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1.
Rev. Soc. Bras. Med. Trop ; 54: e02622020, 2021.
Article in English | LILACS, ColecionaSUS, SES-SP | ID: biblio-1143877

ABSTRACT

Abstract INTRODUCTION: Carbapenemase-resistant enterobacteria that produce the bla NDM gene are found worldwide. However, this is the first report of blaNDM in Klebsiella aerogenes in Brazil. METHODS: The identification of bacterial species was performed using anautomated system and confirmed by biochemical tests, 16S rRNA gene sequencing, and detection of resistance genes. RESULTS: The clinical isolate showed minimum inhibitory concentration resistance to meropenem and polymyxin B at 8mg/L and 4mg/L, respectively. Only the blaNDM gene was detected. CONCLUSIONS: The current report of the blaNDM gene in isolated MDR enterobacteria indicates that this gene can spread silently in a hospital setting.


Subject(s)
Enterobacter aerogenes/genetics , Bacterial Proteins , beta-Lactamases/genetics , Brazil , RNA, Ribosomal, 16S , Microbial Sensitivity Tests , Drug Resistance, Multiple, Bacterial/genetics , Enterobacteriaceae , Klebsiella pneumoniae/genetics , Anti-Bacterial Agents/pharmacology
2.
Rev. Soc. Bras. Med. Trop ; 54: e20190524, 2021. tab, graf
Article in English | LILACS, ColecionaSUS, SES-SP | ID: biblio-1136925

ABSTRACT

Abstract INTRODUCTION: The aac(6')-Ib-cr and bla KPC genes are spreading among Enterobacteriaceae species, including Providencia stuartii, in some countries of world. METHODS: These genes were investigated in 28 P. stuartii isolates from a public hospital in Recife, Pernambuco, Brazil, by PCR and sequencing. RESULTS: The aac(6')-Ib-cr gene was detected in 16 resistant isolates, and the bla KPC gene was seen in 14. CONCLUSIONS: The presence of these genes in P. stuartii multi- and extensively drug-resistant isolates indicates that the resistance arsenal of this species is increasing, thus limiting the therapeutic options.


Subject(s)
Humans , Enterobacteriaceae Infections , Plasmids , beta-Lactamases/genetics , Brazil , Microbial Sensitivity Tests , Providencia , Drug Resistance, Multiple, Bacterial , Anti-Bacterial Agents/pharmacology
3.
Rev. Soc. Bras. Med. Trop ; 54: e20200087, 2021. tab, graf
Article in English | LILACS, ColecionaSUS, SES-SP | ID: biblio-1136920

ABSTRACT

Abstract INTRODUCTION: In this study, we report a clonal dissemination of carbapenem resistant Acinetobacter baumannii isolates due to the acquisition of blaOXA-23 in a regional hospital located in Brazilian Amazon Region. METHODS: The isolates were identified by MALDI-TOF and the carbapenemase-encoding genes were detected by multiplex-PCR. The genetic similarity was investigated by pulsed-field gel electrophoresis (PFGE). RESULTS: Only 10 (55.6%) isolates harbored the gene bla OXA-23. PFGE analysis revealed that these isolates belong to a single clone. CONCLUSIONS: This dissemination strategy indicates the need for surveillance, adoption of control procedures defined in guidelines, and the careful administration of antimicrobials should be reinforced.


Subject(s)
Humans , Acinetobacter Infections/epidemiology , Acinetobacter baumannii/genetics , Bacterial Proteins/genetics , beta-Lactamases/genetics , Brazil/epidemiology , Drug Resistance , Microbial Sensitivity Tests , Electrophoresis, Gel, Pulsed-Field , Molecular Epidemiology , Hospitals , Anti-Bacterial Agents/pharmacology
4.
Rev. Soc. Bras. Med. Trop ; 54: e0864-2020, 2021. tab
Article in English | LILACS | ID: biblio-1155547

ABSTRACT

Abstract Proteus mirabilis is one of the main pathogens causing urinary tract infections and sepsis. To our knowledge, this is the first report of a P. mirabilis hosting bla GES. The presence of these genes was determined using PCR and sequencing. We identified the presence of bla GES-1 in all three isolates. In addition, we identified the bla KPC-2 and bla NDM-1 genes in the two strains. These data emphasize the importance of monitoring and surveillance of all enterobacteria. The circulation of P. mirabilis strains carrying bla GES-1 constitutes a new scenario of resistance in this species and should be an epidemiological alert for global health.


