Local allergy in the atopic march: new insights into adenotonsillar hypertrophy.

Adenoid hypertrophy (AH) and combined adenotonsillar hypertrophy (ATH) are primary causes of childhood sleep-disordered breathing (SDB), and they are strongly correlated with atopic diseases affecting the respiratory mucosa. Allergen sensitization, class-switching of B cells, and IgE production in the adenotonsillar tissue, namely local atopy, are crucial steps in the pathogenesis of allergic rhinitis (AR) and asthma. The adenotonsillar tissue is also responsible for a considerable part in circulating specific IgE, potentially contributing to the pathogenesis of atopy in other organs. Atopic children experience fewer benefits from adenotonsillectomy compared to their nonatopic counterparts. However, this surgical intervention is effective in relieving both obstructive and allergic symptoms in children with concomitant ATH and AR or asthma. Adjunctive treatments such as allergen immunotherapy reduce the risk of recurrence in atopic children undergoing adenotonsillar surgery. This review focuses on the evidence linking local adenotonsillar IgE sensitization and the atopic march and its implications in the treatment and outcomes of both conditions.