Immune Disorders Unit 6

Immune Disorders: Unit 6

Disseminated Intravascular Coagulation (DIC)

• DIC is classified as an underlying disorder rather than a disease.
• The severity of DIC can vary greatly, including the potential for life-threatening situations.
• Triggers for DIC include:

  • Causes massive clotting within the microcirculation.
    • Symptoms associated with DIC relate to tissue ischemia and bleeding.
    • Standard laboratory tests are utilized for assessment.
    • Treatment options will depend on the specific circumstances and underlying causes.

Assessment

• Key risk factors must be identified.
• Awareness of signs and symptoms related to thrombus formation and bleeding is critical.

Diagnosis

Diagnosis related to DIC can include:
• Risk for deficient fluid volume related to bleeding.
• Risk for impaired skin integrity stemming from ischemia or bleeding.
• Risk for imbalanced fluid volume due to excessive blood/factor component replacement.
• Ineffective tissue perfusion related to microthrombi.
• Death anxiety could be a psychological component in patients with DIC.

Planning

Nursing interventions should aim to:
• Maintain hemodynamic status throughout treatment.
• Ensure skin and oral mucosa integrity are preserved.
• Control fluid balance effectively.
• Promote adequate tissue perfusion.
• Enhance coping mechanisms for patient support.
• Strive for the absence of complications from the condition.

Interventions

Focus areas for intervention include:
• Monitoring and managing potential complications associated with DIC:

  • Renal complications

  • Pulmonary complications

  • Neurological complications

  • Integumentary system complications

  • Cardiovascular complications

  • Gastrointestinal complications

HIV/AIDS

• HIV (Human Immunodeficiency Virus) is the virus that can lead to AIDS (Acquired Immunodeficiency Syndrome), which represents the advanced stage of the infection that healthcare providers aim to prevent.

Transmission of HIV

• HIV is transmitted through body fluids containing the virus or infected CD4 lymphocytes.

  • The fluids include blood, seminal fluid, vaginal secretions, amniotic fluid, and breast milk.

  • It is crucial client education emphasizes that casual contact does not result in transmission.

  • Breaks in skin or mucosal barriers increase the risk of transmission.
    • High-risk behaviors include:

  • Sharing needles or other injection equipment.

  • Engaging in unprotected and risky sexual activities.

Prevention of HIV

Preventative measures to adopt:
• Adhere to standard precautions in all patient interactions.

  • Treat every patient as if they and the healthcare provider are potentially infectious.

  • Avoid recapping needles; if necessary, use one hand only.

  • Maintain a rigorous hand hygiene routine and practice cough etiquette.

  • Ensure safety with sharps, and use sterile injections and equipment only once.

  • Wear gloves during soiled patient care, and implement appropriate handling of linens and laundry.

  • Use a mouthpiece or bag for CPR.

Safe Sex Practices

Encouraged safe sex practices include:
• Abstaining from sharing bodily fluids.
• Limiting sexual partners to one, if possible.
• Always using latex condoms; consider alternatives for allergies, but note that lambskin does not prevent HIV transmission.
• Do not share IV drug injection equipment.

Post-Exposure Protocols

If exposed to HIV, follow these steps:
• Promptly report needle stick injuries to a supervisor.
• Identify and evaluate the source of exposure.
• Conduct a rapid HIV test for the patient, if their status is unknown.
• Prophylactic medications can be administered 2 hours post-exposure but must be within a 72-hour window.
• HIV testing should occur at baseline, and subsequent testing should occur at 6 weeks and 12 weeks.
• Check CBC and hepatic tests at two weeks after exposure.

HIV Life Cycle

  1. Binding or Attaching:

    • HIV possesses a protein on its envelope that attaches specifically to CD4 cells at a receptor site.

    • This binding activates proteins on the CD4 cell surface, allowing the HIV envelope to fuse with the CD4 membrane.