Subject(s)
Proteus mirabilis/genetics , beta-Lactamases/genetics , Microbial Sensitivity Tests , Enterobacteriaceae , Anti-Bacterial Agents
5.
Rev. Soc. Bras. Med. Trop ; 53: e20200064, 2020. tab, graf
Article in English | LILACS, ColecionaSUS, SES-SP | ID: biblio-1136871

ABSTRACT

Abstract INTRODUCTION: Carbapenem-resistant Klebsiella pneumoniae infection lacks treatment options and is associated with prolonged hospital stays and high mortality rates. The production of carbapenemases is one of the most important factors responsible for this multi-resistance phenomenon. METHODS: In the present study, we analyzed the presence of genes encoding carbapenemases in K. pneumoniae isolates circulating in one of the public hospitals in the city of Aracaju, Sergipe, Brazil. We also determined the best combination of drugs that display in vitro antimicrobial synergy. First, 147 carbapenem-resistant K. pneumoniae isolates were validated for the presence of blaKPC, bla GES, bla NDM, bla SPM, bla IMP, bla VIM, and bla OXA-48 genes using multiplex polymerase chain reaction. Thereafter, using two isolates (97 and 102), the role of double and triple combinational drug therapy as a treatment option was analyzed. RESULTS: Seventy-four (50.3%) isolates were positive for bla NDM, eight (5.4%) for bla KPC, and one (1.2%) for both bla NDM and bla KPC. In the synergy tests, double combinations were better than triple combinations. Polymyxin B and amikacin for isolate 97 and polymyxin B coupled with meropenem for isolate 102 showed the best response. CONCLUSIONS: Clinicians in normal practice use multiple drugs to treat infections caused by multi-resistant microorganism; however, in most cases, the benefit of the combinations is unknown. In vitro synergistic tests, such as those described herein, are important as they might help select an appropriate multi-drug antibiotic therapy and a correct dosage, ultimately reducing toxicities and the development of antibiotic resistance.


Subject(s)
Humans , Bacterial Proteins/genetics , beta-Lactamases/genetics , Klebsiella Infections/microbiology , Klebsiella pneumoniae/drug effects , Anti-Bacterial Agents/pharmacology , Brazil , DNA, Bacterial , Microbial Sensitivity Tests , Polymerase Chain Reaction , Prevalence , Drug Resistance, Multiple, Bacterial/genetics , Klebsiella pneumoniae/isolation & purification , Klebsiella pneumoniae/genetics
6.
Rev. Soc. Bras. Med. Trop ; 53: e20190526, 2020. tab, graf
Article in English | LILACS, ColecionaSUS, SES-SP | ID: biblio-1136834

ABSTRACT

Abstract INTRODUCTION: This study investigated the genetic environment of bla KPC-2 in Klebsiella pnemoniae multi-drug resistant clinical isolates. METHODS: Four carbapenemase gene isolates resistant to carbapenems, collected from infected patients from two hospitals in Brazil, were investigated using polymerase chain reaction and plasmid DNA sequencing. RESULTS: The bla KPC-2 gene was located between ISKpn6 and a resolvase tnpR in the non-Tn4401 element (NTEKPC-IId). It was detected on a plasmid belonging to the IncQ1 group. CONCLUSIONS To our knowledge, this is the first report of the presence of the bla KPC-2 gene in the NTEKPC-IId element carried by plasmid IncQ1 from infections in Brazil.


Subject(s)
Humans , beta-Lactamases/genetics , Klebsiella Infections/microbiology , Klebsiella pneumoniae/genetics , Anti-Bacterial Agents/pharmacology , Plasmids/genetics , DNA, Bacterial/genetics , Microbial Sensitivity Tests , Polymerase Chain Reaction , Drug Resistance, Multiple, Bacterial , Klebsiella pneumoniae/isolation & purification , Klebsiella pneumoniae/enzymology
7.
Rev. Soc. Bras. Med. Trop ; 53: e20200397, 2020. tab, graf
Article in English | LILACS, ColecionaSUS, SES-SP | ID: biblio-1136816

