Carbapenemase Production Research Articles

Prevalence and Risk Factors for Colonization with Carbapenem-Resistant Microorganisms in Patients Admitted to a Multidisciplinary Hospital

Relevance. In the last decade, there has been an increase in the isolation of antibiotic-resistant microorganisms in community settings. Colonization and asymptomatic carriage of extended-spectrum beta-lactamase and carbapenemase producers can be a precursor to the development of an infectious process and a significant factor in the pathogenesis of healthcare-associated infections. Understanding the risk factors for community-acquired colonization with antibiotic-resistant microorganisms is necessary for targeted screening and timely implementation of measures to prevent the spread of resistance in hospitals.The aim. To determine significant risk factors for colonization with antibiotic-resistant gram-negative microorganisms and carriage of carbapenem resistance genes in patients admitted to a multidisciplinary hospital.Materials & Methods. A prospective single-center crosssectional study was conducted at the Moscow Multidisciplinary Clinical Center «Kommunarka» from 15.09.2022 to 15.08.2023. The study included 733 patients aged 18 to 94 years. Biological samples were taken from the rectum, upper and lower respiratory tract. The obtained samples were examined by real-time polymerase chain reaction (PCR) with hybridization-fluorescent detection of amplification products to identify carbapenemase genes and by culture method to determine colonization with carbapenemresistant bacteria. Identification of isolated microorganisms was performed using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), and antibiotic susceptibility was determined by the Kirby-Bauer disk diffusion method on Mueller-Hinton agar. The results of susceptibility testing were interpreted based on EUCAST v12.0, v13.0, and v13.1 criteria.Results. Carriage of carbapenemase genes was detected in 12.6% of patients admitted to the hospital, while colonization with carbapenem-resistant bacteria was found in 2.7%. In the majority of patients (66.7%), the rectum was the only site of gene carriage. However, only 18.1% of these patients showed rectal colonization with carbapenem-resistant bacteria. This discrepancy is likely due to the higher sensitivity of molecular genetic methods compared to culture-based techniques. From a clinical perspective, the detection of nucleic acids by PCR can serve as an equivalent to pathogen detection in biological material. Multivariate analysis identified 5 independent predictors of colonization: cytostatic therapy, transfer from another hospital, need for vasopressor support, antibiotic use in the previous 3 months, and male gender.Conclusion. The identified risk factors allow for the identification of a highrisk patient cohort for targeted screening, enabling timely administration of appropriate antibiotic therapy and implementation of measures to prevent the spread of carbapenem resistance in the hospital.

Extended spectrum betalactamase and Carbapenemase producing gram negative bacteria from healthcare workers gowns at Debre Berhan Comprehensive Specialized Hospital, Ethiopia

Extended-spectrum beta-lactamase (ESBL) and carbapenemase-producing (CP) gram-negative bacteria are the major public health concerns. Gowns used by healthcare workers (HCWs) in daily practice are a source of hospital-acquired infections in hospital settings. The study aimed to determine the prevalence of extended-spectrum beta-lactamase and carbapenemase-producing gram-negative bacteria from gowns of healthcare workers at Debre Berhan Comprehensive Specialized Hospital, Amhara Regional State, Ethiopia. A hospital-based cross-sectional study was conducted from August to October 2022. A total of 226 swab samples were collected from gowns of HCWs and cultured on MacConkey agar. Bacterial identifications were done by standard biochemical tests. Screening for ESBL and carbapenemase production was done using CHROME agar. Confirmation of ESBL and carbapenemase production was done by the combination disk method and modified carbapenem inactivation method, respectively. Data were analyzed by using SPSS version 25. The overall contamination rate of gowns was 46.9% (106/226). Among 226 swab samples, a total of 117 (51.7%) gram-negative bacteria were isolated. Among these, the most frequent isolates were E. coli, accounted 36 (30.8%) followed by K. pneumoniae, 26(22.2%). The overall multi-drug resistance (MDR) rate was 65 (55.6%). Of the 117 isolates, 17(14.5%) and 12(10.3%) were ESBL and carbapenemase producers respectively. Gown type (p = 0.041), laundering practice (p = 0.045), number of gowns (p = 0.002), and gown washing frequency per week (p = 0.017).were significantly associated with bacterial contamination of gowns. In this study, the prevalence of ESBL and CP Gram-negative bacteria from gowns of healthcare workers was found to be alarming. Therefore, strict infection prevention and control practices, as well as good hygienic practices, should be implemented to reduce and prevent cross-contamination and the spread of antimicrobial-resistant strains in hospital settings.

