IMMUNODEFICIENCY 1.1 Flashcards
AIDS-MANIFESTATIONS
The final and most severe stage of Human Immunodeficiency Virus (HIV) infection.
ACQUIRED IMMUNODEFICIENCY SYNDROME (AIDS)
It is characterized by profound immunosuppression, which leads to opportunistic infections, malignancies, and a variety of other clinical conditions.
ACQUIRED IMMUNODEFICIENCY SYNDROME (AIDS)
HIV primarily targets the immune system, specifically ________________, leading to their gradual depletion and the weakening of the immune response.
CD4+ T lymphocytes (also known as Thelper cells)
They coordinate the immune response by signaling other cells, such as B cells (which produce antibodies), cytotoxic T cells (which kill infected cells), and macrophages (which engulf pathogens).
CD4+ T lymphocytes (also known as Thelper cells)
It is a retrovirus that carries its genetic material in the form of RNA. The virus is spherical and contains two copies of single-stranded RNA, enveloped in a lipid bilayer derived from the host cell membrane.
HIV
Embedded in this envelope are glycoproteins (gp120 and gp41) crucial for the virus’s ability to infect host cells.
HIV STRUCTURE AND ENTRY INTO HOST CELLS
Binds to the CD4 receptor on T-helper cells, macrophages, and dendritic cells. This binding is a key step in the virus’s ability to enter the host cell.
GP120
HIV STRUCTURE AND ENTRY INTO HOST CELLS
Facilitates the fusion of the viral envelope with the host cellmembrane, allowing the viral RNA to enter the cell
GP41
REPLICATION CYCLE OF HIV
1.Binding
2.Fusion
3.Reverse Transcription
4.Integration
5.Replication
6.Assembly
7.Budding
REPLICATION CYCLE OF HIV:
HIV binds to the surface of the host cell (CD4 cell).
BINDING
REPLICATION CYCLE OF HIV:
The HIV fuses with the cell membrane of the host cell allowing the HIV contents including RNA, reverse transcriptase, integrase, and other proteins to enter the cell.
FUSION
REPLICATION CYCLE OF HIV:
Inside the cell, HIV RNA is converted into DNA using reverse transcriptase.
REVERSE
TRANSCRIPTION
REPLICATION CYCLE OF HIV:
Integrase enzyme allows HIV DNA to be integrated into the host DNA.
INTEGRATION
REPLICATION CYCLE OF HIV:
HIV can now produce long chains of HIV proteins which can be used to build more HIV
REPLICATION
REPLICATION CYCLE OF HIV:
HIV proteins and RNA move to surface of cells and are assembled into immature HIV.
ASSEMBLY
REPLICATION CYCLE OF HIV:
Immature HIV is pushed out of the cell and proteases activate immature into mature infectious HIV
BUDDING
FOUR CATEGORIES OF HIV INFECTION
- Primary Infection
- HIV Asymptomatic (CDC Category A)
- HIV Symptomatic (CDC Category B)
- AIDS (CDC Category C)
FOUR CATEGORIES OF HIV INFECTION:
- Acute/Recent HIV Infection, Acute HIV Syndrome
- Occurs within 2 to 4 weeks after exposure to the virus.
Primary Infection
FOUR CATEGORIES OF HIV INFECTION:
- CD4+ T Cell Count:Despite normal levels being between 500 to 1,500 cells/mm³, there is often a sharp, temporary drop during acute infection.
- Many people experience flu-like symptoms such as fever, rash, swollen lymph nodes, sore throat, and muscle aches. However, some individuals may not experience noticeable symptoms at this stage
Primary Infection
FOUR CATEGORIES OF HIV INFECTION:
- This stage can last for several years (an average of 8-10 years without treatment), but this varies from person to person.
- Also known as the clinical latency stage, this period is characterized by relatively stable levels of CD4+ T cells. The immune system is still strong enough to fend off major infections, and many individuals do not show any HIV-related symptoms.
HIV Asymptomatic (CDC Category A)
FOUR CATEGORIES OF HIV INFECTION:
- CD4+ T Cell Count: CD4+ T cell counts remain above 500 cells/mm³. Although the virus is still replicating, it is doing so at lower levels than in the acute stage. CD4+ T cells gradually decline over time, but the person’s immune system is largely intact during this stage.
- Individuals may not experience noticeable symptoms and can often continue with their daily lives without knowing they are infected unless tested for HIV.
