Prevalence and Clinical Characteristics of Local Allergic Rhinitis in Children Sensitized to House Dust Mites.

Objective: The prevalence of local allergic rhinitis (LAR) in nonatopic children remains unknown. This study aimed to determine the prevalence, clinical characteristics, and severity of LAR in children in comparison to classical allergic rhinitis (AR) and nonallergic rhinitis (NAR).

Study Design: A total of 145 children (aged 1-18 years) were enrolled and classified into 3 groups (AR, NAR, and LAR) based on a skin prick test (SPT) and a nasal provocation test (NPT) with house dust mite, i.e., Dermatophagoides pteronyssinus. NPT positivity was defined as a symptom score ≥2 standard deviations (SDs) above the healthy control score.

Results: Eighty-one children had AR (55.9%), and 64 (44.1%) had symptoms of rhinitis with negative SPT; 59 NAR (40.7%) and 5 LAR (3.4%) children were identified. The κ score for agreement between the SPT and the NPT results was 0.778 (95% CI 0.726-0.830, p < 0.001). A significant correlation was observed between wheal diameter and maximum nasal symptom score provoked by D.pteronyssinus (rho = 0.589, p < 0.001). Nasal severity according to the ARIA guideline did not show any differences in the 3 groups (p = 0.693). The AR group was older than the LAR and NAR groups (AR > LAR > NAR, p = 0.003).

Conclusions: Despite the evidence to support the existence of LAR in pediatric populations, we found that its prevalence was relatively low, possibly due to the high rate of agreement between SPT and NPT. Further investigations are needed to identify immunological as well as clinical implications of LAR.