title: Monosensitization and polysensitization in allergic rhinitis.
abstract: BACKGROUND
  Polysensitization is common in patients with allergic rhinitis (AR) and may affect clinical feature. However, there are patients who remain monosensitized.
  
  
  OBJECTIVE
  This cross-sectional study aimed at evaluating a large cohort of AR patients to define the percentage and the features of mono- and poly-sensitized subjects.
  
  
  METHODS
  This observational cross-sectional study included a large group of AR patients: 2415 subjects (1958 males, mean age 24.6 ± 5 years) were consecutively evaluated. Symptom severity, type and number of sensitizations, and AR duration were considered.
  
  
  RESULTS
  621 patients (25.7%) were monosensitized: 377 to Parietaria, 194 to house dust mites, 19 to birch, 17 to grasses, 12 to molds, 2 to olive, and 1 to cypress. There was no difference between mono- and polysensitized patients concerning the duration of rhinitis (6 ± 2.14 years vs 6 ± 3.7). Severity of symptoms was higher in polysensitized patients than in monosensitized (p<0.05); in addition, there was a difference among monosensitized patients: Parietaria-allergy induces the most severe symptoms.
  
  
  CONCLUSIONS
  This study conducted in a large AR population might suggest that monosensitized and polysensitized AR patients could constitute two different categories. In addition, the specific type of allergy may condition the clinical feature.
authors.affiliation: Department of Internal Medicine, University of Genoa, Genoa, Italy. gio.cip@libero.it
authors.forename: Giorgio
authors.initials: G
authors.lastname: Ciprandi
authors.forename: Ignazio
authors.initials: I
authors.lastname: Cirillo
mesh_terms: D000328:Adult; D000485:Allergens / Q000276:immunology*; D000818:Animals; D001249:Asthma / Q000276:immunology; D029662:Betula / Q000276:immunology; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D029781:Cupressus / Q000276:immunology; D005260:Female; D005658:Fungi / Q000276:immunology; D006801:Humans; D007558:Italy / Q000453:epidemiology; D008297:Male; D031658:Olea / Q000276:immunology; D032403:Parietaria / Q000276:immunology; D006109:Poaceae / Q000276:immunology; D039981:Pyroglyphidae / Q000276:immunology; D006255:Rhinitis, Allergic, Seasonal / Q000453:epidemiology* / Q000276:immunology*; D012720:Severity of Illness Index; D055815:Young Adult
chemical_list: D000485:Allergens