  2. Uncoating or Fusion:

    • HIV contains two single strands of viral RNA and three essential enzymes:

    • Reverse transcriptase

    • Integrase

    • Protease

    • These components are released into the CD4 T cell.

  3. DNA Synthesis:

    • The reverse transcription process creates a DNA copy from the virus’s RNA, producing a double helix that carries the instructions for viral replication.

  4. Integration:

    • HIV DNA is transported to the nucleus of the CD4 cell, where it integrates into the cell's DNA via the enzyme integrase.

    • The viral DNA then remains hidden within the CD4 cell's genetic material, which is the reason why HIV persists as a lifelong infection.

    • When the CD4 cell attempts to create new proteins, it inadvertently produces new HIV particles instead of CD4 cells.

  5. Transcription:

    • When activated, the CD4 T cell forms a single-strand messenger RNA from double-stranded DNA, eventually generating a whole new HIV virus, which can be inhibited by certain transcription inhibitors or antiviral agents.

  6. Translation:

    • Messenger RNA synthesizes chains of new proteins and enzymes, which form parts of the new HIV virus instead of components necessary for the CD4 cell.

  7. Cleavage:

    • The HIV protease enzyme cuts polyprotein chains into individual proteins, facilitating the creation of new viruses.

  8. Budding:

    • Newly formed proteins and viral RNA migrate to the infected CD4 cell membrane, exit the cell, and potentially infect additional CD4 cells upon release into the bloodstream.

Stages of HIV Disease

• The stages of HIV are primarily determined by the patient’s CD4 cell count.
• Normal CD4 count ranges from 700 to 1200 cells/mm³.

  • Primary Infection:

    • Represents the period from initial infection to the development of HIV-specific antibodies, known as the acute infection phase, or window period.

    • Symptoms fall under CDC category A (> 500 CD4 cells).

    • Patients can be infected but often do not exhibit symptoms, or may have flu-like symptoms lasting 1-2 weeks.

    • During this time, there is rapid viral replication and dissemination throughout the body, remaining undetected by typical testing methods before antibodies form.

  • Viral Set Point:

    • Represents the balance between the level of HIV and the immune response.

• Symptomatic HIV:

  • Test positive with CDC category A (> 500 CD4 cells).

  • Chronic symptomatic state begins 2-3 weeks after infection, with detectable antibodies present and sufficient immune response to fend off infectious agents.

  • Symptoms may include mild flu-like issues: fever, mild aches and pains, fatigue, nausea, vomiting, and weight loss.

  • As the virus progresses:

  • CDC category B (200-499 CD4 cells): Symptoms increase as the virus impacts more CD4 cells, thus leading to related symptoms and conditions.

Conditions Associated with HIV

• Herpes Zoster:

  • Common in HIV patients.
    • Oral Candidiasis: (thrush)
    • UTIs and Fever:
    • Diarrhea and Peripheral Neuropathy.
    • Wasting Syndrome:

  • This complex tends to initiate in CDC category B with symptoms of nausea, vomiting, diarrhea, cachexia, chronic low-grade fever, and weight loss.

  • It is not a disease process per se; it arises from loss of immune response and increased viral load associated with uncontrolled HIV.

  • Category B infections remain categorized as such even if CD4 counts improve above 500.

AIDS

• AIDS is characterized by a significantly impaired immune system, classified as CDC category C (<200 CD4 cells).

  • Once CD4 levels fall below 200, recovery to above this threshold becomes challenging.

  • CD4 levels below 100 indicate severe immune dysfunction; levels below 50 suggest a terminal prognosis where opportunistic infections are likely to become fatal.

Conditions Associated with AIDS

• Opportunistic infections become prevalent, including:

  • Candidiasis of the lungs: potentially fatal.

  • Various cancers: cervical, lung, breast, kidney, hepatic, etc.

  • HIV Encephalopathy: presents like dementia, with significant cognitive decline attributed to the virus in the CNS.

  • Kaposi Sarcoma: a life-threatening cancer associated exclusively with HIV.

