Evaluation of Combined Use of Temocillin Disk and Mastdisks Inhibitor Combination Set Against Polymerase Chain Reaction for Detection of Carbapenem-Resistant Enterobacteriaceae

Abstract

AIM:To evaluate the diagnostic performance of MDI and temocillin disk (30 μg) for detection of carbapenem-resistant Enterobacteriaceae in comparison to real-time PCR.MATERIAL AND METHODS:Fifty specimens submitted to the Microbiology Laboratory of Ain Shams University Hospitals and showed resistance to carbapenem drugs through routine culture and susceptibility testing, were assessed by both temocillin disk (30 μg) and MDI set to detect carbapenem-resistant Enterobacteriaceae. Results were compared to real-time PCR for detection of carbapenemase genes blaKPC, blaNDM, blaOXA–48-like, blaVIM, and blaIMP.RESULTS:Our work revealed that most of the CPE isolates were Klebsiella species (62%) followed by E. coli (24%), Serratia (10%) and Citrobacter (4%). Phenotypic detection of carbapenem-resistant classes revealed OXA - 48 in 96% of isolates, followed by MBLs (82%), and KPC (34%). All isolates were negative for AmpC. Detection of the genes by real-time PCR showed that the predominance was for the blaOXA-48 gene (96%) then blaVIM (94%) followed by blaNDM (54%), blaKPC (46%) and finally blaIMP (40%). Evaluation of the MDI set against PCR showed sensitivity (82.1%) and specificity (70%). The temocillin disk had 97.9% sensitivity and 50% specificity. The evaluation of Temocillin disk and MDI in combination for detection of carbapenem-resistant Enterobacteriaceae showed 99.7% sensitivity and 35% specificity.CONCLUSION:Adding Temocillin disk to Mastdisks ID inhibitor combination set provides a simple, easy, rapid and highly sensitive test that can be used for screening and classification of carbapenem-resistant Enterobacteriaceae. However, it still needs confirmation by molecular techniques.

Comparison of Chromogenic Culture Media, Rapid Immunochromatographic Test and Temocillin Resistance for The Detection of OXA-48 Carbapenemase-Positive Klebsiella Pneumonia Strains

“…When they assessed for diagnostic accuracy, they reported a very low PPV (%27.6) with high NPV (%99.5) for diagnostic capability. Another study, by Shaker et al revealed in 48 OXA-48-positive CPE isolates that 30 µg temocillin disc had 97.9% sensitivity, 50% specificity, 97.95% PPV and 50% NPV for detecting OXA-48 production [18]. We demonstrated that temocillin disk diffusion method had a sensitivity of 100% and a specificity of 77.8% in detecting the presence of OXA-48.…”

Prevalence and characterisation of carbapenemase encoding genes in multidrug-resistant Gram-negative bacilli

“…This problem is one of the main reasons for the expression of carbapenemase genes among members of this family [ 7 ]. Carbapenemase enzymes are the most common mechanism by which resistance to carbapenems arises [ 8 , 9 ]. Carbapenem resistance has been labelled in Enterobacteriaceae , mostly in Klebsiella pneumoniae compared to Escherichia coli or other Enterobacterial species, and in non-fermentative Gram-negative bacilli such as Pseudomonas aeruginosa and Acinetobacter baumannii [ 4 ].…”

“…Initially, carbapenemases were chromosomally mediated in a few specific species, but now they mediate a plasmid, or both a chromosomal and a plasmid. This results in a more violent spread of resistance due to horizontal transfer between different bacterial species and genera [ 9 ]. Since 1993, different types of carbapenemases have been recognised belonging to three molecular classes, the Ambler classes A, B and D beta-lactamases [ 14 ]: class A carbapenemases, Klebsiella pneumoniae carbapenemase (KPC) enzymes; class B metallo-beta-lactamases (MBLs) such as New Delhi metallo-beta-lactamases (NDM), Verona integron-encoded metallo-beta-lactamase (VIM) and imipenemase (IMP) type enzymes; and class D carbapenem-hydrolysing oxacillinase (OXA) such as OXA-48 enzymes [ 15 ].…”

“…The OXA-48 enzyme shows low activity against carbapenems, high activity against penicillin but only low activity against 3rd and 4th generation cephalosporins. However, this is rarely a treatment option because other beta-lactamases, such as ESBL, are often associated [ 9 ]. Globally, most common carbapenemases consist of MBLs (IMP, VIM and NDM), OXA and KPC.…”

Clonal Dissemination of KPC-2, VIM-1, OXA-48-Producing Klebsiella pneumoniae ST147 in Katowice, Poland

“…According to the protocol, the boronic acid combined-disk tests using meropenem (10 μg) as the antibiotic substrate and 3-aminophenylboronic acid (3-APBA) (300 g, Sigma-Aldrich) as the inhibitor of KPC production was used. The detection of OXA-48 was performed in line with the EUCAST guidelines ( Shaker et al 2018 ). MDR and XDR were defined according to a standardized international document ( Magiorakos et al 2012 ).…”