HIV

Question 1

What type of virus is HIV?

Answer 1

RNA retrovirus

Question 2

Describe the different types of HIV

Answer 2

HIV1 - group M responsible from the global epidemic

HIV2 - localised to west Africa, few cases in the UK

Question 3

When does replication occur in HIV?

Answer 3

Very late and very early infection - new generation every 6-12 hours

Question 4

What cells are infected in HIV?

Answer 4

CD4+ cells in the mucosal tissue then transfers into the blood stream via lymphatic drainage

Question 5

How soon is infection established in the body?

Answer 5

72 hours

Question 6

What is the target site for HIV?

Answer 6

T helper lymphocytes

Question 7

State the four functions of T helper lymphocytes

Answer 7

• recognise MHC2 antigen presenting cells
• activate B cells
• activate cytotoxic T cells
• cytokine release

Question 8

How does HIV alter immune system?

Answer 8

Reduced circulation and proliferation of CD4+ T cells
Reduced CD8+ T cells
Reduced antibody affinity
Chronic immune activation (microbial translocation -GALT)

Question 9

What is normal CD4 T cell count?

Answer 9

500-1600 cells/mm3

Question 10

At what CD4 T cell level is there the highest risk fo opportunistic infections?

Answer 10

<200 cells/mm3

Question 11

What are the four key stages in HIV infection?

Answer 11

Primary
Asymptomatic
Symptomatic
AIDS

Question 12

With no treatment how long does HIV take to progress from primary to AIDS?

Answer 12

9-11 years

Question 13

How many people present with HIV primary infection?

Answer 13

80%, 2-4 weeks after infection

Question 14

How does primary HIV present?

Answer 14

Fever, maculopapular rash, myalgia, pharyngitis, headache, aseptic meningitis

Question 15

What happens in the asymptomatic phase?

Answer 15

Ongoing viral replication, CD4 depletion, immune activation and risk of onward transmission

Question 16

Define opportunistic infections

Answer 16

An infection that pathogen does not normally cause disease in a healthy individual

Question 17

What infection can HIV cause in the lungs?

Answer 17

Pneumocystic Pneumonia

Question 18

When does PCP occur and what are the signs/symptoms?

Answer 18

CD4 <200
Symptoms - insidious onset, SOB, dry cough
Signs - exercise oxygen desaturation (pulse up and oxygen down fast)

Question 19

What will a CXR of PCP show?

Answer 19

Normal, interstitial infiltrates, reticulonodular markings

Question 20

How is PCP diagnosed?

Answer 20

Broncho-alveolar lavage, PCR/immunoflorescence

Question 21

How is PCP treatment?

Answer 21

High dose co-trimoxazole

Question 22

What types of TB are more common in HIV positive patients?

Answer 22

Symptomatic primary infection, reactivation of latent TB, lymphadenopathies, miliary TB, extra pulmonary TB, multi-drug resistant, immune reconstitution syndrome

Question 23

What organism causes cerebral toxoplasmosis?

Answer 23

Toxoplasma gondii

Question 24

At what CD4 count can cerebral toxoplasmosis occur?

Answer 24

<150

Question 25

What can reactivation of toxoplasma gondii cause?

Answer 25

Cerebral abscess | Chorioretinitis

Question 26

How will cerebral toxoplasmosis present?

Answer 26

Headache, fever, seizures, focal neurology, reduced consciousness, raised ICP

Question 27

What will a CT of toxoplasmosis show?

Answer 27

Multiple ring enhancing lesions

Question 28

At what CD4 count can cytomegalovirus occur?

Answer 28

<50

Question 29

What screening is done for CMV?

Answer 29

Ophthalmic screening

Question 30

Name the consequences of reactivated CMV

Answer 30

Retinitis Colitis Oesophagus

Question 31

How does reactivation of CMV present?

Answer 31

Reduced visual acuity, floaters, abdominal pain, PR bleeding can lead to blindness

Question 32

How can HIV associated neurocognitive impairment present?

Answer 32

Reduced short term memory +/- motor dysfunction

Question 33

How will neurocognitive HIV impairment appear on CT?

Answer 33

Enlarged ventricles - signs of atrophy

Question 34

What can JC virus reactivation cause?