ABSTRACT

Abstract INTRODUCTION Antibiotic resistance in carbapenemase-producing Klebsiella pneumoniae is acquired and disseminated mainly by plasmids. Therefore, we aimed to investigate the occurrence of carbapenemase genes, analyze the genetic diversity by ERIC-PCR, and examine the most common plasmid incompatibility groups (Incs) in clinical isolates of K. pneumoniae from colonization and infection in patients from a hospital in Brazil. METHODS Twenty-seven isolates of carbapenem-resistant K. pneumoniae were selected and screened for the presence of carbapenemase genes and Incs by PCR, followed by amplicon sequencing. RESULTS The bla KPC and bla NDM genes were detected in 24 (88.8 %) and 16 (59.2 %) of the isolates, respectively. Thirteen isolates (48.1 %) were positive for both genes. The IncFIB (92.6 %) and IncQ (88.8 %) were the most frequent plasmids, followed by IncA/C, IncHI1B, and IncL/M, indicating that plasmid variability existed in these isolates. To our knowledge, this is the first report of IncHI1B in Brazil. We found eight isolates with clonal relationship distributed in different sectors of the hospital. CONCLUSIONS The accumulation of resistance determinants, the variability of plasmid Incs, and the clonal dissemination detected in K. pneumoniae isolates demonstrate their potential for infection, colonization, and the dissemination of different resistance genes and plasmids.


Subject(s)
Humans , Klebsiella Infections , Klebsiella pneumoniae/genetics , Plasmids/genetics , Bacterial Proteins/genetics , beta-Lactamases/genetics , Brazil , Microbial Sensitivity Tests , Hospitals, Public , Anti-Bacterial Agents/pharmacology
8.
Rev. Soc. Bras. Med. Trop ; 53: e20190044, 2020. tab
Article in English | LILACS | ID: biblio-1057279

ABSTRACT

Abstract INTRODUCTION: Acinetobacter baumannii are opportunistic bacteria, highly capable of acquiring antimicrobial resistance through the production of carbapenemases and aminoglycoside modifying enzymes (AMEs). METHODS: Carbapenemase and AME genes were investigated in A. baumannii recovered from inpatients of a Brazilian hospital. RESULTS: The key genes found were bla OXA-51-like, the association ISAba1- bla OXA-23-like, and the AME genes aph(3´)-VI, aac(6´)-Ib, aac(3)-Ia, and aph(3´)-Ia. Different clusters spread through the institution wards. CONCLUSIONS: The dissemination of bla OXA-23-like and AME-carrying A. baumannii through the hospital highlights the need for improved preventive measures to reduce the spread of infection.


Subject(s)
Humans , Bacterial Proteins/genetics , beta-Lactamases/genetics , Acinetobacter Infections/microbiology , Acinetobacter baumannii/enzymology , Aminoglycosides/genetics , Brazil , Microbial Sensitivity Tests , Drug Resistance, Multiple, Bacterial , Acinetobacter baumannii/isolation & purification , Acinetobacter baumannii/drug effects , Tertiary Care Centers , Intensive Care Units , Anti-Bacterial Agents/pharmacology
9.
Chinese Medical Journal ; (24): 2573-2585, 2020.
Article in English | WPRIM | ID: wpr-877863

ABSTRACT

BACKGROUND@#Carbapenemase-producing Klebsiella pneumoniae (CP-Kp) poses distinct clinical challenges due to extensively drug resistant (XDR) phenotype, and sequence type (ST) 11 is the most dominant blaKPC-2-bearing CP-Kp clone in China. The purpose of this current retrospective study was to explore the genetic factors associated with the success of XDR CP-Kp ST11 strains circulated in the intensive care unit (ICU) of a Chinese tertiary hospital.@*METHODS@#Six ST11 XDR CP-Kp strains were identified between May and December 2014 and validated by minimum inhibitory concentration examination, polymerase chain reaction, and pyrosequencing. The six ST11 XDR CP-Kp, as well as three multi-drug resistant (MDR) and four susceptible strains, were sequenced using single-molecule real-time method. Comprehensively structural and functional analysis based on comparative genomics was performed to identify genomic characteristics of the XDR ST11 CP-Kp strains.@*RESULTS@#We found that ST11 XDR blaKPC-2-bearing CP-Kp strains isolated from inpatients spread in the ICU of the hospital. Functionally, genes associated with information storage and processing of the ST11 XDR CP-Kp strains were more abundant than those of MDR and susceptible strains, especially genes correlative with mobile genetic elements (MGEs) such as transposons and prophages. Structurally, eleven large-scale genetic regions taken for the unique genome in these ST11 XDR CP-Kp strains were identified as MGEs including transposons, integrons, prophages, genomic islands, and integrative and conjugative elements. Three of them were located on plasmids and eight on chromosomes; five of them were with antimicrobial resistance genes and eight with adaptation associated genes. Notably, a new blaKPC-2-bearing ΔΔTn1721-blaKPC-2 transposon, probably transposed and truncated from ΔTn1721-blaKPC-2 by IS903D and ISKpn8, was identified in all six ST11 XDR CP-Kp strains.@*CONCLUSION@#Our findings suggested that together with clonal spread, MGEs identified uniquely in the ST11 XDR CP-Kp strains might contribute to their formidable adaptability, which facilitated their widespread dissemination in hospital.


