The Immune System and Immunity Types

• The immune system protects the body from foreign invaders, such as bacteria, viruses, fungi, and toxins.
• It also recognized and destroys abnormal cells, such as cancer cells.
• Immunodeficiency is when the immune system is incompetent or unable to respond effectively
• Hypersensitivity is when the immune system overreacts to a foreign substance.

Organs of the Immune System

• Bone marrow produces B cells and pre-T cells.
• The thymus gland matures T cells and is most active during puberty.
• Lymph nodes filter pathogens and cancer cells from lymph.
• The spleen filters pathogens and damaged red blood cells from the blood.
• The liver filters bacteria from the blood.

Types of Immunity

• Natural immunity is present at birth and provides immediate, short-term protection against foreign antigens.
• Acquired immunity develops after exposure to a foreign antigen and provides long-term protection.
• Active immunity is when the body produces its own antibodies in response to an antigen.
• Passive immunity is when the body receives antibodies from an external source.
• Humoral immunity involves B cells, which produce antibodies that target specific antigens in body fluids.
• Cell-mediated immunity involves T cells, which directly attack antigens or release cytokines that activate other immune cells.

Lines of Defence

• The first line of defense includes physical and chemical barriers that prevent pathogens from entering the body, such as the skin, mucous membranes, and stomach acid.
• The second line of defense includes phagocytes, natural killer cells, and inflammation, which attack pathogens that have entered the body.
• The third line of defense is the immune response, which involves B cells and T cells that target specific antigens.

The Inflammatory Response

• Inflammation is a localized response to tissue injury or infection which neutralizes and destroys harmful agents, limits the spread of infection, and prepares damaged tissue for repair.
• The signs and symptoms of inflammation include redness, heat, swelling, pain, and loss of function.

The Antigen-Antibody Response

• An antigen is a substance that triggers an immune response.
• An antibody is a protein produced by B cells that binds to a specific antigen and neutralizes it.
• When an antibody binds to an antigen, it forms an antigen-antibody complex, which can be eliminated by phagocytes or the complement system.

The Complement System

• The complement system is a group of proteins in the blood that enhance the ability of antibodies and phagocytes to clear pathogens from the body.

Lifespan Considerations

• Infants have immature immune systems and are more susceptible to infections. The newborns receive passive immunity from their mothers.
• Older adults have weakened immune systems and are more susceptible to infections, cancer, and autoimmune diseases.

Data Collection

• The nurse should assess the patient's history of infections, allergies, immunizations, and medications.
• A physical exam should be performed to assess for signs and symptoms of infection, inflammation, or immune dysfunction.

Diagnostic Tests

• A complete blood count (CBC) can assess the number and type of white blood cells, which can indicate infection or immune dysfunction.
• An enzyme-linked immunosorbent assay (ELISA) can detect the presence of antibodies to specific antigens.
• A Western blot test can confirm the results of an ELISA test.
• A T-cell and B-cell count can assess the number and function of these immune cells.
• Allergy testing can identify specific allergens that trigger an immune response.

Nursing Diagnoses

• Risk for infection
• Impaired skin integrity
• Imbalanced nutrition: less than body requirements
• Fatigue
• Social isolation

Planning

• The nurse should develop a plan of care that addresses the patient's specific needs and goals.
• The plan should include interventions to prevent infection, promote healing, manage symptoms, and provide emotional support.

Implementation

• Interventions to prevent infection include hand hygiene, proper nutrition, adequate rest, and avoiding exposure to pathogens.
• Interventions to promote healing include wound care, pain management, and nutritional support.
• Interventions to manage symptoms include medication administration, comfort measures, and patient education.
• Interventions to provide emotional support include active listening, encouragement, and referrals to support groups or counseling.

Evaluation

• The nurse should evaluate the effectiveness of the plan of care and make adjustments as needed.
• The patient's progress toward achieving the goals should be documented.

Therapeutic Measures

• Medications commonly used to treat immune disorders include antibiotics, antivirals, antifungals, corticosteroids, and immunosuppressants.
• Other therapeutic measures include bone marrow transplantation, stem cell transplantation, and gene therapy.

Common Medical Treatments

• Antibiotics are used to treat bacterial infections.
• Antivirals are used to treat viral infections.
• Antifungals are used to treat fungal infections.
• Corticosteroids are used to reduce inflammation.
• Immunosuppressants are used to suppress the immune system.
• Bone marrow transplantation is used to replace damaged or diseased bone marrow with healthy bone marrow.
• Stem cell transplantation is used to replace damaged or diseased cells with healthy cells.
• Gene therapy is used to correct genetic defects that cause immune disorders.