Virulence characterization of Klebsiella pneumoniae and its relation with ESBL and AmpC beta-lactamase associated resistance

Background and Objectives: Trend analysis reveals that Klebsiella pneumoniae has witnessed a steep enhancement in the antibiotic resistance and virulence over the last few decades. The present investigation aimed at a comprehensive approach investigating antibiotic susceptibility including, extended spectrum beta-lactamase (ESBL) and AmpC β-lactamase (AmpC) resistance and the prevalence of virulence genes among the K. pneumoniae isolates. Materials and Methods: Sixty-one K. pneumoniae isolates were obtained from various clinical infections. Antimicrobial susceptibility was performed by disk diffusion method. The Mast® D68C test detected the presence of ESBLs and AmpCs phenotypically, and later presence of ESBL and AmpC genes was observed by polymerase chain reaction (PCR). Multi- plex-PCR was performed to investigate various virulence genes. CMY-2 Results: Amongst 61 K. pneumoniae isolates, 59% were observed as ESBL and 14.7% as AmpC producers. All ESBL CTX-M-15 producers were positive for bla CTX-M-15 , while bla CTX-M-14 was observed in 54.1% isolates. The frequency of AmpC genes was CMY-2 as follows: bla CMY-2 (60.7%) and bla DHA-1 (34.4%). The most frequent virulence genes were those encoding enterobactin and DHA-1 lipopolysaccharide. Presence of mrkD was associated with bla CMY-2 DHA-1 gene, while bla significantly (p≤0.05) correlated DHA-1 with the presence of iutA and rmpA virulence genes. bla positive isolates had urine as a significant source, while bla positive isolates were mainly collected from wound exudates (p≤0.05). Conclusion: Our results highlight that ESBL and AmpC production along with a plethora of virulence trait on K. pneumoni- ae should be adequately considered to assess its pathogenesis and antibiotic resistance.

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Prevalence of Escherichia coli and Klebsiella pneumoniae, Producing Extended-Spectrum Beta-Lactamase (ESBLs) from Clinical Specimen in Khuzestan, Iran

Gene Cell and Tissue ◽

10.5812/gct.112377 ◽

2021 ◽

Vol In Press (In Press) ◽

Author(s):

Sahar Besharati Zadeh ◽

Pegah Shakib ◽

Mohammad Reza Zolfaghari ◽

Ahmad Farajzadeh Sheikh

Keyword(s):

Escherichia Coli ◽

Antibiotic Resistance ◽

Klebsiella Pneumoniae ◽

Clinical Specimen ◽

Diffusion Method ◽

Beta Lactamase ◽

Extended Spectrum Beta Lactamase ◽

E Coli ◽

Extended Spectrum ◽

Sensitivity Pattern

Background: A major problem in the treatment of the infectious diseases healthcare centers is extended-spectrum beta-lactamase (ESBL)-producing bacteria. Objectives: The aim of present study was to identify the antibiotic sensitivity pattern and prevalence of the blaCTX, blaTEM, and blaSHV genes in Escherichia coli and Klebsiella pneumoniae strains. Methods: In this study, E. coli and K. pneumoniae specimens were collected in Shushtar hospitals, Khuzestan (southwest Iran), from March to October 2015. Sensitivity antibiotic pattern performed by disc diffusion method. Double disc synergy test (DDST) done for identifying ESBLs isolates and PCR for blaTEM, blaSHV, and blaCTX-M genes. Results: One hundred E. coli and 30 K. pneumoniae isolates were collected from different specimens. The highest rates of antibiotic resistance related to cefotaxime and aztreonam in E. coli and K. pneumoniae. ESBL-harboring K. pneumoniae and E. coli were 13.5 and 28%, respectively. Overall, bla TEM was the most prevalent ESBL gene. Conclusions: In this study, the rate of antibiotic resistance was high, and due to the carrying of coding genes on mobile genetic elements and the ability of these elements to carry genes that create resistance to other antibiotic families, identification and isolation of these isolates are essential to find effective antibiotics and eliminate the infection.

