EAACI Position paper on the standardization of nasal allergen challenges

Abstract

Nasal allergen challenge (NAC) is an important tool to diagnose allergic rhinitis. In daily clinical routine, experimentally, or when measuring therapeutic success clinically, nasal allergen challenge is fundamental. It is further one of the key diagnostic tools when initiating specific allergen immunotherapy. So far, national recommendations offered guidance on its execution; however, international divergence left many questions unanswered. These differences in the literature caused EAACI to initiate a task force to answer unmet needs and find a consensus in executing nasal allergen challenge. On the basis of a systematic review containing nasal allergen challenges of the past years, task force members reviewed evidence, discussed open issues, and studied variations of several subjective and objective assessment parameters to propose a standardized way of a nasal allergen challenge procedure in clinical practice. Besides an update on indications, contraindications, and preparations for the test procedure, main recommendations are a bilaterally challenge with standardized allergens, with a spray device offering 0.1 mL per nostril. A systematic catalogue for positivity criteria is given for the variety of established subjective and objective assessment methods as well as a schedule for the challenge procedure. The task force recommends a unified protocol for NAC for daily clinical practice, aiming at eliminating the previous difficulty of comparing NAC results due to unmet needs.

Detection of local allergic rhinitis in children with chronic, difficult‐to‐treat, non‐allergic rhinitis using multiple nasal provocation tests

“…Nasal provocation tests were unilateral with 0.07 mL (equivalent to one puff) of normal saline or the challenge solution (volume recommended by the manufacturer [LETI]) sprayed through a nasal dosing pump pointed toward the middle/inferior turbinate at 15‐minute intervals. NPT details and exclusion criteria complied with international guidelines . Four initially freeze‐dried and then reconstituted allergen solutions of D pteronyssinus (100 HEP/mL), A alternata (30 HEP/mL), O europea (30 HEP/mL), and P pratense (30 HEP/mL) were used.…”

“…Multiple nasal provocation tests were performed according to the protocol developed by Rondon et al outside of the olive and grass pollen season (typically May to July for Greece) and at days the patients were asymptomatic (or with mild symptoms if patients with perennial symptoms). In short, four prevalent aeroallergens were applied every 15 minutes with an established order depending on the length of symptoms the children/carers reported, as follows: Perennial rhinitis: P. pratense , O. europea , A. alternata , and D. pteronyssinus ; Seasonal rhinitis: A. alternata , D. pteronyssinus , O. europea , and P. pratense . …”

Sensitization to Cat: When Is Nasal Challenge Needed?

“…NCT should be indicated as a specific diagnostic confirmation of PER when there are discrepancies, or difficulties arise, in the assessment of the patient’s medical history and the results of skin and/or serological allergy testing [17]. Recent EAACI guidelines recommend NCT as fundamental, not only experimentally but also when measuring therapeutic success clinically [18], and when prescribing allergen immunotherapy (AIT) [19], especially if the culprit allergen is elusive. It is a safe and inexpensive technique that reproduces an allergic reaction in the nose under standardized and controlled conditions [20].…”

“…NCT is recommended for identifying rhinitis phenotypes and endotypes and could lead to the application of stratified and personalized medicine in the rhinitis field [21]. Currently, the only potentially disease-modifying treatment for cat allergy is AIT [19], and according to the recent EAACI position paper, NCT is considered one of the key diagnostic tools when initiating AIT [18]. …”

Reliability of a New Symptom Score in a Titrated Quantitative Conjunctival Provocation Test Supported by an Objective Photodocumentation

“…Thus, allergen provocation is an essential diagnostic technique to prove the clinical relevance of an allergic sensitization in the target organs [3-5] and is recommended by the European Medicines Agency for dose-range finding trials in allergen immunotherapy (AIT) [6]. Most often a nasal provocation test (NPT), recently standardized in a position paper of the European Academy of Allergy and Clinical Immunology (EAACI), is conducted in Europe [7]. …”