RNA Biosignatures and the Febrile Infant

Investigators from multiple institutions conducted a study to assess the potential of using RNA “biosignatures” (patterns of gene expression in blood leukocytes) to diagnose bacterial infections in febrile infants ≤60 days old. Infants from 22 emergency departments were enrolled in the study if they had a temperature >38°C and had a blood culture obtained; other laboratory testing was performed at the discretion of the examining physician. A random sample of patients with and without bacterial infections was selected for RNA biosignature analysis. Blood from a sample of well afebrile infants was also collected for analysis. Microarray analysis of blood leukocytes was done to compare patterns of gene expression (RNA biosignature) in patients with culture-proven bacterial infections and those without bacterial infections, with particular focus on genes related to inflammation and interferon. Microarray samples were divided into training and test sets. Differential …