How to do nasal allergen provocation test to diagnose local allergic rhinitis?

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.

Image source: Wikipedia, Creative Commons license.

1 comment:

  1. I have a severe dog allergy, with negative skin & blood tests! I used to have positive allergy tests but no longer. Is there anyone who can help with it?
    My only symptom is an "allergy fog" that goes on for several days after exposure, and rarely, postnasal drip. No noticeable congestion, so I wonder if the method above would work. I do have immediate reactions though.
    My family doc is willing to prescribe nasal steroids etc. for me. They help a little.
    I'm trying to avoid dog exposure, hoping that will help. The allergy may be related to chronic exposure to allergens.

    ReplyDelete

Blog Widget by LinkWithin