Local allergic rhinitis: a pediatric perspective.
Local allergic rhinitis (LAR) is a differentiated rhinitis phenotype defined by perennial or seasonal rhinitis symptoms without systemic atopy. The diagnosis can be made by a positive response to the nasal allergen challenge (NAC) (the gold standard for diagnosis) in the absence of skin prick test and/or serum allergenspecific immunoglobulin E. Clinical and epidemiological studies have demonstrated that LAR affects individuals from different countries, races, and age ranges. Several studies have shown that the onset of nasal symptoms occurs during childhood in a significant proportion of LAR individuals. Evidence of LAR has been growing, especially in pediatric and Asian populations. A review of the literature reveals that most LAR studies of pediatric populations have appeared in the last three years. The prevalence of LAR in children ranges from 3.7% to 66.6%, and similar to what has been observed in adults, prevalence is higher in Western countries. Publications have shown that LAR in children can be either seasonal or perennial, and diagnosis of LAR confirmed by NAC have been reported with numerous allergens (house dust mites, pollens, molds, and dander). These findings illustrate that LAR is an important differential diagnosis in children with presumed non-allergic rhinitis, and a through review of the very recent literature can contribute to the clinical identification and diagnosis of LAR in children with no evidence of systemic atopy, as well as update readers` knowledge of the topic.