Immunity, Allergies, and Autoimmune Diseases

Immune System Functions

• Protect the body from invasion of organisms.
• Get rid of dead or damaged cells.
• Seek out mutated cells or cells that have problems.

Requirements for Optimal Function

• Intact skin to keep things out.
• Working innate immune system.
• Properly functioning immune system.
• Ability to recognize invaders and self.
• Immune system must retain the ability to recognize self, or immuno-driven problems, where the immune system loses the ability to recognize self, can occur.

Innate Immunity (What You're Born With)

• Barriers:
  • Skin
  • Blood-brain barrier
  • Cilia in the respiratory tract
  • Mucus
  • Tears to wash things out of the eyes
  • Stomach acid that kills swallowed bacteria

Acquired Immunity

• Develops over time.
• Active acquired immunity:
  • Body makes antibodies after infection or immunization.
• Passive acquired immunity:
  • Antibodies are obtained from another source.
  • Temporary (lasts a month or two).
  • Examples:
    • From mother to baby via placenta.
    • Breast milk.
    • Gamma globulins given after exposure to Hep C.

Suppressed Immune Response

• Primary immunodeficiency:
  • Born with a broken immune system.
  • Missing a component needed for proper function.
• Secondary immunodeficiency:
  • Born with a normal immune system, but something happens to cause it to become suppressed.
  • Examples:
    • Infection
    • Treatment like chemotherapy.

Exaggerated Immune Responses (Hypersensitivity Reactions): 4 Types

• Type I: Simple allergic reaction.
  • Example: Seasonal allergies like pollen.
• Type II: Tissue-specific autoimmune response.
  • Targets a specific tissue.
  • Examples:
    • Graves' disease (attacks thyroid).
    • Hemolytic anemia (attacks red blood cells).
• Type III: Immune complex-mediated reactions.
  • Systemic autoimmune problems.
  • Examples:
    • Lupus.
    • Rheumatoid arthritis.
• Type IV: Cell-mediated reactions.
  • Contact sensitivities.
  • Examples:
    • Poison ivy.
    • Metal allergies.

Local vs. Systemic Inflammation

• Localized inflammation:
  • Affects a specific area.
  • Example: bee sting leading to redness and swelling at the site.
  • Caused by:
    • Trauma.
    • Physical agents like sunburn.
    • Chemicals like bee venom.
    • Biological agents (pathogens).
  • Purpose: flush out foreign material, get rid of dead/damaged cells, and start tissue repair.
• Systemic inflammation:
  • Affects the entire body.
  • Symptoms look viral.
  • Symptoms:
    • Fever
    • Headache
    • Muscle aches
    • Chills
    • Weakness
    • Elevated white blood cell count (leukocytosis).

Hypersensitivities/Allergies

• Common allergens: dust, animal dander, venoms, drugs, smoke, feathers.
• Estimated 20-25% of the population suffers from allergies.
• Treatment:
  • Antihistamines (diphenhydramine/Benadryl)
    • Side effects: dry mouth, nausea, blurry vision, dizziness, drowsiness
    • Paradoxical responses (agitation and hyperactivity)
• Allergy testing:
  • Blood tests
  • Skin tests:
    • Grid is marked on the forearm or back, and small amounts of potential allergens are introduced.
    • A wheal (h e a l) and flare reaction indicates an allergy; the worse the reaction, the worse the allergy.
• Allergy shots:
  • Gradual exposure to small amounts of allergen to desensitize the immune system.
  • Avoid with allergens that cause anaphylaxis.

Important Note: Drug Allergies

• Never administer any drug to which the patient reports a previous allergic reaction; however, question further to assess the severity.
• In real-world scenarios, if a drug is the only choice, providers may administer it with steroids and Benadryl.

Patient Safety: Allergies

• Allergies should be noted everywhere:
  • Chart
  • Armband
  • Medication administration system (alerts).

