title: Relationship between total and allergen-specific IgE serum levels and presence of symptoms in farm workers sensitized to Tetranychus urticae.
abstract: BACKGROUND
  Clinical complaints in atopic subjects with asthma and rhinitis occur more frequently in the presence of high total and allergen-specific IgE serum levels. Here we report on the relationship between total and allergen-specific IgE serum levels and presence of symptoms in an unselected farmer population sensitized to Tetranychus urticae (TU).
  
  
  METHODS
  Farmers were recruited as previously described. Total IgE and allergen-specific IgE were measured by immunoassay in TU-positive skin prick test (SPT) farmers (n = 58) and two control groups including Dermatophagoides pteronyssinus (Dp)-positive SPT subjects (n = 40) and non-atopic, TU-negative SPT healthy farmers (n = 25).
  
  
  RESULTS
  Both TU+ and Dp+ subjects had significantly higher total IgE values (P < 0.001) than healthy non-atopic subjects. TU-specific IgE levels were significantly more elevated in symptomatic than non-symptomatic TU+ subjects (P = 0.028). Dp-specific IgE levels were higher in symptomatic than non-symptomatic Dp+ subjects (P = 0.003). Finally, total IgE levels were significantly higher in the symptomatic than non-symptomatic subgroups in both TU+ and Dp+ subjects (P < 0.0001 and P = 0.007, respectively). Logistic regression analysis showed that only total IgE concentrations were significant predictors of current symptoms in TU+ subjects.
  
  
  CONCLUSIONS
  High total IgE and allergen-specific IgE levels are associated with symptoms in TU+ subjects. Definition of their predictive value requires further studies.
mesh_terms: D000328:Adult; D000382:Agricultural Workers' Diseases / Q000097:blood / Q000276:immunology* / Q000628:therapy*; D000485:Allergens / Q000097:blood* / Q000276:immunology*; D003429:Cross Reactions / Q000276:immunology; D000939:Epitopes / Q000276:immunology*; D005260:Female; D006801:Humans; D006969:Hypersensitivity, Immediate / Q000097:blood / Q000276:immunology* / Q000628:therapy*; D007114:Immunization; D007073:Immunoglobulin E / Q000097:blood* / Q000276:immunology*; D008297:Male; D011237:Predictive Value of Tests; D015995:Prevalence; D016032:Randomized Controlled Trials as Topic; D016037:Single-Blind Method; D012882:Skin Tests; D013223:Statistics as Topic; D040102:Tetranychidae / Q000276:immunology*
chemical_list: D000485:Allergens; D000939:Epitopes; D007073:Immunoglobulin E