Answer 34

Progressive multifocal leukoencephalopathy

Question 35

At what level of CD4 will PML present and how will it present?

Answer 35

<100 Rapidly progressing, focal neurology, confusion, personality change MS type picture

Question 36

Name three skin infections HIV can increase your chance of getting

Answer 36

- herpes zoster (multidermatomal/recurrent) - herpes simplex (extensive, treatment resistant) - HPV (chance of dysplasia)

Question 37

What can cause HIV associated wasting?

Answer 37

``` Metabolic immune activation Anorexia Malabsorption HIV enteropathy Hypogonadism ```

Question 38

What tumour can herpes virus 8 cause?

Answer 38

Kaposi's Sarcoma - vascular tumour

Question 39

How will kaposi's sarcoma present?

Answer 39

Cutaneous, mucosal, visceral (pulmonary, GI)

Question 40

How is kaposi's sarcoma treated?

Answer 40

Anti-retroviral, local therapies, systemic chemo

Question 41

What haematological malignancy can HIV cause?

Answer 41

Non-Hodgkins lymphoma

Question 42

When can non-AIDS symptomatic HIV occur?

Answer 42

During asymptomatic phase

Question 43

State factors that increase transmission of HIV

Answer 43

Anoreceptive sex Trauma Genital ulceration Concurrent STI

Question 44

Why is the rectum more easy to transmit HIV compared to the vagina?

Answer 44

It is only 1 cell thick and has lots of lymphoid tissue

Question 45

Name three ways HIV can be transmitted

Answer 45

Parenteral | Mother to child

Question 46

How can HIV be transmitted parenterally?

Answer 46

Injection drug use Infected blood produced Iatrogenic

Question 47

How can HIV be transmitted from mother to child ?

Answer 47

In utero Delivery Breast feeding

Question 48

Where is HIV a pandemic?

Answer 48

Sub Saharan Africa Caribbean South East Asia

Question 49

Where is HIV an epidemic ?

Answer 49

Russia | Eastern Europe

Question 50

What percentage of people are misdiagnosed in the UK?

Answer 50

6%

Question 51

Name four testing techniques for HIV testing

Answer 51

Universal testing Opt-out testing Screening high risk groups Testing on clinical grounds

Question 52

Name high risk groups

Answer 52

``` MSM Female partners MSM Black Africans Prisoners Trans women PWID Partners of people living with HIV Endemic areas ```

Question 53

Name blood markers measured in HIV

Answer 53

- antibodies (3 months to become detectable) - antigen - p24 - viral RNA

Question 54

Describe a rapid HIV test

Answer 54

Fingerpick blood specimen/saliva get results in 20-30 minutes measures both the antibody and antigen

Question 55

What prophylaxis treatment can be given for PCP?

Answer 55

Co-trimoxazole 480mg daily

Question 56

Name four targets of HIV treatment

Answer 56

Reverse transcriptase Integrase Protease Entry to cell - fusion or CC5R receptor

Question 57

Define highly active anti-retroviral

Answer 57

A combination of 3 drugs from at least 2 classes to which the virus is susceptible

Question 58

How does drug resistance occur?

Answer 58

Mutations can occur in low compliance leading to resistance

Question 59

What does U=U mean?

Answer 59

Undetectable = untransmitable

Question 60

What side effects can occur from anti-retroviral treatment?

Answer 60

``` GI side effects Skin - rash, hypersensitivity, SJS CNS - mood, psychosis Renal complications Osteomalacia CVD Haematological complications ```

Question 61

Describe pre-exposure prophylaxis

Answer 61

2 drugs to prevent acquiring HIV in high risk individuals | - tenofovir and emtricitabine daily or on demand

Question 62

What are the side effects of PrEP

Answer 62

Renal health can be affected Drug-drug interactions Requires regular monitoring

Question 63

Describe post exposure prophylaxis

Answer 63

72 hours within high risk exposure | Prep and rategravir for 4 weeks

Question 64

In pregnant women if the viral load is detectable what form of delivery is required?

Answer 64

C section

Question 65

How long should PEP be given in a neonate?

Answer 65

2-4/52