Epidemiological Analysis of a K. pneumoniae NDM Outbreak in a Temporary Ward for Patients with Primary COVID-19 Infection

The COVID-19 pandemic made the medical community realize how large a problem it would face. The epidemiological situation forced the opening of additional wards, the so-called “COVID wards”, where an increase in the rate of coexisting bacterial infections was observed. We report a hospital outbreak due to New Delhi carbapenemases producing K. pneumoniae clones. Twenty-eight K. pneumoniae strains were analyzed from patients with primary COVID-19 infection. The drug susceptibility of the strains was determined by the diffusion–circulation method and E-test. Phenotypic and PCR methods confirmed the production of carbapenemases. The phylogenetic similarity of the obtained strains was examined using pulsed-field electrophoresis. Most strains were isolated from bronchoalveolar lavage. All isolates obtained were resistant to β-lactams and fluoroquinolones. All strains produced New Delhi carbapenemases and were classified into two genetic clusters, A and B. Eight risk factors for secondary bacterial infection were analyzed. Following an intervention involving hand hygiene, strict contact prevention, and cleaning of the hospital environment and medical devices, this outbreak was successfully brought under control.

Risk factors and molecular Epidemiology of colonizing Carbapenem-Resistant Enterobacterales in pediatric inpatient in Shenzhen, China

The spread of CRE has been rapid on a global scale and represents a significant challenge in nosocomial infections worldwide. The aim is to evaluate the risk factors for CRE colonization and to describe the molecular and clinical characteristics of CRE colonization in pediatric inpatients in Shenzhen, China. We collected stool specimens from 2474 randomly selected pediatric inpatient hospitalized in 2 pediatric hospitals in Shenzhen between January 2023 and December 2023 for subsequent microbiological analysis, including microbial culture, species identification, antimicrobial sensitivity testing, genetic characterization and multilocus sequence typing (MLST). In addition, we conducted a case-control study to identify potential risk factors for gastrointestinal CRE colonization. Of the 2474 non-replicating pediatric stool specimens collected, 3.6% (n=90) test positive for CRE. The most dominant CRE species were Escherichia coli (n=67, 74.5%), and Klebsiella pneumoniae (n=17, 19.0%). Multidrug resistance and carbapenemase production were observed in most CRE isolates. In CR E. coli and CR K. pneumoniae, the blaNDM was the predominant resistance gene, accounting for 95.5% and 76.5%, respectively. MLST showed considerable clonal diversity among the CR E. coli and CR K. pneumoniae isolates and the most common ST in CR E. coli was ST48 (n=6, 9.0%) and ST35 in CR K. pneumoniae (n=4, 23.5%). This study once again shows that pediatric inpatients in South China were colonized by a diversity of CRE strains, increasing the likelihood of difficult-to-treat infections. Hospitals and competent authorities should take appropriate public health measures, to prevent the further spread of CRE.

Use of Antimicrobial Photodynamic Therapy to Inactivate Multidrug-Resistant Klebsiella pneumoniae: Scoping Review.

Klebsiella pneumoniae is a Gram-negative bacillus responsible for a wide variety of potentially fatal infections and, in turn, constitutes a critical agent of healthcare-associated infections. Moreover, K. pneumoniae is characterized by multi-drug-resistant (MDR) bacteria, such as extended-spectrum beta-lactamases (ESBL) and carbapenemase (KPC) producer strains, representing a significant health problem. Because resistances make it difficult to eradicate using antibiotics, antimicrobial photodynamic therapy (aPDT) promises to be a favorable approach to complementing conventional therapy against MDR bacteria. This study aims to provide relevant bibliographic information on the state of the art of application of aPDT against K. pneumoniae and MDR K. pneumoniae. Our methodology follows a protocol using the PRISMA extension for scoping reviews (PRISMA-ScR) guidelines, and the search consults the PubMed (MESH), Google Scholar, and Scopus databases from January 2012 to September 2024. The eligibility criteria were (1) original articles after 2012 referring to antimicrobial photodynamic activity in K. pneumoniae in vitro and in vivo: clinical applications and synergism with antibiotics, other antimicrobial drugs, or PS coupled to other particles, (2) articles in English, and (3) articles peer-reviewed. Results. Following two independent searches in databases, 298 records were found. After applying eligibility criteria and various filters, such as removing duplicates, 25 studies were included in this review. The evidence demonstrates the effectiveness of aPDT in vitro in eradicating sensitive or MDR-K. pneumoniae strains, including strains producing biofilms, ESBL, and KPC. Finally, it is concluded that aPDT is a recommended antimicrobial therapy, but more research in vivo is needed to support studies in humans.

In-vitro activity of the novel β-lactam/β-lactamase inhibitor combinations and cefiderocol against carbapenem-resistant Pseudomonas spp. clinical isolates collected in Switzerland in 2022.

