Epidemiology and Clonal Spread Evidence of Carbapenem-Resistant Organisms in the Center of Care and Protection of Orphaned Children, Vietnam

Objective: To determine the prevalence of colonization and transmission of carbapenem-resistant Gram-negative organisms in order to develop of an effective infection prevention program. Design: Cross-sectional study with carbapenem-resistant organisms (CRO) colonization detection from the fecal specimens of 20 Health Care Workers (HCWs) and 67 residents and 175 random environment specimens from September 2022 to September 2023. Setting: A Care and Protection Centre of Orphaned Children in South of HCM City. Participants: It included 20 HCWs, 67 residents, and 175 randomly collected environmental specimens. Method: Rectal and environmental swabs were collected from 20 HCWs, 67 residents (most of them were children), and 175 environmental specimens. MELAB Chromogenic CARBA agar plates, Card NID, and NMIC-500 CPO of the BD Phoenix TM Automated Microbiology System and whole genome sequencing (WGS) were the tests to screen, confirm CROs, respectively and determine CRO colonization and transmission between HCWs, residents, and the environment. Result: We detected 36 CRO isolates, including 6, 11 and 19 CROs found in 6 HCWs, 10 residents and 19 environments. The prevalence of detectable CRO was 30% (6/20) in HCWs, 14.92% (10/67) in residents, and 10.86% (19/175) in environmental swabs in our study. WGS demonstrated CRO colonization and transmission with the clonal spread of E. coli and A. nosocomialis, among HCWs and residents (children). Conclusion: Significant CRO colonization and transmission was evident in HCWs, residents, and the center environment. Cleaning and disinfection of the environment and performing regular hand hygiene are priorities to reduce the risk of CRO colonization and transmission.

Risk of transmission of carbapenem-resistant Enterobacteriaceae and related “superbugs” during gastrointestinal endoscopy

To evaluate the risk of transmission of carbapenem-resistant Enterobacteriaceae(CRE) and their related superbugs during gastrointestinal(GI) endoscopy. Reports of outbreaks linked to GI endoscopes contami-nated with different types of infectious agents, includ-ing CRE and their related superbugs, were reviewed. Published during the past 30 years, both prior to and since CRE's emergence, these reports were obtained by searching the peer-reviewed medical literature(via the United States National Library of Medicine's "MEDLINE" database); the Food and Drug Administration's Manu-facturer and User Facility Device Experience database, or "MAUDE"; and the Internet(via Google's search engine). This review focused on an outbreak of CRE in 2013 following the GI endoscopic procedure known as endoscopic retrograde cholangiopancreatography, or ERCP, performed at "Hospital X" located in the sub-urbs of Chicago(IL; United States). Part of the largest outbreak of CRE in United States history, the infection and colonization of 10 and 28 of this hospital's patients, respectively, received considerable media attention and was also investigated by the Centers for Disease Con-trol and Prevention(CDC), which published a report about this outbreak in Morbidity and Mortality WeeklyReport(MMWR), in 2014. This report, along with the results of an independent inspection of Hospital X's in-fection control practices following this CRE outbreak, were also reviewed. While this article focuses primar-ily on the prevention of transmissions of CRE and their related superbugs in the GI endoscopic setting, some of its discussion and recommendations may also apply to other healthcare settings, to other types of flexible endoscopes, and to other types of transmissible infec-tious agents. This review found that GI endoscopy is an important risk factor for the transmission of CRE and their related superbugs, having been recently as-sociated with patient morbidity and mortality following ERCP. The CDC reported in MMWR that the type of GI endoscope, known as an ERCP endoscope, that Hospi-tal X used to perform ERCP in 2013 on the 38 patients who became infected or colonized with CRE might be particularly challenging to clean and disinfect, because of the complexity of its physical design. If performed in strict accordance with the endoscope manufacturer's labeling, supplemented as needed with professional organizations' published guidelines, however, current practices for reprocessing GI endoscopes, which include high-level disinfection, are reportedly adequate for the prevention of transmission of CRE and their related superbugs. Several recommendations are provided to prevent CRE transmissions in the healthcare setting. CRE transmissions are not limited to contaminated GI endoscopes and also have been linked to other reusable flexible endoscopic instrumentation, including broncho-scopes and cystoscopes. In conclusion, contaminated GI endoscopes, particularly those used during ERCP, have been causally linked to outbreaks of CRE and their related superbugs, with associated patient morbidity and mortality. Thorough reprocessing of these complex reusable instruments is necessary to prevent disease transmission and ensure patient safety during GI endos-copy. Enhanced training and monitoring of reprocessing staffers to verify the proper cleaning and brushing of GI endoscopes, especially the area around, behind andnear the forceps elevator located at the distal end othe ERCP endoscope, are recommended. If the ERCPendoscope features a narrow and exposed channel thathouses a wire connecting the GI endoscope's controhead to this forceps elevator, then this channel's com-plete reprocessing, including its flushing with a deter-gent using a procedure validated for effectiveness, is also emphasized.

