HIV Flashcards
How does HIV infect a cell?
HIV binds to CD4 receptors on T helper cells, monocytes and macrophages
These CD4 cells migrate to lymphoid tissue to replicate and infect new cells
This depletes and impairs CD4 cells until immune dysfunction occur
What is HIV?
Human immunodeficiency virus
A retrovirus
At what CD4 count does AIDS occur?
CD4 count of <200
Who should be tested for HIV!
All patients with an STI
Anyone registered at a GP where the prevalence in local population exceeds 1/500
Anyone who has had sexual contact with people from Africa, Far East, Caribbean
All sexual partners of known HIV+ people
Men who have sex with men
Injecting drug users
Patients where HIV is a differential
What are some clinical indicator conditions for HIV testing?
Bacterial pneumonia TB Early onset dementia Peripheral pneumonia Severe psoriasis Severe seborrhoiec dermatitis Recurrent HSV Oral candidiasis Chronic diarrhoea of unknown cause Hep B/C Lung cancer Lymphoma High grade CIN Thrombocytopenia Neutropenia Lymphopenia Unexplained retinopathy Mononucleosis type syndrome
Do you need to consent for an HIV test?
Yes
Patients have the right to refuse
The reasons for testing should be explained, and written info on HIV should be provided
Verbal consent should be documented
How long does the HIV antibody take to develop?
4-8 weeks
How long after infection can the antigen be detected?
2-4 weeks
How long is the window period for HIV?
12 weeks
How long does it take to get a result from HIV testing!
48-72 hours
All positive tests must be confirmed by additional testing?
How long does the point of care testing for HIV take?
15-40 mins
What should be mentioned when counselling patients about HIV testing?
May be offered as screening - not necessarily expecting to find anything, and offered to everybody
Treatment is effective, normal life expectancy
Full medical confidentiality is assured
Think carefully before telling people about it
Negative tests do not affect insurance
Positive tests do, but only as much as other health problems eg. Back pain
How should transmission of HIV from mother to child be prevented?
If CD4 low - HAART
If CD4 high - HAART timing depends on maternal viral load
If VL undetectable at term, consider vaginal delivery
Neonatal PEP for 4 weeks
Avoid breastfeeding
Risk can be dropped from 45% to <1%
What is PEP?
Post Exposure Prophylaxis
What should be done to prevent HIV transmission due to occupational exposure to HIV?
Assess injury as to risk of transmission
HAART - 3 drugs for 28 days - aim for within one hour, definitely within 72 hours
Give antidiarrrhoeals and Antiemetics
Go to A+E or occupational health