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Evaluation of extended spectrum beta lactamase enzymes prevalence in clinical isolates of Escherichia coli

Microbiology Research ◽

10.4081/mr.2011.e8 ◽

2011 ◽

Vol 2 (1) ◽

pp. 8

Author(s):

Ronak Bakhtiari ◽

Jalil Fallah Mehrabadi ◽

Hedroosha Molla Agamirzaei ◽

Ailar Sabbaghi ◽

Mohammad Mehdi Soltan Dallal

Keyword(s):

Escherichia Coli ◽

Disk Diffusion ◽

Confirmatory Test ◽

Diffusion Method ◽

Multi Drug Resistance ◽

Beta Lactamase ◽

Disk Diffusion Method ◽

Extended Spectrum Beta Lactamase ◽

E Coli ◽

Extended Spectrum

Resistance to b-lactam antibiotics by gramnegative bacteria, especially Escherichia coli (E. coli), is a major public health issue worldwide. The predominant resistance mechanism in gram negative bacteria particularly E. coli is via the production of extended spectrum beta lactamase (ESBLs) enzymes. In recent years, the prevalence of b-lactamase producing organisms is increased and identification of these isolates by using disk diffusion method and no-one else is not satisfactory. So, this investigation focused on evaluating the prevalence of ESBL enzymes by disk diffusion method and confirmatory test (Combined Disk). Five hundred clinical samples were collected and 200 E. coli isolates were detected by standard biochemical tests. To performing initial screening of ESBLs was used from Disk diffusion method on E. coli isolates. A confirmation test (Combined Disk method) was performed on isolates of resistant to cephalosporin's indicators. Up to 70% isolates exhibited the Multi Drug Resistance phenotype. In Disk diffusion method, 128(64%) E. coli isolates which resistant to ceftazidime and cefotaxime while in Combined Disk, among 128 screened isolates, 115 (89.8%) isolates were detected as ESBLs producers. This survey indicate beta lactamase enzymes are playing a significant role in antibiotic resistance and correct detection of them in phenotypic test by using disk diffusion and combined Disk is essential for accurate recognition of ESBLs.

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Presence of different beta-lactamase classes among clinical isolates of Pseudomonas aeruginosa expressing AmpC beta-lactamase enzyme

The Journal of Infection in Developing Countries ◽

10.3855/jidc.497 ◽

2010 ◽

Vol 4 (04) ◽

pp. 239-242 ◽

Cited By ~ 16

Author(s):

Supriya Upadhyay ◽

Malay Ranjan Sen ◽

Amitabha Bhattacharjee

Keyword(s):

Pseudomonas Aeruginosa ◽

Treatment Options ◽

Clinical Isolates ◽

Diffusion Method ◽

Beta Lactamase ◽

Beta Lactam ◽

Disk Diffusion Method ◽

Extended Spectrum Beta Lactamase ◽

Extended Spectrum ◽

Enzyme Detection

Introduction: Infections caused by Pseudomonas aeruginosa are difficult to treat as the majority of isolates exhibit varying degrees of beta-lactamase mediated resistance to most of the beta-lactam antibiotics. It is also not unusual to find a single isolate that expresses multiple β-lactamase enzymes, further complicating the treatment options. Thus the present study was designed to investigate the coexistence of different beta-lactamase enzymes in clinical isolates of P. aeruginosa. Methodology: A total of 202 clinical isolates of P. aeruginosa were tested for the presence of AmpC beta-lactamase, extended spectrum beta-lactamase (ESBL) and metallo beta-lactamase (MBL) enzyme. Detection of AmpC beta-lactamase was performed by disk antagonism test and a modified three-dimensional method, whereas detection of ESBL was done by the combined disk diffusion method per Clinical and Laboratory Standards Institute (CLSI) guidelines and MBL were detected by the Imipenem EDTA disk potentiation test. Results: A total of 120 (59.4%) isolates were confirmed to be positive for AmpC beta-lactamase. Among them, 14 strains (7%) were inducible AmpC producers. Co-production of AmpC along with extended spectrum beta-lactamase and metallo beta-lactamase was reported in 3.3% and 46.6% isolates respectively. Conclusion: The study emphasizes the high prevalence of multidrug resistant P. aeruginosa producing beta-lactamase enzymes of diverse mechanisms. Thus proper antibiotic policy and measures to restrict the indiscriminative use of cephalosporins and carbapenems should be taken to minimize the emergence of this multiple beta-lactamase producing pathogens.

