Emerge of bla and bla harboring carbapenem-resistant Klebsiella pneumoniae isolates from hospitalized patients in southwestern Iran.
Hosseinzadeh Zahra,Sedigh Ebrahim-Saraie Hadi,Sarvari Jamal,Mardaneh Jalal,Dehghani Behzad,Rokni-Hosseini Seyed Mohammad Hossein,Motamedifar Mohammad
Journal of the Chinese Medical Association : JCMA
BACKGROUND:One of the most important emerging carbapenem-resistant bacteria is Klebsiella pneumoniae (K. pneumoniae). The present study aimed to investigate the antibiotic susceptibility pattern of K. pneumoniae isolates and detection of carbapenemase producing K. pneumoniae obtained from Iranian hospitalized patients. METHODS:This cross-sectional study was performed on 211 K. pneumoniae isolates which were recovered from different clinical specimens from 2014 to 2015. Modified Hodge test (MHT) and double disk synergy test (DDST) were done for detection of carbapenemase and metallo-beta-lactamase (MBL) producing K. pneumoniae. The presence of antibiotic resistance determinants was investigated by polymerase chain reaction (PCR) method. RESULTS:The results of antibiotic susceptibility showed that all isolates were resistant to ampicillin, and then mostly resistant to piperacillin and ceftazidime with 76.3% and 66.8%, respectively. On the other hand, the highest sensitivity was toward polymyxin B, followed by carbapenems. Of 29 carbapenem-resistant isolates, all were high-level imipenem-resistant isolates (Minimum inhibitory concentration ≥4), except 4 isolates. The results of MHT and DDST showed that 93.1% (27/29) of carbapenem-resistant isolates were carbapenemase and MBL producing isolates, respectively. The presence of bla and bla genes was detected in 27 (10.9%) and 2 (0.9%) isolates, respectively. CONCLUSION:This is the first identification of bla and bla in K. pneumoniae in Southwestern Iran and the highest reported prevalence of bla in this bacterium from Iran. Since carbapenem-resistant isolates containing New Delhi metallo-beta-lactamase 1 (NDM-1) were almost resistant to all the tested antibiotics, the resistance due to this gene may be increased in the near future as a potential health threat.
10.1016/j.jcma.2017.08.015
Occurrence of OXA-48 and NDM-1 carbapenemase-producing Klebsiella pneumoniae in a Moroccan university hospital in Casablanca, Morocco.
Barguigua Abouddihaj,Zerouali Khalid,Katfy Khalid,El Otmani Fatima,Timinouni Mohammed,Elmdaghri Naima
Infection, genetics and evolution : journal of molecular epidemiology and evolutionary genetics in infectious diseases
The purpose of this investigation was to determine the prevalence and the characteristics of carbapenemase-producing Klebsiellapneumoniae isolates recovered from various clinical specimens in the university hospital of Casablanca, in Morocco. We conducted a prospective study on a total of 166 K. pneumoniae isolates collected from June to August 2011. The strains suspected to carry carbapenemase showed reduced susceptibility to imipenem or ertapenem. The PCR and a sequencing strategy were used to identify carbapenemases, expended spectrum β-lactamases (ESBL), plasmid-mediated AmpC β-lactamases, plasmid mediated quinolone resistance and aminoglycoside resistance determinants. The clonal relationships between isolates were analyzed by pulsed field gel electrophoresis (PFGE). Among the 166 K. pneumoniae isolates studied, 11 (6%) were carbapenemases producers, 9 of which harbored blaOXA-48 and 2 were positive for blaNDM-1. All carbapenemase-producing K. pneumoniae were also ESBL producers and the blaCTX-M-15 was the most frequent ESBL gene detected (n=9), blaCTX-M-28 and blaSHV-28 were also encountered in one isolate each. The K.pneumoniae isolates carried also non-ESBL genes blaTEM-1 (n=9), blaSHV-1 (n=8) and blaOXA-1 (n=3). Five isolates harbored qnr genes, qnrS1 (n=3) and qnrB1 (n=2) variants. Six isolates were positive for aac(6')-Ib-cr gene and two for aac(3)-II gene. The class 1 integron was detected in five isolates. PFGE has revealed the presence of a clonal dissemination in our hospital. The results of conjugation experiments indicated that blaOXA-48+blaCTX-M-15, blaOXA-48+blaCTX-M-28, blaNDM-1+blaCTX-M-15+blaTEM-1+blaOXA-1+qnrS1+aac(6')-Ib-cr and blaNDM-1+blaCTX-M-15+blaTEM-1+qnrB1+aac(6')-Ib-cr genes were co-transferred and that these genes were carried by a conjugative plasmid of high molecular weight.
10.1016/j.meegid.2015.01.010
Outbreak of -Harboring ST290 in a Tertiary Hospital in China.
Wang Zhengzheng,Li Meilan,Shen Xiaofei,Wang Liangxing,Liu Li,Hao Zhihao,Duan Jingjing,Yu Fangyou
Microbial drug resistance (Larchmont, N.Y.)
The emergence of carbapenem-resistant (CRKP) has posed a great threat to public health. Among 133 nonduplicated CRKP isolates collected between September 2016 and November 2017 in a tertiary hospital in China, 89 (89/133, 66.9%) and 31 (31/133, 23.3%) were positive for and . Multilocus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE) revealed that ST290 represented the majority of NDM-5 producers (67/89, 75.3%) and PFGE cluster E accounted for 50 (50/67, 74.6%) ST290 isolates from the burn ward, suggesting that ST290 clone carrying resulted in an outbreak in this hospital. Whole genome sequencing of the plasmid carrying showed that the resistance gene was located in a ∼49 kb multireplicon plasmid with a peculiar insertion of IS of the IncX3-type plasmid. To the best of our knowledge, this is the first report of outbreak of ST290 clone carrying .
10.1089/mdr.2019.0046
Emergence and dissemination of multidrug-resistant Escherichia coli ST8346 coharboring bla and bla in Southern Taiwan, 2017-2021.
