Exam 2 Flashcards
What are the ways HIV can be transmitted?
What are the risks (%) of transmission through a transfusion?
- Blood
- Semen
- Vaginal secretions
- Breast milk: also through pregnancy and delivery
Only 1% risk of infection through a blood transfusion.
How long is the window between exposure and when antibodies show up?
What is the percentage of risk for healthcare workers after a needle stick?
What % of babies are born from untreated infected mothers who get HIV?
A few weeks.
0.3 - 0.4%
25% : Risk decreases to only 2% in those receive ART.
The biggest risk is delivery.
How long can infants test positive for HIV antibodies after delivery?
Up to 18 months.
What does PEP mean?
What do we test for when we are at risk for transmission?
What does PPE mean?
Post-Exposure Prophylaxis.
This should be started within hours of possible transmission.
We are tested for HIV, HBV (hep B), and HCV (hep C)
PPE: Personal Protective Equipment
Duration/frequency of contact Volume of fluid Virulence of organism Host immune status and Viral load of fluid are all factors that affect what?
Transmission depends on these factors.
What kind of receptors are needed in order for the HIV to infect cells?
How many CD4-T cells are killed each day?
What parts of the body initially replace these with?
CD4 receptors.
About a billion CD4-T cells are killed/day.
The thymus and bone marrow initially replace.
Thymus = produce and mature T cells
Bone marrow = stem cells -> T cells -> thymus for maturity.
What is the normal range for CD4 cells?
500 - 1500 cells/mm3
What are the stages of HIV infection?
- Acute - primary (or initial) HIV infection (about 2-4 weeks): begin to develop “off” feelings, similar to flu/mono/palsy/meningitis. Also seroconversion occurs.
- Chronic - 6 months or longer: low viral load. With ART, this stage can last up to 40 years.
- Late stage or AIDS - CD4 count 200 or below. Opportunistic infections.
During this stage, there is an undetectable viral load and many may think they are “cured.”
Where are the latent reservoirs located?
Chronic stage.
There are latent reservoirs where the virus “hang out” undetected. Means that ART is working.
Reservoirs: Blood Brain Lymph GI
If the patient does not manage their HIV infections strictly, what may happen?
S/S of dz progression?
- Resistance
- Dz progression
S/S
- Increased viral load
- CD4 drops below 500 (200-499)
- Symptomatic progression
- Opportunistic infections and CA’s
Oral hairy leukoplakia, Shingles, Candida, Herpes outbreaks (oral/genital), Bacterial infections, and Kaposi sarcoma are all examples of what?
Opportunistic infections.
FYI: Oral hairy leukoplakia (luke-oh-play-key-uh) is from the Epstein-Barr virus (same as mono).
May also see some cervical dysplasia… abnormal cells that progress into CA.
What is the difference between antiviral drugs and antiretroviral drugs?
AntiVIRAL:
Target diverse group of viruses such as herpes, hepatitis, and influenza viruses.
AntiRETROviral:
Used to fight retrovirus infections which mainly include HIV. Different classes of antiretroviral drugs act on different stages of the HIV life cycle.
What level of CD4 indicates AIDS?
What happens to the viral load at this time?
Under 200.
Viral load is pretty high.
What are some common complications involved with AIDS?
- Dementia
- Wasting Syndrome
- Opportunistic infections: Candidiasis in bronchi and below Cytomegalovirus (CMV) Toxoplasmosis Tuberculosis Invasive cervical CA Kaposi's sarcoma (KS) Cryptococcal meningitis Mycobacterium avium complex (GI s/s) Non-Hodgkins Lymphoma Pneumocystis carinii pneumonia (PCP)
Which opportunistic infection is big with AIDS and has a high mortality?
s/s?
Tx?
Pneumocystis carinii pneumonia (PCP)
1 in 10 hospitalized HIV pts have PCP
s/s
- Nonproductive cough, wheezing
- SOB (esp with exertion)
- low grade fever
- fatigue
- chest pain when breathing
Tx: Pentamidine, an antifungal and antiprotozoal agent
What is Pentamidine used for?