Treatment of sepsis: What is the antibiotic choice in bacteremia due to carbapenem resistant Enterobacteriaceae?

Sepsis is one of the major challenges of today. Although gram-positive bacteria related infections are more prevalent in hospital setting, the highest mortality rate is associated with gram-negative microorganisms especially Enterobacteriaceae. Enterobacteriaceae, including Escherichia coli, Klebsiella spp., Proteus spp., Enterobacter spp. and Serratia spp. Resistance to β-lactams in Enterobacteriaceae is primarily attributed to the production of B-lactamase enzymes with subsequent antibiotic hydrolysis and to a lesser extent by alteration of efflux pump or porins expression. Carbapenem resistant Enterobacteriaceae(CRE) and Acinetobacter baumannii are the most notorious pathogens due to the high incidence of morbidity and mortality especially in the immunocompromised patients in the intensive care unit. The most appropriate antimicrobial therapy to treat CRE is still controversial. Combination therapy is preferred over monotherapy due to its broad-spectrum coverage of micro-organisms, due to its synergetic effect and to prevent development of further resistance. Current suggested therapies for CRE resistance as well as promising antibiotics that are currently under investigation for winning the war against the emerging CRE resistance are reviewed and discussed.

Phenotypic Characterization of Carbapenemase-Producing Enterobacteriaceae Strains in a Referral Teaching Hospital in Yaoundé, Cameroon

Background: Carbapenemase-producing Enterobacteriaceae (CPE) are an important and increasing threat to global health. They are nowadays more encountered routinely in hospitals and cause high morbidity and mortality due to limited therapeutic alternatives. This study sought to determine the prevalence of CPE in Yaoundé teaching hospital, Cameroon, and the associated risk factors. Materials and Method: To achieve this goal, a descriptive cross-sectional study coupled to an analytical component with consecutive collection of Enterobacteria strains was carried out during a three-month period (from 27th July to 24th October 2018) in the University Teaching Hospital of Yaoundé, Cameroon. The oxidase and biochemical identification tests using a miniaturized Api 20 E system were performed on colonies grown on Eosin Methylene Blue (EMB) medium and subcultured on nutrient agar. Drug susceptibility testing was carried out according to the Antibiogram Committee of the French Society of Microbiology (CA-SFM 2018.V.2.0). The detection of carbapenemase production was performed by the CA-SFM 2018 algorithm for the screening of carbapenemase-producing enterobacteriaceae and its classification by inhibitory synergy tests. Results: Out of the 104 isolates, Escherichia coli (50%) was the most prevalent species, followed by Klebsiella pneumoniae (37.5%) and Citrobacter frendii (12.5%). Drugs susceptibility patterns showed a high resistance to penicillins group (97.4% to amoxicillin), cephalosporins (68.4% to cefotaxim, 58.1% to cefixim, 60.7% to ceftazidim, 57.1% of cefoxitin) and aztreonam (55.7%). However, 11.9% carbapenems related resistance was noticed: 14.4% to imipenem, 13.8% to ertapenem and 7.5% to meropenem. Numerous co-resistance to quinolones (65.8%), fluoroquinolones (49.6%), aminoglycosides (49.6%) and cotrimoxazole (71.8%) were also observed. From 104 isolates, AmpC production represented 23.08% (25/104) and 36.54% (38/104) were ESBL-isolates. The overall prevalence of CPE was 25% (26/104) with K.pneumoniae predominant (61.53%). Besides, Class A and class B carbapenemase were mainly produced with respectively 20% (21/104) and 5% (5/104). Univariate analysis revealed a significant association of carbapenemase production to Klebsiella pneumoniae (p = 0.01), ESBL and AmpC production ((P = 0.01 and P = 0.001 respectively) while that association was only significant to Klebsiella spp (p = 0.04) and AmpC production (p = 0.02) in multivariate analysis. Conclusion: The multi-resistance of Enterobacteriaceae to antibiotics in Cameroon has considerably increased. More attention should be paid to those bacteria to stall antimicrobial resistance spread.

