Bronchial allergen provocation (BAP) may be useful for ruling out an asthmatic reaction induced by house dust mites in children and adolescents who have a negative nasal provocation test (NPT), yet caution is warranted due to the potential side effects associated with BAP, a study in Pediatric Allergy and Immunol suggests.
Pediatric patients (n=112) with house dust mite sensitization underwent BAP in this study. Investigators assessed decreases in forced expiratory volume in 1 second (FEV1), exhaled nitric oxide, as well as total and specific IgE. The investigators then performed NPT in 74 children (median age, 9 years) within a 12-week period of performing BAP. A total of 3 groups were created based on allergy status: 4 to 40 allergen units (AU) highly allergic, >40 to 400 AU allergic, and a Lebel score <6 at the third dose (negative).
Overall, BAP was well tolerated, yet 1 patient was admitted to the hospital for prolonged asthmatic symptoms. A total of 57 of 74 patients had positive BAP results, and 46 patients had positive NPT results (Lebel score ≥6 points). Based on these findings, 41 out of 57 patients had both positive BAP and NPT results, with a sensitivity of 71.9% (95% CI, 58.5-83.0) and a specificity of 70.6% (95% CI, 44.0-89.7). Additionally, there was a good positive predictive value of 89%. Other good predictors of an early asthmatic reaction included exhaled nitric oxide ≥10 ppb (area under the curve [AUC], 0.78), specific IgE Dermatophagoides pteronyssinus ≥25.6 kU/L (AUC, 0.76), and specific IgE Dermatophagoides farinae ≥6.6 kU/L (AUC, 0.78).
A limitation of the study included the lack of rhinomanometry use for objectively confirming the NPT results.
“For a clinician, this result is of great value,” the researchers wrote, “since a positive NPT may be a substitute for BAP in most of the cases.”
Disclosure: Several study authors declared affiliations with the pharmaceutical industry. Please see the original reference for a full list of authors’ disclosures.
Fischl A, Eckrich J, Passlack V, et al. Comparison of bronchial and nasal allergen provocation in children and adolescents with bronchial asthma and house dust mite sensitization [published online October 29, 2019]. Pediatr Allergy Immunol. doi:10.1111/pai.13147