Midterm exam

HIV Overview

• Transmission:

  • HIV is transmitted through body fluids such as blood, seminal fluid, vaginal secretions, amniotic fluid, and breast milk.

• Risk Factors (RF):

  • Sharing of used drug equipment

  • Sexual contact with infected individuals

  • Infants born to or breastfed by mothers with HIV

  • Organ transplants or blood transfusions from HIV-positive donors.

Stages and Symptoms of HIV Infection

• Stages of HIV Infection:

  1. Early Infection:

     • Symptoms include flu-like symptoms appearing within 2-4 weeks post-exposure.

     • Tests may show negative for antibodies initially.

  2. Viral Set Point:

     • Equilibrium between HIV levels and immune response; chronic asymptomatic stage.

     • CD4 counts between 200-499 cells/mm³; no opportunistic infections.

  3. AIDS (CD4 < 200 cells/mm³):

     • Characterized by the presence of opportunistic infections such as cancers (e.g., Kaposi's sarcoma).

     • Other symptoms may include pneumonitis, loss of appetite, and diarrhea.

Diagnostics and Treatment

• Diagnostics:

  • Blood Tests including:

    • Immunoassays for HIV antibodies and antigens.

    • Differentiation assays for HIV-1 and HIV-2.

    • Nucleic acid amplification tests for direct detection of the virus.

  • CD4 Cell Counts:

    • Normal range is 500-1500 cells/mm³.

• Antiretroviral Therapy (ART):

  • Initiated within 72 hours after exposure to limit replication.

  • A typical regimen includes 2-3 drugs taken for 28 days.

  • Main drugs include:

    • Abacavir: Antiviral, taken without food; monitor for hypersensitivity.

    • Zidovudine: Note potential for bone marrow suppression.

Mechanism of HIV Infection

• HIV Structure and Function:

  • Retrovirus with RNA as genetic material that targets CD4 receptors on T lymphocytes and other immune cells.

  • Viral transmission involves:

    1. Binding: HIV binds to CD4 receptors and co-receptors.

    2. Fusion: Viral core enters the host cell.

    3. Reverse Transcription: Viral RNA is converted to DNA.

    4. Integration: Viral DNA integrates into the host cell's DNA.

    5. Transcription and Translation: Production of new virions.

Associated Symptoms and Conditions

• Respiratory Symptoms:

  • Shortness of breath (SOB), cough, chest pain, pneumocystitis, and mycobacterium avium complex.

• Oncological Conditions:

  • Kaposi's sarcoma, HIV-associated lymphomas.

• Neurological Issues:

  • Cognitive issues, peripheral neuropathy, and HIV encephalopathy.

• Gastrointestinal Symptoms:

  • Oral candidiasis, severe diarrhea, and anorexia.

• Integumentary Symptoms:

  • Herpes and dermatitis.

• Ophthalmic Issues:

  • Retinitis due to cytomegalovirus (CMV).

Medications for HIV

• Non-NRTI Medications:

  • Enfuvirtide: Infected via injection; monitor for injection site reactions.

  • Maraviroc: Take without food; potential side effects include abdominal pain and dizziness.

• NRTIs and Other Classes:

  • Nevirapine: Avoid meals, watch for Stevens-Johnson syndrome.

  • Integrase Inhibitors (e.g., Raltegravir): Monitor for rash.

Allergic Disorders Overview

• Types of Allergic Disorders:

  • Type I: Anaphylactic reactions mediated by IgE.

  • Type II: Cytotoxic reactions involving IgG/IgM antibodies.

  • Type III: Immune complex-mediated disorders affecting joints and kidneys.

  • Type IV: Delayed hypersensitivity reactions.

Treatments for Allergies

• Medications:

  • Antihistamines: Reduce symptoms of allergic reactions.

    • Sedating (e.g., Benadryl) and Non-Sedating (e.g., Claritin) options.

  • Corticosteroids: Reduce inflammation in allergic reactions.

  • Allergy Immunotherapy: Gradual exposure to allergens to reduce sensitivity.

Managing Chronic Conditions

• Rheumatoid Arthritis (RA):

  • Autoimmune condition with treatment options including NSAIDs, DMARDs, and corticosteroids.

• Scleroderma and Fibromyalgia:

  • Involves managing chronic pain and dermatological symptoms.

• Diabetes Management:

  • Differentiation between Type I and II, emphasizing dietary control, exercise, and insulin management.

Gastrointestinal Issues Overview

• Pancreatitis:

  • Acute vs. chronic; symptoms include severe abdominal pain.

• Hepatic Disorders:

  • Encompasses hepatitis types A, B, and C leading to liver dysfunction.

• Cirrhosis:

  • Chronic condition with complications such as portal hypertension and ascites.

Eye and Ear Conditions

• Glaucoma:

  • Increased intraocular pressure, leading to optic nerve damage.

• Cataracts:

  • Opacity in the lens causing progressive loss of vision.

• Meniere's Disease:

  • Characterized by episodes of vertigo, tinnitus, and hearing loss.