title: Allergic asthma after flour inhalation in subjects without occupational exposure to flours: an experimental pilot study.
abstract: OBJECTIVE
  Cross-reactivity between grass pollen and grain flour allergens is well known, but their significance in apprentice bakers with primary sensitization to grass pollen is not known.
  
  
  METHODS
  Twenty-five subjects with mild asthma (most of them with hay fever), but without prior occupational flour exposure, underwent standardized experimental inhalation challenges with placebo and wheat and rye flours in randomized order on three consecutive days. Sensitization to flours and environmental allergens was assessed by skin prick tests and specific IgE antibodies in sera. IgE inhibition experiments were performed with wheat and rye flours as solid phases, and grass and tree pollen as inhibitors.
  
  
  RESULTS
  Five subjects experienced a positive reaction after flour inhalation (responders), whereas 20 subjects did not show such a reaction (non-responders). All responders showed sensitizations to flours, whereas only 25% of the non-responders demonstrated the same sensitization. Specific IgE concentrations to flours, but also to grass and tree pollen, were higher in responders. Inhibition experiments demonstrated cross-reactivity between flours and grass or tree pollen, with higher inhibition rates in responders.
  
  
  CONCLUSIONS
  Subjects with pronounced sensitizations to grass or tree pollen, but without prior occupational exposure to flours, may experience both sensitization and allergic asthmatic reactions to flours due to cross-reactive grass and tree pollen allergens.
authors.affiliation: Institute for Prevention and Occupational Medicine of the German Social Accident Insurance, Institute of the Ruhr University (IPA), Bürkle-de-la-Camp-Platz 1, Bochum, Germany. rget@ipa-dguv.de
authors.forename: R
authors.initials: R
authors.lastname: Merget
authors.forename: I
authors.initials: I
authors.lastname: Sander
authors.forename: V
authors.initials: V
authors.lastname: van Kampen
authors.forename: U
authors.initials: U
authors.lastname: Beckmann
authors.forename: E
authors.initials: E
authors.lastname: Heinze
authors.forename: M
authors.initials: M
authors.lastname: Raulf-Heimsoth
authors.forename: T
authors.initials: T
authors.lastname: Bruening
mesh_terms: D000328:Adult; D000485:Allergens / Q000009:adverse effects* / Q000276:immunology; D001249:Asthma / Q000209:etiology* / Q000276:immunology; D003429:Cross Reactions / Q000276:immunology; D005260:Female; D005433:Flour / Q000009:adverse effects*; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood / Q000276:immunology; D019570:Inhalation Exposure / Q000009:adverse effects; D008297:Male; D008403:Mass Screening; D008875:Middle Aged; D016273:Occupational Exposure / Q000009:adverse effects*; D010865:Pilot Projects; D006255:Rhinitis, Allergic, Seasonal / Q000276:immunology; D012882:Skin Tests; D011795:Surveys and Questionnaires; D021182:Wheat Hypersensitivity / Q000276:immunology; D055815:Young Adult
chemical_list: D000485:Allergens; D007073:Immunoglobulin E