The Relevance of Nasal Provocation Testing in Children with Nonallergic Rhinitis.

Background: It is important to understand that allergic rhinitis, whether seasonal or perennial, may be difficult to distinguish clinically from the nonallergic forms of rhinitis.

Objective: This study aimed to investigate the presence of local allergic rhinitis (LAR) in children who have allergic rhinitis symptoms in the absence of skin test positivity and specific IgE by performing a nasal provocation test (NPT).

Methods: Our study followed a case-controlled, prospective design. Twenty-eight patients and 30 healthy children were included in the study in a pollen-free season. The NPTs with a grass mix, Dermatophagoides pteronyssinus (DP) and D. farinae (DF) allergens were performed with an interval of 1 week. The total symptom score and visual analog scale, nasal eosinophilia and pulmonary function tests were evaluated before and after each NPT. The change to nasal flow and resistance was recorded by anterior rhinomanometry.

Results: The symptom frequencies before the NPTs were as follows: nasal congestion 100%; itching 82.1%; rhinorrhea 75% and sneezing 71.4%. The NPT was positive in 7 (25%) patients. In the NPT-positive group there was a statistically significant decrease in nasal flow at the concentrations of 10 and 100 IR/ml for DF (p = 0.026, p = 0.031, respectively). In the NPT-positive group total nasal resistance for DP was increased at the concentrations of 0.1 and 10 IR/ml, and for DF at 10 and 100 IR/ml (p = 0.049, p = 0.041, p = 0.022, p = 0.035, respectively).

Conclusions: We emphasize that the diagnosis of LAR should be taken into consideration by pediatricians and pediatric allergy specialists.