Risk Factors and Prevalence of Mother to New-Born Transmission of Carbapenemase Producing Enterobacteriaceae in Two Hospitals in Yaounde, Cameroon

Background: In African countries, where the burden of neonatal sepsis is the highest, the spread of Carbapenemases Producing Enterobacteriaceae (CPE) in the community, potentially contributing to neonatal mortality, is a public health concern. The transmission routes are not well defined, particularly the possible key role played by pregnant women. The aim of this study was to understand the neonatal acquisition of CPE in Yaounde, Cameroon. Methods: A transversal analytical study was conducted in an urban area. Maternal stool samples during delivery and the first stool from their new-born were collected and cultured to isolate Enterobacteria. After isolation, characterization using API20E identification system, and antibiotic susceptibility testing were performed according to the Antibiogram Committee of the French Society of Microbiology. Carbapenemases detection was done on each carbapenem-resistant strain using the Modified Hodge Test (MHT) and their classification using the synergy tests with different inhibitors. Results: Out of the 55 CPE isolates identified, Escherichia coli was the most encountered bacteria both in mothers (n = 18, 50.00%) and infants (n = 11, 57.89%). Class B and D carbapenemases were found both in mothers and infants. The estimated prevalence of vertical transmission in our study, was 10% (n = 12). Logistic regression showed that CPE carriage in mothers and CPE acquisition in their new-borns were independently associated with the presence of greenish amniotic fluid (OR = 7.33, p 0.0001 in mothers and OR = 4.09, p = 0.0086 in new-borns). Conclusion: Our results highlight the non-negligeable role played by pregnant women in the neonatal acquisition of CPE.

Genotypic Diversity and Characterization of Quinolone Resistant Determinants from Enterobacteriaceae in Yaoundé, Cameroon

Background: Enterobacteriaceae causes many types of infections which are often treated with quinolones and fluoroquinolone (Q/FQ). The resistance mechanisms to Q/FQ are usually associated with mutations in the quinolone resistance determining region which alter the conformation of target amino acid residues within the protein and in the qnr genes. This study aimed at determining the antimicrobial resistant profile of a sample of Enterobacteriaceae from Cameroon and the genetic diversity in quinolone-resistant isolates in view of implementing a better management, treatment, control and prevention of the transmission of these resistant strains. Methods: Identification and antimicrobial susceptibility testing was done using VITEK 2. The detection of plamid-mediated quinolone resistance (PMQR) genes was carried out using the conventional PCR method. Sequencing was done using the Applied Biosystem 3500 genetic analyser. DNA fingerprint was obtained using Pulsed-Field Gel electrophoresis. Results: Among 440 Enterobacteriaceae, the most prevalent genera were: Escherichia 178/440 (39.5%);Klebsiella 148/440 (33.6%);Enterobacter 35/440 (8%);Pantoea 28/440 (6.4%);Proteus 14/440 (3.2%) Salmonella 13/440 (3%). Ampicillin resistance showed the highest prevalence with 371/440 (81%) and Imipenem the lowest resistance 9/440 (2.1%). The ciprofloxacin resistance rate was 161/440 (36.6%). The detected plasmid mediated quinolone resistance (PMQR) genes were: qnrA, 2/161 (1.2%);qnrB, 31/161 (19.3%);qnrS, 13/161 (8.1%): Aac (6')Ib-cr, 84/161 (52.2%) and qepA, 3/161 (1.9%). There were several mutations in the parC gene of Klebsiella leading to S80D and S80N substitutions. Two pairs of Klebsiella peumoniae strains were phenotypically and genotypically identical with 100% similarity in the dendrogramme. Conclusion: This study showed that quinolone resistance was high. The PMQR genes contributing to this resistance were diverse. This high PMQR indicates that there has been an unknown circulation of these genes in our community. To avoid the rapid dissemination of these PMQR genes continuous surveillance of antimicrobial resistance should be carried out not only in humans but also in animals to monitor the evolution of these genes.

Prevalence of Carbapenem-Resistant Klebsiella Pneumoniae （CRKP） and the Distribution of Class 1 Integron in Their Strains Isolated from a Hospital in Central China

Objective The aim of our study is to investigate the prevalence of Carbapenem-resistant Klebsiella pneumoniae （CRKP） and the genetic characteristics of the class 1 integron in CRKP on multi-drug resistance. Methods Clinical Klebsiella pneumoniae strains were collected from multiple departments of a hospital in central China. CRKP strains were identified among the isolates, and antibiotics susceptibility of CRKP strains was analyzed. The polymerase chain reaction （PCR） was adopted to amplify the class 1 integron variable area. The integron genetic structure was analyzed with enzyme digestion and DNA sequencing technology. The relation between class 1 integron and drug resistance was analyzed statistically. Results Totally 955 strains of Klebsiella pneumoniae were isolated from varied sites of the hospital, and 117（12.3%） of them were identified as CRKP, with a separation rate of 8.9% （26/292） in 2013, 11.3% （38/336） in 2014 and 16.2% （53/327） in 2015, which shows an increasing trend by year. 44.4% （52/117） of CRKP strains were separated from specimen of ICU, and 61.5% （72/117） were from sputum. Over 95% CRKP strains were resistant to ampicillin/sulbactam, aztreonam, imipenem, meropenem Ceftazidme,Cefotaxime,Cefepime,and Piperacillin, while relatively low resistant rates were found in Tigecycline （12.8%） and colistin （35.9%）. The class 1 integron was detected in 77.8% （91/117） of CRKP strains. Class 1 integron of CRKP was significantly correlated with the antibiotic resistance to the tobramycin, gentamicin and amikacin （all P〈0.01）. The gene cassette analysis of variable area of class 1 integron showed that aadA2 accounts for 64.8% （59/91）, aacA4-catB8-aadA1 23.1% （21/91）, and aadA2-dfrA25 12.1% （11/91）. Conclusions CRKP has an increasing trend in a clinical setting in China, and most of them were resistant to multiple antibiotics. Class 1 integron in CRKP has strong ability to capture the genes resistant to aminoglycosides antibiotics from environment, with the aadA2 gene as the most popular one.

