Detection Of Carbapenem Resistance Research Articles

Detection of Carbapenem Resistance Using the Genotypic and Phenotypic Methods in Klebsiella pneumoniae

Aim: This study aimed to detect the carbapenem resistance of the Klebsiella pneumoniae strains, isolated from clinical specimens with genotypic and phenotypic methods. Material and Methods: A total of 87 Klebsiella pneumoniae strains whose carbapenem resistance was determined by disc diffusion method were included in the study. Carbapenemase was investigated using the combined disk method and polymerase chain reaction (PCR). Results: The evaluation of the PCR results demonstrated that OXA was detected in 60 (68.9%) samples, NDM was detected in 20 (22.9%), OXA + NDM in 5 (5.7%), and KPC was detected in 1 (1.1%) out of 87 clinical samples. Carbapenemase was not detected in one specimen with the PCR method. The results were found compatible with the combined disc test results for all isolates which were detected as only OXA, NDM, and KPC type carbapenemase positive. In 5 (5.7%) strains in which the co-existence of NDM and OXA type carbapenemases was detected by PCR, the combined disc method detected only OXA type carbapenemase. Conclusion: The combined disk method is inadequate in the presence of strains that have multiple carbapenemases, and also have OXA which is the most frequently detected carbapenemase in our hospital. EUCAST recommends verification by other methods in the presence of OXA-48. Genotypic methods can be used for confirmation testing. The detections of strains with NDM, multiple carbapenemases, and the first detection of KPC were striking in the study. Monitoring the spread of these strains in the hospital will be necessary for infection control.

Detection of Carbapenem Resistance among Enterobacteriaceae Pathogens Isolated from Clinical Samples in Shendi locality

Introduction: The majority of antimicrobial agents are ineffective against carbapenem-resistant Enterobacteriaceae (CRE) infections, leading to unfavorable clinical consequences. This fact is associated with higher mortality and morbidity rates, prolonged hospital stays, and increased treatment-related costs. Carbapenems are the last line for the treatment of infection caused by bacteria resistance to a broad spectrum of antibiotics. Objective: This study aimed to detect the Distribution of Carbepanems Resistance in Enterobacteriaceae Pathogens Isolated from Clinical Samples in the Shendi locality. Methods: A cross-sectional study and a laboratory-based study were carried out on 63 isolates from different specimens, 63 types of pathogenic bacteria were isolated and identified using Gram stain, biochemical reactions, and testing for their susceptibility to Carbapenems antibiotics was performed for all Enterobacteriaceae isolates. Result: The isolated Enterobacteriaceae comprising of 19.0(30.2%) E.coli, 17 (27.0%) K. pneumoniae, 13(20.6%) P. vulgaris, 5(7.9%) P. mirabilis, 1(1.6%) Enterobacter species, 3(4.8%) C. freundii and 5(7.9%) M. morganii. Carbapenem (Imipenem and meropenem) susceptibility testing showed that 36.0% of Enterobacteriaceae isolates were Carbapenem-resistant. Conclusions: The study revealed the low resistance pattern of Enterobacteriaceae to Carbapenems. Despite that E.coli (19.0, 30.0%) was the most isolated organism, and K. pneumonia (7.0, 11.0%) was the most resistant isolate to Carbapenems. The urine sample had the highest degree of resistance. There was a correlation between patients with chronic diseases such as cancer and the resistance level to Carbapenems, while there was no statistical significance between the period of antibiotics usage and the degree of resistance.

Detection of Carbapenem-resistance in CRE by Comparative Assessment of RAPIDEC® CARBA NP and Xpert™Carba-R Assay.

