Local allergic rhinitis in children: clinical characteristics and role
of basophil activation test as a diagnostic tool.
Background Local allergic rhinitis (LAR) is a condition involving a
localized nasal allergic response in absence of systemic atopy. We aimed
to describe clinical characteristics of LAR and non-allergic rhinitis
(NAR) pediatric patients, their clinical evolution over a 7-year
follow-up period and to study the role of basophil activation test
(BAT), for the diagnosis of LAR. Methods Forty-four children with
non-allergic rhinitis (NAR) were included (24 males, 20 females, aged
under 15 years). Nasal allergen provocation test (NAPT) and BAT were
performed with Dermatophagoides pteronyssinus and Phleum
pratense. Results Seven patients (16%) were diagnosed of LAR. Seven
reacted to D pteronyssinus and one also to P pratense. All
LAR and 86% of NAR patients presented perennial symptoms. Fifty-seven
percent of NAR and LAR patients referred persistent symptoms. Three LAR
patients associated conjunctival symptoms. BAT was positive after
stimulation with D pteronyssinus only in one LAR patient. On
follow-up, 3 LAR patients and 10 of the 25 NAR patients who agreed to be
retested, presented systemic sensitization. Conclusions LAR should be
considered in children with NAR. Almost half of children with LAR and
one fourth of NAR children will develop systemic sensitization over
time. BAT shows low sensitivity for the diagnosis of LAR in children.
Key message: Since sixteen percent of initially diagnosed as
non-allergic rhinitis children present local allergic rhinitis, we
suggest performance of nasal provocation test in those cases to achieve
a correct diagnosis. Basophil activation test seems to be less sensitive
for the diagnosis of local allergic rhinitis in children than in adults.
Follow up over would be interesting since a significant number local
allergic rhinitis children and non-allergic rhinitis children will
eventually develop systemic sensitization to aeroallergens.