Patient Demographics and Characteristics of Infection with Carbapenem-Resistant <i>Acinetobacter baumannii</i>in a Teaching Hospital from the United States

A characterization of the clinical demographic features of patients with infection caused Acinetobacter baumannii, and the antibiotyping of the isolates recovered from these patients was undertaken, with a special reference to carbapenem-resistant variants, and their risk factors. This study was conducted retrospectively from January 2010 to March 2011 at a 616-bed tertiary care university hospital. Sixty-four patients were identified. Clinical and microbiological data were analyzed for risk factors and demographic features to derive relative risk and odds ratio. We identified 100 A. baumannii from 64 patients during 15 months period. Significant risk factors were working age (18 - 60 years), male gender, hospital stay (>1 week but Pseudomonas aeruginosa, and Klebsiella pneumoniae were the significant co-infecting agents. The antibiogram demonstrated multidrug resistance in a majority of the isolates. Relative risk associated with ventilator, diabetes, and surgery was higher in repeat isolates than in first isolates and were multidrug resistant. Repeat isolates were more resistant that the first isolates to most anti-acinetobacter agents, but the overall crude mortality was not significant during this study period, and couldn’t correlated to the choice of treatment. In conclusion, a resistance against all clinically used carbapenems, and colistin is rapidly increasing in repeat isolates of A. baumannii;leaves narrow therapeutic options to treat multidrug-resistant and pandrug-resistant A. baumannii infection. For the first time we report rising incidence of colistin resistance by 20 percent in repeat isolates, and is worrisome for healthcare centers. A combination therapy should be adopted to treat such infection to avoid the emergence of colistin-resistant phenotypes in the United States.

Antimicrobial Resistance among Enterobacteriaceae Found in Chicken and Cow Droppings and Their Public Health Importance

Introduction: The recent surge in the number of antimicrobial resistant cases from hospitals and communities has created a need to study the points and sources of exposure to certain bacteria and determine their susceptibility to commonly used antibiotics. This study aimed at identifying and screening for drug-resistant Enterobacteriaceae isolated from chicken droppings and cow dungs in Onitsha, Anambra state, in the South-Eastern part of Nigeria. Methods: This is a cross-sectional descriptive study which included 50 chickens and 50 cow dung samples collected from five poultry houses and cow ranches respectively using sterile swab sticks. The samples were transported to the laboratory and processed following standard microbiological protocols. Isolates in the samples were recovered using MacConkey Agar, Eosin Methylene Blue Agar and Salmonella-Shigella Agar following standard microbiological procedures and then identified/characterized biochemically using commercial API 20E identification kits following the standard manufacturer’s protocol. Isolates were subjected to antibiotic susceptibility testing on Muller Hinton Agar using Kirby Bauer double-disc diffusion technique. The multiple antibiotics resistance index was determined as well. Isolates with reduced susceptibility to Ceftazidime were screened for extended spectrum beta-lactamase, AmpC- and metallo-beta-lactamase-production using Rosco Diagnostic kit. Results: Sixty-two (100%) Gram-negative bacteria were isolated from a total of 100 samples collected from both sites, out of which 43 (69.4%) are Enterobacteriaceae. A total of 30/43 (69.8%) Enterobacteriaceae including K. pneumoniae, S. enteritica, S. odorifera, E. coli, K. intermediate, P. stuartii, E. aerogenes, P. penneri, P. mirabilis and C. braakii were recovered from chicken droppings, whereas 13/43 (30.2%) Enterobacteriaceae including K. pneumoniae, S. enteritica, S. odorifera, E. coli, K. intermediate, P. stuartii, E. aerogenes, P. penneri, P. mirabilis and C. braakii were recovered from cow dungs. Two (12.5%) different isolates demonstrated metallo-beta-lactamase and cephalosporinase (AmpC) production. The isolates were susceptible to six antibiotics tested except Augmentin and Nitrofurantoin where the resistance is 100% and 85% respectively while Ceftriaxone and Ofloxacin had the best antibacterial activity against the isolates from both sites. Conclusion: The bacteria of public health importance isolated from these sites and their antibiogram profile have shown the need for proper monitoring and management of animal wastes in order to mitigate the threat to human health in the spirit of One Health as well as contribute to the fight against antibiotic resistance.

