Phenotypic and molecular identification of carbapenemase-producing Enterobacteriaceae - challenges in diagnosis and treatment

Abstract Introduction: Infections due to carbapenemase-producing carbapenem-resistant Enterobacteriaceae (CPCRE) are an emerging global public health threat. The purpose of this study was to investigate phenotypic and genotypic features of CP-CRE strains isolated from hospitalized patients. Material and methods: Between 1st of January - 1st of July 2017, in the Department of Microbiology, “Dr. Constantin Opriş” County Emergency Hospital Baia Mare, Romania, 1110 strains of Enterobacteriaceae were isolated from bronchial secretions, urine, wounds and blood cultures. Bacterial identification and antimicrobial susceptibility tests were performed by conventional methods, Vitek 2 Compact and M.I.C.E. strips. We analysed all Enterobacteriaceae strains non-susceptible to carbapenems according to CLSI 2017 criteria. The modified Hodge test (MHT), the modified carbapenem inactivation method (mCIM) and the combination disks test (KPC, MBL, OXA-48 Confirm kit, Rosco Diagnostica) were used for phenotypic confirmation, whereas a multiplex PCR assay for genes blaKPC, blaNDM and blaOXA-48 was used for genetic confirmation. Results: 19 non-duplicate strains isolated from 16 patients were phenotypically identified as CP-CRE: Klebsiella pneumoniae (n=14), Escherichia coli (n=2), Providencia stuartii (n=2) and Serratia marcescens (n=1). Most strains were isolated from bronchial secretions (n=9). The carbapenem-hydrolizing enzymes were identified by the combination disks test as: KPC (n=9), OXA-48-like (n=5) and MBL (n=5). Molecular confirmation was performed in 18 phenotypically positive isolates with 100% concordant results with mCIM and combination disks test. Discrepant results were noticed with the MHT in case of 4 NDM-producers confirmed by PCR. All CP-CRE strains were resistant to all tested cephems. Three out of 9 K. pneumoniae strains tested against colistin were found resistant. Conclusions: The most common carbapenemase detected was KPC. Therapeutic options were limited in all positive cases. Rapid and reliable detection of CP-CRE is critical for preventing the spread of these pathogens

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Molecular Epidemiology and Characterization of Carbapenem-Resistant Klebsiella pneumoniae Isolated from Urine at a Teaching Hospital in Taiwan

Microorganisms ◽

10.3390/microorganisms9020271 ◽

2021 ◽

Vol 9 (2) ◽

pp. 271

Author(s):

Yuarn-Jang Lee ◽

Chih-Hung Huang ◽

Noor Andryan Ilsan ◽

I-Hui Lee ◽

Tzu-Wen Huang

Keyword(s):

Klebsiella Pneumoniae ◽

Teaching Hospital ◽

Efflux Pump ◽

Resistance Mechanisms ◽

Pcr Analysis ◽

Carbapenem Resistant ◽

High Prevalence ◽

Antimicrobial Susceptibility Tests ◽

Susceptibility Tests ◽

Tract Infections

Urinary tract infections (UTIs) are common in clinics and hospitals and are associated with a high economic burden. Enterobacterium Klebsiella pneumoniae is a prevalent agent causing UTIs. A high prevalence of carbapenem-resistant K. pneumoniae (CRKP) has emerged recently and is continuing to increase. Seventeen urinary CRKP isolates collected at a teaching hospital in Taiwan from December 2016 to September 2017 were analyzed to elucidate their drug resistance mechanisms. Two-thirds of the isolates were obtained from outpatients. Antimicrobial susceptibility tests demonstrated multidrug resistance in all the isolates. Multilocus sequence typing analysis showed high diversity among the isolates. PCR analysis demonstrated the presence of carbapenemases in three isolates. All isolates carried at least one other extended-spectrum β-lactamase, including TEM, DHA, and CTX-M. Fifteen isolates contained mutations in one of the outer membrane porins that were assessed. The expression levels of the acrB and/or oqxB efflux pump genes, as determined by qRT-PCR, were upregulated in 11 isolates. Six isolates might have utilized other efflux pumps or antimicrobial resistance mechanisms. These analyses demonstrated a highly diverse population and the presence of complex resistance mechanisms in urinary isolates of K. pneumoniae.