Journal of infection and public health
BACKGROUND:Enterobacterales carrying bla represent an emerging challenge in treating infectious diseases. In this study, we aimed to investigate the characteristics of bla-producing Enterobacterales from three hospitals in southern Taiwan. METHODS:Enterobacterales strains that were nonsusceptible to more than one carbapenem (ertapenem, meropenem, imipenem, or doripenem) were collected from hospitalized patients. Molecular typing for New Delhi metallo-β-lactamase (NDM) and antibiotic susceptibility tests were performed, followed by multilocus sequence typing (MLST), pulsed-field gel electrophoresis (PFGE), and plasmid analysis by PCR-based replicon typing. RESULTS:A total of 1311 carbapenem-nonsusceptible Enterobacterales were isolated from 2017 to 2021. bla-encoding genes were detected in 108 isolates, with 53 (49.1%) harboring bla and 55 (50.9%) harboring bla. The rate of bla detection among isolates decreased to 2% in 2021. However, the rate of E. coli harboring bla increased from 1% to 12% of total isolates during the study period. Of 47 NDM-5-positive E. coli isolates, 44 (93.6%) were ST8346 with high genetic relatedness. E. coli ST8346 isolates showed high-level resistance to both carbapenems and aminoglycosides. Most (38 out of 47, 80.9%) bla-harboring E. coli isolates co-harbored bla. We analyzed the regions harboring bla in E. coli ST8346 via PCR amplification. bla and bla were located on two separate plasmids, IncF and IncX3, respectively. CONCLUSION:The dissemination of E. coli ST8346 caused an increase in bla and bla co-harboring Enterobacterales in southern Taiwan, which show high-level resistance to both carbapenems and aminoglycosides. We identified a distinct IncF plasmid encoding bla that has the potential for rapid spread and needs further surveillance.
10.1016/j.jiph.2023.08.007
Co-existence of NDM-1 and OXA-48 genes in Carbapenem Resistant clinical isolates in Kafrelsheikh, Egypt.
African health sciences
BACKGROUND:The noteworthy spread of carbapenem-resistant (CR-KP) isolates represents a significant safety threat. OBJECTIVE:Determination of the carbapenemase genes incidence among CR-KP clinical isolates in Kafrelsheikh, Egypt. METHODS:A total of 230 isolates were recovered from four hospitals in Kafrelsheikh, Egypt. Susceptibility testing was conducted using Kirby-Bauer method and automated-Vitek2 system. CR-KP isolates were tested using modified Hodge test (MHT) and combined disk synergy test. PCR and DNA sequencing were conducted for CR-KP isolates to recognize the included carbapenemase-genes. RESULTS:Out of 230 isolates, 50 isolates presented resistance to carbapenem (meropenem). All 50 CR-KP isolates were multidrug-resistant (MDR). Genes like blaNDM-1 and blaOXA-48 were the only detected genes among CR-KP with an incidence of 70.0% and 52.0%, respectively. Up to 74.0% of the tested isolates carried at least one of the two recorded genes, among them 48.0% co-harbored both blaNDM-1 and blaOXA-48 genes. The accession-numbers of sequenced blaNDM-1 and blaOXA-48 genes were MG594615 and MG594616, respectively. CONCLUSION:This study reported a high incidence of MDR profile with the emergence of blaNDM-1 and blaOXA-48 genes co-existence in CR-KP isolates in Kafrelsheikh, Egypt. Hence, more restrictions should be applied against the spread of such serious pathogens.
10.4314/ahs.v21i2.2
Outbreak caused by multidrug-resistant OXA-48 and NDM-1 producing Klebsiella pneumoniae in the intensive care unit of a cancer hospital.
Acta microbiologica et immunologica Hungarica
We report a nosocomial outbreak caused by a multidrug-resistant carbapenemase-producing Klebsiella pneumoniae (MDRCPKp), that was detected in six patients admitted to the medical intensive care unit between 20th of December 2023 and 15th of January 2024 in Ankara, Turkey. The investigation of this outbreak was started on 29th of December 2023. During the outbreak 11 samples were collected from the six patients with MDRCPKp. Pulsed-field gel electrophoresis (PFGE) was performed to determine the genetic relatedness and clonality of MDRCPKp strains. MDRCPKp was isolated in the tracheal aspiration culture, blood, urine, and screening samples. Five patients with MDRCPKp colonization developed healthcare-associated infection. In one patient MDRCPKp was isolated from tracheal aspirate and the screening cultures were considered as colonization not infection. PFGE analysis revealed that all isolates belonged to the same K. pneumoniae clone. MDRCPKp strain of this outbreak exhibited multidrug resistance and co-produced OXA-48 and NDM-1. This outbreak ended after application of strict infection control measures. An outbreak of MDRCPKp can occur in hospitals, especially in the intensive care units; thus, it should be detected early by infection control teams. A strong collaboration between infection control team and microbiology laboratory is essential to cope with MDR bacterial outbreaks in hospitals.
10.1556/030.2024.02364
Prevalence and drug resistance characteristics of carbapenem-resistant Enterobacteriaceae in Hangzhou, China.
Yang Yan,Chen Jian,Lin Di,Xu Xujian,Cheng Jun,Sun Changgui
Frontiers of medicine
With the abuse of antimicrobial agents in developing countries, increasing number of carbapenem-resistant Enterobacteriaceae (CRE) attracted considerable public concern. A retrospective study was conducted based on 242 CRE strains from a tertiary hospital in Hangzhou, China to investigate prevalence and drug resistance characteristics of CRE in southeast China. Bacterial species were identified. Antimicrobial susceptibility was examined by broth microdilution method or epsilometer test. Resistant β-lactamase genes were identified by polymerase chain reaction and sequencing. Genotypes were investigated by phylogenetic analysis. Klebsiella pneumoniae and Escherichia coli were the most prevalent types of species, with occurrence in 71.9% and 21.9% of the strains, respectively. All strains exhibited high resistance (> 70%) against β-lactam antibiotics, ciprofloxacin, trimethoprim-sulfamethoxazole, and nitrofurantoin but exhibited low resistance against tigecycline (0.8%) and minocycline (8.3%). A total of 123 strains harbored more than two kinds of β-lactamase genes. bla, bla, bla, and bla were the predominant genotypes, with detection rates of 60.3%, 61.6%, 43.4%, and 16.5%, respectively, and were highly identical with reference sequences in different countries, indicating potential horizontal dissemination. IMP-4 was the most frequent class B metallo-lactamases in this study. In conclusion, continuous surveillance and effective prevention should be emphasized to reduce spread of CRE.
