HIV Flashcards
Hiv transmission in neonates
Mode
Risk at delivery vs antenatal
Risk with intervention
Vertical in 95%
70% at delivery
30% antenatal
BF 5-20% post partum
3 ARVs, no BF 1%
HIV presentation
Major
Minor
Major
Wt loss (10% of body wt)
Chronic diarrhoea
Prolonged fever
Intermittent fever for >4w
Minor
Persistent cough >4w Generalised dermatitis Recurrent herpes zoster Oropharyngeal candidiasis Generalised lymphadenopathy
CD4 count where different diseases occur
400
200
100
20
400- TB, herpes zoster, thrush, HSV
200- pneumocystosis
100- toxoplasmosis, atypical mycobacteriosis, CMV,
20- PML
HIV antigen occurs how long after infection
EIA detects
NAAT testing detects
1-2 weeks
EIAs detects antibody and antigen
NAAT detects DNA and RNA
Adverse effects of ART
AZT
Nausea and vomiting Hepatitis, liver dysfunction Myopathy Osteoporosis SJS/TEN Granulocytopenia
What vaccine contraindicated in HIV
Which should not be given if immunosupressed
BCG and LIVE influenza
MMR
Varicella
BCG vaccine type
Live attenuated
When can ELISA and western blot HIV tests start to be relied upon?
What can be used in the interim?
After 18months
NAAT
Detects RNA and DNA
1,2,4 months
Match- ARTs and action
Competitively inhibit HIV reverse transcriptase, requires intracellular phosphorylation for activation
Inhibits HIV reverse transcriptase, binds active site directly
Inhibit HIV protease
NRTIs, eg. Zidovudine, Lamivudine
NtRTI same mechanism of action
Eg. Tenofovir
NNRTIs, eg. Nevirapine
PIs
Lipodystrophy
S/E of which class of ART?
Protease inhibitors
HIV neurological disease
Masses (3)
Meningitis (3)
Diffuse brain disease (2)
Toxoplasmosis
Tuberculoma
Lymphoma
Cryptococcus
Bacterial: salmonella nontyphi, pneumococcus
HIV encephalopathy
HSV/VZV
Western blot detects….
Brief summary of process
Protein
Proteins denatured
Gel electrophoresis
Wash in primary antibody: binds target protein
Wash off excess
Apply secondary antibody
Image under immunofluorescence or staining
HIV
Low risk MTCT
Treatment
High risk MTCT
Treatment
Undetectable viral load
No BF
Zidovudine for 4 weeks (test at 6, 8 weeks)
Detectable viral load
Late presentation
Dx after delivery
AZT, 3TC, Nevirapine - until negative confirmed by Ab testing at 18 months
Antigens which EIA detects antibody to in HIV
Gp120, gp160, gp41
Antigen on HIV envelope
Takes 1-2 weeks to appear in serum
HIV viral resistance
Inevitable if…
Associated mutations in …
Outcome of viral resistance
Inadequate adherence
RT or protease genes
More likely for treatment to fail