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THE FIRST INVESTIGATION OF AAC(6’)-Ib ENZYME IN CARBAPENEM-RESISTANT ENTEROBACTERIACEAE ISOLATED FROM INDONESIAN PATIENTS

Acta Biochimica Indonesiana ◽

10.32889/actabioina.v2i1.32 ◽

2019 ◽

Vol 2 (1) ◽

pp. 8-14

Author(s):

Beauty Novianty ◽

Ella Amalia ◽

Ziske Maritska ◽

Yuwono Yuwono ◽

Lusia Hayati

Keyword(s):

Resistance Mechanism ◽

Test Results ◽

Gram Negative ◽

Therapy Options ◽

The Past ◽

Carbapenem Resistant ◽

Long Time ◽

Pcr Method ◽

Vitek 2 ◽

Carbapenem Resistant Enterobacteriaceae

Background: Over the past decade, numbers of Carbapenemase Producing-Carbapenem Resistant Enterobacteriaceae (CP-CRE) has been increasing worldwide and it has been becoming a threat because of its resistance against carbapenem which is considered as the “last resort” antibiotic. Therapy options for its infection are still limited. Aminoglycoside serves as one of the most commonly used antibiotics, but the resistance against it has already been presented for a long time. Aminoglycoside Modifying Enzyme (AME) is the most important resistance mechanism against aminoglycoside. AAC(6’)-Ib enzyme is one of the most common AME produced by the gram-negative bacteria.Objectives: This study wished to identify the gene of this enzyme among CRE isolated from infected Indonesian patients in Dr. Mohammad Hoesin Hospital Palembang.Methods: Twenty-eight isolates collected from CRE-infected patients identified by Vitek 2 Compact (bioMerieux, USA) in dr. Mohammad Hoesin Hospital Palembang during September—November 2017. AAC(6’)-Ib gene was identified using PCR method, then visualize by electrophoresis. The result is then analyzed by comparing it with a susceptibility test. Results: Out of 28 samples, AAC(6’)-Ib is identified in 22 (78.57%) samples. Samples with AAC(6’)-Ib showed to be less resistant to various antibiotics, significantly to amikacin (p=0.023).Conclusion: AAC(6’)-Ib gene is found in most of samples implying its frequent occurrence in Indonesian patients.

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490. High Prevalence of Rectal Carriage of blaKPC –Mediated Carbapenem-Resistant Enterobacteriaceae Among Community Food Handlers in Kuwait

Open Forum Infectious Diseases ◽

10.1093/ofid/ofz360.2509 ◽

2019 ◽

Vol 6 (Supplement_2) ◽

pp. S239-S239

Author(s):

Noura Al-Sweih ◽

Ola Moghnai ◽

Vincent O Rotimi

Keyword(s):

Healthy Food ◽

Food Handlers ◽

Carbapenem Resistant ◽

Gcc Countries ◽

High Prevalence ◽

The World ◽

Genes Encoding ◽

Vitek 2 ◽

Very High ◽

Carbapenem Resistant Enterobacteriaceae

Abstract Background Carbapenemases are diverse enzymes which inactivate the carbapenems. KPC-producing carbapenemase-producing Enterobacteriaceae have disseminated to many regions in the world, however, anecdotal reports of KPC-producing CPE in some GCC countries excluding Kuwait. In this study we report the first emergence of the KPC producing CPE isolated from healthy food handlers in our community. Methods Rectal swabs were collected from 405 food handlers. Isolates were identified by VITEK 2 and their susceptibility to 21 antibiotics performed by MIC determination using Etest. Genes encoding carbapenemase production were characterized by PCR and clonality of isolates was determined by MLST. Results A total of 36 CPE were isolated from 31 participants, of which 15 (41.7%) were Escherichia coli and 8 (22.2%) Klebsiella pneumoniae. All isolates were susceptible to amikacin and tigecycline but an alarmingly high percentage (38.9%) were non-susceptible to colistin. A very high proportion of the CPE harbored blaKPC (58.3%), followed by blaOXA-48 (25%), blaNDM (5.6%) and blaVIM (2.8%). Carbapenemases were co-produced with ESBLs in 30.6% of the isolates. Sequencing of the KPC revealed that KPC-18 represented 45%, KPC-2 36% and KPC-29 18%. Considerable genetic diversity among the isolates was identified by MLST assays demonstrating the emergence of new clones. Five diverse new CPE clones were detected from three Bangladeshi citizens and 2 Indians. Conclusion Our finding demonstrates a relatively high colonization rate (8.9%) of healthy food handlers by CPE of which KPC-producing CPE were predominant; this is an unusual finding in Kuwait representing the first of such findings in our country and GCC. Disclosures All authors: No reported disclosures.