Carbapenem-resistant Enterobacteriaceae (CRE) infections resist nearly most available antimicrobials, resulting in poor clinical outcomes. Saudi Arabia has a relatively high CRE prevalence. This study aims to evaluate the sensitivity of Rapidec Carba NP test and GeneXpert Carba-R assay compared with conventional manners for detection of carbapenemase-producing Enterobacteriaceae. This is a cross-sectional study including a total of 90 CRE isolates examined at two tertiary hospitals in KSA from October 2020 to December 2021. Gram-negative Enterobacteriaceae were identified by using Vitek 2 system and were furtherly tested for imipenem and meropenem susceptibility by E- test strips, followed by Rapidec Carba NP test and the Xpert™Carba-R assay. Carbapenem-resistant K. pneumoniae (78.9%) and carbapenem-resistant E. coli (14.4%) were the two most common isolates species. Colistin (98.9%) and tigecycline (88.9%) were the most effective antibiotics against CRE isolates, followed by amikacin (52.2%), gentamicin (33.3%), cotrimoxazole (15.6%), and ciprofloxacin (8.9%). blaOXA-48 was the predominant carbapenemase gene (44.4%), followed by blaNDM (32.2%). blaKPC gene was not detected. The Rapidec Carba NP and the Xpert™Carba-R demonstrated an overall sensitivity of 69.3% and 88%, respectively, in comparison to gold standard detection of meropenem and imipenem resistance by Vitek 2 system and E- test strips. RAPIDEC® CARBA NP may be a beneficial screening test for detecting CRE, but for confirmation of the results, Xpert Carba-R assay is more sensitive, significantly lowering the turnaround time compared to reference traditional methods. The information on carbapenemase genes may be used for epidemiologic purposes and outbreak management.

First detection of carbapenem resistance in Enterobacteriaceae isolates isolated from dairy cows’ mastitis infection in Türkiye

With this study, carbapenem resistance genes were declared for the first time in Enterobacteriaceae isolates isolated from dairy cows’ mastitis infection in Türkiye. In the bacteriological examination of 212 milk samples, 14 (6.60%) E. coli, three (1.41%) Klebsiella oxytoca, and two (0.94%) Klebsiella pneumonia were isolated. At least two E. coli isolates were found to be resistant to all of the antibiotics used in the antibiogram test. The highest resistance was found against cefotaxime and amoxicillin in K. oxytoca isolates. According to the results of PCR targeting blaCTX-M, blaTEM, and blaSHV genes, the blaCTX-M gene was detected in one K. oxytoca and four E. coli isolates, which were found ESBL positive. According to the results of PCR targeting carbapenem and colistin resistance genes, the IMP gene was detected in four E.coli, one K. oxytoca, and one K. pneumonia isolates. OXA-48-like gene was detected in two E. coli isolates. This two E. coli isolates were also IMP gene positive. While NDM gene was detected in two E. coli, KPC gene was detected in one E. coli isolate. One of the colistin resistance genes, mcr-1 was detected in two E.coli strains with PCR. This study showed that ESBL production and carbapenem resistance in Enterobacteriaceae family strains to become prevalent and increasing, especially among E. coli isolates. Furthermore, identification of multiple antibiotic resistance in the isolates indicated that antibiotic resistance also spread rapidly and increased.

Molecular Detection of OXA-type Carbapenemases among Acinetobacter baumannii Isolated from Burn Patients and Hospital Environments

Background:Acinetobacter baumanniiis known as one of the major causes of nosocomial infections, especially in intensive care units and burn patients. The emergence of antimicrobial resistance in burn wound bacterial pathogens is a severe health crisis. Detection of carbapenem resistance and genetic elements inA. baumanniiassociated with burn patients and hospital environments play a key role in the control and alerting in clinical settings.Purpose:In this study, the prevalence of OXA-type carbapenemases was investigated inA. baumanniistrains isolated from burn patients and from a hospital environment in Tehran, 2021.Methods:A total of 85 non-duplicateA. baumanniiisolates (53 from various surfaces of the hospital environment and 32 from burn patients) were recovered in the Burns Hospital in Tehran. TheA. baumanniiisolates were screened for antibiotic susceptibility and the presence of the most common OXA-type carbapenemase genes.Results:A. baumanniiwas isolated from 38.5% of hospital patient burn wounds and 22.1% of surfaces, including burn units (15.6%) and intensive care units (52.4%). Antibiotic susceptibility results showed that (100%) of burn patient isolates were resistant to imipenem, while (100%) of ICU isolates and (96.8%) of burn isolates were resistant to imipenem. All clinical isolates were identified as MDR and XDR, whereas all (100%) and 98.1% of environmental isolates were identified as MDR and XDR, respectively. All studiedA. baumanniiisolates carriedblaOXA-51-likegene. Moreover, 50 (94.3%) and 49 (92.5%) of environmental isolates, 32 (100%) and 30 (93.7%) of burn patient isolate harboredblaOXA-23-likeandblaOXA-24/40–likegenes, respectively. None of the isolates carried theblaOXA-58orblaOXA-143genes and all isolates had at least 2 OXA-type carbapenemase genes.Conclusion:Our results suggest that surfaces in the hospital environment, particularly in ICUs, are contaminated with MDR or XDRA. baumanniistrains. They may be considered a potential reservoir for the colonization of hospital patients. In addition, OXA-type carbapenemases, including OXA-23-like and OXA-24/40-like, appear to be one of the major mechanisms of carbapenem resistance in the clinical and environmentalA. baumanniistrains.

