HIV + labs/dx tests Flashcards
HIV/AIDs
human immunodeficiency virus
acquired immunodeficiency syndrome
same disease/virus
when are you considered to have AIDs?
final stage of viral infection (before death)
CD4: <200
OR specific opportunistic infection occurs –>
-Burkitt’s lymphoma
-pneumocystis jirovecii
-HIV-related encephalopathy
-kaposi’s sarcoma
-disseminated histoplasmosis
-candidiasis of esophagus/bronchi
collaborative management of HIV patient?
-manage symptoms
-monitor progression and immune fxn
-initiate/monitor anti-retroviral therapy (ART)
-prevent opportunistic infections
-prevent complications
-prevent spreading disease
preventative measures for a person with HIV
-avoid/modify risk factors
-safer sex (handouts - male & female condoms)
-decrease risk r/t drug use (stop or needle exchange programs)
-decrease risk of perinatal transmission
-encourage routine HIV testing
-decrease risk at work
potentially infectious substances from HIV patient
blood
cerebral spinal fluid (CSF)
synovial fluid
pleural fluid
amniotic fluid
what is considered exposure?
needle stick or cut with sharp object
mucous membrane contact
non-intact skin contact
post-exposure prophylaxis
initiate drug therapy ASAP –> within 1-2 hours, especially within 72 hours
undergo HIV testing
patient education on ART
advantages and disadvantages
dangers of non-adherence
how and when to take drugs
drug interactions to avoid
side effects to report to HCP
strategies to promote adherence and improve outcomes
-ensure motivation before 1st prescription
-social support
-negotiate a treatment plan
-devise a simpler regimen
-anticipate side effects
-establish trust
candidates for Pre-Exposure Prophylaxis (PrEP)
-anal or vaginal sex in last 6 months
-sexual partner with HIV
-not consistently using condoms
-been diagnosed with an STD in past 6 months
-inject drugs
-injection partner with HIV
-share needles, syringes, etc.
PrEP
daily meds to lower chance of getting HIV (Truvada and Descovy) –> highly effective if used as prescribed
reduces risk of getting HIV through sexual contact by 99% when taken consistently –> 74% if using IV drugs
what should you teach PrEP candidates?
continue to use condoms
often covered by insurance and medicaid, free medication programs available and co-pay assistance
does NOT protect against other STIs
education for patient with AIDS
-avoid crowded areas or traveling to countries with poor sanitation
-avoid raw foods (uncooked fruits and vegetables) and undercooked foods
-avoid cleaning pet litter boxes
-keep home environment clean, don’t allow sick friends or family to visit
-continue ART
-frequent monitoring of CD4 and viral load labs
HIV screening is recommended for
13-75 years old
pregnant
if at risk, all ages
routine screening
one time
yearly screening for high risk patients includes
-men who have sex with men
-injection drug users
-people who exchange sex for drugs/money
-sex partners of people who are HIV infected, bisexual,, or injection drug users
-person who has sex w partner who HIV status is unknown
Implications of HIV screening
-consent: voluntary, ensure they understand, offer to opt out –> document if they opt out
-confidentiality: scrupulous attention to this
-counseling: available to educate reducing likelihood of exposure
-referral to care: have the option of where to go if positive
CDC estimates
85% aware of HIV status
62% linked to HIV care
41% stay in HIV care
36% get ART
28% are able to adhere to their treatment and sustain undetectable viral loads
types of HIV testing
*HIV antibody only
*combination - HIV antibody AND HIV antigen (4th gen)
*HIV RNA
HIV antibody only test
ELISAs: enzyme-linked immunosorbent assays
HIV-1/HIV-2 differentiation assays
*western blot: confirmatory follow up testing
older
combination test
antibody AND antigen
almost 100% specificity and sensitivity
able to identify early/acute infections in up to 80% of pt.
2 available combo rapid tests
HIV RNA test
actual viral load level
*qualitative: used as a screener to identify HIV-infected individuals (ex: blood donors)
*quantitative: used to manage/monitor those who are infected; can also be used to diagnose
if the initial test is positive, what are the next steps?
all initial positive tests are confirmed with another test
the newer generation of tests –> the earlier the possibility of detection
positive result
positive ELISA or combination assay followed by a positive confirmatory test
negative result
negative screening ELISA or combination assay
indeterminate result
when ELISA or combination assay is positive but confirmatory test is indeterminate or negative
window period
time between potential exposure to HIV infection and the point when the test will give an accurate result
during window period–> VERY infectious but tests are negative
time it takes to develop antibodies
95% by wk 4
>99.9% by wk 12
2-3 weeks most infectious
what do you want the CD4 count and viral load to be?
CD4: HIGHER (>500)
viral load: LOWER (<50)
CD4 count indicates
how healthy the immune system is
CD4 count monitors
progression of AIDS
risk for opportunistic infections –> helps determine when it’s time for prophylactic treatment
*check every 3-4 months – with stable untreated patients and patients on ART therapy
CD4 count normal range
800-1200 cells
reported in actual numbers or “copies”
CD4 count < 200
infected person becomes vulnerable to any of ~26 opportunistic infections and rare cancers
viral load testing indicates
how active HIV is in the body
viral load and HIV infection
untreated –> replication usually produces billions of new viral copies daily
plasma HIV RNA (viral load) quantifies viral burden in plasma
helps monitor response to ART (along with CD4 ct)
check q 3-4 months
**lowest level of detection differs with each test
what does an “undetectable viral load” mean?
GOAL –> unable to detect HIV in plasma
does NOT indicate absence of clearance of virus from body
recommendation: check twice at baseline before starting ART - when stable, q 3-4 months
labs worth monitoring with HIV
WBC
platelets
H&H
LFTs (liver function tests) - early detection of co-infection with HBV or HCV impt
can also test for resistance to ART drugs
