Allergy and Immunology Flashcards
(29 cards)
Triggers the immune system to do something
Antigen (Ag)
Antigen that triggers the specific/exaggerated immune response
Allergen
IgE
Immunoglobin E
Normal Immune Response Steps
1-Antigen enters the body
2-Lympocytes recognized antigen as bad
3-Lympocytes produce antibody (IgE) specific to antigen
4-Antibody coats and binds to antigen, i.e. “tags” the antigen(creating Ab-Ag complex)
5-Free antibodies can circulate and attached to mast cells and basophiles
6-Other WBC eliminate the Ab-Ag complex
Specialized cells embedded in tissue. Recognize and respond to injury. Respond by inflammation. Local reaction
Mast cells
Special cells that are “on the go”, in the blood circulating
Basophils
Allergy immune response steps
1- Allergen recognized by “allergy” lymphocyte
2-Allergy antibody produced
3-Antibody coats and brings to allergen
4-Antibody from prior exposures remain bound to mast cells and basophils
5-Allergen attached to antibody bound cells
6-Cells (mast cells and basophils) degranulate
When mast cells and basophils degranulate due to the allergen attaching to the antibody what spills out?
Histamines, prostaglondins, leukothrenes
What are the chemicals that produce the signs and symptoms of the allergic reaction?
Histamines, prostaglondins, leukothrenes
Type one sensitivity reaction
Skin: Urticaria Eyes: Conjunctivitis Nasopharynx: rhinorrhea Pulmonary: Asthma, bronchitis, stridor GI: gastroenteritis
Onset (timing) of anaphalytic reaction
15-30 minutes from initial exposure
Delayed-15-30 minutes
Secondary reaction-definition and timing
Biphasic respone
Recur up to 4 hours after initial phase resolves
Nasal secretions
rhinorrhea
Histamine effects
Bronchoconstriction (due to increased mucus production) Peripheral vasodilation (increased permeability) Coronary vasoconstriction Intestinal smooth muscle contraction
Causes of peripheral vasodilation
1) Edema
2) Drop in blood pressure
Histamine-results
Wheezing, tightness
Swelling
Dysrhythmias
Abdominal cramps
Types of swelling
Facial edema, stridor, urticaria, itching, hypotension
Dysrhythmias associated with histamine results
Tachycardia
Atrial fibrillation
Fast onset of an increase in local vascular permeability in subcutaneous or submucosal tissue
Angioedema
Physiology of angioedema
Type 1 hypersensitivity reaction (IgE and mast cells mediated)
Heredity angioedema and ACE-I induced (bradykinin and Complement mediated reaction)
An allergic reaction is a Type ___ Hypersensitivity reaction
One
Types of hypersensitivity reactions
I: Allergy
II: Cytotoxic reaction (hemolysis due to blood type)
III: Immune complex disease
IV: Delayed type hypersensitivity reaction
V: Autoimmune reaction
Most common allergens
Food (4-5% children): Mike, egg, soy, wheat, peanut, tree nuts, fish, crustaceons
Insect bites
Medications: antibiotics, ACE-I
Reaction that does not require antibody production to mediate allergic reaction. Allergen stimulates the mast cell directly
Anaphylactoid reaction
