HIV/AIDS Flashcards
what kind of virus?
retrovirus
what are the target sites for HIV?
CD4
what is CD4? where is it found?
a glycoprotein, found on surface of cells
which cell types is it found on?
T helper lymphocytes, dendritic macrophages, macrophages, microglial cells
what do helper t cells do?
recognise MCH2 antigen presenting cells, activate B cells (antibodies), activate cytotoxic t cells (killer T), cytokine release
if you have HIV infection, what happens to numbers of helper T cells?
reduced, you get a decreased proliferation of helper t cells
why do you get a reduction in antibodies?
HIV attacks helper T cells, which activate B cells, which produce antibodies
If you have HIV, you have a susceptibility to ?
viral infections, fungal infections, mycobacterial infections, infection induced cancers
what is the normal value of helper t cells?
500-1600
risk of opportunistic infection if below?
200
when do you get rapid replication of the virus
very early and very late stages of the infection, with a new generation every 6-12 hours
which cells do HIV actually infect?
mucosal CD4 cells
when is the infection established?
within 3 days of entry
2-4 weeks after the infection, what sort of symptoms would you expect?
fever, rash, myalgia, pharyngitis, headache. ACUTE HIV SYNDROME
after 3 weeks, your virus level is high and CD4 levels are down to about half
y
what happens in-between acute HIV syndrome and symptoms of AIDS?
asymptomatic period
how do you treat pneumocystis pneumonia?
co-trimoxazole
what kind of cancer can you get in AIDS?
kaposi’s sarcoma
what accounts for 94% of transmission?
sex
how else could you get it?
drug injectors
how can HIV spread from mother to child?
in utero, at delivery, breastfeeding
HIV virus binds to CD4 receptor and one co receptor, what are these?
CCR5, CXCR4
what is the enzyme that makes double standed DNA from single?
reverse transcriptase
what enzyme integrates viral DNA into the host?
integrase
transcription then occurs, long chains of proteins are made, immature virus pushes out of cell. buds off taking cell membrane with it
y
what enzyme processes proteins in newly forming virus?
proteases
what does the protease enzyme finish?
cutting HIV protein chains into individual proteins to make a NEW WOKRING VIRUS
what is an NRTI?
reverse transcriptase inhibitor
example of this drug?
retrovir
generally, protease inhibitors and NRTIs are ?
potent liver enzyme inhibitors
what is the definition of highly active anti retro viral therapy?
a combination of 3 drugs from at least 2 drug classes to which the virus is suceptible
single best co formulation?
EF LA TE - efavirenz, lamivudine, tenovir
what term describes a relationship where one partner is hiv positive and other is negative?
serodiscordant
what is sperm washing?
individual sperm separated from semen
what is HAART?
customised combination of medications that a physician prescribes based on viral load/strain etc
what can you get from this though?
HAART toxicity, GI effects, bone CVS, haematology, renal toxicity
another way to conceive?
timed unprotected sex with HAART
how do you prevent mother to child transmission during pregnancy?
HAART
when would you do a vaginal delivery?
when there is an undetectable load
when would you do a CS?
when there is a detectable viral load
a woman has been exposed to chlamydia infection last week, what do you do?
start treatment - starts on exposure o the infection, not proven infection
if you suspected there was not enough progesterone, and this was causing infertility, when would you check progesterone levels?
day 21
