title: The heterogeneity of allergic phenotypes: genetic and environmental interactions.
abstract: OBJECTIVE
  This article reinforces the reader's knowledge of the multifactorial nature of allergic diseases and of the heterogeneity of allergic phenotypes.
  
  
  METHODS
  Personal studies and an evidence-based approach is used to support the assumption that three major abnormalities concur in the pathophysiology of allergic diseases: 1) enhanced allergen recognition and specific immune response; 2) a T helper 2 cytokine profile that results in polyclonal immunoglobulin E activation and mast cell-eosinophilic inflammation; and 3) organ hyperreactivity.
  
  
  METHODS
  Examples of genetic and environmental factors that preferentially influence each of these distinct pathophysiologic abnormalities are provided.
  
  
  RESULTS
  Data presented indicate that allergic diseases distribute along a wide spectrum depending on the preferential pathophysiologic abnormalities operating in the individual patient.
  
  
  CONCLUSIONS
  Categorization of allergic patients into distinct clinical phenotypes might result in a more patient-oriented (rather than disease-oriented) approach, and hence, better management.
authors.affiliation: Institute of Neurobiology and Molecular Medicine, Italian National Research Council, Rome. se.bonini-CNR@flashnet.it
authors.forename: S
authors.initials: S
authors.lastname: Bonini
authors.forename: G
authors.initials: G
authors.lastname: Rasi
authors.forename: A
authors.initials: A
authors.lastname: Torre
authors.forename: M
authors.initials: M
authors.lastname: D'Amato
authors.forename: P M
authors.initials: PM
authors.lastname: Matricardi
mesh_terms: D000485:Allergens / Q000009:adverse effects; D004781:Environmental Exposure; D006801:Humans; D006967:Hypersensitivity / Q000145:classification* / Q000235:genetics / Q000503:physiopathology; D010641:Phenotype
chemical_list: D000485:Allergens