Trends in the Annual Incidence of Carbapenem Resistant among Gram Negative Bacilli in a Large Teaching Hospital in Makah City, Saudi Arabia

Objective: To detect the prevalence of carbapenem resistance among Gram negative bacilli at the Al-Noor Specialist Hospital in the western part of Saudi Arabia. Materials and Methods: This study was conducted in the Microbiology department, Al-Noor Specialist Hospital, Makah city, Saudi Arabia. The clinical samples were collected from admitted patients in the wards, Intensive Care Units (ICUs), urology unit and surgery unit, these samples included blood, urine, sputum, pus and wound. The identification and antibiotic susceptibility testing of all bacterial isolates were performed via the Vitek 2 Compact System. Results: Out of 4803 Gram negative bacterial bacilli were isolated, the prevalence rate of carbapenem resistance among these isolates was 2797/4803 (58.23%), and sensitivity rate was 2006/4803 (41.77%) of the total isolates. The rate of resistance to carbapenem was among Acinetobacter baumannii 1710 (99.13%), followed by Pseudomonas aeruginosa 575 (62.4%), Klebsiella pneumoniae 459 (38%) and Escherichia coli 56 (5.59%). The trend of carbapenem resistance among Gram negative bacterial isolates from 2013-2015 was 53.99%, 59.88% and 61.43% respectively. Conclusion: A. baumannii rec-orded, the highest rate of carbapenem resistance through three year, 98.19%, 99.48% and 99.81% respectively and the lowest rate of resistance recorded with E. coli, 4.63%, 5.79% and 6.31% respectively.

A Case of Carbapenem Resistant Non-K1/K2 Serotype <i>Klebsiella pneumoniae</i>Liver Abscess

Klebsiella pneumoniae liver abscess (KPLA) has been described as an invasive syndrome with extrahepatic complications. The majority of KPLA is caused by capsular serotype K1 and K2 isolates. We report a case of carbapenem resistant Klebsiella pneumoniae liver abscess. The patient initially presented with infected right above-the-knee amputation and was later found with a large liver abscess. Initial antimicrobial susceptibility showed carbapenem resistant K. pneumoniae (CRKP). Further molecular workup revealed that the isolate was a less virulent non-K1/K2 serotype, and both rmpA and kfu genes were negative. The lack of outer membrane porins likely contributed to the carbapenem resistance. To our knowledge, this is a first reported case of carbapenem resistant, non-K1/K2 serotype K. pneumoniae liver abscess in the United States.

Study of OmpK35 and OmpK36 Expression in Carbapenem Resistant ESBL Producing Clinical Isolates of Klebsiella pneumoniae

Background: Carbapenem resistant extended spectrum β-lactamase (ESBL) producing Klebsiella pneumoniae (K. pneumoniae) is increasing worldwide. Carbapenem resistance (CR) has been attributed not only to production of carbapenemases but also to permeability barriers due to outer membrane proteins (OmpK35 and OmpK36) disruption. Objective: Phenotypic detection of CR among ESBL producing K. pneumoniae isolates, followed by the evaluation of the role of ompK35 and ompK36 gene expression among carbapenem resistant K. pneumoniae (CR-KP) isolates. Methods: 100 ESBL producing K. pneumoniae isolates were included in this study. Minimum inhibitory concentration (MIC) of imipenem was performed for all isolates by broth microdilution method. For CR-KP isolates, phenotypic detection of K. pneumoniae carbapenemase (KPC), metallo-β-lactamase (MBL) and AmpC enzymes was performed followed by Realtime qRT-PCR to detect and quantify ompK35 and ompK36 gene expression. Results: 42% of our isolates were carbapenem resistant, and all of them were KPC producers either singly or in combination with MBL and/or AmpC production. Reduced expression of both ompK35 and ompK36 was detected in (52.38%) of CR-KP isolates, while reduced expression of ompK36 or ompK35 alone was found in (2.38%) and (33.33%) respectively. Twenty of 42 CR-KP isolates (47.62%), showing reduced ompK35 and ompK36 expression, exhibited high level resistance (HLR) (>32 μg/ml) to imipenem. There was a significant correlation between reduced expression of ompK36 and increase MIC values (p < 0.05). The combined production of MBL or AmpC together with reduced expression of ompK35 and/or ompK36 resulted in significant increase in imipenem MIC (p < 0.05). Conclusion: The combined OmpK35/OmpK36 loss resulted in HLR. However OmpK36 seems to play a major role in those strains. Imipenem MIC was markedly increased among K. pneumoniae showing carbapenemase and/or AmpC production together with loss of OmpK35 and/or OmpK36.