To evaluate the in-vitro activity of the novel commercially-available drugs, including meropenem-vaborbactam (MEV), ceftazidime-avibactam (CZA), ceftolozane-tazobactam (C/T), imipenem-relebactam (IPR) as well as cefiderocol (FDC), against carbapenem-resistant Pseudomonas spp. (CRP) isolates. All CRP isolates collected at the Swiss National Reference Laboratory (NARA) over the year 2022 (n = 170) have been included. Most of these isolates (n = 121) were non-carbapenemase producers. Among the 49 carbapenemase producers, 47 isolates produced metallo-β-lactamases (MBL) including NDM-1 (n = 11), VIM-like (n = 28), IMP-like (n = 7), and both NDM-1 and VIM-2 (n = 1) and two isolates produced the class A carbapenemase GES-5. Susceptibility testing was determined by broth microdilution method (BMD), or disk diffusion test, and results interpreted following EUCAST guidelines. The susceptibility rates for MEV, CZA, C/T and IPR were found to be 41%, 45%, 59% and 58%, respectively, for the whole set of isolates tested. Among non-carbapenemase producers, susceptibility rates for these β-lactam/β-lactamase inhibitors (BL/BLI) combinations were higher, determined at 55%, 61%, 83%, and 82%, respectively. The overall susceptibility of carbapenemase-producing Pseudomonas spp. to novel BL/BLI was relatively low, while 80% of these isolates demonstrated susceptibility to FDC, with a similar proportion (79%) observed among MBL producers. A total of 10 MBL-producing isolates (6%), mainly NDM-1, were found to exhibit resistance to all drugs tested, with the exception of colistin. FDC exhibited an excellent in-vitro activity against this collection of CRP recovered from Switzerland in 2022, including MBL producers. The new BL/BLI combinations displayed significant activity against non-carbapenemase CRP, with IPR and C/T showing the highest susceptibility rates.

Epidemiological and genetic characteristics of clinical carbapenemase-producing Enterobacterales isolates from Batna hospitals in Algeria

BackgroundCarbapenemase-producing Enterobacterales isolates are associated with significant mortality and have emerged as a major problem in healthcare settings worldwide.ObjectiveOur aim was to investigate the epidemiological and genotypic characteristics of carbapenemase-positive Enterobacterales isolates from patients hospitalised in three hospitals in the city of Batna, Algeria.MethodsBetween 2016 and 2019, a total of 5,316 clinical isolates were obtained. The collected isolates were identified using the VITEK-2 system. Demographic and microbiological data were collected as well as the antimicrobial susceptibility testing, phenotypic and molecular characterisation of carbapenemase and mcr-1 genes were performed.ResultsOut of the 5,316 isolates, 201 were carbapenem-resistant Enterobacterales isolates and 179 of them (89.05%) were positive for the production of carbapenemase, of which Klebsiella pneumoniae, Escherichia coli and Enterobacter cloacae were the most common. The blaOXA−48−like gene alone was detected in 147 isolates (82.12%) moreover, the blaNDM gene was detected in ten isolates (5.59%). Dual and triple combinations of carbapenemase genes were also observed here for the first time in Algeria: blaVIM and blaOXA−48−like; blaKPC, blaVIM and blaOXA−48−like; blaVIM and blaNDM; blaKPC, blaNDM and blaVIM; blaNDM and blaOXA−48−like genes. In addition, resistance to both colistin and carbapenem antibiotics was detected in eight isolates, however none of them was positive for the mcr-1 gene.ConclusionThis is the first study reporting the detection of carbapenemase genes in Klebsiella aerogenes, Enterobacter sakazakii, Raoultella ornithinolytica, Serratia ficaria, and Serratia marcescens and specific carbapenemase gene combinations in Algeria. The present study revealed that blaOXA−48−like were found to be the predominant carbapenemase genes in Batna hospitals.

Carbapenem-Resistant E. coli Adherence to Magnetic Nanoparticles.

Carbapenem-resistant Enterobacterales (CRE) is an emerging global concern. Specifically, carbapenemase-producing (CP) E. coli strains in CRE have recently been found in clinical, environmental, and food samples worldwide, causing many hospitalizations and deaths. Their rapid identification and characterization are paramount in control, management options, and treatment choices. Thus, this study aimed to characterize the cell surface properties of carbapenem-resistant (R) E. coli isolates and their interaction with glycan-coated magnetic nanoparticles (gMNPs) compared with carbapenem-susceptible (S) E coli. This study used two groups of bacteria: The first group included E. coli (R) isolates harboring carbapenemases and had no antibiotic exposure. Their initial gMNP-cell binding capacity, with cell surface characteristics, was assessed. In the second group, one of the E. coli (R) isolates and E. coli (S) had long-term serial antibiotic exposure, which we used to observe their cell surface characteristics and gMNP interactions. Initially, cell surface characteristics (cell morphology and cell surface charge) of the E. coli isolates were evaluated using confocal laser scanning microscope (LSCM) and a Zetasizer, respectively. The interaction of gMNPs with the E. coli isolates was assessed through LSCM and transmission electron microscope (TEM). Further, the gMNP-cell attachment was quantified as a concentration factor (CF) through the standard plating method. The results showed that the CF values of all E. coli (R) were significantly different from those of E. coli (S), which could be due to the differences in cell characteristics. The E. coli (R) isolates displayed heterogeneous cell shapes (rod and round cells) and lower negative zeta potential (cell surface charge) values compared to E. coli (S). Further, this research identified the differences in the cell surface characteristics of E. coli (S) under carbapenem exposure, compared to unexposed E. coli (S) that impact their attachment capacity. The gMNPs captured more E. coli (S) cells compared to carbapenem-exposed E. coli (S) and all E. coli (R) isolates. This study clearly found that differences in cell surface characteristics impact their interaction with magnetic nanoparticles. The gained insights aid in further understanding adhesion mechanisms to develop or improve bacterial isolation techniques and diagnostic and treatment methods for CRE.

