HIV and AIDs Flashcards
What does HIV stand for?
1 - Human immunodeficiency virus
2 - Human inpatient virus
3 - Hepatic Immunodeficiency Virus
4 - Hypersensitivity Immunological Virulence
1 - Human Immunodeficiency Virus
- leads to a gradual loss of immune function
What does AIDs stand for?
1 - allport infrection disease
2 - acquired immunodeficiency syndrome
3 - acquired immunodeficiency syndrome
4 - acquired infection system
2 - acquired immunodeficiency syndrome
- following HIV the reduced immune system leads to systemic immunodeficiency
- increases the risk of infections and tumours, which would not generally infect
In early acute phase of the HIV infection the viral load will increase as the virus infects the patient. This can typically present with flu like symptoms as the immune system mounts an immune response. In 40-90% of patients, how long is it before symptoms present?
1 - <48h
2 - >1 week
3 - <7-10 days
4 - <3 weeks
3 - <7-10 days
- can be longer, but this is the most common
In the acute phase of HIV which cell type is targeted and gradually declines?
1 - dendritic cells
2 - macrophages
3 - CD4 T helper cells
4 - CD8 T cytotoxic cells
3 - CD4 T cells
- normal levels are between 500-1500
What determines when a patient moves from HIV to AIDs?
1 - age of patient
2 - strain of HIV
3 - immunocomprimised co-morbidities
4 - T cell number
4 - T cell number
- <200 = AIDs
What is often the first presenting symptoms of AIDs?
1 - hair loss
2 - anaemia
3 - infection
4 - cardiac problems
3 - infection
- opportunistic infections which the immune system would normally resist
Which receptor on T helper cells does the HIV bind with?
1 - Toll Like Receptors
2 - CD4
3 - IL-6 receptors
4 - CD8
2 - CD4
CD4 on T helper cells is what HIV will bind with to infect cells. However, it also requires a 2nd co-stimulation. What is this receptor on the HIV called?
1 - CD40
2 - P2Y12
3 - B7
4 - Gp120
4 - Gp120
- refers to enveloped glycoprotein
CD4 on T helper cells is what HIV will bind with to infect cells, with co-stimulation from Gp120 receptor on the HIV cell. However, it also requires a further co-stimulation from a receptor that is present on T cells, macrophages, monocytes and dendritic cells. What is this co-stimulatory receptor called?
1 - CXCR4 and CCR5
2 - CD4XR and CCR5
3 - CTXR8 and CCR5
4 - CXC and CCR5
CXC = chemokine
R = receptor
1 - CXCR4 and CCR5
- doesn’t need to bind both, one or the other
- CCR5 is MOST COMMON IN EARLY INFECTION
- CXCR4 IS MORE COMMON IN LATE INFECTIONS
Once the HIV has bound to a CD4 cell, it is able to release its contents into the cell. HIV contains single stranded (ss) RNA ( retrovirus. What does the virus require in order for its viral DNA to be incorporated into the CD4 DNA within the nucleus?
1 - to be copied by the ribosome
2 - to bind with receptors on nucleus
3 - to bind with reverse transcriptase
4 - to destroy lysosomes within the cell
3 - to bind with reverse transcriptase
- this is where the retro part of the virus comes from
- this allows the ssRNA to be copied and integrated into the host DNA
Once HIV has been incorporated its DNA into the CD4 T helper cell. When does the T cell then copy its DNA and in doing so replicate the HIV code instead, resulting in the production of HIV proteins?
1 - only when the T cell has been activated
2 - only when the T cell has been activated and clonally expands
3 - as soon as it is incorporated into the T cells DNA
4 - whenever HIV instructs it to do so
2 - only when the T cell has been activated and clonally expands
- occurs once the patient is infected with HIV
To gain entry into a host cell, HIV will need to bind with CD4 through its Gp120 receptors, followed by co-stimulation with CXCR4 or CCR5. The function of CXCR4 or CCR5 is chemotaxis and HIV suppression. So when a cell becomes infected with HIV the CD4 T helper cell up-regulates CXCR4 or CCR5 receptors to signal an immune response and fight the HIV. Why is this bad though?
1 - initiates an immune response
2 - attracts immune cells including dendritic, CD4 T cells and monocytes
3 - increased CXCR4 and CCR5 co-receptors on host immune cells available for HIV to bind with
4 - leads to increased number of immune cells that HIV can infect
5 - all of the above
5 - all of the above
What is thought to be the main sites for HIV infection to occur?
1 - genitourinary, gut and oral mucosa
2 - vagina, oral mucosa and bronchi
3 - penis, oral and gut
4 - intravenous, gut and oral
1 - genitourinary, gut and oral mucosa
- high number of CD4 cells with CCR5 receptors are present, so lots of chance to infect
The GIT is thought to be the main site for HIV infection to occur due to the high number of CD4 cells with CCR5 receptors present, so lots of chance to infect. In early infection the mucosa is able to shed and the HIV virus with CD4 are removed from the GIT as faeces. However, as a large number of CD4 cells have been removed alongside the HIV, what infection does this increase the risk of?
1 - inflammatory bowel disease
2 - cytomegalovirus causing colitis
3 - coeliac disease
4 - salmonella
2 - cytomegalovirus causing colitis
The R5 strain of the HIV is following infection in the GIT, where the virus then travels to lymph nodes where it is able to infect other immune cells. Where does the name R5 come from?
