title: Testing for cattle allergy: modified diagnostic cutoff levels improve sensitivity in symptomatic claw trimmers.
abstract: BACKGROUND
  The diagnosis of cattle-related sensitization is complicated by the variability and complexity of cattle allergen extracts.
  
  
  OBJECTIVE
  To evaluate a modified diagnostic procedure leading to more accurate results especially in the early phase of sensitization.
  
  
  METHODS
  We tested 27 claw trimmers with and 65 without cattle-related symptoms using two commercially available cattle allergen extracts. We also used a self-prepared cattle allergen mix designed to represent the full spectrum of cattle allergens from a typical agricultural workplace.
  
  
  RESULTS
  More than 50% of symptomatic claw trimmers showed negative test results with commercial extracts and a sensitization cutoff point of 0.35 kU/l. In contrast, with the self-prepared cattle allergen mix, positive results were observed for almost all of them. Evaluating the results of the commercial test kits at different cutoff levels, we found an ideal cutoff point to improve the sensitivity at 0.2 kU/l.
  
  
  CONCLUSIONS
  Additional tests with self-made cattle hair extracts can help to bridge the diagnostic gap seen in patients showing cattle-related symptoms, but negative results in commercially available tests. For early-stage sensitization screening, we propose to lower the cutoff level indicating sensitization to 0.2 kU/l.
authors.affiliation: Institute for Occupational and Social Medicine, University of Göttingen, Waldweg 37, 37037 Göttingen, Germany. aheutel@gwdg.de
authors.forename: Astrid
authors.initials: A
authors.lastname: Heutelbeck
authors.forename: Natalja
authors.initials: N
authors.lastname: Dik
authors.forename: Ernst
authors.initials: E
authors.lastname: Hallier
authors.forename: Torsten
authors.initials: T
authors.lastname: Zuberbier
authors.forename: Karl-Christian
authors.initials: KC
authors.lastname: Bergmann
mesh_terms: D000328:Adult; D000485:Allergens / Q000276:immunology / Q000302:isolation & purification*; D000818:Animals; D002417:Cattle; D003955:Diagnostic Tests, Routine / Q000379:methods*; D005260:Female; D005858:Germany; D006801:Humans; D006967:Hypersensitivity / Q000175:diagnosis* / Q000276:immunology; D015151:Immunoblotting; D007073:Immunoglobulin E / Q000097:blood / Q000276:immunology; D008297:Male; D008875:Middle Aged; D016273:Occupational Exposure; D012680:Sensitivity and Specificity; D055815:Young Adult
chemical_list: D000485:Allergens; D007073:Immunoglobulin E