Patients previously given a diagnosis of nonallergic rhinitis (NAR) might have a new form of local allergic rhinitis (LAR) characterized by:- local production of specific IgE antibodies
- positive response to a nasal allergen provocation test (NAPT)
The researchers evaluated a NAPT protocol using multiple aeroallergens (NAPT-M) for the detection of polysensitization to several aeroallergens in patients with LAR.
A total of 25 adult patients with LAR and 25 adult patients with NAR were randomly selected (Malaga, Spain). All the patients had a history of at least 2 years of persistent rhinitis with negative skin prick test (SPT) responses and serum sIgE levels to the most prevalent aeroallergens.
How was NAPT-M testing done?
The NAPT-M testing was done bilaterally with a panel of 4 aeroallergens with freeze-dried allergen solutions of:
- D pteronyssinus
- A alternata
- O. europea
- grass pollen
Two puffs (100 mL) of the solution were applied in each nostril at 15-minute intervals.
The response to nasal challenge was evaluated based on:
- subjective parameters (VAS of nasal-ocular symptoms). Nasal obstruction, rhinorrhea, itching, sneezing, and ocular symptoms were recorded by using a visual analog scale (VAS).
- objective parameters (VOL 2-6 cm). Nasal patency was assessed by means of acoustic rhinometry with the use of an SRE 2000 rhinometer (Rhinometrics, Lynge, Denmark).
A positive NAPT-M response was considered to be an increase of 30% or greater in the total VAS score and a decrease of 30% or greater in the sum of VOL.
NAPT-Ms showed 100% concordance with the gold standard of NAPTs with a single aeroallergen. No false-positive or false-negative responses were detected.
The use of NAPT-Ms achieved 75% reduction in the total number of visits required for final diagnosis in the NAR group and a 55% reduction in the LAR group compared with NAPTs with a single aeroallergen.
Clinically relevant polysensitization to aeroallergens occurs in patients with LAR. NAPT-M is a useful, specific, sensitive, reproducible, and less time-consuming diagnostic test for the screening of patients with LAR.
References:
Nasal allergen provocation test with multiple aeroallergens detects polysensitization in local allergic rhinitis. JACI, 2011.
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