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532. Can Saccharomyces boulardii Therapy Be Effective in Decolonizing Rectal Carbapenem-Resistant Enterobacteriaceae (CRE) Colonization?

Open Forum Infectious Diseases ◽

10.1093/ofid/ofz360.601 ◽

2019 ◽

Vol 6 (Supplement_2) ◽

pp. S255-S256

Author(s):

Oguz Resat Sipahi ◽

Gunel Quliyeva ◽

Feriha Cilli ◽

Nilgun Deniz Kucukler ◽

Demet Dikis ◽

...

Keyword(s):

Susceptibility Testing ◽

Rectal Swab ◽

Saccharomyces Boulardii ◽

Inclusion Criteria ◽

Randomized Controlled ◽

Promising Tool ◽

Carbapenem Resistant ◽

History Of ◽

Vitek 2 ◽

Carbapenem Resistant Enterobacteriaceae

Abstract Background CRE are globally important pathogens associated with significant morbidity and mortality. The problem of carrying CRE may continue to create a problem in discharged cases in the community. Saccharomyces boulardii sachet therapy (SBST) is reported to cause decolonization in several MDR bacteria carriers. Herein, it is aimed to present the decolonizing rates of rectal CRE colonized cases after SBST treatment. Methods The study period was August 2018–March 2019. Inclusion criteria were: (i) age >18, (ii) receiving Saccharomyces boulardii 250 mg sachets q12h for 7 days, (iii) being proven CRE carrier on rectal swab culture (RSC) up to 5 days period before SBST. The first repeated RSC was performed 3–5 days after the end of SBST. Data were retrieved from the hospital electronic database. Cases with three consecutive weekly performed negative RSC were considered to be decolonized. RSC were processed according to CDC protocol; briefly, the swab was inoculated into 10 mL of trypticase soy broth (bioMérieux Inc., Marcy-l’Étoile, France) with the addition of one 10-μg ertapenem disk (Oxoid, Altrincham, UK) and incubated at 35°C for 18–20 h. The next day, after vortexing, 100 μL of the inoculum was subcultured (8) onto chromID CARBA agar plates (bioMérieux) and incubated at 35°C for 18–20 h. Suspected CRE colonies on chromID CARBA (blue/green to blue/gray in color) were identified by the VITEK MS system (bioMérieux). Susceptibility testing of the isolates was performed with the VITEK 2 system (bioMérieux). Isolates were tested for their resistance phenotypes to imipenem, ertapenem, and meropenem by E-test (bioMérieux). The results were interpreted according to the EUCAST criteria. Results Fifteen cases [2 women, mean age 60.6 ± 18.3 (min. 18–max. 83)] fulfilled the inclusion criteria. All had a history of carbapenem usage. Five cases (33%) had three consequent negative RSC after SBST and were considered to be decolonized. Twelve cases were receiving concomitant antibiotic during SBST (10 carbapenem based regimens). Three cases who received no concomitant antibiotic were decolonized. Conclusion SBST may be a promising tool for decolonizing CRE carriers. These data need to be validated in larger cohorts preferably via randomized-controlled trials. Disclosures All authors: No reported disclosures.

