HIV/AIDS for NP
HIV/AIDS for the Nurse Practitioner Licensing Exam
HIV/AIDS Overview
- Transmission:
- Sexual Contact: Main route, with increased risk during unprotected sex and in receptive anal intercourse.
- Blood Exposure: Sharing needles among injection drug users and accidental needlestick injuries.
- Vertical Transmission: From mother to child during pregnancy, delivery, or breastfeeding if untreated.
- Pathophysiology:
- HIV is an RNA retrovirus targeting CD4+ T cells, which are critical to immune defense.
- The virus binds to CD4 and co-receptors (CCR5 or CXCR4), enters the cell, and integrates into the host genome, establishing a persistent infection.
- Over time, HIV depletes CD4 cells, weakening the immune system and leading to AIDS if untreated.
Clinical Stages
- Acute Retroviral Syndrome:
- Occurs 2–4 weeks after exposure, with flu-like symptoms: fever, sore throat, rash, and lymphadenopathy.
- Diagnosis in early infection is through HIV RNA PCR, as antibodies may not yet be detectable.
- Chronic HIV Infection:
- A prolonged latent phase with gradual CD4 decline; mild symptoms like oral candidiasis may appear.
- Untreated, the infection eventually progresses to AIDS.
- AIDS:
- Defined by CD4 <200 cells/µL or AIDS-defining illnesses like Pneumocystis pneumonia and Kaposi sarcoma.
Diagnosis and Monitoring
- Screening:
- Antigen/Antibody Combination Test: Detects both antibodies and p24 antigen, enabling early detection.
- HIV RNA Testing: Used for suspected acute HIV infection when antibody levels are still low.
- Monitoring:
- CD4 Count: Assesses immune function and guides prophylaxis.
- Viral Load: Monitors ART effectiveness and viral replication.
Treatment and Prevention
- Antiretroviral Therapy (ART):
- Goal: Suppress viral replication, prevent disease progression, and reduce transmission.
- Common Regimen: Combination of NRTIs (e.g., tenofovir, emtricitabine) with an INSTI (e.g., dolutegravir).
- Prophylaxis for Opportunistic Infections:
- PCP: TMP-SMX when CD4 <200 cells/µL.
- MAC: Azithromycin when CD4 <50 cells/µL.
- Pre-Exposure and Post-Exposure Prophylaxis (PrEP and PEP):
- PrEP: Daily tenofovir/emtricitabine for high-risk HIV-negative individuals.
- PEP: 28-day ART course after potential HIV exposure, ideally started within 72 hours.
Key Points
- HIV targets CD4+ cells, weakening immune defenses and leading to AIDS if untreated.
- Transmission occurs through sexual contact, blood exposure, and vertical transmission.
- ART is essential to control viral replication, prevent progression, and reduce transmission.
- PrEP and PEP are preventive measures for individuals at risk or following potential exposure.
- Prophylaxis for opportunistic infections is based on CD4 count, with TMP-SMX and azithromycin commonly used.