Detection of carbapenemase-resistant Enterobacterales in blood culture in 15 minutes

Background: Bacteremia leading to sepsis and organ dysfunction is a life-threatening situation. One major challenge in treatment of sepsis is the uprising prevalence of antibiotic resistant bacteria, such as Carbapenem-resistant Enterobacterales (CRE). In recent years several molecular assays have been developed for the detection of CRE mechanisms, enabling rapid results reporting. We evaluated the performance of NG-Test CARBA 5 (NG Biotech) kit for detection of CRE, directly from patients’ blood culture. Methods: Carbapenemase-producing (CP) CRE-positive isolates (n=38) and non-carbapenemase CRE (non-CP) isolates (n=10), previously identified using the routine methods practiced at the clinical microbiology laboratory of the Baruch Padeh Medical Center, Israel were used in this analysis. Variable concentrations of the bacterial isolates were added to a suspension composed of blood unit and saline simulating the composition of a blood culture. Samples were then transferred to an anaerobic blood culture bottle and later tested it with the NG-Test CARBA 5 (NG Biotech) kit, that identifies the CRE mechanism in 15 minutes. Results: The NG-Test CARBA 5 kit correctly identified 43 samples (89.5%). The sensitivity and specificity of the kit were 86.8% and 100%, respectively. Conclusions: The NG-Test CARBA 5 kit is a reliable and accessible tool for the rapid diagnosis of CRE bloodstream infections.