Circulating 25-hydroxyvitamin D, nasopharyngeal airway metabolome, and bronchiolitis severity

Area of Science:

• Pediatric Pulmonology
• Nutritional Immunology
• Metabolomics

Background:

• Low circulating 25-hydroxyvitamin D (25OHD) is a known risk factor for acute respiratory infections in children.
• The relationship between 25OHD, airway functional molecules, and clinical outcomes in bronchiolitis remains largely unexplored.

Purpose of the Study:

• To investigate the association between serum 25OHD levels and airway metabolomic profiles in infants hospitalized with bronchiolitis.
• To identify specific airway metabolites linked to 25OHD levels and clinical severity.

Main Methods:

• Prospective multicenter study involving 144 infants (<1 year) hospitalized with bronchiolitis.
• Measurement of serum 25OHD levels and comprehensive metabolomic profiling of nasopharyngeal airway samples.
• Statistical analysis to identify metabolites associated with 25OHD, vitamin D-binding protein, and clinical outcomes like positive pressure ventilation.

Main Results:

• 254 metabolites were identified in airway samples.
• A distinct set of 20 metabolites was associated with lower serum 25OHD and higher vitamin D-binding protein levels.
• Nine specific metabolites, including glycerophosphocholines and sphingomyelins, were significantly associated with an increased risk of requiring positive pressure ventilation.

Conclusions:

• Vitamin D-related airway metabolites are identified in infants with bronchiolitis.
• These metabolites are associated with the severity of bronchiolitis and the need for respiratory support.
• Findings suggest a potential role for vitamin D-mediated metabolic pathways in pediatric respiratory illness severity.