Detection of carbapenem resistance among Escherichia Coli and Klebsiella Pneumoniae in Chest intensive care unit at Assiut University Hospitals,Egypt.

Detection of carbapenem resistance among Escherichia Coli and Klebsiella Pneumoniae in Chest intensive care unit at Assiut University Hospitals,Egypt.

Detection of Carbapenem Resistance of Proteus mirabilis Strains Isolated from Foxes, Raccoons and Minks in China.

Simple SummaryProteus is found abundantly in soil and water, and it has been known to cause human urinary tract infections and food poisoning. Currently, the opportunistic pathogen Proteus mirabilis (P. mirabilis) is also found to be an emerging threat to animals, such as birds, fish, dogs, etc. In this study, we examined the antibiotic resistance genes and virulence genes of P. mirabilis isolates from raccoons, foxes and minks. Among a total of 53 P. mirabilis isolates, the proportion of bacteria resistant to three or more antibiotic classes was up to 73.58%, and the detection rate of carbapenem-resistant P. mirabilis isolates was up to 71.7%, putting human health at risk. The close evolutionary relationship between P. mirabilis isolates from animals and the farm environment suggested that multidrug-resistant P. mirabilis from animals could pose a great environmental threat. In addition, the carriage rate of virulence-associated genes was not positively correlated with P. mirabilis pathogenicity in a Galleria mellonella model, highlighting the importance of further understanding the virulence of P. mirabilis in future studies.Proteus mirabilis, an opportunistic pathogen, is found to be an emerging threat to both animals and humans for a variety of infections. However, the characteristics of P. mirabilis infections from foxes, raccoons and minks remain unclear. In this context, we identified the antibiotic resistance genes and virulence genes of P. mirabilis isolates from foxes, raccoons and minks in China. Most isolates showed resistance to florfenicol (90.57%), trimethoprim-sulfamethoxazole (73.58%), and imipenem (71.70%). A total of 73.58% of isolates were resistant to antibiotics from at least three or more classes, and were categorized as multi-drug resistant. A total of 33.33% of the isolates were resistant to antibiotics from seven classes. The most prevalent resistant were sul1 (94.34%), followed by floR, blaTEM, aac(6′)Ib-cr and blaOXA-1 with the detection rate of 88.68%, 83.02%, 71.70% and 60.38%, respectively. Among the 51 P. mirabilis isolates that were resistant to beta-lactam antibiotics, all isolates carried at least one beta-lactam gene. In addition, blaNDM and blaOXA-24 genes were firstly reported in carbapenem-resistant P. mirabilis isolates from foxes, raccoons and minks. All isolates exhibited the virulence genes ureC, zapA, pmfA, atfA and mrpA. P. mirabilis isolates carrying all detected 10 virulence genes from different animal species showed different lethal abilities in a G. mellonella larvae model. More importantly, the profiles of antibiotic resistance genes of isolates from fur animals and the environment were generally similar, and phylogenetic analysis showed that the P. mirabilis isolates from farm environment samples may have close relatedness with that from animals.

Development of Loop-Mediated Isothermal Amplification Rapid Diagnostic Assays for the Detection of Klebsiella pneumoniae and Carbapenemase Genes in Clinical Samples.

