Study on the potential diagnostic value of metabolomics changes in different biological fluids for aspiration pneumonia.

BACKGROUND: Aspiration pneumonia (AP) is a type of lung inflammation caused by the aspiration of food, oropharyngeal secretions, or gastric contents. This condition is particularly common in older adults and individuals with impaired swallowing or consciousness. While the diagnosis of AP relies on clinical history, swallowing assessments, and imaging, these methods have significant limitations, often leading to underdiagnosis or misdiagnosis. Reliable biomarkers for AP diagnosis are lacking, making early detection and treatment challenging. METHODS: Nineteen patients diagnosed with pneumonia were included in this study, divided into two groups: AP (n = 10) and non-AP (n = 9). Biological fluid samples, including bronchoalveolar lavage fluid (BALF), saliva, serum, sputum, and urine, were analyzed using non-targeted liquid chromatography with tandem mass spectrometry (LC-MS/MS). Differential metabolites were identified using fold change analysis, statistical significance, and receiver operating characteristic (ROC) curve analysis to evaluate their diagnostic potential. Spearman correlation was used to examine the relationship between selected metabolites and clinical parameters. RESULTS: Significant metabolic differences were found between AP and non-AP patients, with many different metabolites identified across biological fluids. Dehydroepiandrosterone sulfate (DHEAS), Androstenediol-3-sulfate (ADIOLS), and beta-muricholic acid were identified as key biomarkers through fold change analysis and ROC curve analysis, showing consistent increasing or decreasing trends in BALF, sputum, and serum samples. DHEAS was found to be negatively correlated with the Acute Physiology and Chronic Health Evaluation II (APACHE II) (r = - 0.619, p = 0.005) in BALF sample. The area under curve (AUC) values showed that these molecules could serve as effective biomarkers for AP. CONCLUSIONS: This study identifies DHEAS, ADIOLS and beta-muricholic acid as promising biomarkers for AP, with the potential to improve early diagnosis and treatment. These findings underscore the clinical value of metabolomics in developing diagnostic tools for AP, facilitating better clinical management and patient outcomes. Further research is required to validate these biomarkers in larger cohorts and explore their mechanistic roles in AP pathophysiology.