225 Review article Nasal provocation test: how to maximize its clinical use? Pongsakorn Tantilipikorn 1 , Pakit Vichyanond 2 and Jean Silvain Lacroix 3 Summary In order to diagnose allergic rhinitis (AR), skin prick tests and serum specific IgE level are the most common used methods. But there are some conditions which the results of both methods do not correlate with the clinical presentation of AR. Nasal provocation test is the method of detecting local IgE at the shock organ. There are some variations of NPT in terms of dosage, allergen administration, evaluation and scoring system. This article summarized the usefulness of NPT, its indication and contraindication, dosage and instillation techniques for allergens and evaluation of outcome in the hope that if we can standardize the procedure and make it easier to perform, NPT will be applied more in clinical practice. In addition normal values among Asian ethnics are presented for appropriate interpretation of the test (Asian Pac J Allergy Immunol 2010;28:225-31) Key words: Allergic rhinitis, Diagnosis, Skin prick test, Nasal provocation test, Peak nasal inspiratory flow, Acoustic rhinometry, Rhinomanometry Introduction Skin prick tests are recommended as the test of choice for the diagnosis of allergic rhinitis (AR) due to its simplicity and reproducibility 1 . In cases when skin prick testing is not possible, such as inability to discontinue oral antiallergic drug, responsible practitioners may request for serum specific IgE as an alternative diagnostic test. Although skin tests and serum specific IgE levels are the most reliable method for determining specific hyperreactivity and sensitization, some discrepancies between serum specific IgE and local production specific IgE in the nasal mucosa have been observed 2 . For example, positive skin tests and increased serum level of specific IgE could be present in individuals who do not have any clinical manifestations of allergic disease 3 . In contrast, some patients with symptoms of AR do not have any positive skin tests or serum specific IgE. In such cases, the nasal provocation test (NPT) with specific allergens could help in the establishment of reliable diagnosis of AR. Upon instilling the culprit allergen into the nasal cavities an allergic reaction is produced. Nasal provocation with specific allergens is therefore considered the gold standard for the diagnosis of AR. However, the NPT is not popular in clinical practice and is limited to tertiary care centers due to its complexity and inability to test more than one allergen at once. Moreover, results of skin prick tests and serum specific IgE levels could not be correlated with NPT response in some investigations 4-6 . Such drawback could be due to several reasons including the absence of universally accepted method for NPT procedures. In addition, the dosage of available provocation extracts may vary from one manufacturer to another. The scoring and recording criteria for defining positive NPT reaction are varied as well as the objective tools to measure the degree of nasal blockage. Currently, the widely accepted From the 1 Division of Rhinology & Allergy, Department of Otorhinolaryngology 2 Division of Allergy & Clinical Immunology, Department of Pediatrics, Faculty of Medicine Siriraj Hospital , Mahidol University, Bangkok, Thailand., 3 Rhinology-Olfactology Unit, University Hospital, Geneva, Switzerland Corresponding author: Pongsakorn Tantilipikorn Email: siptv@mahidol.ac.th Submitted date: 28/10/2010 Accepted date: 17/11/2010 Downloaded from http://apjai.digitaljournals.org . For personal use only. No other uses without permission.