Rapid detection of carbapenemase production in Aeromonas using phenotypic tests based on colorimetric microtube assay.

Antibiotic resistance, particularly carbapenem resistance, poses a significant global health threat due to the limited availability of effective antibiotics. Carbapenem-resistant Aeromonas are increasingly recognized for their role in various infections, necessitating rapid and accurate detection methods. This study aimed to evaluate several phenotypic tests, including the Carba NP test (CNPt), Carba NP-direct test (CNPd), and Blue-Carba test (BCT), for their effectiveness in rapidly detecting carbapenemase production in Aeromonas. These tests target both the chromosomally encoded CphA metallo-β-lactamase (MBL) and acquired carbapenemases. Additionally, a modified phenotypic test called the Colony-Carba NP test (c-CNPt) was introduced to enhance sensitivity and specificity. A retrospective analysis was conducted on 131 clinically conserved Aeromonas strains harboring identified carbapenem resistance genes, using CNPt, CNPd, BCT, and the newly developed c-CNPt and EDTA-Colony-Carba NP test (ec-CNPt). The stability of c-CNPt reagents stored at -80°C was also assessed. Additionally, a prospective study conducted from July 2021 to November 2023 evaluated 152 Aeromonas isolates to determine the clinical applicability of these tests. Our results demonstrated that CNPd and BCT achieved 100% sensitivity and specificity, surpassing the traditional CNPt, which showed only 63.6% sensitivity for Aeromonas strains. The c-CNPt also showed 100% sensitivity and specificity, with the ec-CNPt effectively differentiating between MBL and serine carbapenemase types. Stability tests confirmed that c-CNPt reagents could be stored at -80℃ for up to 1 year without performance degradation. These findings highlight the practicality and reliability of these phenotypic tests for routine laboratory use, providing a rapid and cost-effective method for detecting carbapenemase production.The rapid detection of carbapenemase production in Aeromonas is of paramount importance due to the significant clinical and public health implications associated with antibiotic resistance. The development and validation of rapid phenotypic tests such as the Colony-Carba NP test (c-CNPt) and the EDTA-Colony-Carba NP test (ec-CNPt) are crucial advancements in the field. These tests offer a highly sensitive and specific method for detecting carbapenemase production in Aeromonas, including the differentiation between metallo-β-lactamase and serine carbapenemases. The c-CNPt and ec-CNPt are cost-effective, easy to perform, and provide rapid results, making them suitable for routine clinical use. Additionally, the stability of the reagents ensures their practicality for long-term application in various healthcare settings. Implementing these phenotypic tests in clinical laboratories can significantly enhance the early detection and appropriate treatment of carbapenem-resistant Aeromonas infections.

A Rare Report of Carbapenem Resistant Vibrio fluvialis Isolated from a case of Walled off Necrosis: A Sequelae of Acute Necrotising Pancreatitis

Vibrio fluvialis (V. fluvialis) is commonly found in coastal environments and is an emerging pathogen encountered in diarrhoeal outbreaks and sporadic extraintestinal cases. V. fluvialis infections usually manifest as watery bloody diarrhoea, nausea, vomiting, gastroenteritis and peritonitis. In this case report, an unusual presentation of Multidrug Resistant (MDR) V. fluvialis along with Klebsiella pneumoniae co-infection from a case of Walled Off Necrosis (WON)- A complication of Acute Necrotising Pancreatitis (ANP) is discussed. The patient presented with the acute abdomen and had peripancreatic collection for which Ultrasound (USG) guided 12F pigtail drain placed over the right lower quadrant of the abdomen and conservatively managed. Routine cultures were done and the growth on Sheep Blood Agar (SBA) plate and MacConkey (MAC) agar plates were subjected for automated phenotypic identification by Matrix Assisted Laser Desorption Ionisation Time of Flight-Mass Spectrometry (MALDITOF-MS) and Vitek-2 systems and was identified as V. fluvialis. Also, molecular tests like 16S rRNA Polymerase Chain Reaction (PCR) followed by Sanger’s sequencing was done and the identification was further confirmed. Phenotypic RESIST-5 TRURAPID O.K.N.V.I. commercial lateral flow immunochromatographic assay for detection of clinically relevant and common carbapenemase genes like NDM, OXA-48, VIM, IMP and KPC was done which revealed this V. fluvialis isolate as New Delhi Metallo betalactamase (NDM) type of Carbapenemase producer. Patient was managed with levofloxacin and doxycycline and patient condition improved and was discharged.

Detection and characterization of carbapenemase-producing Enterobacteriaceae in cancer patients: first Sri Lankan report of blaVIM in Enterobacteriaceae.