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Extended Spectrum Beta-Lactamase Production in Uropathogens Isolated from Hospitalized Patients with Chronic Pyelonephritis

The Open Urology & Nephrology Journal ◽

10.2174/1874303x01508010071 ◽

2015 ◽

Vol 8 (1) ◽

pp. 71-75 ◽

Cited By ~ 2

Author(s):

Olga I Chub ◽

Aleksandr V Bilchenko ◽

Igor Khalin

Keyword(s):

Cross Sectional Study ◽

Hospitalized Patients ◽

Chronic Pyelonephritis ◽

Diffusion Method ◽

Beta Lactamase ◽

Disk Diffusion Method ◽

Cross Sectional ◽

Extended Spectrum Beta Lactamase ◽

Extended Spectrum ◽

Tract Infections

Background : Increased multidrug resistance of extended-spectrum beta-lactamases (ESBLs) compromises the efficacy of treatment of urinary tract infections. Objective : The objective of this study is to determine the prevalence of ESBL-producing uropathogens from hospitalized patients with chronic pyelonephritis and to identify the presence of genes involved in the resistance. Methods : A cross-sectional study of 105 patients with chronic pyelonephritis, treated in Kharkiv City Clinical Emergency Hospital, Ukraine was carried. Bacterial isolates were collected, antimicrobial susceptibility of isolates was determined by the Kirby Bauer disk diffusion method and screening for the presence of blaSHV, blaTEM, blaCTX-M ESBL genes was performed by polymerase chain reaction. Results : 84 (80%) patients had positive urine cultures. Eschеrichia coli wаs the most common microorganism isolated. Among them, 29 (25.2%) were found to be ESBL producers. Out of 53 E. coli isolates, 10 (18.9%), 4 (7.5%) and 6 (11.3%) were identified to carry bla(TEM), bla(SHV) and bla(CTX-M) beta-lactamase genes, respectively. The highest resistance was observed against ampicillin (75.9%), ciprofloxacin (48.3%), levofloxacin (41.4%) and gentamicin (41.4%). Beside this, only meropenem (96.6% susceptibility), nitroxolinum (86.2%) and fosfomycin (72.4%) exhibited a good enough activity against ESBLs-producing urinary strains. Conclusion : Isоlation and detеction of ESBL-prоducing strаins are еssential fоr the sеlection оf the mоst effеctive antibiоtic for the empiric trеatment.

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Prevalence of Virulence Genes and Drug Resistance Profiles of Pseudomonas aeruginosa Isolated From Clinical Specimens

Jundishapur Journal of Microbiology ◽

10.5812/jjm.118452 ◽

2021 ◽

Vol 14 (8) ◽

Author(s):

Seyed Ali Bazghandi ◽

Mohsen Arzanlou ◽

Hadi Peeridogaheh ◽

Hamid Vaez ◽

Amirhossein Sahebkar ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Drug Resistance ◽

