RT Book, Section
A1 Yazdany, Jinoos
A1 Manno, Rebecca
A1 Hellmann, David B.
A1 Imboden Jr., John B.
A2 Papadakis, Maxine A.
A2 McPhee, Stephen J.
A2 Rabow, Michael W.
SR Print(0)
ID 1175804308
T1 Immediate Hypersensitivity
T2 Current Medical Diagnosis & Treatment 2021
YR 2021
FD 2021
PB McGraw-Hill Education
PP New York, NY
SN 9781260469868
LK accessmedicine.mhmedical.com/content.aspx?aid=1175804308
RD 2023/02/05
AB IgE  antibodies  occupy  receptor  sites  on  mast  cells.  Within  minutes  after  exposure  to  the  allergen,  a  multivalent  antigen  links  adjacent  IgE  molecules,  activating  and  degranulating  mast  cells.  Clinical  manifestations  can  be  explained  by  the  effects  of  released  mediators  on  target  end  organs.  Both  preformed  and  newly  generated  mediators  cause  vasodilation  and  permeability  changes,  visceral  smooth  muscle  contraction,  mucous  secretory  gland  stimulation,  vascular  permeability,  and  tissue  inflammation.  Arachidonic  acid  metabolites,  cytokines,  and  other  mediators  (such  as  chemoattractants)  induce  a  late-phase  inflammatory  response  that  appears  several  hours  later  in  affected  tissues  when  antigen  exposure  is  continuous  (eg,  pollen)  or  chronic.