10.1007/s11684-017-0529-4
Molecular characterization of carbapenem- resistant Enterobacteriaceae yields increasing rates of NDM-1 carbapenemases and colistin resistance in an OXA-48- endemic area.
Cizmeci Zeynep,Aktas Elif,Otlu Baris,Acikgoz Ozlem,Ordekci Seyhan
Journal of chemotherapy (Florence, Italy)
We aimed to characterize carbapenem-resistant isolates in a tertiary hospital in Istanbul, Turkey, high-prevelance area for OXA-48 producers. About 76 Enterobacteriaceae clinical isolates were included. Carbapenemase production was detected by Carbapenem Inactivation Method and carbapenemase genes were investigated by PCR. The clonal relationships were evaluated by AP-PCR. Nineteen Klebsiella pneumoniae isolates were colistin resistant. About 75 isolates yielded carbapenemase by CIM. 52 OXA-48, 17 NDM-1 and 2 VIM-5 carbapenemase genes were detected. Co-production of 'OXA-48 and NDM-1' and 'OXA-48 and VIM-5' were demonstrated in two Klebsiella pneumoniae isolates. The total clustering rate was 20.2%. About 69 Klebsiella pneumoniae yielded 60 profiles and 12 isolates formed five clusters. We have demonstrated the presence of OXA-48 carbapenemases in the majority of isolates in a large collection of carbapenemase-producing isolates from a single hospital. The relatively high rates of NDM-1-producing isolates and colistin resistance is noteworthy.
10.1080/1120009X.2017.1323149
Genomic analysis of extensively drug resistant (XDR) Klebsiella pneumoniae high-risk clone ST14 co-harboring bla and bla recovered from Saudi Arabia.
Journal of infection and public health
BACKGROUND:This study presents a comprehensive genomic analysis of NDM and OXA-48-producing Klebsiella pneumoniae in the Western region of Saudi Arabia, traversed by tens of millions of Muslims from various countries annually. This significant influx of visitors invariably leads to the spread and diversity of MDR bacteria. METHODS:Genome sequencing was performed using MiSeq system of 29 CPKP isolates that were NDM and OXA-48-positive isolated from nosocomial infections and demonstrated resistance to most antibiotics, including carbapenems. RESULTS:WGS analysis showed that 12 (41.3%) isolates co-harbored blabla and bla genes. Notably, 16 (55.1%) isolates were identified as high-risk clone ST14, with 50% of these isolates co-harbored bla, bla and bla genes. All ST14 isolates were identified as capsular genotype KL2 and O1/O2v1 antigen with yersiniabactin locus ypt 14 carried by ICEKp5. The two isolates were identified as ST2096/KL64 hypervirulent K. pneumoniae (hvKp) clone harboring several virulence factors, including the regulator of the mucoid phenotype rmpA2 and aerobactin (iuc-1). Interestingly, two of the hvKp ST383/KL30 isolates were resistant to all tested antimicrobials except colistin and tigecycline, and simultaneously carried numerous ESBLs and carbapenemase genes. These isolates also harbor several virulence factors such as rmpA1, rmpA2, carried on KpVP-1, and aerobactin (iuc-1). CONCLUSION:this study provides insights into the spread and prevalence of high-risk clones of CPKP in the Western region of Saudi Arabia. The ST14 high-risk clone appears to be the predominant CPKP clone in this region, posing a significant threat to public health. This study also reports the presence of two globally disseminated hypervirulent K. pneumoniae (hvKp) clones, namely ST2096 and ST383. Therefore, it is essential to improve surveillance and implement strict infection control measures in this region, which receives a substantial number of visitors to effectively monitor and reduce the spread of high-risk clones of antimicrobial-resistant bacteria, including CPKP.
10.1016/j.jiph.2024.02.011
Emergence of two novel sequence types (3366 and 3367) NDM-1- and OXA-48-co-producing K. pneumoniae in Italy.
Gona Floriana,Bongiorno Dafne,Aprile Ausilia,Corazza Erika,Pasqua Betta,Scuderi Maria Grazia,Chiacchiaretta Matteo,Cirillo Daniela Maria,Stefani Stefania,Mezzatesta Maria Lina
European journal of clinical microbiology & infectious diseases : official publication of the European Society of Clinical Microbiology
The aim of this study was to analyze the alarming spread of NDM-1- and OXA-48-co-producing Klebsiella pneumoniae clinical isolates, collected between October 2016 and January 2018 in a neonatal intensive care unit of the University Hospital, Catania, Italy, through whole genome sequencing. All confirmed carbapenem-resistant K. pneumoniae (CRKp) isolates were characterized pheno- and geno-typically, as well as by whole genome sequencing (WGS). A total of 13 CRKp isolates were identified from 13 patients. Pulsed-field gel electrophoresis (PFGE) was performed, and the multilocus sequence typing (MLST) scheme used was based on the gene sequence as published on the MLST Pasteur website. Core genome MLST (cgMLST) was also performed. All isolates co-carried bla and bla genes located on different plasmids belonging to the IncM/L and IncA/C2 groups, respectively. The 13 strains had identical PFGE profiles. MLST and cgMLST showed that K. pneumoniae was dominated by CRKp ST101 and two novel STs (ST3666 and ST3367), identified after submission to the MLST database for ST assignment. All isolates shared the same virulence factors such as type 3 fimbriae, genes for yersiniabactin biosynthesis, yersiniabactin receptor, and iron ABC transporter. They carried the wzi137 variant associated with the K17 serotype. To the best of our knowledge, this is the first report of two novel STs, 3366 and 3367, NDM-OXA-48-co-producing K. pneumoniae clinical isolates, in Italy.
10.1007/s10096-019-03597-w
The emergence of OXA-48- and NDM-1-positive Klebsiella pneumoniae in Riyadh, Saudi Arabia.
