58:50 DAY TWO part 2
Pathophysiology of HIV
Definition of HIV
HIV (Human Immunodeficiency Virus) is an RNA virus.
It is classified as a slow retrovirus, indicating that it reverses from RNA to DNA.
Mechanism of Action
HIV uses reverse transcriptase to convert its RNA into DNA.
The viral DNA is then integrated into the host's DNA, allowing the virus to replicate using the host's cellular machinery.
Entry Points
HIV enters the body through mucosal tissues.
It specifically targets CD4 cells, which are a subset of T helper cells involved in immune responses.
CD4 Cells and Their Importance
CD4 cells are crucial to the immune system.
A normal CD4 count ranges from 500 to 1,500 cells/mm³.
A CD4 count of less than 200 cells/mm³ indicates progression to AIDS (Acquired Immunodeficiency Syndrome).
Monitoring CD4 count helps evaluate immune system functionality and progression of HIV.
HIV Replication and Impact on Immune System
Replication Process
HIV can remain dormant within its host or become active, leading to the production of new HIV particles.
Viral particles mature with the help of protease and eventually bud off from the CD4 cell, which leads to cell death.
Consequences of HIV Infection
Progressive loss of CD4 cells results in immune suppression, making individuals susceptible to opportunistic infections.
As the CD4 count decreases, the risk of developing serious infections increases.
Viral Load
High viral load refers to the quantity of HIV present in the body.
A high viral load increases the risk of transmission and aids in the destruction of CD4 cells.
Viral load may initially be high following infection, even in asymptomatic individuals.
Disease Progression
Stages of HIV Infection
Early stage: High viral load and potential flu-like symptoms (e.g., fever, night sweats, fatigue).
Intermediate stage: Clinically asymptomatic but can still transmit the virus.
Later stages lead to severe immune suppression and manifestation of AIDS-related infections.
Long-term Non-progressors
Some individuals may remain stable for years, benefiting from genetic factors that control the virus's replication.
Symptomatic HIV Disease
Begins when CD4 count drops below 500 cells/mm³. Symptoms may affect daily activities due to fatigue, weight loss, and more.
Symptoms include persistent lymphadenopathy, oral thrush, shingles, and neurological symptoms can occur.
Testing and Diagnosis
Types of HIV Tests
Antigen-antibody tests: Commonly used; detects both HIV antigen and antibodies.
Nucleic acid tests (NAT): Used to directly detect the presence of the virus in the blood.
Antibody tests: Detects antibodies alone, which may give negative results if performed too early in the infection.
Window Period
The time frame in which antibody tests may yield false negatives, varying from 10 to 90 days post-exposure.
Monitoring Disease Progression
Key Indicators
CD4 count and viral load are crucial for assessing immune function and disease progression.
CD4 count typically decreases as viral load increases, indicating worsening immune function.
Prophylaxis for Opportunistic Infections
Patients with CD4 counts below 200 cells/mm³ are at high risk for pneumonia and other infections.
Prophylactic medication may be introduced to prevent these infections.
Treatment and Management
Antiretroviral Therapy (ART)
ART employs three or more medications to decrease viral load and protect CD4 cells.
Medication adherence is crucial to prevent drug resistance and improve health outcomes.
Importance of Education
Patients need education about their medication regimens to ensure adherence and understanding of their disease.
Complementary and Alternative Therapies
Integration of Therapies
Patients are encouraged to discuss any complementary therapies (e.g., herbal remedies, acupuncture) with their healthcare team to ensure safe and effective care.
Prevention and Support
Prevention Strategies
Safe sex practices, needle exchange programs, and community resources are important for reducing transmission.
Emotional and Social Support
Emotional counseling and support groups are vital for helping patients cope with their diagnosis and treatment.
A transdisciplinary approach involving various healthcare professionals can enhance support for patients.
Palliative Care in HIV
When to Introduce Palliative Care
Typically introduced in the later stages of HIV/AIDS, focusing on comfort and quality of life alongside ongoing ART.
Role of Palliative Care
Addresses physical, emotional, social, and spiritual needs of the patient and their families.