HIV RELATED LECTURES[129/130][127/128][074][075][073][126] Flashcards
What happens to the CD4 count and the viral load as HIV progresses?
CD4 count: decreases
HIV viral load: increases
What is a low CD4 count associated with?
An increase in opportunistic infections and tumors
Below what CD4 count do most AIDS diagnoses occur?
CD4 less than 200
what interventions can be done to prevent mother to child transmission?
Antiretroviral therapy
avoidance of breastfeeding
post exposure prophylaxis for baby (4 weeks on HAART - Highly active antiretroviral therapy)
what cancer is associated with HIV?
Kaposi’s sarcoma
what do we mainly use for monitoring and follow up of an HIV patient?
CD4 count and viral load every 3 months
what is the main aim of HAART?
- does not cure, but extend life and increase QOL
-suppresses HIV replication enough to have undetectable plasma viral load by 24weeks of treatment. Undetectable= untransmissible. - immune system is able to recover well on HAART, hence CD4 count increases which reduces opportunistic infections and certain malignancies
What family and genus does the HIV virus belong to?
Family: Retroviridae
Genus: Lentiviruses (lenti: slow, denoting slow progression of disease)
What family and genus does the HIV virus belong to?
Family: Retroviridae
Genus: Lentiviruses (lenti: slow, denoting slow progression of disease)
What family and genus does the HIV virus belong to?
Family: Retroviridae
Genus: Lentiviruses (lenti: slow, denoting slow progression of disease)
what enzyme does HIV possess that allows it to transcribe from ssRNA to DNA in order to integrate its genetic material into host cells?
Reverse transcriptase.
what are the 3 major structural genes possessed by HIV virion?
- env gene, coding for:
env gp120: responsible for viral binding to host cells
env gp41: mediates fusion of virus with host cell membrane - gag gene, coding for gagp24 (core protein)
- Pol genes (polymerase) coding for:
reverse transcriptase, protease, integrase
in what year was HIV identified?
1985
what is another name for HAART
CART (Combined antiretroviral therapy)
name a few conditions that happen as a result of immunodeficiency from the HIV infection
- cryptococcal meningitis
- kaposi’s sarcoma
-oesophageal candida - herpes (Shingles)
How many types of HIV viruses are there?
HIV-1: INFECTS HHUMANS. the most widespread type is group M (can also be split into subgroups A-J, B being predominant in the west)
HIV-2: Simian immunodeficiency virus, infects non-humans (non pathogenic in their host species of origin)
Name the 3 clinical stages of an HIV infection
- Early, acute stage: primary HIV infection. inital rapid rise in plasma viremia, massive decrease ofCD4 cells in tissue, with only a slight decrease in blood.High levels of innate immune activation and inflammation. Non specific, flu like symptoms: myalgia, headache, rash, fever, fatigue, lymphadenopathy, GI symptoms. Self limiting, 2-4 weeks. Resolution of symptoms correlates with increase in blood CD8+ count, and a decline of plasma viremia coincides with it.
- Clinical latency stage:
minimal to know symptoms. CD4 count slowly decreases. Towards the end of this period, patient gets constitutional symptoms of immunodeficiency start to show. - OVERT AIDS:
severe constitutional symptoms, opportunistic infections, neoplasms, and eventually, death.
state the steps of replication of HIV in CD4 cells
- binding to CD4
- fusion
- reverse transcription
- integration of viral DNA into human DNA
- Replication
- Assembly to form cell with HIV genetic material
- Budding, goes to infect more and more cells.
HIV gp120 uses what on the T cell as a receptor to bind to it?
CD4.
What on the T cell is used as a coreceptor for HIV?
CCR5 (Chemokine receptor 5), however some HIV viruses use CXCR4 (chemokine receptor 4 instead).
HIV tends to use CCR5 early in the course of the disease then use CXCR4 as the patient progresses to AIDS.
Name the 6 classes of anti-HIV drugs.
- entry inhibitors
- fusion inhibitors
- Nucleoside/ Nucleotide reverse transcriptase inhibitors
- Non Nucleoside/ Nucleotide reverse transcriptase inhibitors
- Integrase inhibitors
- Protease inhibitors