Shibl Atef,Al-Agamy Mohamed,Memish Ziad,Senok Abiola,Khader Shamshad Abdul,Assiri Abdullah
International journal of infectious diseases : IJID : official publication of the International Society for Infectious Diseases
OBJECTIVES:To investigate the emergence of NDM-, OXA-48-, and VIM-producing Klebsiella pneumoniae in Saudi Arabia. METHODS:From June to December 2011, we obtained K. pneumoniae isolates with reduced sensitivity to carbapenem identified in Riyadh, Saudi Arabia. Only non-duplicate clinical and surveillance isolates obtained from inpatients were included. PCR amplification was carried out for the detection of extended-spectrum beta-lactamase genes (blaCTX-M, blaTEM, blaSHV) and carbapenemase genes (blaKPC, blaVIM, blaIMP, blaNDM, and blaOXA-48). Susceptibility to imipenem, meropenem, amikacin, gentamicin, trimethoprim-sulfamethoxazole, and colistin was determined. RESULTS:Of the 60K. pneumoniae isolates studied, 45 were from patients in the intensive care unit. Forty-seven isolates harbored blaOXA-48, 12 were positive for blaNDM, and one for blaVIM. No isolate harbored a combination of these resistance genes. No isolate harbored blaKPC or blaIMP. All 37 blaCTX-M-positive isolates belonged to CTX-M group 1, and 29 were positive for a combination of blaCTX-M and blaOXA-48. blaTEM and blaSHV genes were found in 17 and 39 isolates, respectively. All isolates were imipenem- and meropenem-resistant, with a high rate of co-resistance to the other antibiotics. Three blaOXA-48-positive isolates with colistin resistance were detected. CONCLUSION:Multidrug-resistant K. pneumoniae isolates harboring blaOXA-48, blaNDM, and colistin resistance are emerging in Saudi Arabia.
10.1016/j.ijid.2013.06.016
A Nationwide Genomic Study of Clinical Klebsiella pneumoniae Carrying and in China.
Microbiology spectrum
OXA-232 carbapenemase is becoming a threat in China due to its high prevalence, mortality, and limited treatment options. However, little information is available on the impact of OXA-232-producing Klebsiella pneumoniae in China. This study aims to characterize the clonal relationships, the genetic mechanisms of resistance, and the virulence of OXA-232-producing K. pneumoniae isolates in China. We collected 81 OXA-232-producing K. pneumoniae clinical isolates from 2017 to 2021. Antimicrobial susceptibility testing was performed using the broth microdilution method. Capsular types, multilocus sequence types, virulence genes, antimicrobial resistance (AMR) determinants, plasmid replicon types, and single-nucleotide polymorphism (SNP) phylogeny were inferred from whole-genome sequences. OXA-232-producing K. pneumoniae strains were resistant to most antimicrobial agents. These isolates showed partial differences in susceptibility to carbapenems: all strains were resistant to ertapenem, while the resistance rates to imipenem and meropenem were 67.9% and 97.5%, respectively. Sequencing and capsular diversity analysis of the 81 K. pneumoniae isolates revealed 3 sequence types (ST15, ST231, and one novel ST [ST-V]), 2 K-locus types (KL112 and KL51), and 2 O-locus types (O2V1 and O2V2). The predominant plasmid replicon types associated with the OXA-232 and genes were ColKP3 (100%) and IncFIB-like (100%). Our study summarized the genetic characteristics of OXA-232-producing K. pneumoniae circulating in China. The results demonstrate the practical applicability of genomic surveillance and its utility in providing methods to prevent transmission. It alerts us to the urgent need for longitudinal surveillance of these transmissible lineages. In recent years, the detection rate of carbapenem-resistant K. pneumoniae has increased and represents a major threat to clinical anti-infective therapy. Compared with KPC-type carbapenemases and NDM-type metallo-β-lactamases, OXA-48 family carbapenemases are another important resistance mechanism mediating bacterial resistance to carbapenems. In this study, we investigated the molecular characteristics of OXA-232 carbapenemase-producing K. pneumoniae isolated from several hospitals to clarify the epidemiological dissemination characteristics of such drug-resistant strains in China.
10.1128/spectrum.03863-22
Molecular detection of OXA-48 and NDM-1 carbapenemase genes among clinical isolates of Klebsiella pneumoniae recovered from patients attending a private tertiary hospital in Southwestern Nigeria.
BMC infectious diseases
There have been increasing reports of Klebsiella pneumoniae resistant to β-lactam antibiotics. This study aimed to determine the prevalence of some selected carbapenemase genes among clinical isolates of Klebsiella pneumoniae recovered from patients attending a private tertiary hospital in Southwestern Nigeria. The study was conducted over two months (February-March 2024). A total of 50 clinical isolates of Klebsiella pneumoniae from different clinical specimens were obtained from the Medical Microbiology Department, Babcock University Teaching Hospital (BUTH). The clinical isolates were then characterized using standard microbiological procedures and were tested for susceptibility to meropenem and other classes of antibiotics according to Clinical and Laboratory Standards Institute (CLSI) guidelines. Polymerase Chain Reaction (PCR) detection for OXA-48 and NDM-1 carbapenemase genes was performed on the 50 clinical isolates. PCR analysis showed that 9 (18%) clinical isolates were positive for the OXA-48 gene, 22 (44%) were positive for the NDM-1 gene, 4 (8%) possessed both the OXA-48 and NDM-1 genes, and 23 (46%) possessed neither the OXA-48 nor NDM-1 genes. Antibiotic Susceptibility Testing (AST) revealed that all the clinical isolates were resistant to meropenem. In conclusion, this study demonstrates the presence of OXA-48 and NDM-1 genes in clinical isolates of Klebsiella pneumoniae recovered from patients attending a private tertiary hospital in Southwestern Nigeria, highlighting the role of ESBL (extended-spectrum beta-lactamase) as a major resistance mechanism alongside other mechanisms. Population-based surveillance programs should be implemented to monitor the prevalence and epidemiology of Klebsiella pneumoniae infections at the community level, facilitating early detection of outbreaks and identification of emerging antimicrobial resistance patterns. CORE TIP: This study highlights the significant prevalence of NDM-1 and OXA-48 carbapenemase genes among Klebsiella pneumoniae clinical isolates in a private tertiary hospital in Southwestern Nigeria, with 44% and 18% of isolates harboring these genes, respectively. Notably, 46% of isolates were resistant to carbapenems despite lacking these genes, suggesting alternative resistance mechanisms. The findings underscore the urgent need for enhanced surveillance, infection control measures, and antibiotic stewardship programs to combat the spread of multidrug-resistant Klebsiella pneumoniae in healthcare settings.