Molecular Detection of Carbapenemase Genes in Extensive Drug Resistant Acinetobacter baumannii Clinical Isolates from ICU Patients, Khartoum

Background: The emergence of carbapenemase producing Acinetobacter baumannii is increasingly reported nowadays and constitutes a major problem to the intensive care unit (ICU) patients with notable extensive-drug resistance ability. The study investigates carbapenemase producing A. baumannii strains exhibiting an extensively drug-resistant (XDR) phenotype, isolated from ICU patients in Khartoum. Methods: A total of 100 nonduplicate Gram-negative coccobacilli strains were obtained from microbiology laboratory of ICU patients’ clinical isolates. Molecular identification of A. baumannii was performed by targeting 16S rRNA gene using specifically designed primers. Then, XDR strains were determined by susceptibility testing (disc diffusion). For detection of carbapenemase genes Polymerase chain reaction (PCR) was carried out. Result: Of 100 ICU clinical isolates, 38 (38.0%) was confirmed A. baumannii strains, those strains showed 100% carbapenem resistance and 60.5% extensive drug resistance to the antibiotics tested. The frequency of carbapenemase producer was 57.9% (22/38) of carbapenem resistance A. baumannii (CRAB). The most common carbapenemase associated with resistance was blaOXA gene followed by blaNDM and blaGES A. baumannii isolates. The co-occurrence of blaOXA-48-like and blaNDM, blaOXA-23-like and blaOXA-51, and blaNDM-1 and blaOXA-51 was detected in 22.7%, 18.2% strains and 4.5% respectively. A unique characteristic of our findings was the coharbouring of the genes blaNDM-1, blaOXA-23-like, blaOXA-51 and blaOXA-143 in 9.1% strains (2/22), and this was the first report in the Khartoum city, Sudan. Conclusion: We have demonstrated for the first time a high prevalence of XDR-carbapenemase producing A. baumannii clinical isolates from ICU patients in Khartoum. Also an emergent blaOXA-143 was reported as High-Risk Clones. This highlights the routine mentoring of XDR-carbapenemase producing A. baumannii to avoid clone dissemination in our region hospitals.

In Vitro Antibacterial Activity of Galla Chinensis Combined with Different Antibacterial Drugs against Carbapenem-Resistant E.Coli

Objective:To evaluate the antibacterial effects of meropenem and levofloxacin respectively combined with Galla chinensis on carbapenem-resistant Escherichia coli in vitro.Methods:The protocol was designed with checkerboard method and the carbapenem-resistant E.coli was isolated in our hospital.The minimum inhibitory concentrations(MICs)of G.chinensis alone and combined with 2 antimicrobial agents against carbapenem-resistant E.coli were determined by broth dilution method and the fractional inhibitory concentration index(FICI)was calculated according to MICs results.Result:the combined use of G.chinensis and meropenem(or levofloxacin)significantly decreased both MIC50 and MIC90;After the combination of G.chinensis and meropenem,the synergistic effect was 86.7%,and the additive effect was 13.3%,no irrelevant and antagonistic effects.After combined use of G.chinensis and levofloxacin,the synergistic effect was 66.7%,and the additive effect was 33.3%.No irrelevant and antagonistic effects.Conclusion:Galla chinensis combined with meropenem or levofloxacin has synergistic and additive antibacterial effect,with certain combined antibacterial activity.

bla_(CTX-M),bla_(TEM),and bla_(SHV) in Enterobacteriaceae from North-Indian tertiary hospital:high occurrence of combination genes