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Epidemiology and risk factors for carbapenem-resistant Enterobacteriaceae colonisation and infections: case-controlled study from an academic medical center in a southern area of China

Pathogens and Disease ◽

10.1093/femspd/ftz034 ◽

2019 ◽

Vol 77 (4) ◽

Cited By ~ 1

Author(s):

Lili Fang ◽

Xiaohui Lu ◽

Heping Xu ◽

Xiaobo Ma ◽

Yilan Chen ◽

...

Keyword(s):

Risk Factors ◽

Medical Center ◽

Academic Medical Center ◽

Pulmonary Diseases ◽

Controlled Study ◽

Global Public Health ◽

Detection Rates ◽

Carbapenem Resistant ◽

Associated Risk Factors ◽

Carbapenem Resistant Enterobacteriaceae

ABSTRACT OBJECTIVE While the emergence and spread of carbapenem-resistant Enterobacteriaceae (CRE) and related infections pose serious threats to global public health, the epidemiology and associated risk factors remain poorly understood and vary by geography. METHODS In a case-controlled retrospective study, we examined the prevalence, patient background and risk factors for CRE colonisation and infections, and all patient-derived CRE from January 2015 to January 2017. Isolated carbapenem-susceptible Enterobacteriaceae (CSE) from 2875 enrolled patients were randomly selected during the study. RESULTS CRE colonisation and infections detection rates were 47/2875 (1.6%). Respiratory tract specimens were most frequently seen in 20/47 (42.6%) cases. Klebsiella pneumoniae was the main isolate in 35/47 (74.5%) CRE. As for carbapenemase, KPC-2-producing bacteria was most frequently detected in 38/47 (80.9%) Enterobacteriaceae. No underlying conditions (P = 0.004), pulmonary diseases (P = 0.018) and no antibiotics used prior to culture within 30 days (P < 0.001) were statistically significant between the CRE and CSE groups. CONCLUSION Klebsiellapneumoniae was the main isolate of CRE. The blaKPC-2 was the predominant CRE gene. Underlying conditions especially pulmonary diseases and antibiotics used prior to culture within 30 days represented key risk factors for acquisition of CRE.

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Evaluation of the Vitek 2, Phoenix and Microscan for Antimicrobial Susceptibility Testing of Stenotrophomonas maltophilia

Journal of Clinical Microbiology ◽

10.1128/jcm.00654-21 ◽

2021 ◽

Author(s):

Ayesha Khan ◽

Cesar A. Arias ◽

April Abbott ◽

Jennifer Dien Bard ◽

Micah M. Bhatti ◽

...

Keyword(s):

Antimicrobial Susceptibility ◽

Stenotrophomonas Maltophilia ◽

Susceptibility Testing ◽

High Rate ◽

Broth Microdilution ◽

Antimicrobial Susceptibility Tests ◽

Microscan Walkaway ◽

Vitek 2 ◽

Susceptibility Tests ◽

Immunocompromised Hosts

Stenotrophomonas maltophilia causes high mortality infections in immunocompromised hosts with limited therapeutic options. Many U.S. laboratories rely on commercial automated antimicrobial susceptibility tests (cASTs) and use CLSI breakpoints (BPs) for S. maltophilia. However, contemporary data on these systems is lacking. We assessed performances of Vitek2, MicroScan Walkaway and Phoenix relative to reference broth microdilution for trimethoprim-sulfamethoxazole (SXT), levofloxacin (LEV), minocycline (MIN) and ceftazidime (CAZ), with 109 S. maltophilia bloodstream isolates. Using CLSI breakpoints, categorical agreement (CA) was below 90% on all systems and drugs, with the exception of SXT by MicroScan (98.1%) and Phoenix (98.1%) and MIN by MicroScan (100%) and Phoenix (99.1%). For SXT, Vitek2 yielded a 77.1% CA. LEV and CAZ CA ranged from 67% - 85%. Very major errors (VME) were >3% for SXT (MicroScan, Phoenix), LEV (MicroScan) and CAZ (all systems). Major errors (ME) were >3% for SXT (Vitek 2), LEV (Phoenix) and CAZ (MicroScan, Phoenix). Minor errors were >10% for CAZ and LEV on all systems. Data were analyzed with EUCAST pharmacokinetic/pharmacodynamic CAZ, LEV, ciprofloxacin (CIP) and tigecycline (TGC) breakpoints when possible. CA was <90% for all. VME were >3% for CAZ (all systems), LEV (MicroScan), and TGC (Vitek2) and ME were >3% for LEV (MicroScan), CAZ (all systems), ciprofloxacin (Vitek2 and MicroScan) and TGC (Vitek 2, Phoenix). Minor errors (MI) were >10% for all agents and systems, by EUCAST breakpoints with an intermediate category (LEV, CAZ, CIP). Laboratories should use caution with cASTs for S. maltophilia as a high rate of errors may be observed.