10.1186/s12879-024-09869-x
Coexistence of and Truncated on Different Plasmids in a Isolate in China.
Xie Lianyan,Dou Yi,Zhou Kaixin,Chen Yue,Han Lizhong,Guo Xiaokui,Sun Jingyong
Frontiers in microbiology
To describe the genetic environment, transferability, and antibiotic susceptibility of one clinical isolate harboring both and on different plasmids from a Chinese hospital. The isolate was subjected to antimicrobial susceptibility testing and multilocus sequence typing using Etest and PCR. The plasmids harboring and were analyzed through conjugation experiments, S1-nuclease pulsed-field gel electrophoresis, and hybridization with specific probes. Plasmid DNA was sequenced using Pacbio RS II and annotated using RAST. RJ119, carrying both and , was resistant to almost all carbapenems, cephalosporins, fluoroquinolone, and aminoglycosides and belonged to ST307. was located on a 61,748-bp IncL/M conjugative plasmid, which displayed overall nucleotide identity (99%) to pKPN-E1-Nr.7. was located on a 335,317-bp conjugative plasmid, which was a fusion of a -harboring InA/C plasmid pNDM-US (140,825 bp, 99% identity) and an IncFIB plasmid pKPN-c22 (178,563 bp, 99% identity). The transconjugant RJ119-1 harboring was susceptible to carbapenem, and there was an insertion of IS into the gene. This is the first report of the coexistence of and in one clinical isolate in China. OXA-48 in RJ119 contributed to the majority to its high resistance to carbapenems, whereas NDM-1 remained unexpressed, most likely due to the insertion of IS. Our results provide new insight for the relationship between genetic diagnosis and clinical treatment. They also indicate that increased surveillance of is urgently needed in China.
10.3389/fmicb.2017.00133
Molecular epidemiology of NDM-1- and OXA-48-producing Klebsiella pneumoniae in an Iranian hospital: clonal dissemination of ST11 and ST893.
Solgi Hamid,Badmasti Farzad,Giske Christian G,Aghamohammad Shadi,Shahcheraghi Fereshteh
The Journal of antimicrobial chemotherapy
Objectives:Despite the fact that the blaOXA-48 and blaNDM-1 genes have successfully disseminated among Klebsiella pneumoniae isolates worldwide, outbreaks remain unidentified in Iran. Here we examined the molecular epidemiology of 96 carbapenem-resistant K. pneumoniae recovered from an Iranian hospital. Methods:A total of 96 non-replicate carbapenem-resistant K. pneumoniae were recovered from clinical specimens in a university hospital. Detection of ESBLs and carbapenemases produced by studied strains was performed using PCR and DNA sequencing. The bacterial isolates were assigned to clonal lineages by PFGE and MLST. In addition, plasmids were analysed by PCR-based replicon typing and conjugation assays. Results:All isolates harboured blaOXA-48 and blaNDM-1 genes together or alone. Almost all strains also carried ESBL genes. Eighty-seven isolates of K. pneumoniae were categorized into seven pulsotypes. The predominant strain clusters/pulsotypes associated with the outbreak corresponded to ST11 (48/96) and ST893 (31/96). Plasmids carrying blaOXA-48 and blaNDM-1 were successfully transferred to Escherichia coli K12 as the recipient strain. blaOXA-48 was located on IncL/M plasmids of ∼39 kb, while blaNDM-1 was carried by either an IncFII plasmid of ∼50 kb or an untypeable plasmid of ∼4 or 10 kb. Conclusions:We describe two separate outbreaks of blaOXA-48- and blaNDM-1-carrying K. pneumoniae strains associated with dissemination of the ST11 and ST893 clones, with the ICU acting as the epicentre. The spread of plasmids carrying carbapenemase genes resulting in fulminant antimicrobial resistance is a severe concern.
10.1093/jac/dky081
Hypervirulent Klebsiella pneumoniae: An update on epidemiology, detection and antibiotic resistance.
Acta microbiologica et immunologica Hungarica
Klebsiella pneumoniae is a major human pathogen as it is responsible for various infections. In the past years hypervirulent K. pneumoniae (hvKP) emerged and disseminated worldwide. In this review a summary will be given about epidemiology, detection and antibiotic resistance of hypervirulent K. pneumoniae. A common feature of hypervirulent K. pneumoniae is a combined expression of several virulence factors. A mucoviscosus phenotype, certain capsulare serotypes (e.g.: K1, K2, K28, K47, K63) together with additional genetic markers namely, magA, rmpA or iucABCD, are needed in combinations to achieve the hypervirulent pathotype. Plasmid coded virulence determinants are also detected, that indicates horizontal gene transfer of hypervirulence factors in K. pneumoniae.Interestingly, infections caused by hypervirulent K. pneumoniae occur usually in the community in otherwise healthy people, and during these infections multiple infection sites are detected. Clinical pictures include both invasive infections and local abscess formation. Pyogenic liver abscess is the most frequently reported clinical manifestation and abscess formation in brain, spleen and lung are also diagnosed. Additionally, meningitis, endophthalmitis, trombophlebitis, pneumonia can also develop.In the early reports, hypervirulent K. pneumoniae strains exhibited enhanced virulence but these were susceptible to commonly used antibiotics. However, recently KPC, VIM, NDM and OXA-48 carbapenemase producing hypervirulent K. pneumoniae strains are increasingly reported, furthermore, well-known high-risk K. pneumoniae clones (e.g.: ST11, ST147, ST307) can develop hypervirulent pathotype, that poses an even more alarming challenge.
