HIV

Question 1

what is HIV?

Answer 1

RNA retrovirus

Question 2

which type of HIV is responsible for the global epidemic?

Answer 2

HIV-1 group M

Question 3

life cycle of HIV

Answer 3

• Two strands of RNA with GP120 and GP41 antigens that bind to Th cells CD4+ receptor
• RNA enters the cell and is converted to DNA and integrated into the host cell
• Creates viral proteins and assembles another virus every 6-12 hour

Question 4

how long does it take HIV to establish infection?

Answer 4

within 3 days of entry so 72 hours for PEPSE

Question 5

where is the CD4+ receptor found?

Answer 5

Th cells
dendrites
macrophages
microglia

Question 6

what is the CD4+ receptor essential in?

Answer 6

recognition of MHC-II APCs
activation of B cells
activation of Tc (CD8+) with cytokine release

Question 7

what is a normal CD4+ count?

Answer 7

500-1,600 cells/mm3

Question 8

what CD4+ count is there a high risk of opportunistic infections?

Answer 8

<200 cells/mm3

Question 9

presentation of primary HIV

Answer 9

2-4 weeks later
fever
rash (maculopapular)
myalgia
pharyngitis
headache
aseptic meningitis
can be asymptomatic

Question 10

what is the risk in primary HIV?

Answer 10

very high risk of transmission

Question 11

what is late stage HIV?

Answer 11

AIDS

Question 12

describe the cascade to AIDs?

Answer 12

HIV > immunosuppression > opportunistic infections/ cancer > AIDs

Question 13

at risk groups

Answer 13

MSM
heterosexuals aged 15-44
black African
PWIDs

Question 14

diagnosis

Answer 14

viral RNA, antigen p 24 or antibody

rapid= finger prick or saliva (20-30 minutes)

Question 15

why can you not reply on a negative Ab in first 6 weeks?

Answer 15

3 month window period (different people make Ab at different rates)

Question 16

management of HIV

Answer 16

start therapy at all CD4 counts
HAART= combination of 3 drugs from at least 2 drug classes
partner notification

Question 17

side effects of HAART

Answer 17

GI
drug interactions
co-infections
polypharmacy

Question 18

management of HIV in pregnancy

Answer 18

C/S

vaginal birth if undetectable load

Question 19

prevention of neonatal HIV

Answer 19

zidovudine infusion given 4 hours prior to C/S

Question 20

prevention methods

Answer 20

condoms
regular testing
PrEP
PEP
ART
needle exchange
neonate prophylaxis

Question 21

what is PEP consist of?

Answer 21

4 weeks of tenofovir/ emtricitabcine and raltegravir

Question 22

examples of opportunistic infections

Answer 22

1. pneumocystis pneumonia (PCP)
2. TB
3. cerebral toxoplasmosis
4. CMV
5. HIV dementia
6. prgressive multifocal leukoencephalopathy (PML)
7. skin infections that are recurrent, extensive and resistant
8. Slim’s disease
9. cancers

Question 23

what causes PCP?

Answer 23

pneumocystitis jiroveci

Question 24

presentation of PCP

Answer 24

SOB
dry cough
CD4 <200

Question 25

diagnosis of PCP

Answer 25

CXR
BAL
immunofluorescence +/- PCR

Question 26

management of PCP

Answer 26

co-trimoxazole

Question 27

what causes cerebral toxoplasmosis?

Answer 27

toxoplasma gondii

Question 28

what is cerebral toxoplasmosis?

Answer 28

reactivation of latent infection produces cerebral abscesses and chorioretinitis

Question 29

presentation of cerebral toxoplasmosis

Answer 29

headache
fever
focal neurology
seizures
reduced consciousness
raised ICP
CD4 <150

Question 30

presentation of CMV

Answer 30

reduced visual acuity
floaters
abdominal pain
PR bleeding
CD4 <50

Question 31

when is ophthalmic screening carried out?

Answer 31

all those with CD4 <50

Question 32

what causes progressive multifocal leukoencephalopathy PML?

Answer 32

JC virus

Question 33

presentation of PML?

Answer 33

CD4 <100
rapidly progressive focal neurology
confusion
personality change
MS-type picture

Question 34

what is Slim’s disease?

Answer 34

HIV-related cachexia

Question 35

which cancers are related to AIDS?

Answer 35

Kaposi’s sarcoma (HHV8)
NHL (EBV)
cervical cancer (HPV)