HIV and AIDS - presentation

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HIV and AIDS - presentation
2014-04-17 05:21:04
pharmacology HIV antiretrovirals

HIV and Aids as taught by Ronnie Chan
Show Answers:

  1. What does HIV and AIDS stand for?
    • HIV (Human Immunodeficiency virus)
    • AIDS (acquired immunodeficiency syndrome)
  2. What is the HIV and what does it contain?
    • An RNA retrovirus - subfamily Lentivirus
    • Contains 2 copies of RNA
    • Enzymes: Reverse transcriptase
    • Integrase
    • Protease
    • Two major envelope proteins: GP120 (docking)
    • GP41 (transmembrane)

    Requires host DNA to replicate and produce proteins
  3. What are the types of HIV and what are there properties?
    • Types           HIV 1           HIV 2
    • virulence      High             Low
    • infectivity     High             Low
    • prevalence  Most common Uncommon, found in
    •                   globally          West Africa
    • binding site  CCR5            CXCR4 co-receptor
    •                    co-recptor
  4. Common HIV host cell and why?
    • CD4 T cells are most commonly infected. High affinity for gp120.
    • Acute phase death - cytopathic damage by virus

    • Chronic death - chronic activation of T cells
    • inhibition of thymic output of T cells
    • suppression of the bone marrow
    • destruction of lymph-node architecture
    • low-level ongoing infection of memory CD4 T cells
  5. What are the methods of transmission?
    Sexual - anal, vigina (homo=men, hetro=women (most common))

    Percutaneous - rarely transfusions, needle sharing, needle stick

    Vertical - transplacental, periparium, breast milk ingestion
  6. What are the stages associated with HIV infection?
    Stage 1 - Primary - cold or flu-like symptoms. Antibody test usualy negative, becomes positive after 3-6months (6m = 95%) seroconversion.

    Stage 2 - Asymptomatic - average duration 10 years. Symptom free, may have swollen glands.

    Stage 3 - Symptomatic - immune system deteriorates. CD4 count below 500 = risk of opportunistic infections.

    Stage 4 - HIV to AIDS. Advanced HIV when CD4 count below 200. Need AIDS defining illness or infection.
  7. What tests are available for HIV testing?
    • Screening tests - ELISA or EIA - rapid testing - whole blood, plasma, saliva or urine test.
    • Confirmatory tests - Western Blot analysis, RT-PCR)

    Rapid HIV antibody test - sensitive and specific 99%. Results on 5 to 40 minutes

    HIV viral load - first choice for diagnosing acute HIV

    HIV p24 antigen - first antigen to be elevated in acute HIV. Can be used for acute diagnosis
  8. What classes of drug are available to reduce the progression of HIV?
    • RTI - Reverse-Transcriptase Inhibitors
    • PI - Protease Inhibitors
    • Integrase Inhibitors
    • Entry (fusion) Inhibitors
    • Maturation Inhibitors (new class)
  9. What are the three forms of RTI?
    • - NARTI or NRTI - Nucleoside analogue reverse-transcriptase inhibitors.
    • - NtARTI or NtRTI - Nucleotide analogue reverse-transcriptase inhibitors
    • - NNRTI Non-nucleoside reverse-transcriptase inhibitors
  10. What are the main reasons for HAART?
    • Highly active antiretroviral therapy is used to:
    • reduce the toxic effects of the drugs,
    • to increase the time it takes for resistance to occur,
    • restore sensitivity in some cases, 
    • slow the progression of the disease,
    • fewer opportunistic infections,
    • improve or stabilise immunity,
    • suppress HIV replication.
  11. What is a typical combination therapy?
    NNRTI OR PI OR Integrase Inhibitor

    AND 2 NRTIs