Search

Rapid and accurate detection can help optimize patient treatment and improve infection control against nosocomial carbapenemase-producing organisms (CPO). In this study, a total of 217 routine clinical isolates (Enterobacterales and A. baumannii), including 178 CPOs and 39 non-CPOs, were tested to evaluate the performance of six phenotypic carbapenemase detection and classification assays, i.e., BD Phoenix CPO detect panel, Rapidec Carba-NP, O.K.N detection kit, and three carbapenem inactivation methods (CIMs; mCIM, eCIM, sCIM). The overall detection sensitivity and specificity were 98.78% (95.21–99.79%) and 79.49% (63.06–90.13%), respectively, for the BD phoenix CPO P/N test; 91.93% (86.30–95.45%) and 100% (88.83–100%), respectively, for the Rapidec Carba-NP; 98.06% (94.00–99.50%) and 97.44% (84.92–99.87%), respectively, for mCIM; and 96.89% (92.52–98.85%) and 94.87% (81.37–99.11%), respectively, for sCIM. The classification sensitivity and specificity for the BD phoenix CPO Ambler test, the O.K.N detection kit, and the mCIM and eCIM were 56.71% (48.75–64.34%) and 94.87% (81.37–99.11%), 99.28% (95.43–99.96%) and 100% (88.83–100%), and 92.90% (87.35–96.23%) and 97.44% (84.92–99.87%), respectively. All detection assays were reliable in detecting carbapenemase. However, the Rapidec Carba-NP and mCIM were insufficient in detecting OXA-48-like enzymes. The BD phoenix CPO detect panel had a strong ability to detect carbapenemase but failed to classify 48/59 (81.36%) KPC, 8/52 (15.38%) NDM, 8/22 (36.36%) OXA-23-like, and 6/11 (54.55%) dual enzymes. The O.K.N detection kit accurately detected and differentiated KPC, NDM, and OXA-48-like enzymes existing alone or in combination. The results of this study will support reliable laboratory work tools and promote therapeutic and infection control decisions.

In over eighty years, despite successive antibiotics discoveries, the rapid advent of multidrug resistance among bacterial pathogens has jolted our misapprehension of success over them. Resistance is spreading faster than the discovery of new antibiotics/antimicrobials. Therefore, the search for better antimicrobials/additives becomes prudent. A water-soluble curcumin derivative (Curaq) was synthesised, employing a Cu (I) catalysed 1, 3-cyclo addition reaction; it has been evaluated as a potential treatment for multidrug-resistant isolates and as an antibiotic adjuvant for meropenem against hypervirulent multidrug-resistant Klebsiella pneumoniae isolates. We also investigated its solubility and effect over carbapenemase activity. Additionally, we investigated its impact on the AcrAB-TolC system. We found that Curaq inhibited bacterial growth at a minimal concentration of 16 µg/mL; at a 32 µg/mL concentration, it killed bacterial growth completely. Only nine (9.4%) Klebsiella isolates were sensitive to meropenem; however, after synergising with Curaq (8 µg/mL), 85 (88.54%) hvKP isolates became sensitive to the drug. The Curaq also inhibited the AcrAB-TolC efflux system at 1 µg/mL concentration by disrupting the membrane potential and causing depolarisation. The kinetic parameters obtained also indicated its promise as a carbapenemase inhibitor. These results suggest that Curaq can be an excellent drug candidate as a broad-spectrum antibacterial and anti-efflux agent.