What are it’s side affects?
How is it administered?
Pentamidine is used to treat Pneumocystis carinii pneumonia (PCP).
It is an antifungal and antiprotozoal agent.
It’s side affects include:
- Severe hypotension (significant enough that this drug is given while the patient is lying down)
- Arrhythmias (on cardiac monitor)
- Nephrotoxic
- Extravasation and tissue damage
Administered by IV
What virus is responsible for Kaposi’s sarcoma?
Related to human herpes virus 8 (HHV-8)
Develops when infected cells that line lymph or blood vessels begin to divide without stopping and spread into surrounding tissues. Whereas most cancers begin in one part of the body and may later spread to other areas, KS can start in several parts of the body at the same time.
What do we call weakness and wasting of the body due to severe chronic illness?
Cachexia.
What are the following symptoms signs of?
Chronic diarrhea for more than 30 days. Greater than 10% weight loss Chronic weakness/fever Cachexia and malnutrition GI malnutrition
Wasting Syndrome
Not helped by increased protein or calories.
May be due to mycobacterium avium500
What are some other signs that the body is shutting down?
- Neutropenia (under 500)
- Anemia
- Thrombocytopenia
- Altered liver functions (AST/ALT enzymes)
- Hep B or C
How do we diagnose HIV?
- Test for HIV antibodies (HIV antibody assay; Not detectable for about 2 months)
- Rapid testing can be done in 20 minutes
- HIV antibodies can be found in the blood, urine, and saliva (the virus is NOT in the saliva, just antibodies)
- All infants born to HIV+ moms will be antibody positive for up to 18 months.
Where can HIV antibodies be found?
Blood, urine, and saliva.
How many positive tests are needed for dx?
If you have a + rapid test, which test is next?
If you have a + EIA and a negative Western blot, then what do you need to test for?
Need 2-3 positive tests.
If you have a positive rapid then it is followed with a Western blot test.
If you have a positive Enzyme Immunoassay (EIA) and a negative Western blot, then you need to test for HIV RNA
How are we to interpret the positive HIV test?
- HIV antibodies are present in the blood
- HIV is active in the body, is transmittable
- Does not necessarily have AIDS
- Not immune to AIDS - still may/will develop if non-compliant.
Goals of HIV treatment include:
Lowering the viral load to < 50 copies, maintain CD4T cells at >350, delay development of symptoms… and what else?
- Prevent development of viral resistance to the therapy drugs (strict compliance is needed)
- Maintain quality of life
- Protect others
- Support person in coping with disease and dying
What does ART mean?
What is HAART?
What is the difference?
ART = Antiretroviral Drug Therapy
HAART = Highly Active ART
HAART is newer and doesn’t require the same level of strict-regimen.
These drugs delay the dz progression, reducing the viral load thereby reducing transmission risks.
Drug therapy is a combination of drugs that attack the virus in different ways and at different times in the replication cycle = lowers risk of resistance.
Very expensive = $1300/month w/out insurance
Usu. many pills to take at specific times of the day
Can reduce viral load by 90-99%
What are some typical ART drugs?
Saquinavir
Abacvir
Dolutegravir
What are some common antiviral drugs?
Acyclovir (herpes)
Oseltamivir (influenza)
Why is strict compliance so imperative with ART?
If the adherence to the schedule is not upheld, resistance can happen rapidly. (use alarms, pill minders, etc)
Some ART users will not respond to tx, these individuals will progress through the dz to AIDS.
Some may not be able to use: $, side effects, inability to adhere to schedule (we shouldn’t make decision), many ART drugs interact with OTC and other Rx drugs (making it more complicated)
When should ART be started?
When in pregnancy?
- Start when CD4 is down to 350 and keep it above 350.
- ART will decrease transmission to uninfected partners by 96%
- The newest therapy (2012) you start ASAP, preferably at the time of dx, regardless of the CD4 levels.
- Pregnancy: ART should be started in the 1st trimester.
PEP versus PrEP
PEP is Post-Exposure Prophylaxis
PrEP is Pre-Exposure Prophylaxis
