Disrupted glutamate–gaba balance in children with adenoid hypertrophy:a targeted metabolomic and clinical correlation study

Purpose: The molecular basis of adenoid hypertrophy (AH) has not yet been fully elucidated. This study aims to investigate specific plasma amino acid alterations in children with AH and evaluate their associations with systemic inflammatory markers. By characterizing the metabolic profile of AH and identifying potential amino acid signatures, we sought to uncover metabolic biomarkers associated with systemic effects of upper airway obstruction, ultimately contributing to improved diagnostic and therapeutic strategies in pediatric patients. Methods: This prospective study included pediatric patients with upper airway obstruction due to adenoid hypertrophy, confirmed by endoscopic examination and clinical symptoms, and scheduled for adenoidectomy, along with age- and sex-matched healthy controls. Targeted metabolomic analysis of plasma amino acid levels was performed using liquid chromatography–mass spectrometry (LC–MS/MS). To identify significant metabolic alterations and assess their clinical relevance, statistical comparisons, correlation analyses, and pathway enrichment mapping were conducted. Results: Among the 36 amino acids analyzed, eight exhibited significant differences between groups. Glutamic acid, phenylalanine, and leucine were elevated in AH patients, while GABA, tryptophan, alanine, citrulline, and anserine were decreased. Pathway analysis highlighted dysregulation in alanine, aspartate, and glutamate metabolism. Clinical correlations suggest potential links to endothelial dysfunction, excitotoxicity, and neurodevelopmental vulnerability. Conclusion: The study presents the first metabolomic characterization of systemic responses related to obstruction-causing adenoid hypertrophy, implicating amino acid dysregulation as a contributor to both local proliferation and multisystem complications. These findings offer insight into disease mechanisms, propose early biochemical markers for adenoid hypertrophy-induced airway obstruction, and support the development of targeted metabolic and microbiota-informed therapies.