A gene-signature pattern can distinguish sepsis from sterile inflammation, investigators say. The gene pattern may help with objective assessment and monitoring of patients, Dr. Purvesh Khatri, of Stanford University School of Medicine, Palo Alto, California, told Reuters Health by email.

As reported online May 13 in Science Translational Medicine, Dr. Khatri and colleagues examined data on more than 2,900 blood samples from more than 1,300 patients in 27 different data sets. The patients either had sepsis when first admitted to the hospital or were diagnosed with it later, and healthy controls.

The team eventually identified 11 genes that were differentially expressed across all discovery cohorts with “excellent diagnostic power.” The discovery cohorts included 663 patient samples from 9 cohorts created from 10 data sets. The researchers then confirmed this 11-gene signature in an additional 18 cohorts comprising more than 1,800 patient samples.

“For biologists,” continued Dr. Khatri, “we have identified a set of genes not previously known to be involved in sepsis that may yield new insights into the difference in the host response to infection versus tissue trauma.”

“For bioinformaticians and computational biologists,” he went on to say, “the multi-cohort analysis framework described in the manuscript will be of significant interest as it illustrates how large amounts of data available in public repositories can be reused and repurposed to address significant problems in human health by better representing the molecular heterogeneity of a phenotype in addition to increasing the sample size.”

He added, “Our analysis is the largest use of gene expression data to examine the issue of robustly separating sterile inflammation from sepsis.”

The researchers call for further studies, but conclude, “Optimizing a clinical assay for this gene set to get results within a window of clinical relevance should be feasible.”
Finding the gene set “also underscores the need for considering a non-infected patient cohort to establish an optimal cutoff at different times since admission in future prospective trials in sepsis,” Dr. Khatri said.

The authors reported no specific study funding. Two authors disclosed possible patent protection for the 11-gene set through Stanford University.