HIV/AIDs Management Flashcards
HIV patho
retrovirus attacks immune system; targets T cells w/ CD4 receptors
CD4 T cells - WBC that fight infection; T cell count lowers overtime
virus enters cell + replicates = CD4 cells die
if untreated –> AIDS
HIV transmission
body fluids - blood, semen, rectal fluids, vaginal fluids, amniotic fluids + breast milk
infected fluid MUST come in contact w/ open mucous membrane (damaged tissue or direct injection to bloodstream)
high risk: anal/vaginal sex (no condom), sharing needles or syringes (can live up to 42 days)
perinatal - preg women test; if given tx 4 - 6 wks –> risk of transmission less than 1%
rare HIV transmission
oral, unless blood, sores, or other STIs are present w/ person with HIV, deep open-mouth kissing
(NOT transmitted by saliva, tears or sweat, hugging, shaking hands, sharing toilets, sharing dishes, or closed-mouth kissing, mosquitoes, ticks or other blood sucking insects)
HIV testing recs
CDC recs ages 13 - 64 get tested for HIV
high risk ppl @ least once a year or more
preg women
early detection is key! (high risk of transmission)
HIV diagnostic tests
standard tests - blood, done in lab
rapid antibody screening tests - blood from finger prick or oral fluids
initial positive rapid antibody test must be followed by a confirmatory lab based combo antigen-antibody assay
**neg test does not have to be confirmed
antibody only tests - pos test requires confirmatory test
combo antigen/antibody tests
HIV-1/HIV-2 immunoassay
HIV-1/HIV-2 differentiation assays
viral detection - HIV P24 antigen test, NAT, HIV RNA
antibody only tests
initial ELISA (positive) –> western blot
- can fail to diagnose individuals who are early in the course of their infection when antibody has not fully developed
- accuracy of this test for pt w/ chronic infection is extremely high (>99% sensitivity + specificity)
rapid antibody screening tests
- pros: convenient + cheap
- 5 to 40 mins
- mail order or send in
- buy online or at pharmacy for rapid test
combo antigen/antibody test
acute/early infection identifiable
pos test is followed by second test to confirm results
combo ag/ab test can detect HIV p24 antigen when antibody may not be present
HIV-1/HIV-2 immunoassay
detects HIV antibodies and P24 antigen
follow up with confirmatory tests
HIV-1/HIV-2 differentiation assays
differentiates b/t HIV-1 or HIV-2 (or both)
*HIV-2 less common than HIV-1 in US; need to know for tx decision making
viral detection
establishes HIV diagnosis since virus is present in blood before HIV antibodies can be detected
most common tests are to detect HIV RNA (viral load) or HIV P24 antigen (foreign antigen)
HIV P24 antigen test - detectable ~1-2 wks after viral transmission (cheaper than NAT + identifies approx 80-90% during acute infection
nucleic acid amplification testing (NAAT) - multiple different lab tests; used to detect genetic material of HIV in blood
HIV RNA - type of NAT; detects amount of HIV virus in body or “viral load”; should be performed if concern for ACUTE HIV infection
HIV monitoring and assessments
HIV RNA (viral load)
CD4+ T lymphocyte cell count (or CD4 count) - level of immune function
HIV RNA
viral load - amount of virus in blood
undetectable or low - 20-50 copies/ml
acute phase - very high plasma HIV RNA levels > 100k copies/mL
goal = to reduce HIV viral load to an “undetectable” level
CD4+ T lymphocyte cell count
level of immune function; used to stage disease
norm 500 - 1500
<200 - indicator of AIDS
monitors CD4 cell destruction
effectiveness of antiretroviral tx (ART)
best indicator of dx progression
decline of CD4 cells lead to opportunistic infections + inc mortality
initial transmission
(stage 0-1)
large amounts of virus in the blood, extremely contagious
within 2 to 4 weeks after infected w/ HIV, may have a flu-like symptoms or no symptoms
may not know have HIV since symptoms mimic other illnesses
**to test for acute infection - antigen/antibody or NAT is necessary