HIV Asymptomatic (CDC Category A)
FOUR CATEGORIES OF HIV INFECTION:
- This stage occurs as the immune system weakens, typically following the asymptomatic stage if antiretroviral therapy (ART) is not initiated.
- At this point, the immune system has become compromised, and the person begins to develop HIVrelated symptoms.
HIV Symptomatic (CDC Category B)
FOUR CATEGORIES OF HIV INFECTION:
CD4+ T Cell Count: CD4+ T cell counts fall to between 200 and 499 cells/mm³. The drop in CD4+ T cell count reflects significant damage to the immune system, increasing the risk of infections and other complications.
HIV Symptomatic (CDC Category B)
FOUR CATEGORIES OF HIV INFECTION:
Category B symptoms: Those that are directly attributable to HIV infection or indicative of a defect in cell-mediated immunity.
- Oropharyngeal candidiasis (oral thrush)
- Cervical dysplasia or carcinoma in situ
- Herpes zoster (shingles) involving at least two distinct episodes or more than one dermatome
- Constitutional symptoms such as fever (38.5°C or higher) or diarrhea lasting longer than one month
- Peripheral neuropathy
FOUR CATEGORIES OF HIV INFECTION:
- Without treatment, the progression to this stage typically occurs about 10 years after initial infection, though this varies based on the person’s health and treatment status.
- It is the most severe stage of HIV infection and is characterized by a severely weakened immune system.
AIDS (CDC Category C)
FOUR CATEGORIES OF HIV INFECTION:
This is the point at which HIV has caused such significant immune system damage that the person is vulnerable to opportunistic infections and certain types of cancers, which are rare in people with healthy immune systems.
AIDS (CDC Category C)
FOUR CATEGORIES OF HIV INFECTION:
CD4+ T Cell Count: CD4+ T cell counts fall below 200 cells/mm³, a critical threshold that defines the diagnosis of AIDS. Normally, the immune system cannot adequately protect against infections and illnesses at this point.
AIDS (CDC Category C)
FOUR CATEGORIES OF HIV INFECTION: | AIDS (CDC Category C)
Opportunistic Infections and AIDS-Defining Illnesses:
- Pneumocystis jirovecii pneumonia (PCP)
- Kaposi’s Sarcoma (KS)
- Toxoplasmosis
- Cytomegalovirus (CMV)
- Tuberculosis (TB)
Opportunistic Infections and AIDS-Defining Illnesses:
A fungal infection that causes severe pneumonia.
Pneumocystis jirovecii pneumonia (PCP)
Opportunistic Infections and AIDS-Defining Illnesses:
A cancer that causes patches of abnormal tissue to grow under the skin or in the lining of the mouth, nose, and other organs.
Kaposi’s Sarcoma (KS)
Opportunistic Infections and AIDS-Defining Illnesses:
A parasitic infection affecting the brain
Toxoplasmosis
Opportunistic Infections and AIDS-Defining Illnesses:
A viral infection that can affect the eyes, lungs, or digestive tract.
Cytomegalovirus (CMV)
Opportunistic Infections and AIDS-Defining Illnesses:
The most common opportunistic infection associated with HIV/AIDS worldwide.
Tuberculosis (TB)
RISK FACTORS OF AIDS
FOR BOTH TRANSMITTED AND NOT
TRANSMITTED
* Unprotected sex
* Blood Transfusion
* Drug Injection
* Accident by needles
* Pregnancy
NOT TRANSMITTED
* Kissing
* Touching
* Mosquito bite
* Food & drinks
* Toilets
Main Symptoms of Acute HIV Infection
SYSTEMIC:
* Fever
* Weight Loss
CENTRAL:
* Malaise
* Headache
* Neuropathy
MOUTH:
* Sores
* Thrush
* Pharyngitis
LYMPH NODES:
* Lymphadenopathy
ESOPHAGUS:
* Sores
MUSCLES:
* Myalgia
LIVER AND SPLEEN:
* Enlargement
SKIN:
* Rash
GASTRIC:
* Nausea
* Vomitting
MAIN SYMPTOMS OF AIDS
CENTRAL:
* Encephalitis
* Meningitis
EYES:
* Retinitis
LUNGS:
* Pneumocystis Pneumonia
* Tuberculosis (multiple organs)
* Tumors
SKIN:
* Tumors
GASTROINTESTINAL:
* Esophagitis
* Chronic Diarrhea
* Tumors
Wasting Syndrome is also known as…
Cachexia