Antibiotic Resistance ◽

Virulence Genes ◽

Virulence Gene ◽

Clinical Isolates ◽

Diffusion Method ◽

Disk Diffusion Method ◽

Clinical Specimens ◽

Resistance Rates

Background: Drug resistance and virulence genes are two key factors for the colonization of Pseudomonas aeruginosa in settings with high antibiotic pressure, such as hospitals, and the development of hospital-acquired infections. Objectives: The objective of this study was to investigate the prevalence of drug resistance and virulence gene profiles in clinical isolates of P. aeruginosa in Ardabil, Iran. Methods: A total of 84 P. aeruginosa isolates were collected from clinical specimens of Ardabil hospitals and confirmed using laboratory standard tests. The disk diffusion method was used for antibiotic susceptibility testing and polymerase chain reaction (PCR) for the identification of P. aeruginosa virulence genes. Results: The highest and the lowest antibiotic resistance rates of P. aeruginosa strains were against ticarcillin-clavulanate (94%) and doripenem (33.3%), respectively. In addition, the frequency of multidrug-resistant (MDR) P. aeruginosa was 55.9%. The prevalence of virulence factor genes was as follows: algD 84.5%, lasB 86.9%, plcH 86.9%, plcN 86.9%, exoU 56%, exoS 51.2%, toxA 81%, nan1 13.1%, and pilB 33.3%. A significant association was observed between resistance to some antibiotics and the prevalence of virulence genes in P. aeruginosa. Conclusions: Our results revealed a high prevalence of antibiotic resistance, especially MDR, and virulence-associated genes in clinical isolates of P. aeruginosa in Ardabil hospitals. Owing to the low resistance rates against doripenem, gentamicin, and tobramycin, these antibiotics are recommended for the treatment of infections caused by highly resistant and virulent P. aeruginosa strains.

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Vancomycin and high-level aminoglycoside resistance in Enterococcus species

Microbiology Research ◽

10.4081/mr.2016.6441 ◽

2016 ◽

Vol 7 (1) ◽

Cited By ~ 1

Author(s):

Seyda Ozarslan Kurtgoz ◽

Burcin Ozer ◽

Melek Inci ◽

Nizami Duran ◽

Erkan Yula

Keyword(s):

Vancomycin Resistance ◽

Automated System ◽

Diffusion Method ◽

Beta Lactamase ◽

Aminoglycoside Resistance ◽

Disk Diffusion Method ◽

Gradient Diffusion ◽

Gentamicin Resistance ◽

Polymerase Chain ◽

High Level

The aim of the study was to investigate vancomycin and high-level aminoglycoside resistance (HLAR) in Enterococcus species by phenotypic and genotypic methods. A hundred Enterococcus strains were included in the study. Antimicrobial susceptibilities of strains were investigated by automated system, betalactamase production was investigated by nitrocefin disks, vancomycin resistance and HLAR were investigated by gradient diffusion method (GDM) and disk diffusion method, respectively. For detection of vancomycin and high-level gentamicin resistance (HLGR) genes, polymerase chain reaction was used. Teicoplanin linezolid, vancomycin, ampicillin, penicillin are the most susceptible antibiotics and strains were detected not to produce beta lactamase. Vancomycin resistance was detected in ten isolates by automated system and in only five isolates by GDM. Five isolates carrying VanA gene were determined. The ratio of HLGR and high-level streptomycin resistance was found 40 and 63% respectively. aac (6’)-1eaph (2’’)-1a gene was detected in 58% of strains. E. faecium strains were found more resistant to the antibiotics than the other species. Beta lactamase was detected in none of strains. The automated system detected vancomycin resistance in more strains than GDM. Therefore it is concluded that strains, which were detected to be resistant to vancomycin, should be confirmed by GDM. The ratio of VanA gene in strains is consistent with other studies. The HLAR ratio was found in about half of strains. The ratio of aac(6’)-1e-aph(2’’)-1a gene, which is the most reported gene in our country and other countries and one of the HLGR genes investigated in our study, was detected 58%.

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Virulence-Associated Genes and Antimicrobial Resistance of Aeromonas hydrophila Isolates from Animal, Food, and Human Sources in Brazil

BioMed Research International ◽

10.1155/2020/1052607 ◽

2020 ◽

Vol 2020 ◽

pp. 1-8

Author(s):

Emily Moraes Roges ◽

Verônica Dias Gonçalves ◽

Maira Duarte Cardoso ◽

Marcia Lima Festivo ◽

Salvatore Siciliano ◽

...

