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Background: Two different allergic rhinitis (AR) symptom phenotype classifications exist. Treatment recommendations are based on intermittent-persistent (INT-PER) cataloging, but clinical trials still use the former seasonal AR-perennial AR (SAR-PAR) classification. This study was designed to describe how INT-PER, mild-moderate/severe and SAR-PAR of patients seen by allergists are distributed over the different climate zones in a (sub)tropical country and how these phenotypes relate to allergen sensitization patterns. Methods: Six climate zones throughout Mexico were determined, based on National Geographic Institute (Instituto Nacional de Estadística y Geografía) data. Subsequent AR patients (2-68 years old) underwent a blinded, standardized skin-prick test and filled out a validated questionnaire phenotyping AR. Results: Five hundred twenty-nine subjects participated in this study. In the tropical zone with 87% house-dust mite sensitization, INT (80.9%; p < 0.001) and PAR (91%; p = 0.04) were more frequent than in the subtropics. In the central high-pollen areas, there was less moderate/severe AR (65.5%; p < 0.005). Frequency of comorbid asthma showed a clear north-south gradient, from 25% in the dry north to 59% in the tropics (p < 0.005). No differences exist in AR cataloging among patients with different sensitization patterns, with two minor exceptions (more PER in tree sensitized and more PAR in mold positives; p < 0.05). Conclusion: In a (sub)tropical country the SAR-PAR classification seems of limited value and bears poor relation with the INT-PER classification. INT is more frequent in the tropical zone. Because PER has been shown to relate to AR severity, clinical trials should select patients based on INT-PER combined with the severity cataloging because these make for a better treatment guide than SAR-PAR. [ABSTRACT FROM AUTHOR]

Background: In perennial allergic rhinitis (PAR), the skin-prick test (SPT) is a good diagnostic tool to identify the specific allergens. A nasal provocation test (NPT) is used to identify allergens and to confirm the diagnosis. The aim of this study was to determine the optimal cutoff values of symptom and peak nasal inspiratory flow (PNIF) changes after dust-mite NPT for predicting PAR. We also studied the relationship of the changes of symptoms in NPT and the wheal size of SPT. Methods: One hundred five patients with perennial rhinitis underwent the NPT to Dermatophagoides pteronyssinus and the SPT. The NPT was assessed by changes in symptoms and PNIF. The optimal cutoff values of the symptoms score and PNIF changes after the NPT for predicting the SPT were determined using a receiver operating characteristic (ROC) curve. The relationship of the wheal sizes of SPT and the changes from the NPT were analyzed. Results: Forty-eight patients had a positive SPT to D. pteronyssinus, of whom 33 patients had a positive NPT by increases of the symptom score. Twenty patients had a positive NPT by decreases of PNIF. The area under the ROC curve was 0.85 for symptom score changes and it was 0.612 for PNIF changes. There was a significant correlation between the wheal size of the SPT and symptom changes in the NPT. Conclusion: Nasal provocation is a valuable test to confirm the diagnosis of D. pteronyssinus allergy, especially when the wheal from the SPT is small. The symptom change after the house-dust mite NPT is better than the PNIF change for predicting the PAR. [ABSTRACT FROM AUTHOR]