Subject(s)
Anti-Bacterial Agents , Bacterial Proteins , China , Electrophoresis, Gel, Pulsed-Field , Hospitals , Humans , Klebsiella Infections/drug therapy , Klebsiella pneumoniae/genetics , Microbial Sensitivity Tests , Multilocus Sequence Typing , Pharmaceutical Preparations , Retrospective Studies , beta-Lactamases/genetics
10.
Rev. chil. infectol ; 36(3): 304-311, jun. 2019. tab, graf
Article in Spanish | LILACS | ID: biblio-1013788

ABSTRACT

Resumen Introducción: La expresión de β-lactamasas CTX-M pertenecientes a los grupos 1 y 9 en Klebsiella pneumoniae produce grados altos de resistencia a ceftazidima, y presentan una amplia distribución mundial. Objetivo: Identificar y caracterizar los genes blaCTX-M-Grupo1 y blaCTX-M-Grupo9 en aislados de K. pneumoniae resistentes a ceftazidima en un hospital de San José de Cúcuta, Colombia. Material y Método: Se diseñaron partidores para la identificación de K. pneumoniae y los genes blaCTX-M mediante reacción de polimerasa en cadena (RPC). Posteriormente se realizó el análisis de la relación genética de estos aislados por medio de la RPC basada en secuencias repetitivas (RPC-REP). Resultados: Treinta y ocho por ciento de los 24 aislados identificados por RPC como K. pneumoniae presentaron los genes blaCTX-M-3, blaCTX-M-15 y blaCTX-M-32 (Grupo CTX-M-1) y 42% los genes blaCTX-M14, blaCTX-M-24 y blaCTX-M-27 (Grupo CTX-M-9). El análisis filogenético agrupó los aislados de K. pneumoniae en cuatro clusters, mostrando correlación en los clusters I, II y IV, al comparar los perfiles genéticos con el tipo de muestra y grupo de genes. Discusión: Se encontró una frecuencia similar de los genes blaCTX-M-Grupo1 y blaCTX-M-Grupo 9 en aislados de K. pneumoniae resistentes a ceftazidima. La correlación entre la RPC-REP con los grupos de CTX-M y el tipo de muestra reveló la presencia de tres patrones clonales.


Background: The expression of CTX-M β-lactamases belonging to groups 1 and 9 in Klebsiella pneumoniae produces high levels of resistance to ceftazidime, and they have a wide distribution worldwide. Aim: To identify and characterize the blaCTX-M-Group1 and blaCTX-M-Group9 genes in K. pneumoniae isolates resistant to ceftazidime in a hospital in San José de Cúcuta, Colombia. Material and Methods: Primers were designed for the identification of K. pneumoniae and blaCTX-M genes by PCR. Subsequently, the genetic relationship of these isolates was analyzed by REP-PCR. Results: A 38% of the 24 isolates identified by PCR as K. pneumoniae showed blaCTX-M-3. blaCTX-M-15 y blaCTX-M-32 genes (Group CTX-M-1) and 42% blaCTX-M14. blaCTX-M-24 y blaCTX-M-27 genes (Group CTX-M-9). The phylogenetic analysis grouped the K. pneumoniae isolates into 4 clusters, showing correlation in clusters I, II and IV, when comparing the genetic profiles with the type of sample and group of genes. Discussion: We found a similar frequency of blaCTX-M-Group 1 and blaCTX-M-Group 9 genes in isolates of K. pneumoniae resistant to ceftazidime. The correlation between the REP-PCR with the CTX-M groups and the type of sample revealed the presence of three clonal patterns.


Subject(s)
Humans , Bacterial Proteins/genetics , beta-Lactamases/genetics , Drug Resistance, Bacterial/genetics , Molecular Typing , Klebsiella pneumoniae/genetics , Phylogeny , Bacterial Proteins/isolation & purification , beta-Lactamases/isolation & purification , Ceftazidime , Polymerase Chain Reaction , Colombia , Klebsiella pneumoniae/isolation & purification , Anti-Bacterial Agents
11.
Braz. j. infect. dis ; 23(2): 102-110, Mar.-Apr. 2019. tab, graf
Article in English | LILACS | ID: biblio-1011579

