HIV

Question 1

aetiology

Answer 1

women children SSA
MSM in UK
predominantly: HIV 1 group B

tranmission 75% sexual - others IVDU, blood transfusions, tattoos, organ transplant

Question 2

pathology

Answer 2

RNA retrovirus - infects CD4 expressed cells binds to gp 120: DNA -> RNA - destruction: CD4+ helper T cells, macrophages, monocytes, neutrophils.
Reduced efficacy of host immune system

Viral
AIDS = CD4 <200

Question 3

CD4 count cut offs

Answer 3

Anteretrovirals <350

AIDS <200

Question 4

PC of HIV

Answer 4

weight loss, lymphadenopathy, thrust, oral and skin disease

like glandular fever

Question 5

HIV viral load - disease progression

Answer 5

initially high - window stage: highly infectious

then falls

rises again in later stages

Question 6

chemokine receptor relatively resistant to HIV

Answer 6

CCR-5

Question 7

combination antiretroviral therapy (cART) Aim?

Answer 7

reduce viral load to undetectable levels - so can’t transmit infection

Question 8

cART regime

drug classes + SEs

Answer 8

3 drugs from 2 classes:
-nucleoside reverse transcriptase inhibitors (AZT)
marrow toxicity

• non nucleoside reverse transcriptase inhibitors
  nightmares
• protease inhibitors: premature vascular disease

Question 9

treatment failure?

Answer 9

test for resistance and change therapy - especially if intolerable side effects - lipodystrophy

Question 10

stages?

Answer 10

1. asymp, persistant generalised lymphadenopathy
2. early/mild disease: <10% weight loss, recurrent URTIs, seb derm
3. moderate: >10% weight loss, unexplained - chronic diarrhoea, persistent fever, anaemia
4. late - AIDS,