Klebsiella pneumoniae is an important pathogenic bacterium commonly associated with human healthcare and community-acquired infections. In recent years, K. pneumoniae has become a significant threat to global public and veterinary health, because of its high rates of antimicrobial resistance (AMR). Early diagnosis of K. pneumoniae infection and detection of any associated AMR would help to accelerate directed therapy and reduce the risk of the emergence of multidrug-resistant isolates. In this study, we identified three target genes (yhaI, epsL, and xcpW) common to K. pneumoniae isolates from both China and Europe and designed loop-mediated isothermal amplification (LAMP) assays for the detection of K. pneumoniae in clinical samples. We also designed LAMP assays for the detection of five AMR genes commonly associated with K. pneumoniae. The LAMP assays were validated on a total of 319 type reference strains and clinical isolates of diverse genetic backgrounds, in addition to 40 clinical human sputum samples, and were shown to be reliable, highly specific, and sensitive. For the K. pneumoniae–specific LAMP assay, the calculated sensitivity, specificity, and positive and negative predictive values (comparison with culture and matrix-assisted laser desorption/ionization–time of flight mass spectrometry) were all 100% on clinical isolates and, respectively, of 100%, 91%, and 90%, and 100% when tested on clinical sputum samples, while being significantly faster than the reference methods. For the bla KPC and other carbapenemases’ LAMP assays, the concordance between the LAMP results and the references methods (susceptibility tests) was 100%, on both pure cultures (n = 125) and clinical samples (n = 18). In conclusion, we developed highly sensitive and specific LAMP assays for the clinical identification of K. pneumoniae and detection of carbapenem resistance.

Detection of Carbapenem resistance by Carbapenemin activation method in tertiary care centre in central Kerala

Detection of Carbapenem resistance by Carbapenemin activation method in tertiary care centre in central Kerala

Detection of carbapenem resistance and virulence genes among Acinetobacter baumannii isolated from hospital environments in center of Iran

Carbapenem-resistant Acinetobacter baumannii are the top urgent antibiotic resistance threat in the world. The aims of this study were the determination of carbapenem-resistant genes and virulence genes among isolates from hospital environments. In this study, A. baumannii isolated from hospital environments and evaluated its antibiotic resistance, virulence factors, and resistance genes. Of 258 samples, 58 showed growth of the target organism. Antibiotic susceptibility test results considered all the A. baumannii to be multidrug-resistant isolates with the highest resistance being 36.2% to ciprofloxacin; while the most effective antibiotics with 98.3% susceptibility was piperacillin-tazobactam. Of these 58 hospital environment isolates, 18 isolates were positive for Metallo beta-lactamase. Overall, 65% of the isolates from hospital environments had many virulence factors. PCR assays demonstrated the highest and lowest positive results in csgA and cvaC gene among hospital environment isolates. Results indicate that the determination of carbapenem-resistant genes and virulence genes among isolates from hospital environments is very important.

Performance of the BD Phoenix CPO detect assay for detection and classification of carbapenemase-producing organisms

Increasing worldwide, prevalence of carbapenem-resistant gram-negative bacteria demands urgent a need for rapid detection and accurate identification of carbapenemases. The BD Phoenix CPO detect (PCD) assay possesses an in-built capacity for parallel susceptibility testing and detection of carbapenemases. Here, the ability of the assay to detect and classify carbapenemase production was tested in a collection of carbapenem-resistant Enterobacterales and non-fermentative gram-negative rods. The ability of the PCD assay to detect and classify carbapenemases was investigated in a collection of 194 clinical, carbapenem-resistant isolates (Enterobacterales [n = 65]; non-fermentative gram-negative rods [n = 129]). AST results were compared to MICS determined by gradient diffusion to determine accuracy of the PCD assay. The accuracy of the PCD assay to detect carbapenemases was compared to the results of molecular isolate characterization using a LDT multiplex carbapenemase PCR assay. All 194 isolates classified as carbapenem-resistant by reference susceptibility testing were also classified correctly as CRO by the PCD assay. Performance analysis of the PCD assay to detect carbapenemase production revealed an overall sensitivity of 98.29% and specificity of 17.95% for the detection of carbapenemase production. For the classification of carbapenemases classes A, B, and D, the PCD correctly classified 79.17% Enterobacterales and 67.16% non-fermentative gram-negative rods. The PCD assay is a reliable tool for the detection of carbapenem resistance and allows for parallel analysis of carbapenemase production. However, while sensitivity is high, low specificity in carbapenemase detection and erroneous classification demands mandatory confirmation by alternative methods, especially in non-fermentative gram-negative bacteria.

