HIV Flashcards
pre-exposure prophylaxis (PrEP) eligibility
MSM condomless anal sex with 2+ partners in last year + likely in next 3months
rectal bacterial STI in last year
ongoing sexual contact with someone with HIV VL >50
OR 2 sexxual health clinicians agree similar risk above
post exposure prophylaxis hep B
HBV vaccine booster - within 7 days
Immunoglobulin - for vaccine non-responders
HIV post exposure prophylaxis
3 antiretrovirals for 28days (4wks)
start within 72hrs
testing at 12weeks following completion
80% reduced risk of transmission
management of non-consensual sex
recent <7days
- immediate safety
- forensic if appropriate/wished
- PEPSE for HBV (+HIV) if appropriate)
- Mx physical injuries, STI + contraceptive care as needed
later >7days
- safeguarding
- HBV if within 6wks
- assess coping / ongoing psychological impact
**autonomy important
HIV vs AIDs
AIDs = acquired immunodeficiency syndrome - late stage of HIV
- occurs as person becomes immunodeficient
- leads to opportunistic infections + AIDS definign illnesses
HIV types
HIV-1 = commonest
HIV-2 = rare outside of west africa
takes up to 72hrs from exposure to establish itself as an infection
after infection is established there is rapid replication + dissemination of virus to reservoir sites
transmission of HIV
oral, anal, vaginal sex - 79%
(factors increasing transmission - anoreceptive sex, trauma, genital ulceration, concurrent STI)
mother to child at any stage of pregnancy, birth, or breastfeeding
muscous membrane, blood or open wound exposure to infected blood/bodily fluids
- sharing needles, blood splashed in eye
pathophysio of HIV
RNA retrovirus
virus enters + destroys CD4 T-helper cells of immune system (langerhans + dendritis)
- transport to regional lymph nodes
- infection established within 3 days of entry
- dissemination of vieus
initial seroconversion flu-like illness within 2-4wks of infection
then infection asymptomatic until condition progresses to immune deficiency
rapid replication in very early + very late infection - new generation every 6-12hrs
effect of HIV on immune response
reduce circulating CD4
reduce proliferation of CD4
reduce CD8 cytotoxic activation - dysregulated expression of cytokines
reduction in antibody class switching - reduce affinity of antibodies produced
chronic immune activation
–> all increase susceptibility to infections
CD4 parameters
normal = 500-1600
highest risk of opportunistic infections = <200
HIV screening
many dont know, high risk should be tested
can take up to 3month to develop antibodies - test can be neg in this time
**patients need consent for test
at risk = MSM, female partner of MSM, black africans, prisoners, trans women, PWID, partners of people living with HIV, Sub-Saharan Africa, Caribbean, Thailand, sexual partners, children iatrogenic exposure from these/other endemic areas
taking an HIV test
document consent or refusal
obtain venous sample for serology
if incapacitated
- only test if in patients best interest
- consent from relative not required
- if safe - wait till regains capacity
mode of delivery in HIV positive mums
vagina if viral load <50 copies/ml at 36weeks
–> other wise C-section
NEVER breastfeed
HIV seroconversion
typically occurs 3-12weeks after infection
increased symptomatic severity assoc with poorer long term prognosis
presents as glandular fever type illness
- sore throat
- lymphadenopathy
- diarrhoea
- maculopapular rash
- mouth ulcers
screening + diagnostic test for HIV
Combination test of -
1. Antibodies to HIV may not be seen
* Most people develop by 4-6wks but 99% by 3months
2. HIV PCR + p24 antigen can confirm diagnosis
* A viral core protein that appears early in the blood as the viral RNA levels rise
–>if positive should be repeated to confirm diagnosis