ABSTRACT

ABSTRACT Enterobacteria-producing extended-spectrum β-lactamases (ESBL) play an important role in healthcare infections, increasing hospitalization time, morbidity and mortality rates. Among several ESBLs that emerge from these pathogens, CTX-M-type enzymes had the most successful global spread in different epidemiological settings. Latin America presents high prevalence of CTX-M-2 in ESBL-producing enterobacterial infections with local emergence of the CTX-M-1 group. However, this high prevalence of the CTX-M-1 group has not yet been reported in Chile. The aim of this study was to identify ESBLs among enterobacteria isolated from clinical samples of critically ill patients from southern Chile. One-hundred thirty seven ESBL-producing bacteria were isolated from outpatients from all critical patient units from Hernán Henríquez Aravena Hospital. Phenotype characterization was performed by antibiogram, screening of ESBL, and determination of minimum inhibitory concentration (MIC). PCR was used for genetic confirmation of resistance. Molecular typing was performed by ERIC-PCR. ESBL-producing isolates were identified as Klebsiella pneumoniae (n = 115), Escherichia coli (n = 18), Proteus mirabilis (n = 3), and Enterobacter cloacae (n = 1), presenting multidrug resistance profiles. PCR amplification showed that the strains were positive for blaSHV (n = 111/81%), blaCTX-M-1 (n = 116/84.7%), blaTEM (n = 100/73%), blaCTX-M-2 (n = 28/20.4%), blaCTX-M-9 (0.7%), blaPER-1 (0.7%), and blaGES-10 (0.7%). The multiple production of ESBL was observed in 93% of isolates, suggesting high genetic mobility independent of the clonal relationship. The high frequency of the CTX-M-1 group and a high rate of ESBL co-production are changing the epidemiology of the ESBL profile in Chilean intensive care units. This epidemiology is a constant and increasing challenge, not only in Chile, but worldwide.


Subject(s)
Humans , beta-Lactamases/genetics , Enterobacteriaceae/enzymology , Enterobacteriaceae Infections/enzymology , Enterobacteriaceae Infections/epidemiology , Intensive Care Units/statistics & numerical data , Reference Values , beta-Lactamases/isolation & purification , DNA, Bacterial , Microbial Sensitivity Tests , Chile/epidemiology , Polymerase Chain Reaction , Prevalence , Risk Factors , Enterobacteriaceae/isolation & purification , Enterobacteriaceae/drug effects , Enterobacteriaceae Infections/microbiology , Genotyping Techniques , Anti-Bacterial Agents/pharmacology
12.
Rev. Soc. Bras. Med. Trop ; 52: e20180352, 2019. tab
Article in English | LILACS | ID: biblio-1041560

ABSTRACT

Abstract INTRODUCTION: The emergence of New Delhi metallo-β-lactamase (NDM) is concernig because it reduces the antibiotic therapy options for bacterial infections. METHODS: Resistant and virulent genes from an isolate of Klebsiella pneumoniae derived from a patient with sepsis in a hospital in Recife-PE, Brazil, were investigated using PCR and DNA sequencing. RESULTS: bla NDM-1, aac(6')-Ib-cr and acrB resistance genes, and cps and mrkD virulence genes were detected. CONCLUSIONS To our knowledge, this is the first report on bla NDM-1 in Recife-PE. This detection alerts researchers to the need to control the spread of bla NDM-1 resistance gene by this bacterium in Brazil.


Subject(s)
Humans , Female , Bacterial Proteins/genetics , Virulence/genetics , beta-Lactamases/genetics , Drug Resistance, Multiple, Bacterial/genetics , Klebsiella pneumoniae/genetics , Anti-Bacterial Agents/pharmacology , Microbial Sensitivity Tests , Polymerase Chain Reaction , Sequence Analysis, DNA , Sepsis/microbiology , Klebsiella pneumoniae/drug effects , Klebsiella pneumoniae/enzymology
13.
Rev. Soc. Bras. Med. Trop ; 52: e20180348, 2019.
Article in English | LILACS | ID: biblio-1013316

ABSTRACT

Abstract We report the occurrence in Brazil of the bla NDM-1 gene in Acinetobacter pittii, prior to the previously described first reports regarding the species Providencia rettgeri and Enterobacter hormaechei. Clinical isolates were investigated by polymerase chain reaction followed by bidirectional sequencing, and species was confirmed by 16S rDNA sequencing and matrix-assisted laser desorption-ionization time-of-flight spectrometry. A. pittii carrying bla NDM-1 was confirmed in a patient with no national or international travel history, or transfer from another hospital. The findings warn of the possibility of silent spread of bla NDM-1 to the community.