Rapid and accurate detection can help optimize patient treatment and improve infection control against nosocomial carbapenemase-producing organisms (CPO). In this study, a total of 217 routine clinical isolates ( Enterobacterales and A. baumannii ), including 178 CPOs and 39 non-CPOs, were tested to evaluate the performance of six phenotypic carbapenemase detection and classification assays, i.e., BD Phoenix CPO detect panel, Rapidec Carba-NP, O.K.N detection kit, and three carbapenem inactivation methods (CIMs; mCIM, eCIM, sCIM). The overall detection sensitivity and specificity were 98.78% (95.21-99.79%) and 79.49% (63.06-90.13%), respectively, for the BD phoenix CPO P/N test; 91.93% (86.30-95.45%) and 100% (88.83-100%), respectively, for the Rapidec Carba-NP; 98.06% (94.00-99.50%) and 97.44% (84.92-99.87%), respectively, for mCIM; and 96.89% (92.52-98.85%) and 94.87% (81.37-99.11%), respectively, for sCIM. The classification sensitivity and specificity for the BD phoenix CPO Ambler test, the O.K.N detection kit, and the mCIM and eCIM were 56.71% (48.75-64.34%) and 94.87% (81.37-99.11%), 99.28% (95.43-99.96%) and 100% (88.83-100%), and 92.90% (87.35-96.23%) and 97.44% (84.92-99.87%), respectively. All detection assays were reliable in detecting carbapenemase. However, the Rapidec Carba-NP and mCIM were insufficient in detecting OXA-48-like enzymes. The BD phoenix CPO detect panel had a strong ability to detect carbapenemase but failed to classify 48/59 (81.36%) KPC, 8/52 (15.38%) NDM, 8/22 (36.36%) OXA-23-like, and 6/11 (54.55%) dual enzymes. The O.K.N detection kit accurately detected and differentiated KPC, NDM, and OXA-48-like enzymes existing alone or in combination. The results of this study will support reliable laboratory work tools and promote therapeutic and infection control decisions.

In over eighty years, despite successive antibiotics discoveries, the rapid advent of multidrug resistance among bacterial pathogens has jolted our misapprehension of success over them. Resistance is spreading faster than the discovery of new antibiotics/antimicrobials. Therefore, the search for better antimicrobials/additives becomes prudent. A water-soluble curcumin derivative (Cur aq ) was synthesised, employing a Cu (I) catalysed 1, 3-cyclo addition reaction; it has been evaluated as a potential treatment for multidrug-resistant isolates and as an antibiotic adjuvant for meropenem against hypervirulent multidrug-resistant Klebsiella pneumoniae isolates. We also investigated its solubility and effect over carbapenemase activity. Additionally, we investigated its impact on the AcrAB-TolC system. We found that Cur aq inhibited bacterial growth at a minimal concentration of 16 µg/mL; at a 32 µg/mL concentration, it killed bacterial growth completely. Only nine (9.4%) Klebsiella isolates were sensitive to meropenem; however, after synergising with Cur aq (8 µg/mL), 85 (88.54%) hvKP isolates became sensitive to the drug. The Cur aq also inhibited the AcrAB-TolC efflux system at 1 µg/mL concentration by disrupting the membrane potential and causing depolarisation. The kinetic parameters obtained also indicated its promise as a carbapenemase inhibitor. These results suggest that Cur aq can be an excellent drug candidate as a broad-spectrum antibacterial and anti-efflux agent.

The emergence of bla KPC-2 and bla NDM-1 producing Klebsiella pneumoniae represents a great problem in many Egyptian hospitals. One hundred and twenty-six K . pneumoniae (CPKP) was detected by the modified carbapenem inactivation method (mCIM), the EDTA-modified carbapenem inactivation method (eCIM), and an E-test. Based on the polymerase chain reaction, all isolates were negative for K . pneumoniae (CPKP) was detected by the modified carbapenem inactivation method (mCIM), the EDTA-modified carbapenem inactivation method (eCIM), and an E-test. Based on the polymerase chain reaction, all isolates were negative for bla- VIM-1 and bla- IMP-1 , fifteen of these isolates were positive for both bla KPC-2 and bla NDM-1 , two isolates were positive for bla KPC-2 only, and twenty-eight isolates were positive for bla- NDM-1 only. Although one isolate was positive for the string test, all CPKP isolates were negative for capsular genes. Only 71.1% of CPKP transferred their plasmids to their corresponding transconjugants ( E. coli J53). The resistance patterns of the clinical isolates and their transconjugates were similar, except for 12 isolates, which showed differences with their transconjugates in the resistance profile of four antibiotics. Molecular typing of the plasmids based on replicon typing showed that Inc FIIK and FII plasmids predominated in isolates and their transconjugants carrying bla KPC-2 and/or bla NDM-1 . Conjugative Inc FII plasmids play an important role in the spread of CPKP, and their recognition is essential to limit their spread., Competing Interests: The authors declare no conflict of interest.