Detection of Carbapenem resistance among Escherichia coli and Klebsiella pneumoniae isolates in a tertiary care hospital in South India

Introduction: Carbapenems are a class of ?lactam antibiotics with a broad spectrum of activity and greatest potency against Gram positive and Gram negative bacteria and their use has markedly increased in the past few decades. The development of carbapenem resistance has now become a grave concern in the treatment of diseases.Materials and Methods: The study was a laboratory based cross sectional study done with the main aim to detect the presence of carbapenem resistance among E. coli and K. pneumoniae isolates. A total of 550 samples (pus, urine, sputum, etc) were subjected to culture. The antibiotic susceptibility for various antibiotics was studied by Kirby Bauers Disk Diffusion Test. Carbapenem resistance and Metallo-betalacatamase (MBL) production was detected using Modified Hodge Test and EDTA Disk Synergy Test respectively.Result: A total of 129 isolates (43%) were meropenem resistant out of which 42 isolates (14%) were MBL producing. Carbapenase production was noted in 42.1% of E.coliand45.8% of K. pneumoniae. Twelve percent of the E. coli and 20.8% of the K. pneumoniae were found to have prevalence of MBL producers respectively.Conclusion: High incidence of carbapenem resistance and MBL producers was noted in the isolates. Given the emerging pattern of resistance to these third line antimicrobials and limited new molecules it is imperative to frame a new antibiotic policy and its strict implementation.

A Comparative Study between Different Laboratory Tests for Detection of Carbapenem Resistance in Klebsiella Pneumoniae

Background : Klebsiella pneumoniae is among the most common gram-negative bacteria encountered by physicians worldwide. It is a common hospital-acquired pathogen, causing urinary tract infections, nosocomial pneumonia, and intra abdominal infections. K. pneumoniae is also a potential community-acquired pathogen. Objectives : were to determine carbapenem resistance among Klebsiella pneumonia isolates by routine disc diffusion test and E test, determine carbapenemase production by modified Hodge test and to study the presence of bla KPC gene in carbapenem-resistant and carbapenem sensitive Klebsiella  pneumoniae isolates. Methodology : Fifty klebsiella pnumoniae isolates were identified and subjected to antimicrobial susceptibility testing by disk diffusion test against three carbapenem antibiotics (Imipenem, Ertapenem, and Meropenem) and were subjected to determination of minimum inhibitory concentration (MIC) to ertapenem using E-test.  Modified Hodge test was carried out for strains included in the study. Twenty-six K. pneumoniae isolates were subjected to PCR for detection of bla kpc gene. Thirteen confirmed carbapenem resistant isolates by disc diffusion, E-test and MHT and 13 confirmed carbapenem sensitive isolates by the same tests. Results: 13/50 (26%) isolates were resistant to both meropenem and ertapenem while only 11/50(22%) isolates were resistant to imipenem. Ertapenem sensitivity tests revealed that there was a discrepancy between the results of E test and disc diffusion method in two strains. The two strains were reported resistant by disc diffusion method and intermediate sensitive by E test. All carbapenem resistant strains 13 out of 50 strains showed positive modified Hodge test. The 26 isolates tested for bla kpc gene were negative. In conclusion resistance of K.pneumoniae to carbapenems was detected in 26% of isolates . The disc diffusion susceptibility did not report major errors in comparison to E test for ertapenem. Expression of carbapenemase was detected in all carbapenem resistant isolates by modified Hodge test while bla KPC gene was not detected among either carbapenem resistant or susceptible strains.