Objective:To delineate the frequency of occurrence of bla_(CTX-M),bla_(TEM),and bla_(SHV) in Enterobacteriaceae from North-Indian tertiary hospital.Methods:A random collection of a subset of 45 Escherichia coli(E.coli) and 28 Klebsiella pneumoniae(K.pneumoniae) that was resistant to a third generation cephalosporin and obtained during 2007-2008 was selected for detailed screening for bla_(CTX-M),bla_(TEM),and bla_(SHV) by monoplex PCRs.The isolates demonstrating the presence of bla_(CTX-M) alleles were characterized for the specific CTX-M-genogroup by using a multiplex PCR.Results:Resistance to cefoperazone,ceftazidime,ceftriaxone,cefotaxime, cefoxitin and piperacillin was 100%each in K.pneumoniae isolates,whereas these resistancerates for E.coli isolates were 93.1%,83.8%,91.9%,93.6%,97.3%and 97.1%,respectively. Concomitant resistance to aminoglycosides,quinolones and aztreonam was also noticed.Presence of any of the bla genes(bla_(CTX-M),bla_(TEM),and bla_(SHV)) was noticed in a total of 28(38.4%) isolates of the 73 isolates studied.Many isolates demonstrated occurrence of these genes in various combinations.bla_(CTX-M),bla_(TEM),and bla_(SHV) were noticed in 28.8%,10.9%and 13.7%isolates, respectively.Multiplex PCR in bla_(CTX-M) harboring isolates demonstrated the presence of CTX-MGenogroup -1 and sequencing for the specific CTX-M-type revealed presence of CTX-M-15 type. RAPD typing showed wide diversity in isolates.Conclusions:This is amongst the premier report describing the simultaneous occurrence of blo_(TEM),bla_(SHV),and bla_(ampC) in Indian Enterobacteriaceae and that wider dissemination of these genes,as demonstrated by diversity of isolates,raises concern and emphasizes a need for extensive search for the presence of these gene pools in Indian subcontinent.

Transmission of Carbapenem Resistance Between Human and Animal NDM-Positive Escherichia coli Strains

Although carbapenem use is prohibited in animals in China,carbapenem-resistant Escherichia coli(CREC),especially New Delhi metallo-β-lactamase(NDM)-producing strains,are widely prevalent in foodproducing animals.At present,the impact of livestock-associated CREC strains on human populations at the national level is unknown.Here,we conduct a retrospective cross-sectional study to investigate the prevalence of CREC from clinical settings across 22 Chinese provinces or municipalities and analyze anthropogenic factors associated with their presence.We also ascertain the blaNDMand blaKPCabundance among pig and chicken farms and present a detailed genomic framework for CREC of animal and human origin.Overall,631/29799(2.1%)clinical Escherichia coli(E.coli)isolates were identified as CREC.Multivariable analysis revealed that being male,an age below 1,an age between 13 and 18,provinces with greater chicken production,and provinces with higher pig production were associated with higher odds of CREC infection.In general,73.8%(n=45/61)of pig farms and 62.2%(n=28/45)of chicken farms had a blaNDMabundance of 1×10^(-5)to 1×10^(-3)and 1×10^(-3)to 1×10^(-2),respectively.Among all the Chinese NDM-positive E.coli(n=463)available at the National Center for Biotechnology Information(NCBI),the genomic analysis revealed that blaNDM-5and Inc X3 were the predominant carbapenemase gene-plasmid combination,while a highly homogeneous relationship between NDM-positive isolates from humans and animals was demonstrated at the plasmid and core genome levels.All the findings suggest frequent CREC transmission between humans and animals,indicating that further discussions on the use of antibiotics in animals and humans are needed,both in China and across the globe.

Low Prevalence of Carbapenem Resistance in Clinical Isolates of Extended Spectrum Beta Lactamase (ESBL) Producing <i>Escherichia coli</i>in North Central, Nigeria

Extended Spectrum Beta Lactamase (ESBL) producing Escherichia coli is a global cause of life threatening infections. We determined the presence of ESBL and carbapenemase production in clinical isolates of E. coli and their antibiotic susceptibility. Clinical isolates of community and hospital acquired E. coli from 220 patients seen at a tertiary hospital were evaluated. Antibiotic susceptibility testing was by the modified Kirby-Bauer protocol while ESBL production was determined by the Double Disk Synergy Test (DDST). Carbapenem resistance was confirmed by the Modified Hodge Test. Of the 220 isolates, 122 (55.5%) were from females;41 (18.6%) were ESBL positive. About 90% of the ESBL producing isolates were resistant to nine of the 15 antimicrobial agents tested. However, only one (2.4%) of the 41 ESBL producing isolates exhibited carbapenem resistance. The ESBL negative isolates were susceptible to Meropenem (100%), Cefepime (97.8%), Ceftriaxone (96.6%) and Cefotaxime (96.6%). All the ESBL producing isolates harbored detectable plasmids with sizes ranging from 2322 to 23,130 base pairs. Our findings show that although multidrug resistant ESBL producing E. coli are prevalent in both the hospital and the community in this environment, carbapenem resistance is still low. We recommend that institutions develop guidelines for the early phenotypic detection of ESBLs and carbapenem resistance.

