HIV/Atypical Mycobacterium Lecture

Question 1

A unique type of virus (a retrovirus)
Invades the helper T cells (CD4 cells) in the body of the host (defense mechanism of a person)

*preventable, manageable but NOT curable

Answer 1

HIV

Question 2

RNA virus
Retrovirus, subfamily lentivirus
Cytopathic
CD4 + lymphocyte is primary target but monocyte/macrohages also express CD4 and become infected

Answer 2

HIV

Question 3

type 1= most common

type 2=West Africa, less aggressive

Answer 3

HIV

Question 4

Disease limits the body’s ability to fight infection due to markedly reduced helper T cells.
Patients have a very weak immune system (defense mechanism)
Patients predisposed to multiple opportunistic infections leading to death.

Answer 4

AIDS

Question 5

Positive HIV who have ever had a CD4 lymphocyte count below 200 cells/mcL or a CD4 lymphocyte percentage below 14%

Answer 5

AIDS

Question 6

• Icosahedral (20 sided), enveloped virus of the lentivirus subfamily of retroviruses.
• Retroviruses transcribe RNA to DNA.
• Two viral strands of RNA found in core surrounded by protein outer coat.

Answer 6

HIV

Question 7

• Outer envelope contains a lipid matrix within which specific viral glycoproteins are imbedded.
• These knob-like structures responsible for binding to target cell.

Answer 7

HIV

Question 8

• direct cytopathic effects
• bystander (syncytia formation)
• failure to regenerate cells (bone marrow infect, thymus infexn)
• autoimmunity

Answer 8

Pathology of CD4 plus lymphocyte depletion

Question 9

Sexual
Vertical – mother to child, perinatal
Parenteral – injection drug users
Transfusion
Nosocomial

Answer 9

HIV modes of transmission

Question 10

Blood products
Semen
Vaginal fluids

Answer 10

HIV transmission thru bodily fluids

Question 11

• Short, flu-like illness - occurs one to six weeks after infection
• Mild symptoms
• Infected person can infect other people

Which HIV stage?

Answer 11

Stage 1

Question 12

• Lasts for an average of ten years
• This stage is free from symptoms
• There may be swollen glands
• The level of HIV in the blood drops to low levels
• HIV antibodies are detectable in the blood

Which HIV stage?

Answer 12

Stage 2

Question 13

After a period of latency lasting up to 10 years viral replication is triggered and occurs at high rate.
CD4 cell may be destroyed in the process, body attempts to replace lost CD4 cells, but over the course of many years body is unable to keep the count at a safe level.
Destruction of large numbers of CD4 cause symptoms of HIV to appear with increased susceptibility to opportunistic infections, disease and malignancy.

Answer 13

Viral replication during latent stage (stage 2)

Question 14

• HIV continues to reproduce, CD4 count gradually declines from its normal value of 500-1200.
• Once CD4 count drops below 500, HIV infected person at risk for opportunistic infections.
• The following diseases are predictive of the progression to AIDS:
• persistent herpes-zoster infection (shingles)
• oral candidiasis (thrush)
• oral hairy leukoplakia
• Kaposi’s sarcoma (KS)

Answer 14

Clinical latency period

Question 15

SYMPTOMATIC
The immune system deteriorates
Opportunistic infections and cancers start to appear.

Which HIV stage?

Answer 15

Stage 3

Question 16

HIV to AIDS
*The immune system weakens too much as CD4 cells decrease in number.

Which HIV stage?

Answer 16

Stage 4

Question 17

Generalized lymphadenopathy
Unexplained thrush
New severe psoriasis, skin disorder
Unexplained weight loss
Unexplained thrombocytopenia, etc
Neurologic disease (CNS/peripheral)
Recurrent bacterial pneumonia
Chronic diarrhea

Answer 17

Clinical presentation of HIV

Question 18

Bacterial infections
Tuberculosis (TB)
Herpes Simplex
Herpes Zoster
Vaginal candidiasis
Hairy leukoplakia
Kaposi’s sarcoma

CD4 under…

Answer 18

500

Question 19

Pneumocystic carinii
Toxoplasmosis
Cryptococcosis
Coccidiodomycosis
Cryptosporiosis
Non hodgkin’s lymphoma

CD4 under…

Answer 19

200

Question 20

Antibody testing:

• ELISA/Western Blot antibody test
• Rapid blood/oral test
• Home HIV test kit

Viral detection:

• Culture
• RNA PCR (viral load)

Answer 20

Ways to diagnose HIV

Question 21

Orasure:
The only FDA approved HIV antibody.
As accurate as blood testing
Draws blood-derived fluids from the gum tissue.
NOT A SALIVA TEST!

Answer 21

Oral testing for HIV

Question 22

4th generation (HIV1 and HIV2 IgG and IgM plus HIV1 p24 Ag)

Answer 22

initial test for HIV!!!!!!!

more accurate, faster and less expensive

Question 23

What is the confirmatory test (after 4th gen HIV-1 and HIV-2 IgG and IgM plus HIV-1 p24 Ag)?

Answer 23

Multispot test!

Question 24

If multi-spot test is positive for HIV-1, order….

Answer 24

QUANTITATIVE HIV-1 PCR

Question 25

Regimens must consists of ___ or more active agents from multiple medication classes

Answer 25

3

Question 26

For the greatest chance of success, post-exposure prophylaxis must begin ASAP..at a minimum within _____ of exposure

Answer 26

72 hours