Type I Hypersensitivity: Anaphylaxis by https://padlet.com/amoon3964_/iiktnoild2qwavk3 en-us 2023-10-13 14:18:21 UTC 2023-10-18 18:54:41 UTC hello@padlet.com Cellular Pathophysiology of Type I Hypersensitivity: Anaphylaxis amoon3964_ https://padlet.com/amoon3964_/iiktnoild2qwavk3/wish/2745589246
  • Begins with sensitization: an individual's initial exposure to an allergen.
    • Form immunologic memory of allergen
  • An anaphylactic response occurs during re-exposure to the same allergen. 
  • Immune response: IgE antibodies bind to mast cells and basophils.
    • Mast cell: inflammatory cascade; degranulation  
  • IgE antibodies signal the mast cells to degranulate and release mediators.
    • Histamine 




    • Sources:
    Abbas, M., Akel, H., & Moussa, M. (2023, January). Type I hypersensitivity reaction - statpearls - NCBI bookshelf. National Library of Medicine. https://www.ncbi.nlm.nih.gov/books/NBK560561/ 

    Rogers, J. (2019). McCance & Huether's Pathophysiology (9th ed.). Elsevier Health Sciences (US). https://pageburstls.elsevier.com/books/9780323789905
    ]]>     2023-10-13 18:31:01 UTC https://padlet.com/amoon3964_/iiktnoild2qwavk3/wish/2745589246     Tissue/Organ Level Pathophysiology of Type I Hypersensitivity: Anaphylaxis amoon3964_ https://padlet.com/amoon3964_/iiktnoild2qwavk3/wish/2745593696
  • ​​Histamine released from mast cells binds to H1 receptors on various target cells.
    • GI tract
    • Skin
    • Respiratory tract 
  • Mast cells are sensitive to the effects of histamine released from them
    • Inflammatory response 
  • Vascular Effects: histamine causes vasodilation and increased vascular permeability. 
  • Respiratory Effects: histamine causes bronchoconstriction
  • Skin Effects: histamine causes itching and hives (urticaria) in the skin.
  • Gastrointestinal Effects: histamine can increase the permeability of blood vessels, leading to localized swelling and inflammation. 
    • stimulate nerve endings causing abdominal cramps and discomfort. 
    • affect smooth muscle of the GI tract 
  • Systemic: affecting multiple tissues and organs; septic shock 



    • Sources:
    Abbas, M., Akel, H., & Moussa, M. (2023, January). Type I hypersensitivity reaction - statpearls - NCBI bookshelf. National Library of Medicine. https://www.ncbi.nlm.nih.gov/books/NBK560561/ 

    Rogers, J. (2019). McCance & Huether's Pathophysiology (9th ed.). Elsevier Health Sciences (US). https://pageburstls.elsevier.com/books/9780323789905
    ]]>     2023-10-13 18:36:10 UTC https://padlet.com/amoon3964_/iiktnoild2qwavk3/wish/2745593696     Clinical Manifestations: Anaphylaxis nyuparhizgari https://padlet.com/amoon3964_/iiktnoild2qwavk3/wish/2746200919
  • Skin:
    • Manifestation: pruritus (itchy skin), tingling, warmth, hives

    Rationale: Histamine and chemical mediators irritate sensory nerves
     
    • Respiratory:
     Manifestation: Difficulty with breathing, cough, wheezing, chest pain/tightness

    Rationale: Chemical mediators cause contraction of smooth muscles in bronchioles, edema, and increased secretions, leading to narrowing of the airways & lack of oxygen
     
    • Cardiovascular:
    Manifestation: Decreased blood pressure, weak pulse

    Rationale: Chemical mediators cause general vasodilation, with rapid, weak pulse, perhaps irregular, leading to low blood pressure; sympathetic nervous system responds by increasing rate
     
    • Central Nervous System:
     Manifestation: Anxiety and fear (early); weakness, dizziness, and loss of consciousness

    Rationale: Early, sympathetic response; later, lack of oxygen to the brain because of low blood pressure and respiratory obstruction

    • Gastrointestinal:
    Manifestation: Nausea, Vomiting

    Rationale: Histamines released to fight off allergies can cause inflammation and irritation in the stomach tissues, leading to uneasiness and nausea

    Sources:
    Anaphylaxis. Allergy & Asthma Network. (2023, June 27). https://allergyasthmanetwork.org/anaphylaxis/ 

    Poziomkowska-Gęsicka I, Kurek M. Clinical Manifestations and Causes of Anaphylaxis. Analysis of 382 Cases from the Anaphylaxis Registry in West Pomerania Province in Poland. Int J Environ Res Public Health. 2020 Apr 17;17(8):2787. doi: 10.3390/ijerph17082787. PMID: 32316622; PMCID: PMC7215547.
    ]]>     2023-10-14 16:08:04 UTC https://padlet.com/amoon3964_/iiktnoild2qwavk3/wish/2746200919     Overview aades6874_ https://padlet.com/amoon3964_/iiktnoild2qwavk3/wish/2746227246
  • Anaphylaxis is a potentially serious life-threatening allergic reaction to a usually harmless substance that the body mistakes to be harmful (allergen)
  • Immediate immune and inflammatory response that occurs within seconds or minutes
  • When an allergen is introduced to the body, the immune system releases a large amount of histamine which results in sudden drop in blood pressure, difficulty breathing due to narrowed airways, skin rash and other possible symtpoms