Subject(s)
Humans , Female , Aged, 80 and over , Acinetobacter/isolation & purification , beta-Lactamases/isolation & purification , Acinetobacter Infections/microbiology , Anti-Bacterial Agents/therapeutic use , beta-Lactamases/genetics , Brazil , Acinetobacter Infections/drug therapy , Microbial Sensitivity Tests
14.
Braz. j. microbiol ; 49(4): 914-918, Oct.-Dec. 2018. tab
Article in English | LILACS | ID: biblio-974286

ABSTRACT

ABSTRACT The global emergence of carbapenemases led to the need of developing new methods for their rapid detection. The aim of this study was to evaluate the performance of the rapid tests for carbapenemase-producing and non-producing Enterobacteriaceae. Carbapenem non-susceptible Enterobacteriaceae from a surveillance study submitted to a multiplex real time PCR for carbapenemase detection were included in this study. The isolates were subjected to the rapid phenotypic tests Carba NP, Blue-Carba and Carbapenem Inactivation Method (CIM). A total of 83 carbapenemase-producing (43) and non-producing (40) isolates were included in the study. The sensitivity/specificity were 62.7%/97.5%, 95.3%/100%, and 74.4%/97.5% for Carba NP, Blue-Carba and CIM, respectively. Both Carba NP and Blue-Carba presented their final results after 75 min of incubation; the final results for CIM were obtained only after 8 h. Failure to detect OXA-370 carbapenemase was the main problem for Carba NP and CIM assays. As the Blue-Carba presented the highest sensitivity, it can be considered the best screening test. Conversely, CIM might be the easiest to perform, as it does not require special reagents. The early detection of carbapenemases aids to establish infection control measures and prevent carbapenemases to spread reducing the risk of healthcare associated infections and therapeutic failure.


Subject(s)
Humans , Bacterial Proteins/analysis , beta-Lactamases/analysis , Enterobacteriaceae/enzymology , Enterobacteriaceae Infections/microbiology , Enzyme Assays/methods , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , beta-Lactamases/genetics , beta-Lactamases/metabolism , Brazil , Carbapenems/pharmacology , Polymerase Chain Reaction , Sensitivity and Specificity , Enterobacteriaceae/isolation & purification , Enterobacteriaceae/drug effects , Enterobacteriaceae/genetics , Enterobacteriaceae Infections/diagnosis , Anti-Bacterial Agents/pharmacology
16.
Braz. j. microbiol ; 49(3): 569-574, July-Sept. 2018. tab, graf
Article in English | LILACS | ID: biblio-951794

ABSTRACT

Abstract Multidrug-resistant microorganisms are of great concern to public health. Genetic mobile elements, such as plasmids, are among the most relevant mechanisms by which bacteria achieve this resistance. We obtained an Escherichia coli strain CM6, isolated from cattle presenting severe diarrheic symptoms in the State of Querétaro, Mexico. It was found to contain a 70 kb plasmid (pMEX01) with a high similarity to the pHK01-like plasmids that were previously identified and described in Hong Kong. Analysis of the pMEX01 sequence revealed the presence of a blaCTX-M-14 gene, which is responsible for conferring resistance to multiple β-lactam antibiotics. Several genes putatively involved in the conjugative transfer were also identified on the plasmid. The strain CM6 is of high epidemiological concern because it not only displays resistance to multiple β-lactam antibiotics but also to other kinds of antibiotics.


Subject(s)
Animals , Cattle , Plasmids/genetics , Cattle Diseases/microbiology , Drug Resistance, Bacterial , beta-Lactams/pharmacology , Escherichia coli/drug effects , Escherichia coli/genetics , Escherichia coli Infections/veterinary , Anti-Bacterial Agents/pharmacology , Plasmids/metabolism , beta-Lactamases/genetics , beta-Lactamases/metabolism , Microbial Sensitivity Tests , Escherichia coli Proteins/genetics , Escherichia coli Proteins/metabolism , Escherichia coli/metabolism , Escherichia coli Infections/microbiology , Mexico
17.
Braz. j. microbiol ; 49(3): 471-480, July-Sept. 2018. tab, graf
Article in English | LILACS | ID: biblio-951821

ABSTRACT

Abstract Escalating burden of antibiotic resistance that has reached new heights present a grave concern to mankind. As the problem is no longer confined to clinics, we hereby report identification of a pandrug resistant Escherichia coli isolate from heavily polluted Delhi stretch of river Yamuna, India. E. coli MRC11 was found sensitive only to tobramycin against 21 antibiotics tested, with minimum inhibitory concentration values >256 µg/mL for amoxicillin, carbenicillin, aztreonam, ceftazidime and cefotaxime. Addition of certain heavy metals at higher concentrations were ineffective in increasing susceptibility of E. coli MRC11 to antibiotics. Withstanding sub-optimal concentration of cefotaxime (10 µg/mL) and mercuric chloride (2 µg/mL), and also resistance to their combinatorial use, indicates better adaptability in heavily polluted environment through clustering and expression of resistance genes. Interestingly, E. coli MRC11 harbours two different variants of blaTEM (blaTEM-116 and blaTEM-1 with and without extended-spectrum activity, respectively), in addition to mer operon (merB, merP and merT) genes. Studies employing conjugation, confirmed localization of blaTEM-116, merP and merT genes on the conjugative plasmid. Understanding potentialities of such isolates will help in determining risk factors attributing pandrug resistance and strengthening strategic development of new and effective antimicrobial agents.


