HIV

Question 1

Explain the virus structure of HIV?

Answer 1

• RNA retrovirus

- uses reverse transcription

Question 2

How quick is HIV replication?

Answer 2

• very quick in early and late infection

- new generation every 6-12yhours

Question 3

Explain the stages of HIV virus entry into the body?

Answer 3

• binding to the CD4+ cell
• fusion into the cell
• reverse transcriptase
• integration into the cell
• transcription
• translation
• formation of new viral proteins
• new generation every 6-12hrs

Question 4

What cells do HIV virus primarily target?

Answer 4

• CD4+ T cells

T helper cells

Question 5

Explain what happens to an infected CD4+ Cell?

Answer 5

• CD4+ Cell infection
• transported to regional lymph nodes
• infection established within 3 days (72hrs)
• dissemination of virus?

Question 6

Affects on cell levels in HIV?

Answer 6

• Reduced circulating CD4+ Cells
• reduced proliferation of CD4+ cells
• reduced CD8 Cells (initially higher)
• chronic immune activation

Question 7

What is the normal and abnormal levels of CD4+ Cells?

Answer 7

• normal > 500

- bad < 200

Question 8

What is an opportunistic infection?

Answer 8

• infection caused by a pathogen that does not normally produce a disease in a healthy individual

Question 9

What are the 3 stages of HIV infection?

Answer 9

• primary infection
• asymptomatic infection
• symptomatic

Question 10

What are the symptoms often displayed in the primary infection phase of HIV?

Answer 10

• Non-specific symptoms

- rash, fever, myalgia, headache

Question 11

What is PCP?

Answer 11

• Pneumocystic pneumonia
• Opportunistic infection
• CD4 <200
• Insidious onset, SOB, Dry cough

Question 12

Investigations of PCP?

Answer 12

• CXR = Interstital infiltrates
• Exercise oxygen desaturation
• bronchoalveolar lavage -> PCR

Question 13

Treatment of PCP?

Answer 13

• Co - trimoxazole

Question 14

Symptoms of cerebral toxoplasmosis?

Answer 14

• CD4 < 150
• Headache, fever, focal neurology
• cerebral oedema

Question 15

How does cerebral toxoplasmosis appear on CT?

Answer 15

• Ring enhancing lesions on brain CT

Question 16

Symptoms of cytomegalovirus?

Answer 16

• CD4 < 50
• Reduced visual acuity
• floaters
• abdo pain
• diarrhoea

Question 17

Symptoms of HIV associated neurocognitive impairment?

Answer 17

• reduced short term memory

- +/- motor dysfunction

Question 18

Name some opportunistic infections associated with HIV?

Answer 18

• Pneumocystic pneumonia
• TB
• Cerebral toxoplasmosis
• cytomegalovirus
• HIV associated neurocognitive impairment
• progressive multifocal leukoencephalopathy

Question 19

Skin infections associated in hIV?

Answer 19

• Herpes zoster
• herpes simples
• HPV

Question 20

Cancers associated with HIV?

Answer 20

• Kaposis sarcoma
• non-hodgkin lymphoma
• cervical cancer

Question 21

Symptoms of HIV - non-AIDS?

Answer 21

• Mucosal candidiasis
• seborrhoeic dermatitis
• diarrhoea
• fatigue
• lymphadenopathy

Question 22

Haematological manifestations of HIV?

Answer 22

• Lymphopenia

- thrombocytopenia

Question 23

Modes of transmission of HIV?

Answer 23

• Sexual transmission
• Parenteral transmission
• Mother-to-child

Question 24

What might increase the transmission of HIV sexually?

Answer 24

• unreceptive sex
• trauma
• genital ulcerations
• concurrent STI

Question 25

When might mother-to-child spread of HIV occur?

Answer 25

- in utero - delivery - breast feeding

Question 26

Testing strategies for HIV?

Answer 26

- Universal screening - opt-out during certain procedures - screening at risk groups - testing on clinical grounds

Question 27

Who are considered high risk groups for HIV?

Answer 27

- MSM - Black Africans - Prisoner's - Trans women - PWID - Partner's of people living with HIV

Question 28

What 3 factors can be tested for in HIV?

Answer 28

- Viral RNA (First to become positive) - Antigen - Antibody (can take 3 months to become positive)

Question 29

What testing is done in Tayside for HIV and what is the window period?

Answer 29

- 4th generation testing (combining antibody and antigen) | - window period = test may be falsely negative in first 45 days

Question 30

What is the anti-retroviral therapy treatment?

Answer 30

- high active antiretroviral therapy (HAART) - 2 X nucleoside reverse transcriptase inhibitor - 1 x another

Question 31

Name different HIV (Anti-retroviral) drug classes?

Answer 31

- Nucleoside reverse transcriptase inhibitor - integrase inhibitor - non-nucleoside reverse transcriptase inhibitor - protease inhibitor - integrase inhibitor

Question 32

Explain PrEP?

Answer 32

- Pre-exposure prophylaxis - 2 tablets either daily or before risk - tenofovir - emtricitabine

Question 33

Explain Post-exposure prophylaxis?

Answer 33

- within 72hrs of risk - 3 drugs taken for 4 weeks - raltegravir - tenofovir - emtricitabine

Question 34

What prevents mother-to-child HIV transmission

Answer 34

- undetectable load = natural delivery - detectable load = caesarean - formula feeding - 2/4 weeks of PEP for neonate

Question 35

Best preventions for HIV?

Answer 35

- Testing - condoms - opioid substitution - raising awareness