RT Book, Section
A1 Levinson, Warren
A1 Chin-Hong, Peter
A1 Joyce, Elizabeth A.
A1 Nussbaum, Jesse
A1 Schwartz, Brian
SR Print(0)
ID 1175827237
T1 Hypersensitivity (Allergy)
T2 Review of Medical Microbiology & Immunology: A Guide to Clinical Infectious Diseases, 16e
YR 2020
FD 2020
PB McGraw Hill
PP New York, NY
SN 9781260116717
LK accessmedicine.mhmedical.com/content.aspx?aid=1175827237
RD 2024/04/19
AB Hypersensitivity  reactions  are  exaggerated  or  inappropriate  immune  responses  to  benign  antigens.  It  is  the  immune  response,  not  the  antigens,  which  are  harmful  to  the  host.  Usually,  hypersensitivity  reactions  occur  in  response  to  external  stimuli  (antigens),  whereas  autoimmune  reactions  (see  Chapter  66)  occur  in  response  to  internal  stimuli  (antigens).  The  term  allergy  is  often  equated  with  hypersensitivity  but  more  accurately  should  be  limited  to  the  immunoglobulin  (Ig)  E-mediated  reactions  discussed  later  in  the  section  “Type  I:  Immediate  (Anaphylactic)  Hypersensitivity.”  Note  that  many  autoimmune  diseases  have  pathologic  features  of  one  or  more  hypersensitivity  reactions.  This  chapter  will  cover  the  patterns  of  hypersensitivity  reactions  using  examples  of  diseases  in  which  there  are  known  external  triggers.  Chapter  66  will  cover  autoimmune  diseases,  in  which  the  immune  reactions  are  largely  against  are  self-antigen(s).