Evidence demonstrates the existence of local allergic rhinitis (LAR) in nonatopic patients, although its prevalence in the rhinitis population remains unknown in children. The aim of this study was to evaluate the prevalence, clinical characteristics, and severity of LAR in children compared with patients having classical allergic rhinitis (AR) with systemic atopy or nonallergic rhinitis (NAR) with no sensitization to any of the inhaled allergens tested.
Two hundred-eighteen children between 9 months and 19 years old were enrolled and divided into 3 groups: 132 AR children, 68 NAR and 18 healthy controls. A clinical questionnaire and skin prick test (SPT) were evaluated. A nasal allergen provocation test (NPT) with Dermatophagoides pteronyssinus was performed in all subjects. The severity of ocular and nasal symptoms was recorded by visual analogue scale (VAS) of 10 cm. Each symptom was categorized as 'mild' (VAS: 0–3 cm), 'moderate' (VAS: >3–7 cm), or 'severe' (VAS > 7 cm).
In the AR group, 43/132 (32.6%) patients presented a positive response to NPT. In the NAR group, 11/69 (15.9%) patients had a positive response to NPT. NPT was negative in 17/18 healthy controls (94.4%). The majority of rhinitis patients had moderate–severe nasal symptoms. LAR and AR subjects had a similar pattern of nasal symptoms in frequency and severity. However, significant differences were detected between LAR and NAR.
Local allergic rhinitis is a prevalent entity in patients evaluated with rhinitis. LAR and AR subjects had a similar pattern of nasal symptoms in frequency and severity. Conventional skin tests were significantly well correlated with nasal provocation tests.
Key Words: Local allergic rhinitis, Nasal provocation test, Children