Investigation of NDM, VIM, KPC and OXA-48 genes, blue-carba and CIM in carbapenem resistant Enterobacterales isolates

INTRODUCTION

Carbapenem resistance is an emerging problem in Enterobactarales. We aimed to investigate the presence of carbapenemase genes blaNDM, blaKPC, blaVIM and blaOXA-48 and evaluate the phenotypic blue-carba method and carbapenem inactivation method (CIM) in Enterobacterales isolates.

METHODOLOGY

Total of 153 Enterobacterales isolates were tested in the study. Presence of blaNDM, blaKPC, blaVIM and blaOXA-48 genes was investigated by polymerase chain reaction (PCR) method. Carbapenemase production of the isolates was also tested by blue-carba method and CIM.

RESULTS

The presence of blaOXA-48 gene was detected in 110 (71.4%) and blaNDM gene was detected in 2 (1.3%) of the Enterobacterales isolates by PCR method. None of the isolates were positive for blaKPC and blaVIM genes. The 121 (78.54%) of the isolates were found to be positive by blue-carba method and CIM. And 105 (68.18%) of the isolates were determined as positive by both PCR, blue-carba and CIM.

CONCLUSIONS

In our study, 112 (72.7%) of the Enterobacterales isolates were found to be positive for carbapenemase genes (blaoxa-48 and blaNDM), and 121 (78.57%) of different isolates were found to be positive for blue-carba and CIM. However, 105 (68.18%) of the carbapenem resistance isolates found to be positive for all three methods.

A unique case report of a high-pressure paint injection injury of the hand with associated carbapenemase resistant Pseudomonas aeruginosa infection

High pressure injection injuries to the hand should not be taken lightly as urgent surgical debridement is required to ensure favorable outcomes. Empiric antibiotic administration is recommended; however, few studies focus on the secondary infection risk associated with these high pressure injection injuries. We present a rare case of a patient presenting with carbapenem resistant Pseudomonas aeruginosa following a high pressure paint gun injury of the thumb. Urgent surgical debridement with administration of broad-spectrum antibiotic coverage for both gram-negative and gram-positive bacteria is recommended. The injection of foreign materials can cause extensive tissue damage and immunosuppression facilitating growth of opportunistic bacteria that are often rare in healthy adults. We advocate for obtaining cultures at initial debridement to optimize treatment in these unique and rare injection injuries. Concerns should be raised as carbapenem resistant bacteria become more prevalent in the community.

Detection of the Klebsiella pneumoniae carbapenemase (KPC) in K. pneumoniae Isolated from the Clinical Samples by the Phenotypic and Genotypic Methods

BACKGROUND AND OBJECTIVE

The production of carbapenemases especially Klebsiella pneumoniae carbapenemase (KPC) is the most important mechanism of enzymatic resistance in isolated Enterobacteriaceae such as K. pneumoniae . The purpose of this study was detected of the carbapenemase producer K. pneumoniae strains with phenotypic and genotypic methods.

METHOD

Out of 800 strains, 270 K. pneumoniae strains (33.7%), were obtained. Antibiotic susceptibility test was performed by disk diffusion method in accordance with CLSI guidelines. Carbapenem resistant strains were identified by the Modified Hodge Test based on CLSI instruction and PCR for surveying the presence of bla -KPC gene.

RESULTS

A total 270 K. pneumoniae strains were collected. Antibiotic susceptibility test results showed the highest and lowest resistance was related to piperacillin (60.6%) and carbapenems (14.6%) respectively. 80.5% (33 of 41) isolates were positive by MHT, but all of them (100%) were negative for amplification of the bla -KPC gene in the PCR method.

CONCLUSION

The MHT was an appropriate method for approving carbapenemase production. Moreover, a laboratory could accept the carbapenemase production with PCR method for the bla-KPC gene, which has the additional profit of validating which KPC is present.