Detection of Carbapenem Resistance in Salmonella Species from a Tertiary Hospital in Eastern Cape, South Africa

Aims: Broad-spectrum carbapenem group is the current therapy for strains of Enterobacteriaceae that express extended spectrum beta-lactamases (ESBLs). However, recent reports of therapeutic failures of carbapenems with strains that produce multiple β-lactamases are being documented. This study profiled antibiotic resistance in clinical isolates of Salmonella species in a tertiary hospital in the Eastern Cape of South Africa with the aim of identifying the status of Salmonella therapy in the region. Study Design: This is an analytical study. Place and Duration of Study: Salmonella isolates (119) from 96 blood and 23 stool specimens of patients attending Nelson Mandela Academic Hospital Complex (NMAHC) and surrounding clinics,

Genotypic and phenotypic identification of aeromonas species and carbapenem resistance in Queensland, Australia

Aims This study defines the population of Aeromonas spp. in Queensland and carbapenem resistance due to carbapenemase production, CphA. Phenotypic tests were correlated with the presence of the cphA gene. Methods Isolates from blood (22), wound (46), sterile sites (11), stool (18), eye (2) and sputum (1) were characterised by rpoB and gyrB sequencing. Disc diffusion and meropenem E-test MIC were determined. Carbapenemase production was assessed by Carba NP test and cphA by PCR. Results Isolates identified as A. dhakensis (39), A. veronii (21), A. hydrophila (20), A. caviae (14), A. jandaei (4), A. bestiarum (1), and A. sanarellii (1). Disc diffusion and E-test failed to demonstrate carbapenem resistance. Carba NP test performed with 97.4% sensitivity and 95.7% specificity. The cphA gene was detected in A. veronii (21; 100%), A. hydrophila (18; 90%), A. dhakensis (34; 87.2%), A. jandaei (2; 50%), A. bestiarum (1; 100%) and not A. caviae . Discussion Phylogenetic analysis revealed A. dhakensis caused majority of infection, an unrecognised pathogen in this region. Carbapenem resistance due to cphA was prevalent. The Carba NP was a reliable phenotypic test. Adequate speciation and detection of carbapenem resistance in Aeromonas spp. is essential to guide appropriate antimicrobial therapy.

Outbreak due to a Klebsiella pneumoniae strain harbouring KPC-2 and VIM-1 in a German university hospital, July 2010 to January 2011

We describe the epidemiology and characteristics of the pathogen and patients (n=7) associated with an outbreak of a carbapenem-resistant Klebsiella pneumoniae (CRKP) strain in a German university hospital from July 2010 to January 2011. Species identification and detection of carbapenem resistance were carried out using standard microbiological procedures. Carbapenemases were detected by phenotypic methods and specific polymerase chain reactions (PCRs). DNA fingerprinting profiles were performed with repetitive sequence-based PCR. Medical records of colonised or infected patients were retrospectively reviewed. Antibiotic resistance profiles, PCR-specific amplification products and genotyping demonstrated that the outbreak occurred because of the spread of a single CRKP clone harbouring both KPC-2 and VIM-1. Five of the seven patients had invasive infections with the CRKP strain; the deaths of four of them were directly related to the infection. Early implementation of infection control interventions brought about efficient containment of further cross-transmission. Rapid dissemination of carbapenemase-producing Enterobacteriaceae is a serious concern in patient care and is a problem that has emerged in western Europe.

Mechanisms and detection of carbapenem resistance in Pseudomonas aeruginosa, Klebsiella pneumoniae, and Acinetobacter baumannii

Numerous mechanisms of resistance to the carbapenems have been described in Pseudomonas aeruginosa, Klebsiella pneumoniae, and Acinetobacter baumannii. Resistance to this class of agents can be divided into three main categories that include β-lactamases, efflux pumps, and changes in outer membrane porin proteins. Scant reports have also implicated penicillin-binding protein alterations in A. baumannii and P. aeruginosa. Inactivation of the carbapenems can be accomplished by a variety of β-lactam hydrolysing enzymes. The IMP and VIM metallo-carbapenemases, belonging to the molecular class B family, are the most worrisome of all β-lactamases because they confer resistance to the carbapenems and all other β-lactam agents with the exception of aztreonam. Several molecular class A, C and D β-lactamases have also demonstrated carbapenem hydrolysing activity but are less efficient in their capability. Efflux pumps, especially in P. aeruginosa, usually enhance resistance mediated by other mechanisms. Alterations in outer membrane porin proteins prevent or impede carbapenem penetration and subsequent binding to their targets in P. aeruginosa, K. pneumoniae, and A. baumannii. Finally, two or more of these mechanisms have been shown to act in concert to produce clinical resistance to carbapenems. Since expression of these mechanisms may be subtle, detection of carbapenem resistance in the clinical microbiology laboratory can be problematic.