Diagnostic value of the nasal provocation test with Dermatophagoides pteronyssinus in childhood asthma

We aimed to determine whether the nasal provocation test (NPT) with allergen could be used as a diagnostic test in asthmatic children with or without allergic rhinitis, and whether it had any effects on pulmonary function tests and arterial oxygen saturation (SaO₂) values. Therefore, 25 asthmatic outpatients sensitive to Dermatophagoides pteronyssinus (Dp), aged 6–17 years, 12 having allergic rhinitis, and 10 nonatopic children as a control group were challenged intranasally with solution containing Dp extract by administration of a total dose of 800–1000 AU to both nasal cavities. Before the test and 10 min and 20 min after the administration of the allergen intranasally, the nasal expiratory peak flow (NEPF), pulmonary function tests, and SaO₂ were measured. In the NPT, a decrease of 20% or more in NEPF and occurrence of nasal symptoms were considered to be positive. NPT was positive in all the asthmatic patients with or without allergic rhinitis, while all the children in the control group had a negative test. Compared to values prior to the test, values of FEV₁, (forced expiratory volume in 1 s) and SaO₂ showed no statistically significant decrease, and no clinically significant asthmatic reaction was observed in any of the groups. Our study suggests that in asthmatic children with or without allergic rhinitis, the NPT with allergen is a simple, safe, and useful diagnostic test.