Gastroesophageal Reflux and Recurrent Wheezing in Preschool Children: An Update on Pathophysiology, Diagnosis, and Management

Recurrent wheezing represents a significant cause of respiratory morbidity in preschool children. While viral infections in the context of immune dysregulation are primary drivers, gastroesophageal reflux disease (GERD) and laryngopharyngeal reflux (LPR) are increasingly recognized as critical triggers. The link between GERD and respiratory symptoms has historically been controversial; however, recent advances necessitate a re-evaluation of this relationship. This review critically analyzes the pathophysiological nexus between reflux and airway hyperresponsiveness, emphasizing the dual mechanism of microaspiration and vagal reflex, while integrating the concept of reverse causality (where respiratory effort actively exacerbates reflux). We highlight that the “respiratory reflux” phenotype in preschoolers is often characterized by non-acid and proximal episodes, which standard pH-metry fails to detect. Consequently, we discuss the diagnostic shift towards multichannel intraluminal impedance-pH (MII-pH) monitoring and the incorporation of novel metrics defined by the Lyon Consensus 2.0 (MNBI, PSPW index), alongside specific biomarkers such as pepsin. Finally, we propose a phenotype-driven management algorithm, differentiating between acid-suppressive therapy and alginate-based interventions, to mitigate disease burden and improve clinical outcomes in refractory cases.