10.1556/030.2023.02186
Investigation of carbapenem-resistant Klebsiella pneumoniae in Taiwan revealed strains co-harbouring bla and bla and a novel plasmid co-carrying bla and bla.
International journal of antimicrobial agents
The emergence of carbapenem-resistant Klebsiella pneumoniae (CRKP) is related to the transmission of carbapenemase genes. Strains carrying more than one carbapenemase with a broadened spectrum of antibiotic resistance have been detected, which is concerning. Although bla-encoding ST11-KL47/KL64 strains are dominant, other clones are emerging. This study investigated 137 CRKP from patients' blood samples in Taiwan. Polymerase chain reaction (PCR) was used to identify carbapenemase genes and capsular (KL) types. Most strains (56%, 77/137) possessed bla alone; however, 12% (17/137) carried bla+bla and these strains showed high resistance to imipenem and meropenem. Strains carrying bla+bla predominantly belonged to KL51 (n=15), followed by KL64 (n=1) and KL47 (n=1). Whole-genome sequencing of one KL51 strain indicated that bla and bla are carried on two different plasmids. PCR was performed using specific primers located in these plasmids, and all bla+bla-encoding strains except the KL64 strain were considered to carry the two abovementioned plasmids. Genome analysis for the KL64 strain revealed that bla and bla are encoded in one plasmid. Notably, the KL51 bla plasmid shared high sequence similarity with the KL64 bla+bla plasmid, except the KL64 plasmid comprised a 15,040-bp insertion encoding bla. The data revealed KL51 as a predominant KL type carrying bla+bla, and identified a novel plasmid carrying bla+bla, highlighting the spread of specific plasmids and clones of CRKP in Taiwan.
10.1016/j.ijantimicag.2023.106964
Activity of polymyxin B combinations against genetically well-characterised Klebsiella pneumoniae producing NDM-1 and OXA-48-like carbapenemases.
International journal of antimicrobial agents
BACKGROUND:Combination therapy can enhance the activity of available antibiotics against multidrug-resistant Gram-negative bacteria. This study assessed the effects of polymyxin B combinations against carbapenemase-producing Klebsiella pneumoniae (K. pneumoniae). METHODS:Twenty clinical K. pneumoniae strains producing NDM-1 (n = 8), OXA-48-like (n = 10), or both NDM-1 and OXA-48-like (n = 2) carbapenemases were used. Whole-genome sequencing was applied to detect resistance genes (e.g. encoding antibiotic-degrading enzymes) and sequence alterations influencing permeability or efflux. The activity of polymyxin B in combination with aztreonam, fosfomycin, meropenem, minocycline, or rifampicin was investigated in 24-hour time-lapse microscopy experiments. Endpoint samples were spotted on plates with and without polymyxin B at 4 x MIC to assess resistance development. Finally, associations between synergy and bacterial genetic traits were explored. RESULTS:Synergistic and bactericidal effects were observed with polymyxin B in combination with all other antibiotics: aztreonam (11 of 20 strains), fosfomycin (16 of 20), meropenem (10 of 20), minocycline (18 of 20), and rifampicin (15 of 20). Synergy was found with polymyxin B in combination with fosfomycin, minocycline, or rifampicin against all nine polymyxin-resistant strains. Wildtype mgrB was associated with polymyxin B and aztreonam synergy (P = 0.0499). An absence of arr-2 and arr-3 was associated with synergy of polymyxin B and rifampicin (P = 0.0260). Emergence of populations with reduced polymyxin B susceptibility was most frequently observed with aztreonam and meropenem. CONCLUSION:Combinations of polymyxin B and minocycline or rifampicin were most active against the tested NDM-1 and OXA-48-like-producing K. pneumoniae. Biologically plausible genotype-phenotype associations were found. Such information might accelerate the search for promising combinations and guide individualised treatment.
10.1016/j.ijantimicag.2023.106967
Emergence of OXA-48-Producing Klebsiella pneumoniae in Taiwan.
Ma Ling,Wang Jann-Tay,Wu Tsu-Lan,Siu L Kristopher,Chuang Yin-Ching,Lin Jung-Chung,Lu Min-Chi,Lu Po-Liang
PloS one
The isolation of OXA-48-producing Enterobacteriaceae has increased dramatically in Mediterranean countries in the past 10 years, and has recently emerged in Asia. Between January 2012 and May 2014, a total of 760 carbapenem non-susceptible Klebsiella pneumoniae (CnSKP) isolates were collected during a Taiwan national surveillance. Carbapenemases were detected in 210 CnSKP isolates (27.6%), including 162 KPC-2 (n = 1), KPC-3, KPC-17, and NDM-1 (n = 1 each), OXA-48 (n = 4), IMP-8 (n = 18), and VIM-1 (n = 24). The four blaOXA-48 CnSKP isolates were detected in late 2013. Herein we report the emergence OXA-48-producing K. pneumoniae isolates in Taiwan. PFGE analysis revealed that the four isolates belonged to three different pulsotypes. Three isolates harboured blaCTX-M genes and belonged to MLST type ST11. In addition, the plasmids belonged to the incompatibility group, IncA/C. One isolate belonged to ST116 and the plasmid incompatibility group was non-typeable. The sequence upstream of the blaOXA-48 gene in all four isolates was identical to pKPOXA-48N1, a blaOXA-48-carrying plasmid. This is the first report of OXA-48-producing Enterobacteriaceae in Taiwan and the second report to identify blaOXA-48 on an IncA/C plasmid in K. pneumoniae. Given that three isolates belong to the same pandemic clone (ST11) and possess the IncA/C plasmid and similar plasmid digestion profile that indicated the role of clonal spread or plasmid for dissemination of blaOXA-48 gene, the emergence of OXA-48-producing K. pneumoniae in Taiwan is of great concern.
10.1371/journal.pone.0139152
High prevalence of OXA-48-like and NDM carbapenemases among carbapenem resistant of clinical origin from Iran.