Keyword(s):

Antimicrobial Resistance ◽

Aeromonas Hydrophila ◽

Pathogenic Bacteria ◽

Virulence Genes ◽

Animal Health ◽

Diffusion Method ◽

Aquatic Environments ◽

Disk Diffusion Method ◽

Polymerase Chain ◽

Human Source

Aeromonads are natural inhabitants of aquatic environments and may be associated with various human or animal diseases. Its pathogenicity is complex and multifactorial and is associated with many virulence factors. In this study, 110 selected Aeromonas hydrophila isolates isolated from food, animals, and human clinical material from 2010 to 2015 were analyzed. Antimicrobial susceptibility testing was performed by the disk diffusion method, and polymerase chain reaction was conducted to investigate the virulence genes hemolysin (hlyA), cytotoxic enterotoxin (act), heat-labile cytotonic enterotoxin (alt), aerolysin (aerA), and DNase-nuclease (exu). At least 92.7% of the isolates had one of the investigated virulence genes. Twenty different virulence profiles among the isolates were recognized, and the five investigated virulence genes were observed in four isolates. Human source isolates showed greater diversity than food and animal sources. Antimicrobial resistance was observed in 46.4% of the isolates, and multidrug resistance was detected in 3.6% of the isolates. Among the 120 isolates, 45% were resistant to cefoxitin; 23.5% to nalidixic acid; 16.6% to tetracycline; 13.7% to cefotaxime and imipenem; 11.8% to ceftazidime; 5.9% to amikacin, gentamicin, and sulfamethoxazole-trimethoprim; and 3.9% to ciprofloxacin and nitrofurantoin. Overall, the findings of our study indicated the presence of virulence genes and that antimicrobial resistance in A. hydrophila isolates in this study is compatible with potentially pathogenic bacteria. This information will allow us to recognize the potential risk through circulating isolates in animal health and public health and the spread through the food chain offering subsidies for appropriate sanitary actions.

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Prevalence of Plasmid-Mediated Quinolone Resistance Genes among Extended-Spectrumβ-Lactamase-ProducingKlebsiella pneumoniaeHuman Isolates in Iran

Journal of Pathogens ◽

10.1155/2015/434391 ◽

2015 ◽

Vol 2015 ◽

pp. 1-7 ◽

Cited By ~ 15

Author(s):

Ehsaneh Shams ◽

Farzaneh Firoozeh ◽

Rezvan Moniri ◽

Mohammad Zibaei

Keyword(s):

Klebsiella Pneumoniae ◽

Resistance Genes ◽

High Frequency ◽

Quinolone Resistance ◽

Confirmatory Test ◽

Diffusion Method ◽

Disk Diffusion Method ◽

Pcr Products ◽

Pcr Method

The purpose of this study was to determine the prevalence and molecular characterization of plasmid-mediated quinolone resistance (PMQR) genes (qnrA, qnrB, qnrS, aac(6′)-Ib-cr, andqepA) among ESBL-producingKlebsiella pneumoniaeisolates in Kashan, Iran. A total of 185K. pneumoniaeisolates were tested for quinolone resistance and ESBL-producing using the disk diffusion method and double disk synergy (DDST) confirmatory test. ESBL-producing strains were further evaluated for theblaCTX-Mgenes. The PCR method was used to show presence of plasmid-mediated quinolone resistance genes and the purified PCR products were sequenced. Eighty-seven ESBL-producing strains were identified by DDST confirmatory test and majority (70, 80.5%) of which carriedblaCTX-Mgenes including CTX-M-1 (60%), CTX-M-2 (42.9%), and CTX-M-9 (34.3%). Seventy-seven ESBL-producingK. pneumoniaeisolates harbored PMQR genes, which mostly consisted ofaac(6′)-Ib-cr(70.1%) andqnrB(46.0%), followed byqnrS(5.7%). Among the 77 PMQR-positive isolates, 27 (35.1%) and 1 (1.3%) carried 2 and 3 different PMQR genes, respectively. However,qnrAandqepAwere not found in any isolate. Our results highlight high ESBL occurrence with CTX-M type and high frequency of plasmid-mediated quinolone resistance genes among ESBL-producingK. pneumoniaeisolates in Kashan.

