Biofilm Microbiome and Microbial DNA Load in Neonatal Catheter-associated Bloodstream Infections

Catheter-associated bloodstream infections (CLABSIs) are a significant component of healthcare-associated infections (HAI),which are associated with significant mortality, morbidity and healthcare costs. Neonates are at higher risk for CLABSIs than children or adults and CLABSIs are seen more commonly in neonatal than pediatric or adult intensive care units. Neonates, who develop CLABSIs, are not only at serious risk for mortality but also long term neurodevelopmental impairment. CLABSIs are often caused by organisms colonizing the skin and the most frequently isolated organisms are CONS, S. aureus and Candida.

The catheter biofilm microbiome, to our knowledge has not been investigated before. Evaluation of biofilm microbial signatures and microbial DNA load is a novel strategy that may permit earlier diagnosis of CLABSIs. Earlier detection may enable earlier targeted therapy such as antimicrobial lock solutions and may facilitate preservation of catheters in this vulnerable population. Catheter microbial DNA signatures or load may be useful biomarkers to not only predict or diagnose infections but to monitor antibiotic therapy and to confirm resolution of infection.

We will study 15 percutaneously inserted central catheters (PICC) each from neonates with CLABSIs and those without. We will evaluate the bacterial microbiome by profiling V3-5 region of the 16S rDNA, by PCR and pyrosequencing. We will correlate the catheter biofilm microbiome with catheter tip cultures and the skin microbiome at the catheter entry site. We aim to identify microbial signatures that predispose to dissemination of infection from catheter biofilms leading to CLABSIs. Further, we will quantify microbial DNA load in blood from the catheters at the time of removal, by real-time PCR of the bacterial 16S rDNA.