HIV

Question 1

How can HIV be spread? (5)

Answer 1

Sexual transmission

Injection drug misuse

Blood products - bodily fluid contact, large blood transfusion etc

Vertical transmission

Organ transplant

Question 2

How do you test for HIV? Point of care testing vs lab

Answer 2

Saliva or blood sample from an individual’s finger is taken - result within minutes

Blood test sent to the lab

Home testing

Question 3

Which type of lymphocyte does HIV infect and destroy?

Answer 3

CD4 T cells

Question 4

The longer you have HIV infection, the more the ….

Answer 4

CD4 lymphocyte population drops and HIV viral load increases.

As the CD4 count drops your risk of infection/ tumour formation becomes higher (reduced immunity)

Question 5

At what CD4 count are most AIDS diagnoses (severe infections) made?

Answer 5

CD4 <200

Question 6

Describe clinical stage 1 of HIV?

Answer 6

Asymptomatic

Persistent generalised lymphadenopathy

Normal activity levels

This stage can be prolonged - 5-8 years on average

Question 7

Can you recover from stage 4 of HIV?

Answer 7

Yes, nowadays you can present with stage 4 and be asymptomatic within 6 months of anti-viral treatment

Question 8

HIV vs AIDs - how can you tell?

Answer 8

If you have no symptoms then you have HIV infection only

Certain infections and tumours that develop due to a weakness in the immune system are classified as AIDS illnesses. However, virtually everyone with an AIDS illness should recover from it and then be put on antivirals to keep them free from any future illness.

Question 9

Natural history of HIV

Answer 9

Acute infection - seroconversion

Asymptomatic

HIV related illnesses

AIDS defining illness

Death

Question 10

What is seroconversion?

Answer 10

This happens when you are first exposed to the HIV infection.

Within 2-3 weeks your body produces antibodies to it and seroconversion occurs when the antibody and antigen meet.

This results in a group of non-specific symptoms

Question 11

Symptoms of seroconversion

Answer 11

Flu-like illness 
Fever over a couple weeks
Malaise and lethargy 
Pharyngitis
Lymphadenopathy 
Toxic exanthema

It presents like glandular fever but if you don’t have +ve EBV serology then it can’t be and you should think HIV.

Question 12

What is the most common late stage infection associated with HIV/AIDS?

Answer 12

Pneumocystis jiroveci pneumonia

Classical history of dry cough and increasing breathlessness over several weeks

Question 13

How many tablets does an HIV patient have to take in a day?

Answer 13

1 tablet - 3 drugs in 1

for the rest of their life

Question 14

Why do you need a combination of at least 3 drugs from 2 different groups?

Answer 14

Different classes of drugs act on different stages in HIV life-cycle.

Question 15

What are some side effects associated with combination antiretroviral therapy?

Answer 15

Lipodystrophy

Metabolic

Question 16

Look

Answer 16

Reverse transcription inhibitors – inhibit viral RNA from being transcribed into DNA (earliest target developed)

Integrase inhibitors – prevent viral DNA being integrated into host genome

Protease inhibitors – prevent maturation of virus

Question 17

At what part of the pregnancy is HIV transferred from mother to child?

Answer 17

At delivery

Question 18

What is resistance testing?

Answer 18

Look at the genetic code of the HIV virus in your blood to see if there any mutations that are known to cause drug resistance

Can avoid the use of certain drugs to prevent failure of treatment

Question 19

What happens if there is poor adherence to HIV treatment?

Answer 19

If the virus in the body is only exposed to low levels of antiviral drugs then this is not enough to suppress the virus. Instead, this allows the viruses in the body to mutate and become resistant to the low level of drugs.

Failure of treatment^

Question 20

Give examples of some antiviral drug classes

Answer 20

Nucleoside reverse transcriptase inhibitors

Non-nucleoside reverse transcriptase inhibitors

Protease inhibitors

Integrase inhibitors

Question 21

Look

Answer 21

If viral load is undetectable in blood = untransmissible by any means

Question 22

What treatment can be given to those at high risk of contracting HIV infection?

Answer 22

Pre-exposure prophylaxis (PrEP) for those at high risk (sex or injection drugs misuse)

The drug can block HIV if it gets into your body

Question 23

Look

Answer 23

Early treatment is key for good prognosis - Nowadays start all patients at diagnosis regardless of CD4 and viral load – only delay starting if concerned about an immune reconstitution illness e.g. cryptococcal meningitis

Good adherence is needed

Treatment is probably best form of prevention