“It’s extremely difficult to interpret what’s causing a respiratory tract infection, especially in very ill patients who come to the hospital with a high fever, cough, shortness of breath, and other concerning symptoms,” noted senior study investigator Ann Falsey, M.D., professor and interim chief of the infectious diseases division at URMC’s Strong Memorial Hospital. “My goal is to develop a tool that physicians can use to rule out a bacterial infection with enough certainty that they are comfortable, and their patients are comfortable, foregoing an antibiotic.”
To reiterate, the ability of clinicians to discriminate between bacterial and viral infections among their patients is critical, not only to administer the appropriate therapeutic intervention but to help quell the rise in antibiotic resistance stemming from overuse. Unfortunately, ailments such as lower respiratory tract infections (LRTIs) symptomatically present with similar clinical symptoms, regardless of the root pathogen—making proper diagnosis difficult.
According to the CDC, there are at least 2 million infections and 23,000 deaths each year in the United States attributable to antibiotic resistant bacteria. Now, a new study by investigators at the University of Rochester Medical Center (URMC) has yielded a way to Discriminate between Bacterial and Viral Infections by making use of
RNA sequencing (RNA-Seq) and transcriptomic analysis.“We evaluated whole blood profiling using RNASeq to discriminate infectious agents in adults with microbiologically defined LRTI,” the authors wrote. “Hospitalized adults with LRTI symptoms were recruited. Clinical data and blood were collected, and comprehensive microbiologic testing performed. Gene expression was measured using RNASeq and qPCR [quantitative PCR]. Genes discriminatory for bacterial infection were identified using the Bonferroni-corrected Wilcoxon test. Constrained logistic models to predict bacterial infection were fit using screened LASSO. We enrolled 94 subjects who were microbiologically classified; 53 as “non-bacterial” and 41 as “bacterial.” RNAseq and qPCR confirmed significant differences in mean expression for 10 genes previously identified as discriminatory for bacterial LRTI.”
“Our genes react differently to a virus than they do to bacteria,” remarked co-senior study investigator Thomas Mariani, Ph.D., professor of pediatrics and biomedical genetics at URMC. “Rather than trying to detect the specific organism that’s making an individual sick, we’re using genetic data to help us determine what’s affecting the patient and when an antibiotic is appropriate or not.”
