GUM Flashcards
What is HIV?
Human immunodeficiency virus
RNA retrovirus - HIV-1 most common
virus enters and destroys the CD4 T helper cells of the immune system
What is AIDS?
Acquired immunodeficiency syndrome which occurs as HIV infection progresses and the person becomes immunodeficient. leads to opportunistic infection
now mostly known as late-stage HIV
what is the progression of contracting HIV
initial flu-like illness occurs within few weeks of infection. infection is then asymptomatic until condition progresses to immunodeficiency
immunodeficient patients develop AIDS-defining illnesses and opportunistic infections - potentially years after initial infection
how is HIV transmitted?
- Unprotected anal, vaginal or oral sexual activity
- Mother to child at any stage of pregnancy, birth or breastfeeding - vertical transmission
- Mucous membrane, blood or open wound exposure to infected blood or bodily fluids, eg through sharing needles, needle-stick injuries or blood splashed in an eye
NOT KISSING
AIDS-defining illnesses associated with end-stage HIV infection occur where the CD4 count has dropped to a level that allows for unusual opportunistic infection and malignancies. what are some examples?
- Kaposi’s sarcoma
- Pneumocystis jirovecii pneumonia (PCP)
- Cytomegalovirus infection
- Candidiasis (oesophageal or bronchial)
- Lymphomas
- Tuberculosis
how should be screened for HIV?
almost everyone who is admitted to hospital with an infectious disease, regardless of risk factors
risk factors = test
how long can it take for a person to develop antibodies to HIV for and what implications does this have for testing?
up to 3 months
HIV antibody tests can be negative for 3 months following exposure so a repeat test is necessary if initial test is negative within 3 months of exposure
how long can it take for a person to develop antibodies to HIV for and what implications does this have for testing?
up to 3 months
HIV antibody tests can be negative for 3 months following exposure so a repeat test is necessary if initial test is negative within 3 months of exposure
do patients require formal counselling or education before an HIV test?
no
document verbal consent
what is the screening test for HIV?
antibody testing
blood test - can be self test sample which then gets posted to lab
testing for p24 antigen can give a positive result earlier in the infection
PCR testing for HIV RNA levels tests directly for number of viral copies in blood giving viral load
how is HIV monitored?
CD4 count
Viral Load (VL)
what us the CD4 count?
number of CD4 cells in the blood
these cells are destroyed by the virus so the lower the count, the higher the risk of opportunistic infection
what is the normal range for CD4 count and what is considered to be end-stage HIV (AIDS)
500-1200 cells/mm3 normal range
under 200 cells/mm3 is considered end stage
what is the viral load?
number of copies of HIV RNA per ml of blood
‘undetectable’ refers to viral load below the labs recordable range - usually 50-100 copies/ml
how is HIV treated?
combination of antiretroviral therapy (ART)
ART offered to everyone with a diagnosis of HIV irrespective of viral load or CD4 count
BHIVA guidelines recommend starting regime of 2 NRTIs plus a third agent
what is the aim of HIV treatment?
achieve a normal CD4 count and undetectable viral load
when a patient has a normal CD4 and an undetectable viral load on ART, treat their physical health problems as you would an HIV negative patient
HAART stands for highly active anti-retrovirus therapy. what are some examples?
- Protease inhibitors (PIs)
- Integrase inhibitors (IIs)
- Nucleoside reverse transcriptase inhibitors (NRTIs)
- Non-nucleoside reverse transcriptase inhibitors (NNRTIs)
- Entry inhibitors (EIs)
what are some additional managements for patients with HIV?
prophylactic co-trimoxazole given to pt with CD4 under 200/mm3 to protect against pneumocystis jirovecii pneumonia (PCP)
close monitoring of cardiovascular risk factors and blood lipids as increased risk of cardiovascular disease
yearly cervical smears for women as predisposes to HPV infection
vaccination up to date - influenza, pneumococcal, hepatitis A&B, tetanus, diptheria, poilio BUT AVOID live vaccines
what sexual health advice can you give to couples regarding HIV?
advise condoms and dams for oral sex even if both positive
if VL is undetectable, transmission through unprotected sex is unheard of but not impossible
partners should have regular HIV tests
what advice can you give couples trying to conceive?
where undetectable viral load, unprotected sex and pregnancy may be considered
also possible to conceive safely through techniques like sperm washing and IVF
when can a woman with HIV have a normal vaginal delivery?
viral load < 50 copies/ml
what is cs needed in women with HIV?
Considered in patients with >50 copies
All women with >400 copies/ml
what should be given during the CS if viral load is unknown or there are >10000 copies/ml?
IV zidovudine
an antiviral medication
what prophylaxis treatment is given to the baby and what is given at what viral loads?
- Low-risk babies (viral load is < 50 copies per ml) = zidovudine for 4 weeks
- High-risk babies (viral load is > 50 copies / ml) = zidovudine, lamivudine and nevirapine for 4 weeks