HIV Flashcards
How does HIV attach to and enter human cells?
Uses glycoprotein 120 and glycoprotein 41 to attach to CD4 molecules and coreceptor CCR5 or CXCR4
How was a patient with HIV cured?
Received a bone marrow transplant for leukaemia from a donor who was homozygous for a CCR5 mutation
What causes the seroconversion illness in HIV?
Killing of infected CD4 lymphocytes by CD8 lymphocytes at around 3-4 weeks after infection
Why are there different clones of virus in HIV patients?
Because the virus replicates via a reverse transcriptase that is error prone which means that there can be clones that are poorly recognised by the cytotoxic lymphocytes
Why do people with HLA-B*57.01 have more effective cytotoxic responses against HIV?
Because this HLA type binds a peptide from the HIV core protein that is essential for replication therefore won’t be mutated
What is the mechanism of action of tenofovir?
Nucleoside reverse transcriptase inhibitor
What are the common mechanisms for HIV medications?
Reverse transcriptase inhibitors
Integrase inhibitors
Protease inhibitors
What is the mechanism of action of zidovudine?
Nucleoside reverse transcriptase inhibitor
What are the side effects of zidovudine?
Lipodystrophy, metabolic effects, GI side effects
What is the mechanism of action of lamivudine?
Nucleoside reverse transcriptase inhibitor
What is the mechanism of action of emtricitabine?
Nucleoside reverse transcriptase inhibitor
What is the mechanism of action of abacavir?
Nucleoside reverse transcriptase inhibitor
Which patients will have hypersensitivity to abacavir?
HLA-B57*01
What is the side effect of tenofovir disoproxil fumarate?
Nephrotoxicity, reduced bone mineral density
What monitoring needs to be done for tenofovir disoproxil fumarate?
6 monthly creatinine, phosphate, urine protein
What is the difference between tenofovir alafenamide and tenofovir disoproxil fumarate?
Tenofovir alafenamide has a longer plasma half life so less renal exposure so reduces nephrotoxicity
What is the mechanism of action of nevirapine?
Non nucleoside reverse transcriptase inhibitor
What is the mechanism of action of efavirenz?
Non nucleoside reverse transcriptase inhibitor
What is the mechanism of action of rilpiverine?
Non nucleoside reverse transcriptase inhibitor
What is the mechanism of action of delaverdine?
Non nucleoside reverse transcriptase inhibitor
What is the mechanism of action of etravirine?
Non nucleoside reverse transcriptase inhibitor
What is the mechanism of action of doravirine?
Non nucleoside reverse transcriptase inhibitor
What are the side effects of nevirapine?
Hypersensitivity reactions including hepatitis (stop if rash)
What are the side effects of efavirenz?
Sedation/insomnia, vivid dreams, neuropsych symptoms, deranged LFTs, rash
What are the side effects of rilpiverine?
Prolonged QTc
What are the side effects of delaverdine?
Rash, headache
What are the side effects of etravirine?
Rash, GI side effects
Why is ritonavir used in HIV?
It inhibits CYP3A4 so will increase the effect of other protease inhibitors
What is the mechanism of action of lopinavir?
Protease inhibitor
What is the mechanism of action of atazanavir?
Protease inhibitor
What is the mechanism of action of darunavir?
Protease inhibitor
What are the side effects of atazanavir?
Elevated bilirubin, renal stones
What are the side effects of darunavir?
Rash
What is the mechanism of action of raltegravir?
Integrase inhibitor
What is the mechanism of action of elvitegravir?
Integrase inhibitor
What is the mechanism of action of dolutegravir?
Integrase inhibitor
What is the mechanism of action of bictegravir?
Integrase inhibitor
What are the side effects of raltegravir?
Elevated CK/rhabdo
What are the side effects of dolutegravir?
Headache, depression/anxiety, neural tube defects
What are the side effects of bictegravir?
Headache, GI side effects
What PEP should be offered to someone who has sexual exposure to a known HIV positive case when the viral load of the source is unknown?
3 drug PEP
What PEP should be offered to someone who has sexual exposure to a known HIV positive case when the viral load of the source is undetectable?
None
What PEP should be offered to someone who has occupational exposure to a known HIV positive case and the source has unknown viral load?
3 drug PEP
What PEP should be offered to someone who has occupational exposure to a known HIV positive case and the source has a known undetectable viral load?
Consider 2 drug PEP
What PEP should be offered to someone who has sexual exposure to a source with unknown HIV status?
2 drug PEP if source MSM or from high prevalence country (risk <1/1000 and >1/10000)
What drugs are used for PrEP?
Tenofovir and emtricitabine
When does PEP need to be started?
Within 72 hours
How long is the course of PEP?
28 days
What drugs are used for 2 drug PEP?
Tenofovir AND emtricitabine OR lamivudine
What drugs are used for 3 drug PEP?
Tenofovir AND emtricitabine OR lamivudine AND EITHER dolutegavir OR raltegavir OR rilpivirine
Who should get PrEP?
All people with behaviour that poses high risk of HIV acquisition
What is the efficacy of PrEP?
90-99%
What is the usual clinical presentation for PJP?
Progressive exertional dyspnoea, fever, non productive cough, desaturating on mobilising
What is the treatment for PJP?
Cotrimoxazole
Who should get primary prophylaxis for PJP?
Patients with newly diagnosed HIV or CD4 count < 200
What is the usual clinical presentation for Cryptococcus meningitis?
Sub acute headache and fever, may have behavioural changes or confusion, meningeal features are late
What is seen on LP for cryptococcal meningitis?
Raised opening pressure, slightly raised WCC and protein, low glucose, india ink and CRAG positive
What is the treatment for cryptococcal meningitis?
Therapeutic LP
Amphotericin plus fluctyosine for 2 weeks followed by 8 weeks of fluconazole