    • Rogers, J. (2019). McCance & Huether’s Pathophysiology (9th ed.). Elsevier Health Sciences (US). https://pageburstls.elsevier.com/books/9780323789905

    Mayo Clinic. (2021). Anaphylaxis. 
    https://www.mayoclinic.org/diseases-conditions/anaphylaxis/symptoms-causes/syc-20351468
    ]]>     2023-10-14 16:46:04 UTC https://padlet.com/amoon3964_/iiktnoild2qwavk3/wish/2746227246     Treatment aades6874_ https://padlet.com/amoon3964_/iiktnoild2qwavk3/wish/2746229104 Treatment:
    • Immediate and necessary-Epinephrine (adrenaline) acts as a vasoconstrictor (narrows blood vessels)
      • Intravenous
      • Intramuscular
    • Adjunct therepay:
      • Bronchiodilators (relaxes airway), 
      • H1 and H2 receptor blockers, 
      • IV corticosteroids
    • IV fluids, O2 supplementation
    • Critical care
      • Intubation

    Osmosis from Elsevier. (2023). Notes: Type 1 hypersensitivity reactions. https://www.osmosis.org/notes/Type_I_hypersensitivity_reactions
    ]]>     2023-10-14 16:48:02 UTC https://padlet.com/amoon3964_/iiktnoild2qwavk3/wish/2746229104     Common Allergens aades6874_ https://padlet.com/amoon3964_/iiktnoild2qwavk3/wish/2746297028
  • Most common allergens are caused by environmental allergens such as pollen, insect stings, nuts, medications.
    • ]]>     2023-10-14 18:40:19 UTC https://padlet.com/amoon3964_/iiktnoild2qwavk3/wish/2746297028     Hypersensitivity Steps aades6874_ https://padlet.com/amoon3964_/iiktnoild2qwavk3/wish/2746332687 Creative Med Dose. (2023). Type I hypersensitivity: immediate. https://creativemeddoses.com/topics-list/type-1-hypersensitivity-immediate/ ]]> 2023-10-14 19:51:51 UTC https://padlet.com/amoon3964_/iiktnoild2qwavk3/wish/2746332687 Anaphylaxis as Type I Hypersensitivity nyuparhizgari https://padlet.com/amoon3964_/iiktnoild2qwavk3/wish/2746351647
  • Type I hypersensitivity is characterized by the immunoglobulin E (IgE)–mediated release of histamine and other mediators from mast cells and basophils.
  • This reaction is always rapid, occurring within minutes of exposure to an antigen. Anaphylaxis symptoms usually occur within minutes of exposure to an allergen. 
  • Anaphylaxis conforms to this traditional definition as it is "involves the release of numerous chemical mediators from the degranulation of basophils and mast cells after re-exposure to a specific antigen(Mclendon & Sternard, 2023)."
  • Thus, anaphylaxis is complication of type 1 hypersensitivity in its most extreme form.

    •  Sources:
    McLendon K, Sternard BT. Anaphylaxis. [Updated 2023 Jan 26]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK482124/
    ]]>     2023-10-14 20:34:45 UTC https://padlet.com/amoon3964_/iiktnoild2qwavk3/wish/2746351647     How to Administer Epinephrine: nyuparhizgari https://padlet.com/amoon3964_/iiktnoild2qwavk3/wish/2746358920
  • To self-administer epinephrine, remove the autoinjector from its carrying tube
  • Next, grasp the unit with the black tip (injecting end) pointed downward. Form a fist around the device, and remove the gray safety release cap. 
  • Hold the black tip near the outer thigh and swing and jab firmly into the outer thigh at a 90-degree angle until a click is heard. 
  • Hold the device firmly in place for about 10 seconds, remove the device, and massage the site for about 10 seconds.
    • Source:
    How to use EpiPen®. How to Use EpiPen® | Epipen.ca. (n.d.). https://www.epipen.ca/how-to-use-epipen 
    ]]>     2023-10-14 20:52:18 UTC https://padlet.com/amoon3964_/iiktnoild2qwavk3/wish/2746358920     Risk Factors aades6874_ https://padlet.com/amoon3964_/iiktnoild2qwavk3/wish/2746818151 Risk factors for anaphylaxis include:
    • previous anaphylactic reaction-future reactions can be more severe than the first reaction
    • allergies
    • asthma
    • family history of anaphylaxis
    • Other health conditions: heart disease or mastocytosis (irregular accumulation of a certain type of white blood cells-mast cells)

    Gotter, A. (2019). Anaphylactic shock: what you need to know. Healthline. https://www.healthline.com/health/anaphylactic-shock

    Mayo Clinic. (2021). Anaphylaxis. 
    https://www.mayoclinic.org/diseases-conditions/anaphylaxis/symptoms-causes/syc-20351468
    ]]>     2023-10-15 15:06:23 UTC https://padlet.com/amoon3964_/iiktnoild2qwavk3/wish/2746818151