Carbapenem-resistant Enterobacteriaceae (CRE) are an important cause of infections in cancer patients. The proportion of carbapenem resistance and the types of carbapenemase-encoding genes in Enterobacteriaceae isolated from cancer patients were determined in this study. Bacteria isolated from adult, in-ward cancer patients with lower respiratory tract infections (LRTI), skin and soft tissue infections (SSTI), or urinary tract infections (UTI) were included in the study. Enterobacteriaceae were identified up to the species level by API® 20E test kits. Carbapenem resistance was defined as non-susceptibility to either imipenem or meropenem in the disc diffusion test. Major carbapenemase-encoding genes (blaKPC, blaNDM, blaOXA-48, blaIMP, and blaVIM) were detected by the GeneXpert® Carba-R real-time PCR instrument. Enterobacteriaceae comprised 57% (94/165) of the bacterial isolates. Carbapenem resistance among Enterobacteriaceae was 46.8% (44/94). Klebsiella pneumoniae (65.9%, 29/44) was the predominant CRE isolate followed by Escherichia coli (25%, 11/44). The majority of CRE isolates (72.7%, 32/44) had a meropenem MIC of ≥ 32 µg/mL. Carbapenemase-encoding genes were identified in 43 of the 44 CRE isolates. blaNDM was the most prevalent carbapenemase-encoding gene and was detected in 67.4% (29/43) of Enterobacteriaceae isolates. No isolate was positive for blaIMP. Sixteen (37.2%) isolates co-harbored more than one carbapenemase-encoding gene. Two Enterobacteriaceae isolates were found to harbor blaVIM. Nearly all CRE isolated in this study were carbapenemase producers. This study documented the emergence of blaVIM harboring Enterobacteriaceae for the first time in Sri Lanka.

Carbapenemase producing Gram Negative Bacilli (GNB) isolated from patients in a tertiary care hospital in South India – a prospective observational study.

Carbapenemase producing Gram Negative Bacilli (GNB) isolated from patients in a tertiary care hospital in South India – a prospective observational study.

Risk Factors for Infections Caused by Extended-Spectrum Beta-Lactamase Producing and Carbapenem-Resistant Enterobacterales in Pediatric Critical Care Settings: A Case-Control Study

Background: Infections due to Gram-negative resistant bacterial pathogens are a major concern in intensive care units (ICUs). Risk factors for extended-spectrum beta-lactamase (ESBL)–producing enterobacterales (ESBL-PE) and carbapenem-resistant enterobacterales (CRE) infections in pediatric critical care settings remain unclear. Methods: This was a retrospective case-control study of infections due to ESBL-PE and CRE during a 5-year period (2016–2021). Control cases were matched for age, infection site and year of infection, but their cultures grew enterobacterales that were non-ESBL or carbapenemase producers. Results: A total of 57 patients with ESBL-PE or CRE infections (cases) and 59 control patients were included. The majority of organisms were Escherichia coli and Klebsiella species recovered from the respiratory tract. There was no difference in prior hospital admission, pediatric ICU, or neonatal ICU stay during the previous 6 months, indwelling devices, comorbid conditions, or surgery in the last 6 months (P > 0.3). Risk factors evaluated by univariate analysis included the history of antibiotic use in the last 6 months, antibiotic treatment with cephalosporins including cefepime, cephalosporins treatment duration ≥7 days, treatment with trimethoprim/sulfamethoxazole and carbapenems and vancomycin use ≥ 7 days. However, multivariate logistic regression analysis showed that cefepime use ≥ 7 days was the single best predictor for cases with an odds ratio of 2.205-fold (95% confidence interval, 1.403–3.466; P < 0.001). Conclusions: Cefepime use ≥ 7 days was the most predictive risk factor of ESBL-PE and CRE acquisition. The study further underscores the need for optimizing antimicrobial stewardship practices to limit unnecessary and prolonged use of antibiotics to prevent the emergence of resistant pathogens.

Characterization of carbapenem-resistant Enterobacterales and Pseudomonas aeruginosa carrying multiple carbapenemase genes-Antimicrobial Resistance Laboratory Network, 2018-2022.

