1. Anaphylaxis
DR. HIWA OMER AHMED
PROFESSOR IN GENERAL AND BARIATRIC SURGERY
UNIVERSITY OF SULAIMANI
COLLEGE OF MEDICINE – SULAIMANI CITY- KURDISTAN
1
2. Anaphylaxis
The term comes from the Ancient Greek: ἀνά, romanized: ana, lit. 'against', and the
Ancient Greek: φύλαξις, romanized: phylaxis, lit. 'protection
Anaphylaxis is a serious allergic reaction that is rapid in onset and may cause death
Worldwide, 0.05–2% of the population is estimated to experience anaphylaxis at some point in
life.
It occurs most often in young people and females
The people who go to a hospital with anaphylaxis in the United States about 0.3% die.
1/23/2023
3:22 PM
2
3. Hypersensitivity
Allergic reactions
4 types
Allergy = Alle + rgy
Allos + Ergon
Others + Reaction, has genetic predisposition
Antigen, Allergin
Usually Molecules from out side + 2 steps Sensitization(1st) !!! anaphylactoid Rn.
breathe, intake, contact subsequent exposure (^ serious)
1/23/2023
3:22 PM
3
4. Types
Type 1 IG-Einvolved , Immediate ( Minutes ): Most allergic reaction are Ig-E mediated
IG_ M,G: cytotoxic, as they involve antibodies that are specific to particular tissues
within the body and cause destruction of cells in these tissues (e.g., autoimmune
hemolytic anemia, Goodpasture syndrome).
Type 3 IG G: are immune complex-mediated, with tissue damage caused by antigen-
antibody complex deposition (e.g., many vasculitides and glomerulonephritis).
Type 4 :Cell mediated: reactions like transplant rejection + (e.g., TB skin tests, contact
dermatitis) are delayed and cell-mediated and are the only hypersensitivity reaction
that involves sensitized T lymphocytes rather than antibodies. `
1/23/2023
3:22 PM
4
17. Cross-reactivity
Individuals with allergies may also react to substances that contain particles that
are similar to the main antigen.
Examples (primary allergen – cross-reactant allergen) [9][10]
Pollen – various foods (e.g., apple, hazelnut, carrot, kiwi, apricots, peaches)
Mites نه
هگ
:
- – crustaceans (krəˈstāSHə) )
کان
هتوێکڵدار
:
Latex – exotic fruits (e.g., banana, avocado, kiwi)
Bird dander (ˈdandər) ڕ
هپ
: – egg yolk
Cat dander (ˈdandər) موو
: – pork
1/23/2023
3:22 PM
17
18. Treatment
1/23/2023
3:22 PM
18
Urticaria : avoid offending agent (if known), H1-receptor locker (e.g., cetirizine), glucocorticoids
Drug reactions
Mild reactions (mild Urticaria/angioedema) may be treated by removing the offending drug and monitoring
± antihistamines.
Moderate reactions (more pronounced urticaria/angioedema) should be treated with withdrawal of the
offending drug and antihistamines ± glucocorticoids.
Severe reactions require emergency resuscitation (see anaphylaxis).
Emergency (self-) medication: Patients with known allergic reactions to food or insect venom, for
example, may be provided with antihistamines, corticosteroids, and epinephrine auto-injectors for self-
treatment (in patients at risk of anaphylaxis).
19. Allergen immunotherapy (desensitization)
Indication
Documented IgE-mediated allergy (e.g., allergic rhinitis, allergic asthma, allergy to wasp or bee venom)
Significant symptoms and inadequate relief from symptomatic therapy and exposure prophylaxis
Significant symptoms despite symptomatic therapy and avoidance of the allergen
Method
Only available for some allergens but can be quite effective
Application of specific antigen in subclinical dose (subcutaneous, mucosal)
Slow escalation of dose
Goal: increased production of IgG antibodies instead of excessive IgE production (isotype switching)
Duration of treatment: at least 3 years
1/23/2023
3:22 PM
19
20. Treatment of anaphylaxis
Withdrawal of offending agent if possible (e.g., in drug reactions)
Airway: examination of airway and intubation if obstruction seems imminent
Epinephrine IM
Antihistamines
H1 antihistamine (e.g., diphenhydramine) IV for urticaria
H2 antihistamine (e.g., ranitidine) IV
Methylprednisolone
Positioning: The patient should be placed in a recumbent/supine position with elevation of the lower
extremities.
O2 by facemask
If the patient is hypotensive: volume replacement – normal saline 1–2 L IV rapid bolus
Bronchospasm and no benefit of epinephrine: nebulized albuterol (salbutamol)
Continuous monitoring of blood pressure, heart rate, heart function, and pulse oximetry; urine output should
also be monitored in hypotensive patients receiving resuscitation. 1/23/2023
3:22 PM
20