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Antibiotic resistance and virulence genes of extraintestinal pathogenic Escherichia coli from tropical estuary, south India

The Journal of Infection in Developing Countries ◽

10.3855/jidc.5627 ◽

2015 ◽

Vol 9 (05) ◽

pp. 496-504 ◽

Cited By ~ 1

Author(s):

Divya Sukumaran ◽

Abdulla A Mohamed Hatha

Keyword(s):

Escherichia Coli ◽

Antibiotic Resistance ◽

Multidrug Resistance ◽

Virulence Factor ◽

Virulence Genes ◽

Antimicrobial Agents ◽

Diffusion Method ◽

Disk Diffusion Method ◽

E Coli ◽

Virulence Factor Genes

Introduction: Escherichia coli strains can cause a variety of intestinal and extraintestinal diseases. Extraintestinal pathogenic E. coli (ExPEC) strains have the ability to cause severe extraintestinal infections. Multidrug resistance among ExPEC could complicate human infections. Methodology: Escherichia coli strains were isolated during the period of January 2010 to December 2012 from five different stations set at Cochin estuary. Susceptibility testing was determined by the disk-diffusion method using nine different antimicrobial agents. A total of 155 strains of Escherichia coli were screened for the presence of virulence factor genes including papAH, papC, sfa/focDE, iutA,and kpsMT II associated with ExPEC. Results: Among the 155 E. coli isolates, 26 (16.77%), carried two or more virulence genes typical of ExPEC. Furthermore, 19.23% of the ExPEC isolates with multidrug resistance were identified to belong to phylogenetic groups B2 and D. Statistically significant association of iutA gene in ExPEC was found with papC (p < 0.001) and kpsMT II (p < 0.001) genes. ExPEC isolates were mainly resistant to ampicillin (23.07%), tetracycline (19.23%), co-trimoxazole (15.38%), and cefotaxime (15.38%). The adhesion genes papAH and sfa/focDE were positively associated with resistance to gentamicin, chloramphenicol, and cefotaxime (p < 0.05). Conclusions: Co-occurrence of virulence factor genes with antibiotic resistance among ExPEC poses considerable threat to those who use this aquatic system for a living and for recreation.

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Investigation of Antibiotic Resistance and Biofilm Formation in Clinical Isolates of Klebsiella pneumoniae

International Journal of Microbiology ◽

10.1155/2021/5573388 ◽

2021 ◽

Vol 2021 ◽

pp. 1-6

Author(s):

Kiana Karimi ◽

Omid Zarei ◽

Parinaz Sedighi ◽

Mohammad Taheri ◽

Amin Doosti-Irani ◽

...

Keyword(s):

Antibiotic Resistance ◽

Klebsiella Pneumoniae ◽

Biofilm Formation ◽

Diffusion Method ◽

Clinical Samples ◽

Resistance Pattern ◽

Chi Square ◽

Disk Diffusion Method ◽

High Level ◽

Tract Infections

Aim. Klebsiella pneumoniae (K. pneumoniae) is an encapsulated Gram-negative bacterium that can lead to 14–20% of nosocomial infections. The ability of biofilm formation in this bacterium decreases the host immune response and antibiotic efficacy. This may impose a huge impact on patients and healthcare settings. This study aimed to evaluate the antibiotic resistance pattern and biofilm formation in K. pneumoniae strains isolated from two major Hamadan hospitals, west of Iran. Methods. A total of 83 K. pneumoniae strains were isolated from clinical samples of patients in different wards of Hamadan hospitals from September 2018 to March 2019. Determination of antimicrobial susceptibility was performed using the disk diffusion method. Biofilm formation was evaluated by the crystal violet method. Data were analyzed by the SPSS software and chi-square test. Results. The results showed that clinical samples included 18 urinary tract samples (22%), 6 wound samples (7%), 6 blood samples (7%), 17 tracheal tube aspiration samples (20%), 32 throat cultures (38%), 2 sputum samples (2.5%), and 2 abscess drain cultures (2.5%). High-level resistance to cefotaxime was detected in 92%, and all of isolates were susceptible to colistin. Biofilm formation was seen in 62 (75%) isolates. Strong biofilm formation was observed in 17 (20%) strains. A significant correlation was seen between biofilm formation and antibiotic resistance ( P value <0.05). Conclusion. Our findings emphasize the need for proper diagnosis, control, and treatment of infections caused by K. pneumoniae especially in respiratory tract infections due to the strong biofilm formation and high antibiotic resistance in these strains.

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