Does specific immunotherapy injection cause an increase in bronchial reactivity?
BACKGROUND
Several well-controlled studies have proven the clinical benefit of specific immunotherapy (SIT) for seasonal allergic rhinitis (AR). However, whether subcutaneous SIT injection could cause a transient increase in bronchial reactivity (BR) remains unknown.


OBJECTIVE
To investigate whether subcutaneous SIT injection, either during or outside the pollen season, could cause an increase in BR in children with pollen allergy.


METHODS
Twenty-two children (mean age 13.6 +/- 0.7 years) with AR who were receiving maintenance SIT for 15 months were included in the study. Pre-injection BR of the patients was evaluated with methacholine provocation test immediately before maintenance dose of SIT during the peak pollen season and outside the season. The post-injection test was administered 24 hours after SIT injection.


RESULTS
There was no difference in FEV1 measures recorded during [98(93-109)%] and outside [102(96-111)%] the pollen season. There was no significant difference between pre- [64(7-64) mg/mL] and post-allergen injection [32(7.5-64) mg/mL] BR outside the pollen season (p = 0.9). A trend towards improvement following allergen injection [64(5.4-64)] as compared to pre-allergen injection [14.6(3.5-64)] was shown during the pollen season (p = 0.053). Although PC20 measures in the pollen season were lower than outside the season, the difference was not significant. The percentage of the patients with bronchial hyperreactivity was 62% during and 43% outside the season.


CONCLUSIONS
SIT injections both during and outside the pollen season cause no increase in BR in children with AR. This calls into question the necessity of empirical dose reduction during the pollen season.
Keskin
Ozlem
O
Pediatric Allergy and Asthma Unit, Ihsan Dogramaci Children's Hospital, Hacettepe University School of Medicine, Ankara, Turkey.
Tuncer
Ayfer
A
Yildirim
Sefika
S
Bursali
Burcu
B
Adalioglu
Gonul
G
Sekerel
Bulent E
BE
D000293:Adolescent; D000818:Animals; D016535:Bronchial Hyperreactivity / Q000276:immunology*; D002648:Child; D003888:Desensitization, Immunologic / Q000009:adverse effects* / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D006109:Poaceae / Q000009:adverse effects*; D011058:Pollen / Q000009:adverse effects*; D006255:Rhinitis, Allergic, Seasonal / Q000628:therapy*