunistic infections likely to strike (CD4 count)

Answer 3

Less than 500

Question 4

Clinical Course of HIV

Answer 4

Early infection (acute)

Clinical Latency (Chronic)

Rapid virus production (converts to AIDS)

Question 5

Early infection (Acute) s/sxs

Answer 5

rapid replication
not detectable by lab tests
no symptoms
infectious
        Seroconversion (3 wks-6 months)
antibodies are detectable
flu-like sxs for several weeks
highly infectious

large amounts of virus in body during this stage

Question 6

Clinical Latency s/sxs

Answer 6

virus levels have stabilized
body is fighting infections
3-12 years
asymptomatic or mild sxs (enlargements of lymph nodes, fatigue, etc.)

HIV reproduces at very low levels, but still active

Question 7

Rapid virus production s/sxs

Answer 7

persistent drop in CD4 T-cell counts
antiviral fight becomes less effective
viral load increases–immune system declines
symptomatic HIV infection–AIDS

Question 8

AIDS-defining illnesses

Answer 8

Fungal
Candidiasis (pulmonary, esophageal) NOT oral
Pneumcystitis jiroveci pneumonia

Viral
CMV
Herpes simplex
     chronic ulcer > 1 month
     pulmonary/esophageal

Protozoal
Toxoplasmosis
Isosporiasis
Cryptosporidiosis (intestinal)

Bacterial
Mycobacterium (TB, avium)
PNA, recurrent
Salmonella septicemia, recurrent

Cancers
Kaposi’s sarcoma
Cervical CA (invasive)
Lymphomas

Other
Wasting syndrome
Encephalopathy
AIDS dementia complex

Question 9

AIDS diagnosis

Answer 9

CD4 count < 200 OR has an AIDS defining illness

Question 10

Nucleoside Reverse Transcriptase Inhibitors (NRTIs)

MOA and toxicities

Answer 10

zidovudine (Retrovir) (AZT)

inhibits reverse transcriptase thus preventing viral DNA from being produced

severe anemia and neutropenia–may need multiple blood transfusions and tx stopped
lactic acidosis in female or obese patients

Question 11

Non-nucleoside Reverse Transcriptase Inhibitors (NNRTIs)

MOA, AE

Answer 11

efavirenz (Sustiva)

Inhibits reverse transcriptase, works directly against the enzyme

rash - 30% develop; if severe, drug should be halted
CNS sxs - take at night to reduce effects

Lots of drug interactions

Question 12

Integrase Inhibitor

Answer 12

raltegravir (Isentress)

Often used when pts have drug resistant HIV, can also dev. resistance to this drug

Well Tolerated

Drug interations (UGT enzyme)

Question 13

Protease Inhibitors

Answer 13

lopinavir/ritonavir (Kaletra)

AE: hyperglycemia, lipdystrophy, hyperlipidemia, bone loss

Drug interactions

Question 14

Fusion Inhibitor

Answer 14

enfuvirtide (Fuzeon)

Blocks entry of HIV into CD4 t-cells

Given SQ BID

injection site rxs, pna, hypersensitivity

no significant drug interactions

Question 15

CCR5 Antagonist

Answer 15

maraviroc (Selzentry)

Blocks entry into CD4 cell that uses the CCR5 to gain access

Black Box Warning: liver injury (preceded with s/sxs of allergic rx

only used in pts who are resistant and must have blood test showing they have the correct strain that uses this method

Monitor liver labs

Drug interactions