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Epidemiology of carbapenem-resistant Enterobacteriaceae colonization in ICU: a pilot study from a tertiary care hospital in Western Rajasthan, India

International Journal of Research in Medical Sciences ◽

10.18203/2320-6012.ijrms20184043 ◽

2018 ◽

Vol 6 (10) ◽

pp. 3340 ◽

Cited By ~ 2

Author(s):

Ekadashi Rajni ◽

Vikas Rajpurohit ◽

Praveen Rathore ◽

P. K. Khatri

Keyword(s):

Pilot Study ◽

Large Scale ◽

Tertiary Care Hospital ◽

Tertiary Care ◽

Control Measures ◽

Care Hospital ◽

Beta Lactamase ◽

Global Public Health ◽

Carbapenem Resistant ◽

Carbapenem Resistant Enterobacteriaceae

Background: Carbapenem-resistant Enterobacteriaceae (CRE) is a serious global public health threat. Antibiotic overuse, improper sanitation and unhygienic practices lead to large scale carriage and rapid spread.Methods: This is a prospective hospital based study planned for a period of 3 months including all patients admitted to 14 bedded Trauma ICU of a tertiary care hospital in Rajasthan. Rectal swabs were collected from admitted patients and carriage of carbapenem resistant Enterobacteriaceae looked for as per CDC guidelines. Screening of the Enterobacteriaceae colonies for carbapenemase production was done by Modified Hodge test. Carbapenem-resistant isolates were also tested for Metallo beta lactamase production by phenotypic disc confirmatory test.Results: A total of 73 patients were screened and 27 CRE isolates were obtained, carriage rate being 37%. A high level of resistance was seen to aminoglycosides, fluoroquinolones and cephalosporins. 100% sensitivity was however seen to Colistin, Tigecycline and Fosfomycin. 5 out of 27 strains showed a positive MHT test. Metallo beta lactamase (MBL) production was seen in 21/25 strains as tested by meropenem and Meropenem-EDTA discs.Conclusions: The current pilot study finds out the prevalence of CRE carriage among critically ill patients and stresses upon strong need for stringent infection control measures.

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CARBAPENEM-RESISTANT ENTEROBACTERIACEAE: NEW MENACE TO OUR ANTIBIOTIC ARMAMENTARIUM!

Asian Journal of Pharmaceutical and Clinical Research ◽

10.22159/ajpcr.2017.v10i9.19448 ◽

2017 ◽

Vol 10 (9) ◽

pp. 335

Author(s):

Ankita Porwal ◽

Sevitha Bhat

Keyword(s):

Risk Factors ◽

Polymyxin B ◽

Isolation Rate ◽

Chi Square ◽

Carbapenem Resistant ◽

Chi Square Test ◽

Vitek 2 ◽

The Common ◽

Common Infection ◽

Carbapenem Resistant Enterobacteriaceae

Objective: To study the risk factors, clinical characteristics, and outcome in patients with infections due to CRE infections.Methods: Retrospective study was carried out in a microbiology laboratory for 6 months. 152 CRE isolates identified by the Vitek 2 compact system were included in the study. The risk factors, antibiotic treatment and clinical outcome were studied from the case sheets, Chi-square test was used for statistical analysis.Results: Of the 2520 positive cultures for Enterobacteriaceae, isolation rate of CRE was 152 (6%). 76 (50%) belonged to exudates, 22 (14.1%) blood culture, 90 (59.2%) urine. The common infection was UTI. The risk factors were prior exposure to antimicrobials, admission to intensive care unit, indwelling devices and prior hospitalization. The effective antibiotic was colistin, polymyxin B, tigecycline, cefoperazone-sulbactum, piperacillin-tazobactum. The mortality was 19.7%.Conclusion: We have demonstrated the value of understanding local epidemiology to help modify our risk-based screening as a strategy to limit the spread of CRE.

