Comparison of Nasal Mucus Metabolites in Chronic Rhinosinusitis With and Without Polyps and Healthy Controls.

OBJECTIVE: To identify differences in nasal mucus metabolites from patients with chronic rhinosinusitis with nasal polyps (CRSwNP) and chronic rhinosinusitis without nasal polyps (CRSsNP) and healthy controls. STUDY DESIGN: Cross-sectional. SETTING: Single institution tertiary care facility. METHODS: Patients were assigned to groups based on the appearance of normal mucosa (control [n = 5]), diseased mucosa ([CRSsNP] [n = 6]), or polypoid mucosa ([CRSwNP] [n = 4]), respectively. Mucus was collected on swabs. Nasal mucus metabolites were quantified via untargeted metabolomics using liquid chromatography-mass spectrometry (LC-MS) for detection of all metabolites observable with the method. Metabolites in biochemical pathways implicated in sinonasal disease were further selected for analysis. RESULTS: In the glycerophospholipid pathway, glycerophosphocholine and glycerol-3-phosphate were significantly elevated in controls (C) compared to the CRSwNP and CRSsNP groups (false discovery rate [FDR] = 0.03, C vs CRSwNP fold change [FC] = 3.83, C vs CRSsNP FC = 3.92 and FDR = 0.02, C vs CRSwNP FC = 3.05, C vs CRSsNP FC = 3.50, respectively). In the sphingolipid pathway, C24-OH sulfatide and dihydroceramide were significantly elevated in CRSwNP compared to CRSsNP and control mucus (FDR = 0.01, CRSwNP vs C FC = 146.75, CRSsNP vs C FC = 45.55, CRSwNP vs CRSsNP FC = 3.22 and FDR = 0.05, CRSwNP vs C FC = 4.40, CRSwNP vs CRSsNP FC = 2.72, respectively). CONCLUSION: Glycerophosphocholine and sphingolipid nasal mucus metabolites differed between patients with subtypes of CRS and controls. Nasal mucus metabolites may aid in differentiating subtypes of sinusitis.