title: The diagnostic approach to immediate hypersensitivity in patients with allergic rhinitis; a comparison of nasal challenges and serum rast.
abstract: Nasal challenges performed in 182 patients with allergic rhinitis revealed 273 positive and 125 negative responses to house dust, grass pollen, cat and dog danders and aspergillus fumigatus, which all correlated with disease history and intracutaneous tests. In these randomly selected patients the specific IgE antibodies in the serum to the same allergens as those used for nasal challenges were determined quantitatively by serum RAST. Additionally, blood and nasal eosinophilia were recorded during the nasal provocation tests. In all 273 positive challenges protection tests with disodium cromoglycate (DSCG) were also performed. In 24.2% of the positive nasal challenges serum RAST was found positive and in 18.7% of them serum RAST was doubtful. In 52% of the negative nasal challenges negative serum RAST also occurred. No significant correlation was found between serum RAST and nasal challenges (X2 = 0.92; d.f. = 1; 0.20 less than p less than 0.40). No significant correlation was found between serum RAST and nasal challenges for individual allergens tested. Since the nasal provocation test is an in vivo technique, it is likely to be of value for the diagnostic confirmation of the allergic component (due to immediate hypersensitivity) in patients with allergic rhinitis than serum RAST alone. Although serum RAST cannot substitute the nasal provocation tests, it may be a useful supplementary diagnostic parameter.
mesh_terms: D006801:Humans; D006969:Hypersensitivity, Immediate / Q000175:diagnosis*; D009299:Nasal Provocation Tests; D011852:Radioallergosorbent Test; D011863:Radioimmunoassay; D012221:Rhinitis, Allergic, Perennial / Q000175:diagnosis*; D006255:Rhinitis, Allergic, Seasonal / Q000175:diagnosis