HIV

Question 1

What type of virus is HIV

Answer 1

Single stranded enveloped RNA virus (retrovirus)
Family: retroviridae
Genus: Lentivirus

Question 2

Two types of HIV

Answer 2

HIV-1 (most common), HIV-2 (West Africa, more indolent, less vertical transmission, intrinsic resistance)

Question 3

How does HIV cause disease

Answer 3

Destroys CD4 helper lymphocytes, creating acquired immunodeficiency

Question 4

Most common mode of transmission of HIV in paediatrics

Answer 4

Vertical transmission (Mother to baby), highest risk of transmission is intrapartum

Question 5

HIV clinical presentation

Answer 5

FTT, unexplained prolonged fever, chronic diarrhoea, opportunistic infections, lymphadenopathy, splenomegaly, persistent oral/napkin candidiasis

Question 6

Acute retroviral syndrome

Answer 6

Adolescents; fever, malaise, lymphadenopathy, rash 7 - 14 days post infection (Glandular fever type illness)

Question 7

Laboratory criteria for HIV diagnosis <18 months

Answer 7

Positive HIV NAT, HIV DNA or HIV RNA. x2 positive tests. Serology not useful, as maternal antibodies transfer

Question 8

Laboratory criteria for HIV diagnosis >18 months

Answer 8

Positive HIV antigen/antibody test (fourth generation tests) which can detect HIV-1/HIV-2 Ab and HIV-1 p24 antigen (can be detected as early as 10 - 14 days after infection. PLUS positive on different supplemental test (Western blot, HIV-1/2 differentiation immunoassay)

Question 9

CAR T-Cell therapy and HIV

Answer 9

HIV tests can be false positive in patients who have had this, as same lentivirus can be used as viral vector for CAR T-Cell

Question 10

Four main ART classes

Answer 10

NRTI (Nucleoside Reverse Transcriptase Inhibitor) NNRT (Non Nucleoside Reverse Transcriptase Inhibitor), ISTI (Integrase Inhibitor), PI (Protease Inhibitor)

Question 11

Treatment for Paediatric HIV

Answer 11

2 NRTIs + third drug (NNRTI, PI or ISTI) Most evidence from Odyssey Trial for ISTI

Question 12

NRTI examples

Answer 12

Zidovudine, Tenofovir, Lamivudine, Abacavir

Question 13

NNRTI examples

Answer 13

Nevirapine

Question 14

ISTI examples

Answer 14

Raltegravir, Dolutegravir

Question 15

PI examples

Answer 15

Lopinavir/Ritonavir, Atazanavir

Question 16

Side effects of NRTI

Answer 16

Lactic acidosis, mitochondrial toxicity, Zidovudine causes anaemia, and Tenofovir causes renal tubular dysfunction. Abacavir has hypersensitivity with HLA B5701

Question 17

Side effects of NNRTI

Answer 17

Rash, hepatitis, SJS within 6 weeks

Question 18

Side effects of PI

Answer 18

Lipodystrophy, hyperlipidemia, diabetes CYP3A4 metabolism (drug interactions)

Question 19

Side effects of INSTI

Answer 19

Insomnia, mood changes

Question 20

What percentage of HIV in kids is acquired through vertical transmission?

Answer 20

95%

Question 21

What is the risk of HIV vertical transmission without intervention?

Answer 21

25 - 45%

Question 22

When is highest risk of vertical transmission and what percentage?

Answer 22

60-70%, at delivery

Question 23

Maternal risk factors for vertical transmission

Answer 23

High viral load, low CD4 count, STIs, placental infection

Question 24

Delivery risks for vertical transmission

Answer 24

Prematurity, LBW. PROM. vaginal birth assisted delivery, episiotomy, ARM, chorio

Question 25

What is the risk of infection in utero?

Answer 25

30 - 40%

Question 26

What intrapartum interventions can be instituted if high maternal viral load at 36 weeks?

Answer 26

Intrapartum antivirals, elective caesarean at 38 - 39 weeks gestation

Question 27

What type of feeding recommended for HIV positive mothers

Answer 27

Formula/donor EBM. RIsk of breast feeding transmission 5 - 20%, and with good ART suppression and supported breastfeeding reduces to <1% but not zero

Question 28

Risk factors for post partum transmission

Answer 28

Detectable viral load, longer feeding, mixed feeding, neonatal mouth or breast inflammation

Question 29

Neonatal post exposure prophylaxis

Answer 29

Commenced <4 hours after birth, 2 weeks for very low risk, 4 weeks for low to high risk

Question 30

When to start PCP prophylaxis

Answer 30

HIV PCR positive at any time or infant confirmed to have HIV.

Question 31

What is used for PCP prophylaxis and from what age

Answer 31

Cotrimoxazole, from 1 month age

Question 32

What is U = U

Answer 32

Undetectable = Untransmissible for sexual transmission, but doesn't prevent other STIs so still need to use barrier protection

Question 33

Definition of undetectable viral load

Answer 33

VL <200 copies/mL for >6 months

Question 34

What is PREP

Answer 34

Pre-exposure prophylaxis in high risk, HIV negative populations. Daily ART given to reduced risk of transmission. 90% effective

Question 35

What is nPEP

Answer 35

Non occupational post exposure prophylaxis. Risk of HIV transmission = risk of HIV viraemia in source x exposure activity risk

Question 36

When to start nPEP and duration

Answer 36

Start <72 hours, duration 28 days, then test baseline serology then 3 months

Question 37

Which age group is HIV related mortality rising>

Answer 37

Adolescents. Poorer ART adherence.