4-HIV and AIDS Flashcards
What does AIDS stand for?
Acquired Immunodeficiency Syndrome
What is AIDS?
Syndrome of opportunistic infections and malignancies secondary to severe impairment of cell-mediated immunity.
3 Ways HIV is transmitted
- sexual transmission
2 parenteral (via infected blood) - Mother to baby
name 3 blood-borne viruses
- HIV
- Hepatitis B
- Hepatitis C
What happens to CD4 count after infection of HIV
CD4 count drops drastically for 6 weeks, the body begins to recover and it increases. After a few years, it begins to drop all the way to 0.
if your CD4 count is below 200 what does it put you at risk of?
any opportunistic infection
What happens to your viral load after infection?
Viral load is very high, drops down and after a few years it begins to rise rapidly
What is seroconversion?
the time it takes from when you are infected to making the right antibodies
What does HIV do to CD4 cells?
HIV leads to a progressive decline in CD4 cells
What happens to T lymphocyte count?
goes down leading to defective cell-mediated immunity
What does defective cell-mediated immunity predispose you to ?
A wide range of opportunistic infections from:
- intracellular pathogens
- viruses
- fungal
- protozoal
- cancers (driven by viruses eg. HPV)
Give an example of an intracellular pathogen
Mycobacterium tuberculosis (TB)
give an example of an opportunistic virus?
Herpes simplex
cytomegalovirus
varicella zoster
Give an example of an opportunistic fungal infection
oral candidiasis
meningitis
Give an example of an opportunistic protozoal
Cerebral toxoplasmosis
What disease is particularly common in patients with HIV?
TB (Mycobacterium Tuberculosis)
What is Cerebral toxoplasmosis
A parasitic infection leading to lumps in the brain, oedema (fluid) surrounds the lump
What is Kaposi sarcoma?
skin cancer leading to purple lesions
How do we test for HIV?
Screening via an antibody test in which presence of HIV antibody indicates infection
Which antigen do you screen for?
p24 antigen
What 2 reasons do dentists need to know about HIV
- opportunity for early diagnosis
2. in order to protect self & other pts in healthcare setting
What to do if you have needlestick or mucous membrane exposure?
- immediate decontamination of affected area
2. “post-exposure prophylaxis” ARV
Some indicator conditions of HIV in mouth
- leukoplakia
- oral candidias (uvulla covered in white)
- kaposi sarcoma
- glossitus (red lobulated tongue)
Some oral manifestations of HIV
- angular cheilitis ( flakey redness on corners of the mouth)
- gingivitis (inflamed gums)
- xerostomia (dry tongue and mouth)
- parotitis (bilateral swelling - inflammation of parotids)
main stages of HIV lifecycle
- VIRAL ENTRY (binds to CD4 receptor on host cell)
- REVERSE TRANSCRIPTION (viral RNA transcribed to DNA
- INTEGRATION (integrates with host DNA (nucleus))
- VIRAL ASSEMBLY- (replicated) genome packaged by protease enzyme
- RELEASE OF MATURE VIRUS
What key enzymes are involved in the HIV lifecycle?
- Protease
- Integrase
- Reverse transcriptase
What is a retrovirus? e.g. hiv
virus where genes are encoded into RNA instead of DNA. (needs to be transcribed in order to replicate in host cell)
What are some typical symptoms in the acute phase of infection?
- swollen glands
- fever
- mouth ulcer
- rash
What is antiretroviral therapy?
Drugs that can block every stage of the HIV lifecycle
What is the aim of antiretroviral therapy?
to lower the viral load, giving the immune system time to recover
name 4 types of antiretroviral therapy
- entry inhibitors/ co-receptor blockers
- reverse transcriptase inhibitors
- integrase inhibitors
- protease inhibitors
why do you need to use a combination of 3 drugs?
virus easily mutates
why should you be careful with HIV therapy
risk of adverse drug interactions. Certain antiretroviral drugs can either induce or inhibit cytochrome P450 which could lead to toxic or subtherapeutic levels of other medications administered
what does it mean when patients on RV have an undetectable viral load?
it means they are not infectious, untransmissable