Anaphylaxis

• Patients at risk should wear MedicAlert jewelry.
• Patients should carry epinephrine (EpiPen).
• EpiPen administration:
  • Remove caps from both ends.
  • Inject straight into the anterior thigh.
  • Can inject through clothes (unless very thick).
  • Hold for 15 seconds until clicking stops.

Anaphylaxis: Assessment

• Look for oral or tongue swelling indicating potential airway compromise.

Common Causes of Anaphylaxis

• Antibiotics (e.g., penicillin).
• Insect venoms (e.g., bees, scorpions).
• Contrast dye (for CT scans or X-rays).
• Anesthesia.
• Blood products.

Be Safe Guidelines during allergic reaction

• Seek immediate medical help.
• Identify the allergen.
• Follow-up with an allergy specialist.
• Carry epinephrine (EpiPen).

Pathophysiology of Anaphylaxis

• Flooding of histamine.
• Bronchospasm (difficulty breathing).
• Vasodilation (drop in blood pressure).
• Increased capillary permeability (fluid leaks out, leading to hypovolemic shock).

Treatment of Anaphylaxis

• Epinephrine (vasoconstrictor and bronchodilator).
• Antihistamines.
• Oxygen.
• Fluid resuscitation.
• Dopamine (to increase blood pressure).
• Nebulized albuterol (bronchodilator).
• Corticosteroids.

Autoimmune Diseases

• Involve the immune system attacking the body's own tissues.
• Can cause:
  • Destruction of body tissues (e.g., type 1 diabetes).
  • Abnormal organ growth (e.g., goiter in Graves' disease).
  • Changes in organ function (e.g., kidney damage in lupus).
• Body loses the ability to distinguish self from non-self.
• Etiology: genetic factors, environmental factors, and bacterial infections.

Anaphylaxis Symptoms

• Coughing and wheezing.
• Stridor.
• Vomiting, diarrhea.
• Weak, thready pulse.
• Neurological issues.
• Patient stating they are going to die.

Anaphylaxis treatment: E.A.G.L.E

• Every Allergy Ought to be Reported
• Epinephrine
• Antihistamines
• Glucagon
• Lungs (Oxygen)
• Every allergy ought to be reported

Autoimmune Diseases: General Information

• Body can no longer differentiate between self and non-self.
• Etiology: genetic predispositions, immune regulation problems, and environmental factors.
• Treatment Goals:
  • Decrease inflammation.
  • Suppress the immune system.

First-Line Treatments

• Corticosteroids (decrease inflammation, suppress the immune system; can increase glucose).
• NSAIDs (anti-inflammatory, pain relief, mild anti-clotting effects); stronger NSAIDs like fluoxetine or Lortol may be used.
• Immunosuppressive therapies.

General Considerations for Autoimmune Diseases

• Fatigue is common.
• Ensure adequate rest.
• Promote hydration and nutrition.
• Prevent infection (hand washing, avoiding crowds, masks).

Raynaud's Phenomenon

• Vasospasms in response to cold, leading to loss of perfusion in fingertips.
• Common in autoimmune diseases.

Video: Plaque Psoriasis

• Chronic inflammatory skin disease.
• Development of thick, red patches with silver scales.
• Autoimmune disorder causing overproduction of keratin.
• Periods of exacerbation and remission.
• May also have pitting or crumbling nails.
• Diagnosis: Typically through clinical examination, sometimes skin biopsy.
• Treatment:
  • Topical steroids.
  • Salicylic acid.
  • Coal tar (can stain skin, hair, and clothing).
  • Immunosuppressants and DMARDs (e.g., methotrexate).
  • UV light therapy (slows skin cell growth; requires eye protection).
  • Psoralen (increases skin sensitivity to UV light, enhancing therapy effects; increases skin cancer risk).
• Silvery scaling: Think psoriasis.

