Metabolomics is a relatively new technology that involves the measurement of an organism’s global metabolic response to some physiologic stress. The study of this technology is gaining momentum, as measurement of a person’s metabolic profile in easily accessible biological fluids can help distinguish disease states from non-disease states earlier. Thus, patients could receive appropriate therapies earlier, which can improve outcomes in cases such as pneumonia and sepsis. In the May 2013 issue of Respiratory and Critical Care Medicine, the authors used 1H proton nuclear magnetic resonance spectroscopy to measure the concentrations of 58 different metabolites in serum samples taken from 140 pediatric subjects from 11 different institutions.
By first applying principal component analysis and then partial least squares discriminant analysis methods to the data, the authors were able to successfully delineate the metabolic scores of healthy control subjects from systemic inflammatory response syndrome (SIRS) and septic groups on a 3-D score scatter plot. Although there was some overlap between the SIRS and septic groups, overall, the studied groups were well clustered. The authors discovered that by measuring these metabolites and applying these statistical methods, they could more accurately predict mortality rates compared to the conventionally used physiologically-based Pediatric Risk of Mortality III-Acute Physiology Score model or procalcitonin levels. Further study with a larger cohort of patients is needed, as it may lead to even better delineation of metabolic profiles and diagnoses. Read the full Concise Critical Appraisal.