Performance of rapid tests for carbapenemase detection among Brazilian Enterobacteriaceae isolates

Abstract

The global emergence of carbapenemases led to the need of developing new methods for their rapid detection. The aim of this study was to evaluate the performance of the rapid tests for carbapenemase-producing and non-producing Enterobacteriaceae. Carbapenem non-susceptible Enterobacteriaceae from a surveillance study submitted to a multiplex real time PCR for carbapenemase detection were included in this study. The isolates were subjected to the rapid phenotypic tests Carba NP, Blue-Carba and Carbapenem Inactivation Method (CIM). A total of 83 carbapenemase-producing (43) and non-producing (40) isolates were included in the study. The sensitivity/specificity were 62.7%/97.5%, 95.3%/100%, and 74.4%/97.5% for Carba NP, Blue-Carba and CIM, respectively. Both Carba NP and Blue-Carba presented their final results after 75 min of incubation; the final results for CIM were obtained only after 8 h. Failure to detect OXA-370 carbapenemase was the main problem for Carba NP and CIM assays. As the Blue-Carba presented the highest sensitivity, it can be considered the best screening test. Conversely, CIM might be the easiest to perform, as it does not require special reagents. The early detection of carbapenemases aids to establish infection control measures and prevent carbapenemases to spread reducing the risk of healthcare associated infections and therapeutic failure.

Diagnostic Accuracy of Carba NP test for Rapid Detection of Carbapenemase-Producing Enterobacteriaceae: Systematic Review and Meta-Analysis

“…The present meta-analysis showed that the sensitivity and specificity of Carba NP test were 0.96 and 1.00, respectively, the AUC was 1.00, and the mean DOR was 573.46 indicating a high level of overall accuracy. We also noted that one study [9] showed low sensitivity (0.63), and one study 10 demonstrated a low specificity (0.71) when they used Carba NP test for the rapid detection of carbapenemase production.…”

“…Our primary searches identified 1405 articles, and from these studies, eighteen articles [8][9][10][11][19][20][21][22][23][24][25][26][27][28][29][30][31][32] met eligibility criteria and are accepted in this study. The main reasons for exclusion are : did not include original data, a reference test other than PCR was used, and the study was not reported in English.…”

“…Carba NP test is a biochemical method were suggested to tackle this challenge 8 , this test depends on the direct detection of Carbapenemase-producing bacteria by Carbapenem hydrolysis, it is applied successfully for Enterobacteriaceae [9][10][11] , Pseudomonas aeruginosa and Acinetobacter baumannii [12][13][14][15] . Carba NP test can detect all classes of carbapenemase (without distinction) in less than two hours, making it a rapid test for the detection of CPE 8 .…”

Emergence of OXA-10 and OXA-48 like carbapenemases among Enterobacter isolates from inpatients in southern Iran

“…The mCIM is a reliable and simple method and has a sensitivity of 98-100% in comparison with the modi ed Hodge test and the carbapenemase Nordmann-Poirel (carba NP) test with sensitivities of 93-98% and 73-100%, respectively. Furthermore, due to being expensive of PCR, mCIM could be a suitable alternative method for detecting of carbapenemase producers [12,[31][32][33].…”

“…On the other hand, we identi ed the presence of class 1, 2 and 3 integrons among our isolates. Carbapenemase genes are harbored on mobile genetic elements and can be disseminated to other bacteria, therefore contributing to the origin of antimicrobial resistance among Enterobacteriaceae members [32]. It is reported that class 1 integron is found in 40-70% of Gram-negative pathogens and has had a major role in widespread of antibiotic resistance [14,15].…”