Carbapenem-resistant Enterobacterales (CRE) and carbapenem-resistant Pseudomonas aeruginosa (CRPA) are significant public health threats, particularly when harboring carbapenemases. Literature describing the frequencies and phenotypic and genotypic characteristics of isolates harboring multiple carbapenemase genes is limited. Using data collected from the Antimicrobial Resistance Laboratory Network (AR Lab Network) in 2018-2022, we describe CRE and CRPA isolates that harbor multiple acquired carbapenemase genes. Clinical laboratories submitted CRE and CRPA isolates to AR Lab Network public health laboratories for additional characterization that included antimicrobial susceptibility testing and detection of five targeted carbapenemase genes. Isolates were classified as non-carbapenemase producing (non-CP) when negative for carbapenemase production and all targeted carbapenemase genes, or positive for a single-CP (SCP) or multiple-carbapenemase (MCP) targeted gene. Among 79,799 CREs tested, 27,599 (35%) were SCP and 611 (1%) were MCP. MCP-CRE most often carried blaKPC/blaNDM (n = 285, 47%). Both SCP-CRE and MCP-CRE were most commonly Klebsiella spp. Enterobacter spp. and Escherichia coli isolates harboring MCP were detected at slightly higher frequencies (18% and 15%; n = 109 and n = 88, respectively) than Enterobacter spp. and Escherichia coli isolates harboring SCP (13% and 13%; n = 3,653 and 3,471, respectively). The number of MCP-CRE detected increased from 54 of 5,105 (1%) in 2018 to 223 of 6,994 (3%) in 2022. Among 54,490 CRPA tested, 2% (n = 1,249) were SCP and 31 were MCP. MCP-CRPA most often carried blaVIM/blaIMP (n = 13, 42%). A higher proportion of MCP-CRE (97%, n = 330) isolates were categorized as resistant to meropenem, compared to SCP-CRE (79%; n = 11,227) and non-CP (13%; n = 2,683). Although MCP organisms represent a small proportion of total CP detected in the AR Lab Network, there is a need for continued monitoring and additional research.IMPORTANCECarbapenemase-producing organisms are of significant clinical and public health concerns, and rapid detection and containment of such threats are vital to preventing their spread. In this article, we used a collection of over 130,000 contemporary isolates to evaluate frequencies and phenotypic and genotypic properties of CRE and CRPA isolates harboring multiple carbapenemase genes across the United States, from 2018 to 2022. Of note, 95% and 100% of CRE and CRPA isolates co-harbored at least one metallo-β-lactamase gene, respectively, indicating a high proportion of isolates originating from patients with difficult-to-treat infections. Both clinical and public health professionals across the nation can use these data and key findings to better understand the molecular landscape of these isolates. Timely detection and control of these organisms are essential to combating the spread of antibiotic resistance and ensuring the availability of effective treatment options for patients.

Emerging Challenges and Innovations in the Management of Carbapenem-resistant Enterobacteriaceae Infections in Hospital Settings”

Carbapenem-resistant Enterobacteriaceae represent a crucial global public health issue. The challenges associated with carbapenem-resistant Enterobacteriaceae are multifac-eted. This review article aims to explore and comprehend the emerging challenges and the latest developments in the management of carbapenem-resistant Enterobacteriaceae infec-tions. A comprehensive literature search was conducted using databases such as PubMed, Cochrane Library, and Embase. Studies published from database inception until May 2024 were included. Articles were selected based on relevance, study design, and quality. Data from clinical trials, observational studies, and reviews were synthesized to provide a detailed over-view of the current state of knowledge on carbapenem-resistant Enterobacteriaceae. The re-view identifies key epidemiological trends, including geographic variations and risk factors associated with carbapenem-resistant Enterobacteriaceae. Mechanisms of resistance are elu-cidated, focusing on carbapenemase production and other related factors. Current treatment options are assessed, with an emphasis on newer antibiotic combinations such as ceftazidime/avibactam, meropenem/vaborbactam, ceftolozane/tazobactam, and cefepime/en-metazobactam. The review also highlights emerging therapeutic approaches, including novel antibiotics and non-traditional approaches like phage therapy, fecal microbiota transplanta-tion, probiotics, antimicrobial peptides, vaccines, and herbal drugs. Additionally, the review also reflects on effective infection prevention and control strategies. While research efforts to explore newer combinations and alternate approaches to treat carbapenem-resistant Entero-bacteriaceae infections are crucial, the importance of stringent infection prevention and con-trol strategies cannot be overstated. This dual focus is essential to address both the immediate and long-term challenges posed by carbapenem-resistant Enterobacteriaceae

Extended-spectrum β-lactamase and carbapenemase producing Enterobacteriaceae among patients suspected with surgical site infection at Hospitals in Southern Ethiopia.

