Ch 317 Allergies anaphylaxis Flashcards
leukotriene biosynthetic pathway
arachidonic acid is metabolized by 5-lipoxygenase (5-LO) in the presence of an integral nuclear membrane protein, the 5-LO activating protein (FLAP)
receptor has a preference for LTD4 and is blocked by the receptor antagonists in clinical use
CysLT1
contains genes implicated in the control of IgE levels
region of chromosome 5 (5q23-31)
Interleukin
control of IgE levels
IL-4
IL-13
Interleukin
mucosal mast cell hyperplasia
IL-3
IL-9
Interleukin
central to eosinophil development
IL-5 “EOSIN”
GM-CSF
T cell response IL-4
TH2 subset
T cell response interferon (IFN)
TH1
T cell response
IL-6 and TGF
TH17
(+) presence of specific IgE in patients with systemic anaphylaxis:
inject serum intradermally into a normal recipient, followed 24 h later by antigen challenge into the same site –> (+) wheal and flare
Prausnitz-Kaustner reaction
implicate mast cell activation in a systemic reaction
Elevations of tryptase levels
Dose epinephrine anaphylaxis
0.3 to 0.5 mL of 1:1000 (1 mg/mL) epinephrine SC or IM
MOA epinephrine
a- and B-adrenergic effects, (vasoconstriction, bronchial smooth-muscle relaxation, and attenuation of enhanced venular permeability)
involves only the superficial portion of the dermis, (well-circumscribed wheals with erythematous raised serpiginous borders and blanched centers that may coalesce to become giant wheals)
Urticaria
well-demarcated localized edema involving the deeper layers of the skin, including the subcutaneous tissue
Angioedema
Classification of Urticaria and/or Angioedema
Autoimmune
IgE-dependent
Classification of Urticaria and/or Angioedema
dermographism, cold, solar
IgE-dependent
Classification of Urticaria and/or Angioedema
Specific antigen sensitivity (pollens, foods, drugs, fungi, molds, Hymenoptera venom, helminths)
IgE-dependent
Classification of Urticaria and/or Angioedema
Hereditary angioedema: C1 inhibitor deficiency: null (type 1) and dysfunctional (type 2)
Acquired angioedema: C1 inhibitor deficiency: anti-idiotype and anti-C1 inhibitor
Angiotensin-converting enzyme inhibitors
Bradykinin-mediated
Classification of Urticaria and/or Angioedema
Necrotizing vasculitis
Complement-mediated
Classification of Urticaria and/or Angioedema
Serum sickness
Complement-mediated
Classification of Urticaria and/or Angioedema
Reactions to blood products
Complement-mediated
Classification of Urticaria and/or Angioedema
Direct mast cell-releasing agents (opiates, antibiotics, curare, D-tubocurarine, radiocontrast media)
Nonimmunologic
Classification of Urticaria and/or Angioedema
Agents that alter arachidonic acid metabolism (aspirin and NSAIDs, azo dyes, and benzoates)
Nonimmunologic
appearance of a linear wheal at the site of a brisk stroke with a firm object or by any configuration
Dermographism
chronic idiopathic urticaria, presents in response to a sustained stimulus such as a shoulder strap or belt, running (feet), or manual labor (hands)
Pressure urticaria