Iranian journal of microbiology
Background and Objectives: is increasingly developing resistance to last-resort antibiotics such as carbapenems. This study aimed to investigate the dissemination of common carbapenemase encoding genes among 48 clinical isolates of carbapenem-resistant (CRKP). Materials and Methods:Antimicrobial susceptibility testing was performed by broth dilution and disc diffusion methods. The phenotypic evaluation of carbapenemase production was performed by using Modified Carbapenem Inactivation Method. Presence of carbapenemase encoding genes , , , , and was screened by PCR. Results:Overall, carbapenemases were produced in all CRKP isolates. The and were the most prevalent genes detected among all and 66.6% (n=32) of CRKP isolates respectively. The was detected in only one isolate co-harboring NDM and OXA-48-like carbapenemases. The and genes were not identified in any of the isolates. While tigecycline was the most active agent against CRKP isolates with low resistance rate (4.1%), high rate of resistance was observed to colistin (66.6%), amikacin (79%) and most of other tested antimicrobials. Conclusion:Our results revealed predominant prevalence of OXA-48-like and NDM carbapenemases among CRKP clinical isolates. High rate of resistance to last-resort agents such as colistin among CRKP isolates is a source of great concern.
10.18502/ijm.v15i5.13866
Detection of NDM-1/5 and OXA-48 co-producing extensively drug-resistant hypervirulent Klebsiella pneumoniae in Northern Italy.
Journal of global antimicrobial resistance
OBJECTIVES:Using a hybrid long-read sequencing approach, we aimed to fully characterise four extensively-drug resistant (XDR) hypervirulent Klebsiella pneumoniae isolates, one of which represented the first strain isolated in Italy co-expressing NDM-1/5 and OXA-48 carbapenemases. METHODS:Whole-genome sequencing was performed using Illumina and Oxford Nanopore Technology platforms. An assembly pipeline was used to recover the structures both of the chromosome and plasmids. RESULTS:Multilocus sequence typing (MLST) showed that these strains belonged to high-risk sequence types (STs) not commonly circulating in Italy (ST383, ST147 and ST15). The hybrid sequencing approach allowed to characterise three multidrug resistance plasmids, which demonstrated high homology with previously sequenced plasmids, that were simultaneously detected in one ST383 strain carrying, respectively, bla, bla and bla. CONCLUSION:This is the first report in Italy of new hypervirulent XDR K. pneumoniae clones characterised by co-production of OXA-48, NDM-1 and NDM-5. The discovery of new high-risk clones harbouring multiple mobile elements is a growing problem that poses a great challenge for public health.
10.1016/j.jgar.2022.01.001
Investigation of NDM-1 and OXA-48 producing carbapenem resistant Klebsiella pneumoniae ST15 in Iran.
Acta microbiologica et immunologica Hungarica
The aim of this study was to determine the frequency of carbapenem resistant Klebsiella pneumoniae (CRKP) sequence types (STs) in Iran. Samples were collected from three university hospitals in Sanandaj, Iran, from December 2016 to March 2018. Antibiotic susceptibility testing, phenotypic and genotypic detection of carbapenemases were performed. Common K. pneumoniae capsular types were sought for all isolates. The genetic relatedness of isolates was investigated by multilocus sequence typing (MLST). Plasmids were detected by PCR-based Replicon Typing (PBRT). During the study, 67 K. pneumoniae isolates were identified. Of which, 18 (26.9%) isolates were detected as carbapenem-resistant. The most effective antibacterial agent was tigecycline (97%, 65 isolates) followed by imipenem and ertapenem (73.13%, 49 isolates). PCR showed that 13 isolates (19.4%) had blaNDM-1 gene and 5 (7.5%) harbored blaOXA-48. Examination of common capsular types showed that 2 isolates had K2 and 2 others had K54. REP-PCR revealed 10 clones and 11 singleton strains. MLST analysis of CRKP found ST15 as the most common type (13 isolates, 72.2%), but other STs were also detected namely, ST19, ST117, ST1390, and ST1594. ColE1 and IncL/M plasmids were the carriers of blaNDM-1 and blaOXA-48, respectively. The results showed that CRKP spread in our health centers. Our results, therefore, indicate a worrying trend of resistance to carbapenems in K. pneumoniae.
10.1556/030.2023.01945
High frequency of NDM-1 and OXA-48 carbapenemase genes among Klebsiella pneumoniae isolates in central Iran.
BMC microbiology
BACKGROUND:The emergence and distribution of multidrug-resistant (MDR) and carbapenem-resistant Klebsiella pneumoniae (CRKP) has become a global health threat. Therefore, this study aimed to investigate the frequency and antibiotic resistance patterns of MDR, extensively drug-resistant (XDR), and CRKP, as well as the antibiotic resistance genes of Klebsiella pneumoniae (K. pneumoniae) isolates from patients' infectious samples from central Iran. METHODS:This study examined 546 clinical samples of patients to identify K. pneumoniae. The isolates were investigated for their antibiotic resistance profile, extended-spectrum β-lactamase (ESBL), AMPC β-lactamase, carbapenemase resistance, sulfonamide, tetracycline, plasmid-mediated quinolone resistance (PMQR) along with their resistance genes, integrase, and quaternary ammonium compounds (qac) by polymerase chain reaction (PCR). RESULTS:Out of 546 clinical samples, 121 (22.1%) cases of K. pneumoniae were identified using culture and PCR methods. The highest antibiotic resistance rates were found for ampicillin (119/121; 98.3%), cotrimoxazole (78/121; 64.4%), and cefixime, cefotaxime, ceftriaxone, and ceftazidime as a group (77/121; 63.6%). Tigecycline, colistin, and fosfomycin were the most effective antimicrobial agents with 98.4%, 96.7%, and 95.9% susceptibility, respectively. The amount of CRKP was 51 (42.1%). All CRKP isolates were MDR. The most abundant genes were bla (77/77; 100%), bla (76/77; 98.7%), bla (76/77; 98.7%), bla (73/77; 94.8%) for ESBL; bla 28 (48.3%) and bla 26 (44.8%) for AMPC β-lactamase; and bla 46 (90.1%) and bla 36 (70.5%) for carbapenemase. Among the PMQR determinants, qnrB (25/52; 48%), qnrS (19/52; 36.5%), and qnrA (11/52; 21.1%) were positive from the isolates. TetA and tetB were recognized in 25 (44.6%) and 17 (30.3%) isolates, respectively. Class 1 and 2 integrons were recognized in 97 (80.1%) and 53 (43.8%) isolates, respectively. CONCLUSIONS:Due to the high prevalence of MDR and CRKP in central Iran, tracking and immediate intervention are necessary for control and inhibition of K. pneumoniae resistant isolates. Tigecycline, colistin, and fosfomycin are the best treatment options for treatment of patients with CRKP in this geographical area.
