AIDS Flashcards
What type of virus is HIV
retrovirus
HIV Patho
There are two types HIV-1, HIV-2
HIV-2 is only seen in migrants from a certain part of Africa or in that specific location its self
Primarily infects CD4 tHelper cells by attaching to receptors on the CD4 membrane. The virus is released into cytoplasm of CD4. RNA>DNA>into nucleus>integrated into CD4 DNA>new viral RNA is created>viral proteins created>packaged together by protease>buds off of CD4 membrane to infect a new cell. Very rapid process.
CD4 count
measured in cells per mm
Normal: 800-1000/mm3
Symptoms begin when CD4 is around 500
<200 is dx of AIDS- you’ll see opportunistic infx
Viral load
measured in copies per mL
Goal is undetectable
<20 in the most sensitive tests
as the immune system fails, levels can reach up to 10to the 7th per mL
Timeline of untreated HIV
-First 6 weeks: viral load increases rapidly, CD4 count decreases rapidly. May have flu like symptoms
-6-12 weeks: CD4 some what normalizes, viral load decreases- detectible.
over the next 8-10 years: viral load is detectible, CD4 decreases, viral load increases. pt becomes severely immunocompromised
increased viral load is causative factor with reduced CD4 being the resulting factor
When to start HIV treatment
Immediately once the pt is diagnosed - stronger recommendation with the lower CD4 counts
Early treatment initiation:
pregnancy AIDS defining condition CD4 <200 Rapid decline of CD4 high viral load > 100000 copies HIVAN Hep B, Hep C, other coinfections Over age 50
ARV use pearls
mono therapy is harmful
HIV can mutate quickly, must sty on effective med as Rx
viral suppression requires a very high adherence of 95 percent or higher
high cost
Resistance testing
genotype: shows genetic sequencing- shows mutations to ARVs
Order at Dx, before ARV initiation, rebound of viral load
in all pregnant women before initiation
minimum viral load required for accurate testing is 500-1000 copies
5 classes of ARV are
fusion/entry inhibitors- prevents fusion to CD4 cell
nucleoside reverse transcriptase inhibitors NRTI and
nonnucleoside reverse transcriptase inhibitors NNRTI- both prevent transcription of RNA to DNA
integrase inhibitors II- prevent insertion
Protease inhibitors PI- inhibits the protease that packages the viral DNA/protein
Caveats to initial regimen
- ABC should not be used in pt who test + for HLA-B 5701
- TDF should be used with caution in renal insuffcency,-also known to decrease BMD
- DTG may cause higher risk of NTD when taken at time of conception
LABS
MET panel first 5-7 weeks
Renal Fx and urine q/6mo
Biktarvy
ARV 3-in-1 pill Bictegravir-TAF-emtricitabine preferred regimen: II and 2 NRTI same pregnancy concerns as DTG
Biktarvy
ARV 3-in-1 pill, once a day BIC-TAF-FTC preferred regimen: II and 2 NRTI same pregnancy concerns as DTG
Triumeq
ARV 3-in-1 pill, once a day DTG-ABC-3TC preferred regimen: II and 2 NRTI needs genetic testing
Ongoing monitoring of ARV treatment
viral load checked at 2-8wk after initial admin VL should be undetectable at 12-24wk CD4-VL every 3-6mos, PRN CMP, CBC, Fasting BG 3-6mo or PRN Kidney function for all pt on TDF
Opportunistic Infections
Community acquired Infx, HIV related Infx
all OI improve with reconstitution of immune system
PCP
candidiasis
KArposi Sarcoma
PCP- pneumocystis Jiroveci PNA
Aids defining OI CD4 <200 progressive, cough fever, chest pain some pt may have a clean CXR Rx- TMP/SMX 15-20/75-100mg/kg/d TID/QID for 14-21 days Taper steroids if hypoxic < 90
OI prophylaxis for PCP
CD4<200
TMP/SMX DS 1 daily
Dapsone 100mg daily
my dc when CD4 >200 x 3mos
candidiasis
Fluconazole 200mg PO daily x 14 days
OI prophylaxis for MAC
CD4<50
azithromycin 1200mg weekly, or 250mg daily
clarithromycin 500mg BID
Gold Standard for HIV testing
.
False positives can come from
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False negatives can come from
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Reverse transcriptase
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Which HIV med is not really excreted
.
4 initial regimens for HIV
BIC+TAF/FTC-
DTG+ABC/3TC-
DTG+TDF/FTC-
RAL+TDF/FTC-
TDF/FTC is what
Truvada
BIC+TAF/FTC- is what
.
DTG+TDF/FTC- is what
.
RAL+TDF/FTC- is what
.
DTG+ABC/3TC- is what
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