HIV

Question 1

diagnosis of HIV

Answer 1

serum antibody detection
- HIV enzyme immunoassay antibody tests 
- western blot 
HIV RNA detection/quantification (viral load)
- PCR

Question 2

presentation of HIV

Answer 2

acute HIV infection, lasts 2-3w
asymptomatic phase, lasts for many years
persistent generalised lymphadenopathy, lasts more than 3m
AIDS and related conditions

Question 3

HIV viral load measurement

Answer 3

before initiation of therapy 
within 2-4w, no later than 8w 
every 4-8w until viral load suppressed 
viral suppression by 8-24w 
every 3-6m after stable regimen and suppressed viral load

Question 4

nucleoside reverse transcriptase inhibitors (NRTI)

Answer 4

tenofovir 
emtricitabine 
abacavir
lamivudine 
zidovudine

Question 5

NRTI advantages

Answer 5

established dual backbone combination ART

Renal elimination, little concerns for drug interactions

Question 6

NRTI class disadvantages

Answer 6

adverse effects related to mitochondrial toxicity
- lactic acidosis and hepatic steatosis
- lipoatrophy
- zidovudine > tenofovir = abacavir = lamivudine
requires dose adjustment in renal impaired patients except abacavir

Question 7

integrase strand transfer inhibitor (INSTI)

Answer 7

bictegravir
dolutegravir
raltegravir
elvitegravir

Question 8

NRTI adverse effects

Answer 8

tenofovir - renal impairment, decrease bone mineral density
abacavir - contraindicated in HLA-B*5701, CVS risk patients
zidovudine - myopathy, bone marrow suppression

Question 9

INSTI advantages

Answer 9

high genetic barrier to resistance

well tolerated

Question 10

INSTI disadvantages

Answer 10

weight gain, NV, HA
depression with suicidality with preexisting psychiatric conditions
Foral lowered w concurrent administration of polyvalent cations
Bictegravir, dolutagravir, elvitegravir are CYP3A4 substrates

Question 11

INSTI adverse effects

Answer 11

bictegravir - increase in serum creatinine
raltegravir - pyrexia, creatinine kinase elevation
dolutegravir - increase in serum creatinine

Question 12

non-nucleoside reverse transcriptase inhibitors (NNRTIs)

Answer 12

efavirenz

rilpivirine

Question 13

NNRTI class advantages

Answer 13

long half lives

less metabolic toxicity

Question 14

NNRTI disadvantages

Answer 14

low genetic barrier to resistance 
cross resistance among approved NNRTI 
skin rash, SJS 
potential for CYP450 drug interactions 
QTc prolongation

Question 15

NNRTI adverse effects

Answer 15

efavirenz - rash, HLD, neuropsychiatric SE, hepatotoxicity

rilpivirine - depression, HA

Question 16

protease inhibitors (PI)

Answer 16

ritonavir 
lopinavir 
atazanavir 
darunavir 
fosamprenavir

Question 17

PI advantages

Answer 17

high genetic barrier to resistance

PI resistance less common

Question 18

PI class disadvantages

Answer 18

metabolic complications 
GIT SE 
liver toxicity 
CYP3A4 inhibitors and substrates 
Lipohypertrophy 
increased risk of osteopenia/osteoporosis

Question 19

PI SE

Answer 19

ritonavir: paresthesia, taste perversion
darunavir: skin rash, SJS
atazanavir: CI concurrent use with PPIs, hyperbilirubinemia, prolonged QT interval, skin rash

Question 20

fusion inhibitor and SE

Answer 20

enfuvirtide SC BD

injection site reactions, hypersensitivity reactions, increased bacterial pneumonia

Question 21

CCR5 antagonists

Answer 21

maraviroc
only used in people whose strain of HIV uses CCR5 receptor to enter CD4 cells
SE: abdominal pain, cough, dizziness, musculoskeletal symptoms, pyrexia, rash, URTI, hepatotoxicity, orthostatic hypotension

Question 22

recommended combinations for patients naive to ART

Answer 22

tenofovir + emtricitabine + bictegravir
tenofovir + emtricitabine + dolutegravir
abacavir + lamivudine + dolutegravir