1 - name given when it was discovered
2 - name given by person who discovered it
3 - R5 HIV strain binds to CCR5 co-receptor
4 - R5 HIV strain binds to CXCR5 co-receptor
3 - R5 HIV strain binds to CCR5 co-receptor
The X4 strain of the HIV generally comes on in chronic late infections with HIV. Where does the name X4 strain come from?
1 - name given when it was discovered
2 - name given by person who discovered it
3 - X4 HIV strain binds to CCR5 co-receptor
4 - X4 HIV strain binds to CXCR4 co-receptor
4 - X4 HIV strain binds to CXCR4 co-receptor
In the acute infection phase of HIV, why is it crucial that infected patients do not have sex?
1 - can make themselves sicker
2 - may acquire HIV again and increase viral load
3 - viral load is at its peak so increased risk of spreading
4 - all of the above
3 - viral load is at its peak so increased risk of spreading
In a patient infected with HIV, due to the reduction in CD4 T helper cells there is a loss of control of commensal bacteria, resulting in an increase in what?
1 - gram negative peptides
2 - gram positive peptides
3 - gram negative lipopolysaccharide
4 - gram positive lipopolysaccharide
3 - gram negative lipopolysaccharide
- leads to inflammation NF-Kb and TNF-a activation
In a patient infected with HIV, due to the reduction in CD4 T helper cells there is a loss of control of commensal bacteria, resulting in an increase in gram negative lipopolysaccharides that can then lead to inflammation NF-Kb and TNF-a activation. Why is this a bad thing?
1 - initiates an immune response and upregulation of CCR5
2 - downregulates immune response and increases risk of infection
3 - induces bacteraemia and sepsis
4 - all of the above
1 - initiates an immune response and upregulation of CCR5
- CCR5 is required for HIV to bind with immune cells
What is the most common test used to diagnose HIV?
1 - antibody only tests
2 - antibody/antigen tests
3 - RNA/DNA test
4 - FBC and blood film
2 - antibody/antigen tests
HIV RNA load is detected using PCR
When trying to diagnose patients with HIV, we can do antigen/antibody testing. Typically how soon can HIV antigens be detected in plasma?
1 - 1-7 days following infection
2 - 1 week following infection
3 - 2-3 weeks following infection
4 - 8-10 weeks following infection
3 - 2-3 weeks following infection
When trying to diagnose patients with HIV, we can do antigen/antibody testing. Typically how soon can HIV antibodies be detected in plasma?
1 - 1-7 days following infection
2 - 1 week following infection
3 - 2-3 weeks following infection
4 - 8-10 weeks following infection
4 - 8-10 weeks following infection
- typically because this is part of the adaptive immune response
In addition to HIV testing, which of the following tests should be performed routinely in men who have sex with men who are getting tested for HIV?
1 - Gonorrhea (GC)
2 - Chlamydia (CT)
3 - Hep B and C
4 - Syphilis
5 - all of the above
5 - all of the above
Nucleic Acid Amplification Tests (NAAT)
often used.
Which STI if contracted can increase the risk of HIV due to its ability to damage mucosal membranes?
1 - chlamydia
2 - candida albicans
3 - bacterial vaginosis
4 - herpes
1 - chlamydia
In HIV we used a term called the eclipse period. What does this mean?
1 - time until a patient presents with symptoms
2 - time until a patient dies from HIV
3 - time before HIV is detectable in blood
4 - time before AIDs is detectable in the blood
3 - time before HIV is detectable in blood
- normally lasts 10 days, but no test will be able to detect HIV
The window period in HIV is the time between transmission and production of HIV antibodies.
After this window is when the 4th generation antibody/antigen tests are able to detect HIV. How long is this window from time of infection and what level of accuracy does this test have?
1 - 45 days and >80% accuracy
2 - 55 days and >80% accuracy
3 - 55 days and >99% accuracy
4 - 45 days and 99% accuracy
4 - 45 days and 99% accuracy
- takes >45 days to accurately detect the presence of the HIV using antigen/antibody testing
- in 3rd generation tests, the window is 90 days
The 4th generation antibody/antigen tests are 99% accurate if measured after 45 days. What antigen are these tests able to detect from the HIV?
1 - p24
2 - Gp120
3 - CD4 bound Gp120
4 - CCR5
1 - p24
- a structural protein of HIV
- in 4th generation antigen/antibodies test, p24 can be detected in 14 days
If a patient tested negative at 45 days and they were a high risk for HIV, they would need to be tested again. What time point would they be tested again?
1 - 2 weeks
2 - 4 weeks
3 - 8 weeks
4 - 12 weeks
3 - 8 weeks
If a patient tests negative at 45 days for HIV, is that a definitive diagnosis?
- no
- same material must be confirmed with a 2nd test after 8 weeks
- a 3rd test is often confirmed on another occasion
In patients with a confirmed diagnosis of HIV, how may drugs are patients prescribed with one drug?
1 - 6
2 - 5
3 - 3
1 - 1
3 - 3
- called combination therapy or Antiretroviral therapy (ART) aims to stop/reduce viral replication
- generally 3 different drugs combined
- medication is lifelong