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What are acute NHS trusts in England doing to prevent the cross-border spread of carbapenem-resistant Enterobacteriaceae?

Journal of Infection Prevention ◽

10.1177/1757177420935633 ◽

2020 ◽

Vol 21 (5) ◽

pp. 196-201

Author(s):

Sharon Mawdsley

Keyword(s):

Public Health ◽

Global Public Health ◽

Cross Border ◽

Carbapenem Resistant ◽

Screening Protocol ◽

Mandatory Participation ◽

The Cross ◽

The Uk ◽

Healthcare Associated ◽

Carbapenem Resistant Enterobacteriaceae

Background: Carbapenem-resistant Enterobacteriaceae (CRE) pose a significant threat to global public health as these organisms have the potential to cause infections which are easily spread and are associated with high mortality rates. Aim/Objective: The aim of this study was to establish which screening strategies acute NHS trusts in England have chosen to adopt and whether or not that strategy has prevented or is likely to prevent the cross-border spread of CRE. Methods: All acute NHS trusts in England were invited to participate in a multicentre quantitative study. Participants were asked to complete a questionnaire relating to their local CRE screening protocol. Findings/Results: Of the 91 participating trusts, 83 (91.2%) adhere to Public Health England (2013) guidance. However, only 22 (24.2%) trusts have adopted the European Centre for Disease Prevention and Control (2016) recommendations. In total, 31 (34.1%) trusts reported incidences of person-to-person transmission, of which 45.2% were related to foreign travel. Furthermore, 31 (34.1%) trusts reported that patients who have had an admission to a hospital in the UK not known to have a high prevalence of healthcare-associated CRE in the last 12 months had screened positive. Discussion: This study has demonstrated that inter-hospital transmission is as much of a concern as cross-border spread. Mandatory participation in enhanced surveillance could provide PHE with the epidemiological evidence required to support this stance and help to develop new national guidance.

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Treatment Options for Carbapenem-Resistant Enterobacteriaceae Infections

Open Forum Infectious Diseases ◽

10.1093/ofid/ofv050 ◽

2015 ◽

Vol 2 (2) ◽

Cited By ~ 184

Author(s):

Haley J. Morrill ◽

Jason M. Pogue ◽

Keith S. Kaye ◽

Kerry L. LaPlante

Keyword(s):

Treatment Options ◽

Treatment Strategies ◽

Current Treatment ◽

Additional Treatment ◽

Global Public Health ◽

Carbapenem Resistant ◽

Dosing Regimens ◽

Poor Outcomes ◽

Enterobacteriaceae Infections ◽

Carbapenem Resistant Enterobacteriaceae

Abstract This article provides a comprehensive review of currently available treatment options for infections due to carbapenem-resistant Enterobacteriaceae (CRE). Antimicrobial resistance in Gram-negative bacteria is an emerging and serious global public health threat. Carbapenems have been used as the “last-line” treatment for infections caused by resistant Enterobacteriaceae, including those producing extended spectrum ß-lactamases. However, Enterobacteriaceae that produce carbapenemases, which are enzymes that deactivate carbapenems and most other ß-lactam antibiotics, have emerged and are increasingly being reported worldwide. Despite this increasing burden, the most optimal treatment for CRE infections is largely unknown. For the few remaining available treatment options, there are limited efficacy data to support their role in therapy. Nevertheless, current treatment options include the use of older agents, such as polymyxins, fosfomycin, and aminoglycosides, which have been rarely used due to efficacy and/or toxicity concerns. Optimization of dosing regimens and combination therapy are additional treatment strategies being explored. Carbapenem-resistant Enterobacteriaceae infections are associated with poor outcomes and high mortality. Continued research is critically needed to determine the most appropriate treatment.

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