title: Relationship of skin-prick reactivity to aeroallergens and hyperresponsiveness to challenges with methacholine and adenosine monophosphate.
abstract: BACKGROUND
  Clarification of the relationship between atopy and bronchial hyperresponsiveness (BHR), both key features of asthma, is critical to our understanding of the disease. We therefore investigated the putative relationship between skin-prick reactivity to aeroallergens and BHR to direct and indirect stimuli.
  
  
  METHODS
  We performed a retrospective analysis of data from 332 patients presenting with a diagnosis of asthma. Patients were characterized by skin prick tests (SPT), spirometry and bronchial challenge with methacholine and adenosine monophosphate (AMP).
  
  
  RESULTS
  For patients who had BHR to methacholine but not AMP, the presence of atopy was associated with a lower PD20 (the provocative dose of methacholine producing a fall in FEV1 of 20%), amounting to a geometric mean (95% confidence interval (CI)) of 2.3-fold (1.4-4.0) difference. Furthermore, the number of skin-prick positive (SPP) responses was related to methacholine reactivity: 0-1 SPP, PD20 = 69.9 micro g; 2-4 SPP, PD20 = 47.8 micro g; 5-8 SPP, PD20 = 35.6 micro g. There was a 2.0- fold (1.1-3.6) difference between the groups with a low (0-1 SPP) and high (5-8 SPP) degree of skin-prick reactivity. A similar pattern was seen when data were analyzed including only perennial allergens. Spirometry was unrelated to the degree of skin-prick reactivity.
  
  
  CONCLUSIONS
  These results suggest that skin-prick reactivity to aeroallergens is associated with BHR to methacholine.
authors.affiliation: Asthma and Allergy Research Group, Ninewells Hospital and Medical School, University of Dundee, Scotland.
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Fowler
authors.forename: Brian J
authors.initials: BJ
authors.lastname: Lipworth
mesh_terms: D000249:Adenosine Monophosphate / Q000009:adverse effects*; D000328:Adult; D000368:Aged; D000397:Air Pollution; D000485:Allergens / Q000009:adverse effects* / Q000276:immunology; D016535:Bronchial Hyperreactivity / Q000209:etiology* / Q000276:immunology; D001985:Bronchial Provocation Tests; D016085:Bronchoconstrictor Agents / Q000009:adverse effects*; D003429:Cross Reactions / Q000187:drug effects / Q000276:immunology; D005260:Female; D005540:Forced Expiratory Flow Rates / Q000276:immunology; D005541:Forced Expiratory Volume / Q000276:immunology; D006801:Humans; D006969:Hypersensitivity, Immediate / Q000209:etiology* / Q000276:immunology; D008297:Male; D016210:Methacholine Chloride / Q000009:adverse effects*; D008875:Middle Aged; D011058:Pollen / Q000276:immunology; D012189:Retrospective Studies; D012882:Skin Tests; D013147:Spirometry
chemical_list: D000485:Allergens; D016085:Bronchoconstrictor Agents; D016210:Methacholine Chloride; D000249:Adenosine Monophosphate