Video: Lupus (Systemic Lupus Erythematosus - SLE)

• Chronic inflammatory disorder of connective tissue.
• Causes widespread inflammation and tissue damage.
• Autoimmune disorder resulting in antinuclear antibodies (ANA).
• Inflammation and damage to skin, lungs, kidneys, and heart.
• Periods of exacerbation and remission.
• Risk Factors:
  • Women are much more likely to get lupus
  • Onset of the disease usually occurs between the ages of twenty and forty
  • Race also plays a role. African Americans, Asians, and Native Americans are at higher risk for getting lupus.
• Signs and Symptoms:
  • Fatigue
  • Joint pain
  • Fever
  • Butterfly rask across the face.
  • Raynaud's phenomenon
  • Anemia
  • Pericarditis.
  • Lymphadenopathy.
• Labs and Diagnosis:
  • Usually have a positive ANA titer, and they will also have decreased serum complement, so decreased C3 and C4.
  • In addition, they'll have decreased red blood cells, white blood cells, and platelet counts,
  • And then if their kidneys become involved at some point, then we would see an increase in BUN and creatinine as well.
• Treatment:
  • NSAIDs
  • Immunosuppressants: Prednisone, Methotrexate
  • Hydroxychloroquine is also an effective medication for lupus.
• Nursing care:
  • Monitor for complications, including renal failure
  • Provide teaching:
    • avoiding UV and the sun exposure to prevent skin damage.
    • The patient needs to really prevent infection, so they should avoid sick people and really protect themselves from getting infection.
    • patients need to take frequent rest periods as well because of that side effect of fatigue associated with systemic lupus.

Lupus (SLE) - Additional Information

• The immune system can attack almost any system in the body.
• Occurs typically in women of childbearing age.
• More common in Latino, Asian, and African Americans.
• When people with lupus die, it's typically from infections and diseases of the cardiovascular system, renal system, pulmonary system, and the central nervous system.
• There is cutaneous lupus that just attacks the skin.
• Patients often experience periods of remission and exacerbation.
• Most common symptoms: fatigue, anorexia, fever, nausea, weight loss.
• Musculoskeletal symptoms are also common.
• Photosensitivity: Disease and drugs make you sensitive to sunlight.

Diagnosing Lupus: SOAP BRAIN MD

• Serositis (pleuritis, pericarditis).
• Oral ulcers.
• Arthritis.
• Photosensitivity.
• Blood disorders (low counts of red blood cells, white blood cells, platelets).
• Renal involvement (proteinuria, elevated creatinine).
• ANA (antinuclear antibodies).
• Immunologic abnormalities.
• Neurological issues.
• Malar rash (Butterfly rash).
• Diagnosis is challenging.

Lupus: Management

• NSAIDs.
• Corticosteroids.
• Hydroxychloroquine.
• Immunosuppressive agents (CellCept, methotrexate).
• Monoclonal antibodies (if lupus nephritis).

Lupus: Patient Teaching

• Medication knowledge: drugs, doses, schedule, side effects.
• Sun protection: SPF 30 or higher, covering up.
• Activity: Stay as active as possible.
• Stress management.
• Pain management.
• Infection prevention: staying away from sick people.

Rheumatoid Arthritis (RA)

• Common autoimmune disease.
• Systemic inflammatory disease which impacts the joints, connective tissues and other organs such as eyes and lungs.
• Can be very painful but generally the disease can be manged with prescription medications.
• Affects more women than men.
• Peak onset: 30-60.

Rheumatoid Arthritis (RA): Stages, Causes, Effects

• Stage One: Affects lining of joints known as synovial membranes
• Stage Two: Body starts building granulation tissue that is visible on x-rays
• Stage Three: Deformities begin to appear and the process may cause nerve compression
• Stage Four: The joint is destroyed and may fuse (Ankylosis)
• Etiology: Not exactly konwn
• Effects: Causes damage to joints, eyes, skin, heart, lungs, liver, nervous system and blood vessels

Rheumatoid Arthritis (RA) vs Osteoarthritis (OA)

• With OA, its usually one side and caused to