HIV

Question 1

Name 2 suitable host cells of HIV infection? Why?

Answer 1

CD4+ T lymphocytes and macrophages

They have the correct CD4 receptors on the surface

Question 2

When the viral nucelocapsid enters the host cell and breaks down what does it release?

Answer 2

3 essential replication enzymes
Integrase
Portease
Reverse transcriptase

Question 3

Function of integrase?

Answer 3

Transfers viral DNA into cell nucleus and facilitates integration into host genome

Question 4

Function of reverse transcriptase?

Answer 4

Reverse transcription of viral RNA to DS DNA

Question 5

List 4 points HIV treatment can block the replication pathway

Answer 5

Fusion inhibitors block entry to host cell
Nucleoside inhibitors of non-nucleoside reverse transcriptase inhibitors inhibit reverse transcription
Integrase inhibitors inhibit integration of viral genome into host
Protease inhibitors

Question 6

Describe CD4 levels after primary infection?

Answer 6

Rapid decrease then light increase as the HIV isn’t established yet, followed by a slow decrease over time

Question 7

Consequences of reduced CD4 count?

Answer 7

Increased risk fo atypical/recurrent/prolonged infections
Increased risk of AIDs related cancers
Increased risk fo organ specific HIV related complications

Question 8

Consequences of increase in viral load?

Answer 8

CD4 count falls, HIV related conditions increase and a infectivity increases

Question 9

Describe symptoms in clinical stage I of HIV infection?

Answer 9

Asymptomatic

Swelling of lymph nodes (persistent generalised lymphadenopathy)

Question 10

Describe symptoms in clinical stage II of HIV infection?

Answer 10

Weight loss, less than 10%
Angular chelitis (other minor mucocutaneous manifestations)
Herpes Zoster
Recurrent upper respiratory infections

Question 11

Describe symptoms in clinical stage III of HIV infection?

Answer 11

Weight loss, more than 10% 
Oral hairy leukoplakia
Oral candidiasis 
TB
Severe bacterial infections

Question 12

Describe symptoms in clinical stage IV of HIV infection?

Answer 12

Karposi’s sarcoma
HIV encephalitis
HSV
Candaiasis of lungs

Question 13

What category of people tend to receive late diagnosis, why?

Answer 13

Heterosexual men living outside of London.

They aren’t educated, not enough testing

Question 14

List 5 routes of acquisition of HIV?

Answer 14

Sexual intercourse
Iv drug use
Mother to child transmission
Infected blood products
Occupational

Question 15

How to reduce sexual transmission of HIV?

Answer 15

Condoms, PREP (PEP)= pre-exposure prophylaxis = 2 drugs given before exposure

Question 16

How to reduce mother to child transmission of HIV?

Answer 16

Avoid breastfeeding
Decrease mothers viral load below 100
PEP for baby

Question 17

List 5 disease that should indicate a HIV test is required?

Answer 17

TB
Bacterial pneumonia
Encephalitis
Kaposi's sarcoma
Herpes Zoster
Oral hairy leukoplakia
Weight loss
Hep B infection
Neutropenia

Question 18

When should treatment start?

Answer 18

As soon as diagnosed - do not wait for CD4 count to get low

Question 19

Why should treatment be started as soon as possible?

Answer 19

Less AIDs related complications
Reduce all cause mortality
Reduced transmission

Question 20

What is of note of the kind of drugs given to treat HIV?

Answer 20

At least 3 different drugs of at least 2 different classes - better barrier - targets more steps so more likely to be effective

Question 21

What is HAART?

What are the aims of HAART?

Answer 21

Highly active anti-viral therapy
Inhibit viral replication
Present high genetic barrier to resistance (3+ drugs 2+ classes)
Allow Cd4 count to recover

Question 22

List the possible targets for HAART?

Answer 22

Cell entry - co-receptor antagonism, fusion inhibitor

Enzyme inhibitor - reverse transcriptase inhibitor, integrase inhibitor, protease inhibitor

Question 23

List 8 issues in HIV care

Answer 23

Late diagnosis
Stigma
Adherence to drug regime
Interactions
Partner notification and testing
Prevention of transmission 
Management of co-morbitiies
Conception and pregnancy planning