10.1186/s12866-023-02840-x
Emergence of Klebsiella pneumoniae ST11 co-producing NDM-1 and OXA-48 carbapenemases in Greece.
Protonotariou Efthymia,Meletis Georgios,Chatzopoulou Fani,Malousi Andigoni,Chatzidimitriou Dimitrios,Skoura Lemonia
Journal of global antimicrobial resistance
OBJECTIVES:Klebsiella pneumoniae is a well-known pathogen frequently implicated in serious life-threatening nosocomial infections. Here we present a K. pneumoniae isolate (AHEPA1046) co-harbouring bla and bla isolated from a blood sample of an inpatient in Thessaloniki, Greece. METHODS:Whole-genome sequencing (WGS) was performed using an Illumina MiniSeq Sequencing System. Multilocus sequence typing (MLST) was performed using a BLAST-based approach, and antimicrobial resistance genes and plasmid replicons were identified by ResFinder and PlasmidFinder, respectively. The Rapid Annotation using Subsystem Technology (RAST) v.2.0 server was used for genome annotation. RESULTS:WGS analysis revealed the complete resistome of K. pneumoniae AHEPA1046. The strain harboured bla and bla together with 16 additional antimicrobial resistance genes and was resistant to carbapenems, aminoglycosides, quinolones, macrolides, tetracyclines, trimethoprim, fosfomycin and phenicols. Moreover, it was classified as ST11. CONCLUSION:This is the first report of a K. pneumoniae clinical isolate from Greece co-producing NDM-1 and OXA-48 carbapenemases and is one of a few reported worldwide.
10.1016/j.jgar.2019.08.020
Carbapenem-resistant hypermucoviscous clinical isolates from a tertiary hospital in China: Antimicrobial susceptibility, resistance phenotype, epidemiological characteristics, microbial virulence, and risk factors.
Frontiers in cellular and infection microbiology
Hypervirulent and multidrug-resistant poses a significant threat to public health. We aimed to determine the common carbapenemase genotypes and the carriage patterns, main antibiotic resistance mechanisms, and susceptibility of clinical isolates of carbapenem-resistant (CRKP) to ceftazidime/avibactam (CZA) for the reasonable selection of antimicrobial agents and determine whether hypermucoviscous (HMV) phenotype and virulence-associated genes are key factors for CRKP colonization and persistence. Antibiotics susceptibility of clinical CRKP isolates and carbapenemase types were detected. CRKP isolates were identified as hypermucoviscous (HMKP) using the string test, and detection of virulence gene was performed using capsular serotyping. The , , , and/or were detected in 96.4% (402/417) of the isolates, and the (64.7%, 260/402) was significantly higher (<0.05) than those of (25.1%), (10.4%), and (4.2%). Carriage of a single carbapenemase gene was observed in 96.3% of the isolates, making it the dominant antibiotic resistance genotype carriage pattern ( < 0.05). Approximately 3.7% of the isolates carried two or more carbapenemase genotypes, with + and + being the dominant multiple antibiotic resistance genotype. In addition, 43 CRKP isolates were identified as HMKP, with a prevalence of 10.3% and 2.7% among CRKP and all isolates, respectively. Most clinical CRKP isolates were isolated from elderly patients, and carbapenemase production was the main mechanism of drug resistance. Tigecycline and polymyxin B exhibited exceptional antimicrobial activity against CRKP isolates . Furthermore, , , and were the main carbapenemase genes carried by the CRKP isolates. CZA demonstrated excellent antimicrobial activity against isolates carrying the single or genotype. Capsular serotype K2 was the main capsular serotype of the carbapenem-resistant HMKP isolates. Survival rates of injected with 1-7 were 20.0, 16.7, 6.7, 23.3, 16.7, 3.3, and 13.3, respectively. Therefore, worldwide surveillance of these novel CRKP isolates and carbapenem-resistant HMKP isolates as well as the implementation of stricter control measures are needed to prevent further dissemination in hospital settings.
10.3389/fcimb.2022.1083009
Molecular and Clinical Characteristics of Carbapenem-Resistant Isolates at a Tertiary Hospital in Wuhan, China.
Infection and drug resistance
Background:Carbapenem resistant Klebsiella pneumoniae (CRKP) is an independent risk factor for nosocomial infection which poses a serious threat to human health. How to prevent and suppress CRKP infection and explore its drug resistance mechanisms have become a huge challenge and possesses immediate significance. Methods:A total of 45 CRKP strains isolated from hospitalized patients in Zhongnan Hospital of Wuhan University were collected from August 2018-December 2020. The strain's identification and antimicrobial susceptibility tests were performed using the VITEK 2 automated identification instrument. Single molecule DNA sequencing of 45 CRKP isolates was performed by the third generation high-throughput sequencing technology. Results:The results were analyzed by multi locus sequence typing (MLST) and phylogenetic analysis. Antimicrobial susceptibility showed that 45 CRKP isolates were multi-drug resistant strains, and the resistance rates to common antibiotics were as high as 68%. Whole genome sequencing results showed that the CRKP strains carried multiple drug resistance genes and virulence factors. MLST analysis found two different sequence types (ST), of which 44 were ST11 and 1 was ST1049. Conclusion:Through whole genome sequencing (WGS), we found multiple drug-resistant genes and virulence factors, and there was obvious dominant microbiota. The source was mainly related to nosocomial infection. The ST11-KPC Klebsiella pneumoniae was the main type, which was consistent with the most common type in China. We identified several dominant microbiotas which may serve as a target in the clinical prevention and treatment of severe bacterial infections. Our finding may have a role for guiding clinical antibiotic choosing.
10.2147/IDR.S397975