  • PCP (Pneumocystis Pneumonia): often treated prophylactically with Bactrim.

Physiology Underlying Manifestations of HIV

• Fungus infections are common in nearly all HIV patients.
• Pneumocystis Carinii Pneumonia (PCP): is the most common opportunistic infection among HIV-positive individuals, with symptoms such as a non-productive cough, fever, chills, dyspnea, chest pain, possibly escalating to hypoxemia.
• Tuberculosis incidence is significantly increased in the HIV population.
• Gastrointestinal symptoms may manifest as a loss of appetite, nausea, vomiting, oral/esophageal thrush, and chronic diarrhea (with a predisposition to C. difficile).

  • Treatment Options:

    • Oral candidiasis resolved with antifungals like Mycelex, nystatin, or ketoconazole.

    • Chronic diarrhea may require octreotide acetate if severe.

    • Wasting syndrome is frequently observed in HIV, showing symptoms of >10% weight loss, chronic diarrhea, weakness, and fever of unknown origin, protein malnutrition, and muscle mass loss.

Oncology Conditions Associated with HIV

• Kaposi Sarcoma: malignancy that affects the epithelial layers of blood and lymphatic vessels, causing lesions which can develop in multiple organ systems.

  • Appearance ranges from brownish-pink to deep purple, with potential ulceration and related infection risks.
    • B-cell Lymphoma: is notably prevalent among HIV patients, severely disrupting the immune response.

  • Symptoms include weight loss, night sweats, fever, and CBC abnormalities.

Neurologic Effects of HIV

• HIV exerts profound effects on cognitive, motor, and executive functions, as well as attention and visuospatial processing.
• HIV Encephalopathy: entails progressive cognitive, behavioral, and motor decline, often irreversible, resembles dementia.

  • Early signs include memory deficits, headaches, difficulty concentrating, confusion, psychomotor slowing, apathy, and ataxia.

  • Progression leads to global cognitive impairments, delayed verbal responses, a vacant stare, spastic paraparesis, hyperreflexia, psychosis, hallucinations, and tremors, eventual death may occur due to complications.
    • Infection with Cryptococcus neoformans can lead to meningitis, with symptoms like mental confusion progressing toward blindness, aphasia, weakness, paresis, and death.

Management of HIV

• HIV Testing:

  • Rapid test: a negative result indicates no infection; if positive, follow with an ELISA test for confirmation, which is more complex and time-consuming.

    • If ELISA is negative, the process stops; if positive, a Western Blot test confirms diagnosis, being definitive and with fewer false negatives.
      • Recent advancements have introduced various testing modalities, including at-home tests.

Treatment of HIV

• Treatments and protocols continue to evolve with ongoing research and resource availability.
• HIV is now perceived as a manageable disease, comparable to conditions like diabetes.

  • Regular monitoring of lab results, such as viral load and CD4 count, is essential due to the rapid mutation rate of HIV, necessitating timely adjustments in treatment protocols.

Continued Treatment of HIV

• The use of anti-retroviral agents often involves a combination, or "cocktail," of drugs targeting different stages in the virus's life cycle, thus preventing replication in CD4 cells.

  • Classes of anti-retroviral agents include:

    • Nucleotide Reverse Transcriptase Inhibitors (NRTIs)

    • Non-nucleotide Reverse Transcriptase Inhibitors (NNRTIs)

    • Protease Inhibitors

    • Fusion Inhibitors
      • Combination therapy can be established with regimens like daily oral medications or monthly injections.

HIV Medication Side Effects & Compliance

• Common side effects of HIV medications can encompass:

  • Dyslipidemia

  • Hyperglycemia

  • Peripheral neuropathy

  • Myopathy

  • Cardiomyopathy

  • Pancreatitis

  • Lipodystrophy
    • In contemporary practice, mortality from AIDS-related complications has significantly diminished, with patients now succumbing to common conditions such as cardiac issues and strokes due to improved medication compliance.