Bacteremia leading to sepsis and organ dysfunction is a life-threatening situation, leading to death of up to one fourth of the infected individuals around the world. One major challenge in the treatment of sepsis is the rising 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 the NG-Test CARBA 5 (NG Biotech) kit in detection of CRE in simulated blood cultures. Carbapenemase-producing (CP) CRE 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 human blood and saline, simulating the composition of a blood culture. Samples were then transferred to an anaerobic blood culture bottle and later tested with the NG-Test CARBA 5 (NG Biotech) kit, that identifies the CRE mechanism within 15 minutes. The NG-Test CARBA 5 kit correctly identified 43 samples (89.5%). The sensitivity and specificity of the kits were 86.8% and 100%, respectively. In conclusion, the NG-Test CARBA 5 kit is a reliable and accessible tool for the rapid diagnosis of CRE bloodstream infections.

Objective We evaluated NG-Test CARBA 5, a new phenotypic carbapenemase detection assay, and compared it to the routine Xpert CARBA-R polymerase chain reaction assay. Furthermore, we tested the kit’s performance after bacterial growth on 4 different solid media. Methods Seventy carbapenem resistant Enterobacteriaceae (CRE) isolates (60 were carbapenemase producers) were collected at the Poriya Baruch Padeh Medical Center. All isolates were grown on 4 types of agar media—BD BBL CHROMagar carbapenem resistant Enterobacteriaceae, BD CHROMagar Orientation, BD MacConkey II agar, and BD Trypticase Soy Agar II with 5% sheep blood—and were then subjected to NG-Test CARBA 5 kit analysis. Results The NG-Test CARBA 5 specificity was 100% for all 4 media. However, the sensitivity was higher when bacteria were grown on TSA with 5% sheep blood (98.3%) as compared with the Orientation medium (88.3%), the CPE medium (84.7%), and the MacConkey medium (83.6%). In addition, some of the carbapenemase mechanisms such as Verona Integron-Mediated Metallo-β-lactamase were detected with low agreement levels in specific media but higher agreement levels in the other media. Conclusion NG-Test CARBA 5 may enable faster detection of carbapenemase producing CRE, which will be of value for treatment adjustment and prevention control. However, the medium type on which the bacteria are grown affects kit sensitivity.

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.