Extended-spectrum β-lactamase and carbapenemase-producing Enterobacteriaceae are an increasing problem for patients today. Data on clinical samples for ESBL and carbapenemase-producing Enterobacteriaceae for surgical site infection patients in developing countries are limited, including Ethiopia, mainly due to resource constraints. Hence, this study aimed to determine the prevalence of extended-spectrum beta-lactamase- and carbapenemase-producing Enterobacteriaceae among patients suspected to have surgical site infection at Hospital in Southern Ethiopia. A hospital-based cross-sectional study was conducted on 422 suspected surgical site infections from June 1, 2022 to August 30, 2022 at Hospitals in Southern Ethiopia. Sociodemographic and clinical data were obtained by using a structured questionnaire. Clinical samples (pus, pus aspirates, and wound swabs) were collected aseptically and processed within 30 min by placing the swabs in sterile test tubes containing sterile normal saline (0.5 mL). Samples were cultured on blood and MacConkey agar plates. All positive cultures were characterized by colony morphology, Gram staining, and standard biochemical tests. Antimicrobial sensitivity tests were performed using Kirby Baur disk diffusion on Mueller-Hinton agar. ESBL production was confirmed using a double-disc synergy test (DDST) method. Carbapenemase production was assessed using the modified Hodge test. Logistic regression analysis was used to determine associated factors. A P-value < 0.05 were considered statistically significant. Bacteria belonging to the order Enterobacterales were cultured in 23.7% out of 422 patients with suspected surgical wound infection. Of all the isolates, Enterobacteriaceae (69 isolates) were the most frequent, with E. coli (29/69) followed by K. pneumoniae (14/69). Of 69 Enterobacteriaceae isolates, 66.6 % (46/69) were positive for ESBL production, and 21.7 (15/69) were positive for carbapenemase-producing Enterobacteriaceae. The majority of Enterobacteriaceae isolates showed sensitivity to meropenem (72.1%); however revealed 63.9% and 70.5% were resistant to gentamicin and ciprofloxacin, respectively. Similarly, a higher resistance rate to cefepime (91.8%), amoxicillin-clavulanic acid (98.4%), ceftriaxone (95.1%), and ceftazidime (91.8%). MDR rate of Enterobacteriaceae isolates was 25/61 (41%) among patients suspected for surgical site infection. The Multivariable analysis revealed that length of hospital stay in hospital [AOR = 3.81 (95% CI 2.08-6.95)] remained statistically significant factor associated with surgical site infection due to ESBL producing Enterobacteriaceae. Study results showed the severity of ESBL-producing Enterobacteriaceae is critical and CPE is alarming. Meropenem is the most effective antibiotic against the ESBL-producing Enterobacteriaceae. MDR rate of Enterobacteriaceae isolates was 61 (61%) among patients suspected for surgical site infection. Therefore, antibiotic selection should be based on the results of the culture and sensitivity tests.

Commercial Day-Old Chicks in Nigeria Are Potential Reservoirs of Colistin- and Tigecycline-Resistant Potentially Pathogenic Escherichia coli.

Background: Frequent use of colistin (COL) and tetracyclines in the Nigerian poultry sector potentially triggers bacterial resistance against COL and tigecycline (TIG), which are last-line antibiotics used to treat multidrug-resistant infections. Aim/Objectives: This study aimed to isolate COL- and TIG-resistant E. coli from commercial day-old chicks distributed to poultry farmers in Nsukka Southeastern Nigeria, assess the production of extended-spectrum β-lactamase (ESBL) and carbapenemase by the isolates, and establish their pathogenic potentials. Materials and Methods: Non-duplicate cloacal swabs were systematically collected from 250 randomly selected day-old chicks. MacConkey agar with 1 µg/mL of COL and 16 µg/mL of tetracycline was used for the isolation of putative COL- and tetracycline-resistant E. coli, respectively. E. coli isolates were confirmed biochemically using the API20E Gram-negative identification kit and molecularly by polymerase chain reaction targeting the uidA gene. Phenotypic COL resistance was established using COL agar and COL disc elution tests, while TIG insusceptibility was determined with disc diffusion. ESBL and carbapenemase production was assessed by double-disc synergy and modified carbapenem inactivation methods, respectively. Pathogenic potentials were determined using phenotypic methods. Results: COL- and TIG-resistant E. coli was recovered from 95 (38.0%) and 62 (24.8%) swabs from the 250 chicks, respectively. None of the isolates were potential ESBL or carbapenemase producers. The COL-resistant isolates displayed pathogenic potentials such as biofilm formation, haemagglutination, cell surface hydrophobicity, surface layer, and gelatinase activities at rates of 30.7%, 8.4%, 33.7%, 23.5%, and 17.6%, respectively. Meanwhile, the TIG-resistant isolates exhibited their respective potentials at rates of 47.0%, 21.0%, 35.5%, 58.1%, and 43.6%. Red, dry, and rough (RDAR) was the predominant curli fimbriae, and the cellulose morphotype portrayed by both the COL- and TIG-unsusceptible potential biofilm-producing isolates. Conclusions: This study demonstrates that a significant percentage of commercial day-old chicks distributed to farmers in Nsukka, southeastern Nigeria, are colonized by potentially pathogenic COL- and TIG-resistant E. coli, which could spread to humans and the environment.

A comparison of two MALDI-TOF MS based assays for the detection of carbapenemases in Enterobacterales

Carbapenem resistant (CRE) and carbapenemase producing Enterobacterales (CPE) in particular, represent a major threat for healthcare systems worldwide. Rapid, reliable, and easy to perform assays are required to enable targeted and effective therapy. MALDI-TOF MS based carbapenemase diagnostics has potential advantages over molecular and phenotypic sensitivity tests, especially in terms of time to result. So far, only one mass spectrometry (MS)-based carbapenemase test system is commercially available for routine use. The aim of this study was to compare the performance of the established system to a novel MS-based test to identify CPE isolates. Forty consecutive CRE isolates (70% CPEs) were pre-screened for carbapenemase activity by routine laboratory methods. Isolates then were tested using the to date only IVD CE certified MALDI-TOF MS carbapenemase detection assay (MBT STAR-Carba IVD Kit; Bruker Daltonics) and a novel test designed for the recently launched EXS2600 MALDI-TOF MS system (Carbapenemase Activity Kit; Zybio). Valid results were obtained for 93% and 85% isolates by the Bruker and the Zybio assay, respectively. Sensitivities, specificities, positive and negative predictive values were 92%, 91%, 96%, and 83% for the Bruker assay and 96%, 64%, 85%, and 88% for the Zybio assay. There are notable differences concerning the handling of the assays. In summary, both systems featured high sensitivities for the detection of carbapenemases, but the Bruker assay yielded less false-positive results. There are advantages and disadvantages concerning the handling for each system, but both proved to be suitable for the use in a routine laboratory.