Subject(s)
Metals, Heavy/pharmacology , Drug Resistance, Multiple, Bacterial , Rivers/microbiology , Escherichia coli/drug effects , Anti-Bacterial Agents/pharmacology , Operon , beta-Lactamases/genetics , beta-Lactamases/metabolism , Microbial Sensitivity Tests , Escherichia coli Proteins/genetics , Escherichia coli Proteins/metabolism , Escherichia coli/isolation & purification , Escherichia coli/enzymology , Escherichia coli/genetics , India
18.
Braz. j. microbiol ; 49(2): 401-406, Apr.-June 2018. tab, graf
Article in English | LILACS | ID: biblio-889246

ABSTRACT

Abstract Introduction The present study attempts to examine the microbial profile and antibiotic susceptibility of diabetic foot infections in the intensive care unit of a tertiary referral centre for diabetic foot. As part of the study, we also attempted to find the prevalence of blaNDM-like gene among carbapenem-resistant gram negative infections. Methodology A prospective study of 261 patients with diabetic foot infections was performed during the period between January 2014 and June 2014. Results A total of 289 isolates were obtained from 178 tissue samples from 261 patients, 156 (59.7%) males and 105 (40.2%) females, with a mean age of 58 years (-15 years), having diabetic foot infection. No growth was seen in thirty eight (17.6%) tissue samples. Out of the total samples, 44.3% were monomicrobial and 55.7% were polymicrobial. Gram negative pathogens were predominant (58.5%). Seven of the total isolates were fungal; 0.7% showed pure fungal growth and 1.7% were mixed, grown along with some bacteria. The most frequently isolated bacteria were Staphylococcus aureus (26.9%), followed by Pseudomonas aeruginosa (20.9%). Of the 58.5% gram negative pathogens, 16.5% were Enterobacteriaceae resistant to carbapenems. Among these isolates, 4 (25%) were positive for blaNDM-like gene. Among the rest, 18.6% were carbapenem-resistant Pseudomonas, among which 4 (36.3%) were blaNDM. Among the Staphylococci, 23.7% were methicillin-resistant Staphylococcus aureus. Conclusions Our results support the recent view that gram negative organisms, depending on the geographical location, may be predominant in DFIs. There is an increase in multidrug-resistant pathogens, especially carbapenem resistance and this is creeping rapidly. We need to be more judicious while using empiric antibiotics.


Subject(s)
Humans , Male , Female , Adult , Middle Aged , Aged , Bacterial Infections/epidemiology , Diabetic Foot/complications , Gram-Negative Bacteria/isolation & purification , Gram-Positive Bacteria/isolation & purification , Mycoses/epidemiology , Bacterial Infections/microbiology , Bacterial Proteins/genetics , beta-Lactamases/genetics , Coinfection/epidemiology , Coinfection/microbiology , Gram-Negative Bacteria/classification , Gram-Positive Bacteria/classification , India , Methicillin Resistance , Microbial Sensitivity Tests , Mycoses/microbiology , Prevalence , Prospective Studies , Tertiary Care Centers
19.
Rev. chil. infectol ; 35(2): 147-154, abr. 2018. tab, graf
Article in Spanish | LILACS | ID: biblio-959424

