Johns- HIV Flashcards
What is the first step in viral replication and where is the is the of attachment?
HIV attaches to susceptible host cell Attaches to CD4 antigen found on: CD4 T cells macrophages moncytes B cells microglial brain cells intestinal cells
When is viral replication triggered? What may be destroyed in the process?
After period of latency, can last up to 10 years.
Replication occurs at a HIGH rate.
CD4 cells.
What causes symptoms of HIV to appear?
destruction of large number of CD4 cells
What are the methods of transmission of HIV?
sexual exposure to infected blood contaminated clotting factors sharing needles transplant mother to fetus
What is primary HIV syndrome?
MONO like, cold or flu-like sxs
can occur 6-12 wks after infection
lymphadenoapathy fever rash HA fatigue diarrhea sore throat neulogic
or no sxs present
When does the HIV Ab test become positive?
Usually 3-6 months after infection (seroconversion)
How do you diagnose primary HIV?
viral load titer assay or other test
What is the clinical latency period in HIV?
HIV continues to reproduce
CD4 gradually declines from its normal value of 500-1200
When is a pt w/ HIV at risk for opportunistic infections?
once cd4 count drops below 500
What diseases are predictive of progression to AIDS?
herpes zoster
oral candidiasis
oral hairy lekuoplakia
kaposi’s sarcoma
When does a pt have AIDs?
When CD4 ct drops below 200
What are AIDS pts at risk for if their blood count is below 200?
PCP (pneumocystis carinii pneumonia)
crptococcal meningitis
toxoplasmosis
What are AIDS pts at risk for if their CD4 count drops below 50?
myobacterium avium
CMV
lymphoma
dementia
When do most deaths occur?
CD4 counts below 50
What are the immunological manifestations of HIV?
Slight depression of CD4, few sxs
Ab detected by 6 months
P24 presents in first 6 weeks along with acute viremia and antigenemia
Abs produced to all major antigens
The first antibodies detected are produced against what proteins? Followed by?
gag proteins
p24
p55
Antibody to
p51
p120
gp41
What happens as the disease progresses
Ab levels decrease
What does ELISA testing do?
screen for HIV
What does a western blot do?
confirms HIV
What does the CDC require for a positive HIV test?
2 bands of the folllowing:
p24
gp41
gp 120/160
What are viral load tests used for?
tells you the quantity of HIV-RNA in the blood
Used to monitor treatment
What is the prognosis for HIV?
84% are alive in 10 yrs
what are the CDC’s HIV screening guidelines?
routine HIV testing to all persons 13-64 at least one regardless of risk w / repeat testing for person w/ risk factors
What is pneumocystis jiroveci?
The most common opportunitistic infection in HIV
yeast like fungus
usually found in healthy lungs but causes sxs in person w/ weak IS
