Myrsini Kaforou, PhD1; Jethro A. Herberg, PhD1; Victoria J. Wright, PhD1; et al

Distinguishing children with potentially life-threatening bacterial infections from febrile children with viral infections remains a major challenge. Herberg and colleagues,1 in a preliminary, cross-sectional study of 370 febrile children (aged <17 years) in Europe and the United States, reported that children with bacterial infection may be characterized by the difference in blood RNA expression values of 2 genes. In a recent study, Mahajan and colleagues2 reported a 66-transcript blood RNA signature that distinguished bacterial from viral infection in 279 febrile infants younger than 60 days. Young infants are at high risk of bacterial infection; diagnosis is difficult and prompt treatment important. To provide further validation of the 2-gene signature and to evaluate its performance in the infant population, we applied the signature to the RNA expression data of Mahajan et al.

JAMA