HIV physiology and Management

Question 1

What is CD4

Answer 1

A glycoprotein found on the surface of a range of cells.

Question 2

What immune complex cells express CD4 on their surface?

Answer 2

T helper lymphocytes
Dendritic cells
Macrophages
Microglial cells

Question 3

What receptors are a target site for HIV?

Answer 3

CD4+

Question 4

Give 4 actions CD4+ Th lymphocytes carry out

Answer 4

Cytokine release
Activation of B-cells
Activation of cytoxic T cells (CD8+)
Recognition of MHC2 antigen presenting cells

Question 5

What effect does HIV have on immune response?

Answer 5

Reduces circulating CD4+ cells
Reduces proliferation of CD4+
Reduces CD8+ activation
Reduces antibody class switching 
Chronic immune activation

Question 6

What impact does CD8+ reduction have?

Answer 6

There is dysregulated expression of cytokines leading to increased susceptibility of viral infection

Question 7

What 4 categories does an HIV infected individual become susceptible to?

Answer 7

Viral Infection
Fungal Infection
Mycobacterial Infections
Infection-induced cancers

Question 8

What is the normal parameters of CD4+ Th cells?

Answer 8

500-1600 cells/mm3

Question 9

At what level of CD4+ does an individual become at risk to “opportunistic infections”

Answer 9

<200 cells/mm3

Question 10

Define “opportunistic infections”

Answer 10

An infection caused by a pathogen which would not normally produce disease in a healthy individual

Question 11

When does HIV undergo rapid replication?

Answer 11

In the very early and very late stages of infection?

Question 12

What % of patients with primary HIV present with symptoms?

Answer 12

80%

Question 13

What is the average time onset of symptoms post infection

Answer 13

2-4 weeks

Question 14

HIV has high risk of transmission. True/False?

Answer 14

True

Question 15

What type of rash is common in those infected by HIV

Answer 15

Maculopapular

Question 16

What symptoms might someone with HIV present with?

Answer 16

Fever 
Rash
Myalgia 
Pharyngitis 
Headache

Question 17

What is the biggest risk in patients with asymptomatic HIV?

Answer 17

Transmission

Question 18

What pneumonia-causing organism is common in HIV infected patients?

Answer 18

Pneumocystis Jiroveci

Question 19

How do you treat pneumocystis pneumonia?

Answer 19

High dose co-trimoxazole

Question 20

How do you diagnose pneumocystis pneumonia?

Answer 20

BAL and immunofluorescence

Question 21

What X-ray changes may be seen in pneumocystis pneumonia?

Answer 21

Interstitial infiltrates

Reticulonodular markings

Question 22

What is the CD4+ threshold for infection by pneumocystis jiroveci?

Answer 22

<200cells/mm3

Question 23

What is the CD4+ threshold for infection by toxoplasma gondii?

Answer 23

<150cells/mm3

Question 24

What are the symptoms/signs of Cerebral Toxoplasmosis?

Answer 24

Headache
Fever 
focal Neurology
Seizures
Reduced consciousness
Raised ICP

Question 25

What does the organism toxoplasma gondii cause?

Answer 25

Cerebral Toxoplasmosis | reactivation of a latent infection causing multiple cerebral abscesses

Question 26

What virus has a CD4+ threshold of <50cells/mm3

Answer 26

Cytomegalovirus

Question 27

What can CMV cause?

Answer 27

Retinitis Colitis Oesophagitis

Question 28

How does a CMV infection present?

Answer 28

``` Reduced visual acuity Floaters Abdo pain PR bleeding Diarrhoea ```

Question 29

What should be carried out in all patients with a CD4+ <50

Answer 29

Ophthalmic screening

Question 30

What is significant about a Herpes Simplex infection in HIV patients?

Answer 30

Often Aciclovir resistant and extensive Hypertrophic

Question 31

Give 2 abnormal skin infections found in HIV patients?

Answer 31

Penicilliosis | Histoplasmosis

Question 32

Which skin infection common in HIV + patients is known to be dysplastic?

Answer 32

Human Papilloma Virus

Question 33

Which strain of HIV is associated with neurocognitive impairment?

Answer 33

HIV-1

Question 34

What is meant by "slims disease"?

Answer 34

HIV impacts metabolism and absorption which often leads to patients becoming anorexic

Question 35

Give 3 examples of AIDs-related cancers:

Answer 35

Kaposi's Sarcoma Non-Hodgkin's Lymphoma Cervical Cancer

Question 36

What virus is responsible for AIDs related Non-Hodgkin's Lymphoma?

Answer 36

EBV

Question 37

What cancer can HHV8 (herpes virus) cause in HIV patients?

Answer 37

Kaposi's Sarcoma | vascular tumour

Question 38

How many HIV patients suffer from anaemia?

Answer 38

90%

Question 39

What is the main method of HIV transmission?

Answer 39

Sexual Transmission | especially anoreceptive

Question 40

What is the other method of HIV transmission (less common)

Answer 40

Parenteral | Through drug injection and infected blood products

Question 41

What is the risk of mother to baby transmission of HIV if no treatment?

Answer 41

1/4

Question 42

Define highly active anti-retroviral therapy: (HAART)

Answer 42

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

Question 43

Give 4 reasons why we use HAART

Answer 43

Reduce viral load to undetectable level Restore immunocompetence Reduce morbidity/mortality Minimise Toxicity

Question 44

Give an example of a class of HIV drugs?

Answer 44

Nucleoside Analogues Reverse Transcriptase Inhibitors | NRTI

Question 45

What methods of delivery are used with HIV mother?

Answer 45

Vaginal if undetectable viral load | C-section is detectable viral load

Question 46

How long should a neonate be given PEP therapy?

Answer 46

4 weeks Triple load if detectable, 1 drug if undetectable

Question 47

HIV infected mothers can breast feed. True/False

Answer 47

False | Infant must be formula fed only!