Ch 32: Human Immunodeficiency Virus (HIV)

Human Immunodeficiency Virus (HIV) Definition and Overview

• Human Immunodeficiency Virus (HIV) is defined as a virus that attacks the white blood cells of the human body, specifically the $CD4\,T$ cells. This attack results in the weakening of the immune system.

• The history and classification of the virus distinguish between two primary types:

  • HIV-1: This variant is more common worldwide. It is characterized as being more easily transmissible and is more likely to be progressive than the second variant.

  • HIV-2: This variant is less common and generally less progressive than HIV-1.

Transmission Mechanisms and CDC Categories

• HIV transmission occurs through exposure to specific bodily fluids containing the virus. It is critical to note that transmission is determined by exposure to these fluids rather than by an individual's lifestyle or sexual orientation. The fluids include:

  • Blood

  • Semen

  • Breast Milk

  • Vaginal secretions

• The Centers for Disease Control and Prevention (CDC) has established five primary transmission categories utilized for diagnosis:

  • Male to Male sexual contact.

  • Injection drug use.

  • Heterosexual (male to female) contact.

  • Mother to child (perinatal) transmission.

  • Other causes, which include blood transfusions and factors currently classified as unknown causes.

Pathophysiology and Viral Life Cycle

• The primary pathological effect of HIV is the destruction of immune cells.

• HIV is classified as a Retrovirus. In these viruses, the standard process of genetic transcription is reversed. Instead of the normal biological flow of DNA to RNA, HIV performs transcription from RNA to DNA.

• The life cycle and structure of HIV involve the following:

  • The virus is spherical in shape and possesses two specific protein markers.

  • These protein markers allow the virus to attach to T4 or $CD4$ helper cells and macrophages.

  • This attachment and subsequent infection cause the immune response of the patient to become severely impaired.

• The disease progresses through stages, with the third stage being characterized by the experience of opportunistic infections resulting from low T cell counts.

• A diagnosis of Acquired Immunodeficiency Syndrome (AIDS) is confirmed when $CD4$ cell levels fall below the threshold of $200\,cells/mm^3$. At this stage, the levels of the virus in the blood are extremely high.

Clinical Manifestations and Symptomatology

• Initial symptoms of HIV are often described as vague. The most common signs and symptoms include persistent fatigue and weight loss.

• Wasting syndrome is experienced by almost all patients with HIV. This syndrome is a direct result of significant weight loss and malnutrition.

Diagnostic Testing and Laboratory Analysis

• Enzyme Immunosorbent Assay (ELISA):

  • This is utilized as the initial test for HIV.

  • It is a laboratory test that measures antibodies, antigens, and protein hormones within a liquid sample.

• HIV RNA (Viral Load) Test:

  • This test is used to confirm the diagnosis and verify the presence of an active infection.

• $CD4+ T$ Cell Count:

  • Monitoring this count is critical for assessing the progression of the disease toward AIDS.

  • A count of less than $200\,mm^3$ serves as the diagnostic threshold for AIDS.

Comprehensive Nursing Assessments

• Vital Signs Assessment:

  • Nurses must monitor for fever, tachycardia, respiratory changes, and oxygen ($O_2$) saturation.

  • A specific nursing care requirement is to check the patient's temperature daily because of the underlying autoimmune deficiency.

• Monitoring for Opportunistic Infections:

  • Signs to watch for include cough, shortness of breath (SOB), persistent diarrhea, fever, night sweats, oral thrush, unusual skin lesions, headaches, confusion, and changes in vision.

• Immune and Medication Status:

  • Nurses must review the patient's $CD4$ count and viral load regularly.

  • Assessment of Antiretroviral Therapy (ART) is essential, focusing on patient adherence, identifying missed doses, monitoring for side effects, and checking for potential drug interactions.

• Respiratory and Skin Assessment:

  • Respiratory checks include evaluating lung sounds, cough, sputum production, dyspnea, and $O_2$ levels.

  • Skin and mucous membranes should be inspected for rashes, lesions, wounds, oral ulcers, and thrush.

  • Identification of purple or brown lesions is a critical nursing observation as these are indicative of Kaposi's Sarcoma.

• Gastrointestinal and Nutritional Assessment:

  • Nurses must track weight loss, appetite, nausea, vomiting, diarrhea, and the patient's ability to swallow. Overall hydration and nutrition status must be maintained.

• Neurological and Psychological Assessment:

  • Neurological monitoring covers orientation, cognition, headaches, weakness, numbness or tingling, and any changes in mental status. Monitoring adherence to antiviral medications is a related nursing priority.

  • Psychological assessment includes screening for depression, anxiety, and the impact of stigma. Nurses should evaluate the patient's coping mechanisms, support systems, housing resources, and safety. A key intervention is encouraging patients to join support groups.

• History and Risk Assessment:

  • Social and medical history should include sexual history, History of Sexually Transmitted Infections (STIs), and exposure to injection drugs. Other relevant screenings include Hepatitis and Tuberculosis (TB).

• Pain and End-of-Life Care:

  • Assessment of fatigue and pain should focus on location, severity, and the impact on daily activities. In end-of-life care, routine analgesia (pain medication) is provided.

Patient Teaching and Infection Control

• Patients must be educated on the high likelihood of recurring bacterial infections and the resulting importance of strict infection control practices.

• Pneumocystis Pneumonia is an expected complication that requires specific preventative measures. If detected, it necessitates further and immediate medical intervention.

• Education on medication adherence is paramount; patients must understand the vital importance of taking their antiviral medications as prescribed.

• Personal and hand hygiene practices should be taught and reinforced to minimize the risk of secondary infections.