Testing, testing
What are the three different types of HIV testing?
Antibody
Antigen/antibody
Nucleic acid (amplification) Test
What cell does HIV lead to a decline in?
CD4+ cells (T helper cells)
Antiretrovirals
How long after infection can each test detect HIV?
Antibody: 3-12 weeks
Antigen/antibody: 2-4 weeks
Nucleic acid Test: As soon as 10 days after exposure
What is the role of CD4+ cells?
Coordinate the immune system by releasing cytokines:
- Activating B cells to produce antibodies specific to that antigen
- Stimulate cytotoxic T cells to kill infected or abnormal cells
- Mediate the response from other immune cells
Give a reason why confidentiality may need to be broken
Duty to Warn - If the patient knowingly exposes others to HIV without disclosing their status, you have an obligation to inform those at risk.
What is the limitation of Nucleic Acid Testing?
Extra: What is it’s use case?
High Cost: Not practical for routine screening.
Specific Use Cases: Primarily used to monitor treatment effectiveness (e.g., ART) or confirm recent exposure when other tests are inconclusive.
What is the CD4 threshold under which someone is diagnosed with AIDS?
200 cells per cubic millimetre
What are the key elements of informed consent when discussing tests for devastating conditions?
Voluntary decision
Sufficient information
Patient's capacity to understand and make the decision
Why is early detection of HIV important for patient outcomes?
Early detection allows for timely intervention, which can:
- reduce the risk of transmission
- improve the effectiveness of ART
- decrease the long-term health consequences of HIV.
What is the adjective given to describe infections that happen in people with AIDS + the name of one of these infections?
Opportunistic
What steps should be taken if a patient consents to testing but later decides they do not want to know the results?
Respect their choice, provide counselling, and document their decision in case they wish to revisit it later.
What is the protein tested for in antigen HIV testing?
p24 antigen
Via what protein does HIV bind to the CD4 receptor
Gp120
Why is confidentiality particularly important when testing for a devastating condition?
To protect the patient’s privacy and prevent potential discrimination or stigma associated with the condition.
What is the recommended course of action after possible HIV exposure, to prevent infection?
+ time within it should be started
Post-Exposure Prophylaxis (PEP), to be started within 72 hours of exposure.