Local Allergic Rhinitis in Pediatric Patients: is IgE Dosage in Nasal Lavage Fluid a Usefull Diagnostic Method in Children?

Local Allergic Rhinitis (LAR) is an emerging disease. However, its incidence in the pediatric population has not yet been studied. The gold-standard for the diagnosis is the nasal provocation test that is not everywhere available and difficult to apply in children. The aim of our study is to evaluate the nasal lavage fluid IgE as a biomarker of LAR in children. 54 pediatric patients [IQR 4.0-12.0 years] were divided into 3 groups: study group (26 children with rhinitis symptoms and without evidence of systemic atopy); allergic rhinitis (AR) group (15 children) and 13 healthy controls (HC). Every child was subjected to nasal lavage using 2 ml/nostril of the physiologic saline solution, that was therefore analyzed by ImmunoCAP to obtain the IgE concentration. Rhinofibroscopy and nasal cytology were performed. Our data show the presence of higher value of nasal lavage fluid IgE (average of 6.005 UI/ml; range: 4.47-7.74 UI/ml) in 16 out of 26 patients of the study group who therefore may be classified as affected by LAR. We observed a statistically significant difference (P< 0.0001) between NAR/HC group and LAR group, identifying a cut-off of 3.85 UI/ml. Finally, we found a better response to previous AR therapy in the LAR group than in the NAR group. Our data show the high incidence of LAR in pediatric patients previously classified as NAR. The measurement of IgE in nasal lavage fluid may be considered an easy and rapid method for the diagnosis of LAR in children. Besides, our data adds confirmatory evidences about the good response of LAR children to the classic AR therapy.