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ALLERGIES / Hypersensitivity disorders

Hypersensitivity refers to pathologic processes that result from immunologically specific interactions between antigens (exogenous or endogenous) and humoral antibodies or sensitized lymphocytes. This definition excludes those disorders in which demonstrated antibodies have no known pathophysiologic significance (eg, the antibody to heart tissue that follows heart surgery or MI), even though their presence may have diagnostic value.

The Merck Manual of Diagnosis and Therapy
Section 12, Chapter 148
http://www.merck.com/pubs/mmanual/section12/chapter148/148a.htm
date accessed: 2002/02/28