Antibiotic Resistance in the Uropathogenic Enterobacteria Isolated from Patients Attending General Reference Hospital (GRH) of Niamey, Niger

Background: Urinary tract infections (UTIs) are a frequent reason for consultation and lead to a significant and sometimes inappropriate prescription of antibiotics. The latter favors antibiotic resistance and an increase in mortality as well as the cost of treatment. The present study aims to contribute to the fight against antibiotic resistance of enterobacteria. Methods: This is a prospective study from January to December, 2021 in the Microbiology laboratory of the General Reference Hospital (GRH) of Niamey including 3369 urine samples. The antibiotic resistance of enterobacteria was determined using the Viteck-2 method. Results: At least 280 strains of Enterobacteriaceae were isolated from the patient’s urine. Among these strains, Escherichia coli was the most predominant (74.64%), followed by Klebsiella pneumoniae (16.07%) and Enterobacter cloacae (7.14%) and other enterobacteria 2.15%. These Enterobacteriaceae are more common in community patients than in hospitalized patients. The average age of patients is 52 years and the age group most affected by these enterobacteria is 46 - 60 years (23.33%). The female sex is the most affected sex with (51.07%) against (48.97%) for the male sex with 1.04 as sex ratio. The hospitalization departments most affected by these enterobacteria are Nephrology (29.23%) and Endocrinology (21.54%). Up to 75% of the Enterobacteriaceae isolates show high resistance to ampicillin, amoxicillin-clavulanic acid, ticarcillin, piperacillin-tazobactam, cefoxitin, cefixime, ceftazidime, ceftriaxone, cotrimoxazole, nalidixic acid and ofloxacin. Conclusion: The high rate of antibiotic resistance among enterobacteria in urine is of concern. Only a few Enterobacteriaceae show low resistance to ertapenem, imipenem, amikacin, gentamicin, fosfomycin and nitrofurantoin. Therefore, these antibiotics are recommended as first line treatment for urinary tract infections.

医院获得性耐碳青霉烯类肠杆菌目细菌血流感染危险因素

目的分析医院获得性耐碳青霉烯类肠杆菌目细菌(CRE)血流感染的特点及影响因素。方法采用回顾性巢式病例对照研究方法,选取2020年1月—2022年12月某三级综合医院发生医院获得性CRE血流感染的56例病例为CRE组,按1∶1选择同期56例碳青霉烯类敏感肠菌目细菌(CSE)血流感染患者为CSE组,分析感染菌株和科室分布,并通过单因素和多因素logistic回归分析CRE血流感染的相关因素。结果CRE血流感染科室分布以重症监护病房(ICU,23例,41.07%)和血液科(17例,30.36%)为主;感染菌株主要为肺炎克雷伯菌(32例,57.14%)和大肠埃希菌(16例,28.57%)。单因素分析结果显示,恶性肿瘤、60 d内住院史、感染前入住ICU>48 h、机械通气、留置中央静脉导管、使用二联及以上抗菌药物、抗菌药物使用时间≥10 d均与CRE血流感染有关(均P<0.05)。多因素logistic回归分析发现,感染前入住ICU>48 h、感染前抗菌药物使用时间≥10 d是医院获得性CRE血流感染的独立危险因素(P<0.05)。结论临床尤其是ICU应关注患者的流行病学史,尽早识别CRE血流感染高危因素的患者,同时合理使用抗菌药物,规范有创操作,以减少医院获得性CRE血流感染的发生。

耐碳青霉烯类肠杆菌感染的危险因素分析和列线图预测模型的构建

目的探讨该院住院患者耐碳青霉烯类肠杆菌(CRE)的耐药特征和危险因素,以及建立列线图模型预测患者发生CRE感染的可能性。方法回顾性选取2018年7月至2023年2月江苏大学附属句容医院住院患者中发生CRE感染的81例患者(81株CRE)作为CRE组,按1∶1原则随机选取同期确诊为碳青霉烯类药物敏感的肠杆菌科细菌(CSE)感染患者81例(81株CSE)作为CSE组。分析CRE组患者标本来源和菌种分布;比较两组患者的基本信息、基本健康状况、侵入性操作史、抗菌药物使用情况等临床资料;采用多因素Logistic回归模型分析住院患者发生CRE感染的影响因素;绘制发生CRE感染的列线图预测模型,并采用校准曲线进行模型性能评估。结果检出CRE的标本主要为痰液标本[72.84%(59/81)],菌株以肺炎克雷伯菌最多见[46.91%(38/81)]。多因素Logistic回归分析结果显示感染前3个月内手术、感染前使用碳青霉烯类药物、感染前使用加酶抑制剂、合并心脑血管疾病及感染前半年内住院次数≥2次是发生CRE感染的危险因素(P<0.05),依此建立该院住院患者发生CRE感染的列线图模型。内部验证结果显示,列线图模型预测CRE感染的C-index为0.898(95%CI:0.849~0.948)。结论本研究构建的列线图模型对该院住院患者发生CRE感染有较好的预测作用,有助于临床早期筛查CRE感染的高风险患者,医务人员可据此制订个体化防治策略,从而降低CRE感染的可能。