ABSTRACT

Resumen Introducción: La resistencia de enterobacterias a quinolonas se ha difundido por el mundo, fenómeno presente también en Venezuela. El mecanismo de esta resistencia pudiera estar mediado por genes incluidos en el cromosoma bacteriano o transmitirse en el interior de plásmidos. Objetivo: Evaluar la resistencia a quino-lonas, codificada por genes qnr, presentes en cepas de enterobacterias, aisladas en el Hospital Universitario de Cumaná, Venezuela. Métodos: A las cepas obtenidas se les realizaron pruebas de susceptibilidad antimicrobiana a quinolonas, β-lactámicos y aminoglucósidos. La presencia del gen qnr se determinó por RPC. Las enterobacterias portadoras del gen qnr fueron sometidas al proceso de conjugación bacteriana para comprobar su capacidad de transferencia. A las transconjugantes obtenidas se les realizó pruebas de susceptibilidad antimicrobiana y RPC para comprobar la transferencia de los genes. Resultados: Se encontraron elevados porcentajes de resistencia antimicrobiana a quinolonas y betalactámicos. El 33,6% de las cepas eran portadoras del gen qnrB, y 0,9% del gen qnrA. Se obtuvieron 23 cepas transconjugantes; de éstas, 20 portaban el gen qnrB, no se observó la presencia de qnrA. Discusión: En conclusión, el elevado porcentaje de genes qnr encontrado en las enterobacterias aisladas, y comprobada la presencia de éstos en plásmidos transferibles, complica la aplicación de tratamientos basados en quinolonas y fluoroquinolonas, por lo que es recomendable el uso racional de estos antimicrobianos, y proponer la rotación de la terapia antimicrobiana, a fin de evitar la selección de cepas resistentes.


Background: Enterobacteria resistant to quinolones is increasing worldwide, including Venezuela. The mechanism for this resistance could be due to genes included in the chromosome or in transmissible plasmids. Aim: To evaluate the resistance to quinolones, coded by qnr genes present in enterobacteria species, isolated in the University Hospital of Cumana, Venezuela. Methods: Antimicrobial susceptibility tests to quinolones, beta-lactams and aminoglycosides were carried out to all the isolates. The presence of qnr genes were determined by PCR. The isolates carrying the qnr genes were used for bacterial conjugation tests to determine the presence of transferable plasmids. Antimicrobial susceptibility tests and PCR were carried out in the transconjugants to verify the transfer of the genes. Results: High levels of antimicrobial resistance to quinolones and beta-lactams were found among the isolates. We found that 33.6% of the isolates carry the qnrB gene and 0.9% qnr A gene. Of the 23 transconjugants, 20 showed to have qnrB gene, but none qnrA. Discussion: We concluded that the high frequency of qnr genes found in the enterobacteria isolates and their presence on transferable plasmids, complicate the use of quinolones for the treatment of bacterial infections, thus, a treatment plan should be designed with the rational use and the rotation of different types of antimicrobials, in order to avoid the selection of increasingly resistant strains.


Subject(s)
Plasmids , Quinolones/pharmacology , beta-Lactam Resistance/genetics , Drug Resistance, Bacterial/genetics , Enterobacteriaceae/genetics , Enterobacteriaceae Infections/genetics , Gram-Negative Bacteria/genetics , Anti-Bacterial Agents/pharmacology , Venezuela , beta-Lactamases/genetics , DNA, Bacterial/genetics , Microbial Sensitivity Tests , Polymerase Chain Reaction , Sequence Analysis, DNA , Escherichia coli Proteins , Enterobacteriaceae/isolation & purification , Enterobacteriaceae Infections/microbiology , Genes, Bacterial , Gram-Negative Bacteria/classification , Hospitals, University
20.
Rev. Soc. Bras. Med. Trop ; 51(1): 88-93, Jan.-Feb. 2018. tab
Article in English | LILACS | ID: biblio-1041448

ABSTRACT

Abstract INTRODUCTION: Here, we determined the genes encoding antibiotic resistance enzymes and virulence factors and evaluated the genetic relationship between Enterobacter spp. isolated from different clinical samples. METHODS: A total of 57 clinical isolates of Enterobacter spp. were tested for the production of extended-spectrum β-lactamases (ESBLs), carbapenemase, and AmpC using phenotypic and genotypic methods. RESULTS: The most common ESBLs and AmpC β-lactamases were bla TEM (63.3%) and bla EBC (57.7%), respectively. The most prevalent virulence gene was rpos (87.7%). The random amplified polymorphic DNA (RAPD) patterns of strains were genetically unrelated. CONCLUSIONS: RAPD polymerase chain reaction analysis revealed high genetic diversity among isolates.


Subject(s)
Humans , Bacterial Proteins/biosynthesis , Bacterial Proteins/genetics , beta-Lactamases/genetics , Escherichia coli/drug effects , Feces/microbiology , Anti-Bacterial Agents/pharmacology , Phenotype , Bacterial Proteins/drug effects , beta-Lactamases/biosynthesis , Polymerase Chain Reaction , Clone Cells , Drug Resistance, Multiple, Bacterial , beta-Lactams/adverse effects , Escherichia coli/enzymology , Escherichia coli/genetics , Disk Diffusion Antimicrobial Tests , Genotype , Iran
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