RESUMO
BACKGROUND: Local allergic rhinitis (LAR) is a localized nasal allergic response in the absence of systemic atopy that is characterized by local production of specific immunoglobulin E (sIgE), and a positive response to NAPT (nasal allergen provocation test). OBJECTIVE: The objective of this study is to investigate the prevalence of LAR in adults with chronic rhinitis (CR) and negative skin prick test to Dermatophagoides pteronyssinus (Dp), and to assess the clinical characteristics of LAR, comparing to non-allergic rhinitis (NAR). METHODS: Patients with history of CR with negative skin prick test (SPT) to Dp were recruited during January 2015-April 2016. Demographic and clinical data were obtained, and then a NAPT with Dp was performed. The immediate response to NAPT-Dp was assessed using clinical symptom score, visual analogue scale, peak nasal inspiratory flow, and acoustic rhinometry. Nasal lavage was evaluated for nasal sIgE and tryptase level. RESULTS: Sixty-two CR patients were recruited. NAPT-Dp was positive in 15/62 (24.2%) of CR patients. Most LAR patients were female (73.3%), and the mean age of all patients was 36.1 ± 10.4 years. Our evaluation of patient characteristics revealed sneezing to be the only evaluated factor to be statistically significantly different between groups [odds ratio (OR): 7.75, 95% confidence interval (CI): 1.91-31.48; p = 0.002]. CONCLUSIONS: The prevalence of LAR to Dp in Thai adults with CR and negative skin prick test was 24.2%. Most LAR patients had moderate-severe persistent severity. The clinical characteristics of LAR, sneezing was shown to be a significantly dominant symptom in LAR than in NAR.