Public health concern of antimicrobial resistance and virulence determinants in E. coli isolates from oysters in Egypt

The emergence of critical-priority E. coli, carrying a wide array of resistance and virulence factors through food sources, poses a significant challenge to public health. This study aimed to investigate the potential role of oysters sold in Egypt as a source for E. coli, identify their resistance and virulence-associated gene profiles, and assess associated zoonotic risks. A total of 33 pooled fresh oyster samples were obtained from various retail fish markets in Egypt and examined bacteriologically for the presence of E. coli. Antimicrobial resistance was performed by the disk-diffusion method, and the multiple antibiotic resistance index (MAR) was calculated. All isolates were screened for extended-spectrum beta-lactamase (ESBL) (blaTEM, blaSHV, blaCTX−M, and blaOXA−1), plasmid-mediated AmpC blaCMY−2, and carbapenemases (blaKPC, blaNDM, blaVIM, and blaOXA−48) genes by Polymerase chain reaction. Moreover, the presence of virulence-encoding genes was investigated. The virulent MDR strains were clustered using R with the pheatmap package. The prevalence of E. coli was 72.7% (24 out of 33), with 66.7% of the isolates classified as multi-drug resistant, and 75% exhibited MAR values exceeding the 0.2 threshold. Different antimicrobial sensitivity phenotypes and genotype profiles were identified in E. coli isolates. The most prevalent gene detected among all isolates was blaTEM (22/24, 91.7%). Notably, all non-ESBL producers were positive for blaCMY2. Carbapenem-resistant and carbapenem-intermediate strains were carbapenemase producers, with the predominance of the blaKPC gene (11/24, 45.8%). Remarkably, twelve out of sixteen virulence genes were identified, with papC (21/24, 87.5%) and sfa (16/24, 66.7%) genes being the most prevalent. Most isolates carry virulence genes primarily associated with extra-intestinal pathogenic E. coli (ExPEC) (87.5%) and enteropathogenic (EPEC) (70.8%) pathotypes. Four E. coli isolates exhibit cluster patterns. This study provides the first insight into the emergence of virulent MDR E. coli among oysters in Egypt. It underscores the potential role of oysters as a source for disseminating these strains within aquatic ecosystems, presenting a possible threat to public health.

Faecal carriage of extended-spectrum beta-lactamase and carbapenemase-producing enterobacterales among HIV patients at Jimma Medical Center, Southwest Ethiopia

BackgroundEnterobacterales infections in immunocompromised individuals are associated with considerable morbidity, mortality, and health care costs. This study aimed to assess the faecal carriage of extended-spectrum β-lactamase (ESBL) and carbapenemase-producing Enterobacterales (CPE) among HIV-infected patients at Jimma Medical Center. A total of 344 stool samples were collected and inoculated on Mac-Conkey and Eosin-Methylene Blue agar and incubated at 35–37 °C aerobically. ESBL and carbapenemase production were detected using D68C ESBL/AmpC and D73C CARBA plus (Mast Group, UK).ResultsA total of 376 Enterobacterales were isolated. The prevalence of ESBL-PE and CPE carriage rate was 13.3% (50/376) and 4.3% (16/376) respectively. The highest proportion of ESBL producing isolates were found in K. pneumoniae 29.0% (9/31) followed by E. coli 13.4% (39/292). Similarly, K. pneumoniae 12.9% (4/31) was the most common carbapenem-resistant isolate followed by E. coli 3.8% (11/292). Multi-drug resistance was observed in 66.5% (250/376) of the isolates. Prior cephalosporin use (AOR = 7.9; 2.31–27.29), CD4 count (≤ 350 cells/µL) (AOR = 3.8; 1.12–12.9), and comorbidities (AOR = 2.3; 1.24–4.32) were significantly associated with ESBL production. Additionally, cephalosporin use (AOR = 6.34; 1.27–31.66) was significantly associated with the presence of CRE.ConclusionsThis study revealed a high prevalence of ESBL-PE and CPE among HIV patients, with K. pneumoniae and E. coli being the dominant isolates. MDR was common, with key risk factors being prior cephalosporin use, low CD4 counts, and comorbidities. These findings emphasize the need for enhanced infection prevention and control, regular screening, and improved antibiotic stewardship to curb the spread of resistant bacteria in immunocompromised individuals.