Prevalence and Distribution of Resistance and Enterotoxins/Enterotoxin-likes Genes in Different Clinical Isolates of Coagulase-negative Staphylococcus

Abstract Background CoNS serve as a major reservoir for genes facilitating the evolution of S. aureus as a successful pathogen. The present study aimed to determine the occurrence of genes conferring resistance to fluoroquinolone, determining of the prevalence of insertion sequence elements IS256 and IS257 and different superantigenes (SAgs) among CoNS isolates obtained from various clinical sources. Materials and Methods The current study conducted on a total of 91 CoNS species isolated from clinical specimens in Hamadan hospitals in western Iran in 2017-19. The Antimicrobial susceptibility testing was performed using disk diffusion method and the presence of the IS256 and IS257, genes conferring resistance to fluoroquinolone and enterotoxins/enterotoxin-likes encoding genes were investigated by PCR method. Results Among genes encoding classic enterotoxins, sec was the most frequent which was carried by 48.4% of isolates, followed by seb in 27.5%. None of the CoNS isolates were found to be positive to enterotoxin-like encoding genes. Among the 11 CoNS isolates that have shown phenotypically resistant to levofloxacin, 9 isolates (81.8%) with gyrB , 8 isolates (72.7%) with gyrA, 8 isolates (72.7%) with grlB and 7 isolates (63.6%) with grlA were identified. The IS256 and IS257 were identified in 31.8% and 74.7% of CoNS isolates. The results of statistical analysis showed a significant association between the occurrence of SEs encoding genes and antimicrobial resistance. Conclusion Antimicrobial resistant determinants and staphylococcus enterotoxins (SEs) are co-present in clinical CoNS isolates that confer selective advantage for colonization and survival in hospital settings. The coexistence of insertion elements and antibiotic resistance indicate their role in pathogenesis and infectious disease.

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Prevalence and distribution of resistance and enterotoxins/enterotoxin-like genes in different clinical isolates of coagulase-negative Staphylococcus

European Journal of Medical Research ◽

10.1186/s40001-020-00447-w ◽

2020 ◽

Vol 25 (1) ◽

Author(s):

Mona Nasaj ◽

Zahra Saeidi ◽

Hamed Tahmasebi ◽

Sanaz Dehbashi ◽

Mohammad Reza Arabestani

Keyword(s):

Selective Advantage ◽

Diffusion Method ◽

Coagulase Negative Staphylococcus ◽

Disk Diffusion Method ◽

Genes Encoding ◽

Sequence Elements ◽

Insertion Elements ◽

Pcr Method ◽

Polymerase Chain ◽

Encoding Genes

Abstract Background Coagulase-negative staphylococcus (CoNS) is considered to be the major reservoirs for genes facilitating the evolution of S. aureus as a successful pathogen. The present study aimed to determine the occurrence of genes conferring resistance to fluoroquinolone, determining of the prevalence of insertion sequence elements IS256, IS257 and different superantigens (SAgs) among CoNS isolates obtained from various clinical sources. Materials and methods The current study conducted on a total of the 91 CoNS species recovered from clinical specimens in Hamadan hospitals in western Iran in 2017–2019. The antimicrobial susceptibility testing was performed using disk diffusion method and the presence of the IS256 and IS257, genes conferring resistance to fluoroquinolone and enterotoxins/enterotoxin-like encoding genes were investigated by polymerase chain reaction (PCR) method. Results Among genes encoding classic enterotoxins, sec was the most frequent which was carried by 48.4% of the 91 isolates, followed by seb in 27.5% of the isolates. None of the CoNS isolates was found to be positive to enterotoxin-like encoding genes. In 11(12%) of all isolates that were phenotypically resistant to levofloxacin, 9 isolates (81.8%) were positive for gyrB, 8 isolates (72.7%) were positive for gyrA, 8 isolates (72.7%) harbored grlB and 7 isolates (63.6%) were found to carry grlA. The IS256 and IS257 were identified in 31.8% and 74.7% of the isolates, respectively. The results of statistical analysis showed a significant association between the occurrence of staphylococcal enterotoxins (SEs) encoding genes and antimicrobial resistance. Conclusion Antimicrobial resistant determinants and SEs are co-present in clinical CoNS isolates that confer selective advantage for colonization and survival in hospital settings. The coexistence of insertion elements and antibiotic resistance indicate their role in pathogenesis and infectious diseases.

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Prevalence and Distribution of Resistance and Enterotoxins/Enterotoxin-likes Genes in Different Clinical Isolates of Coagulase-negative Staphylococcus

10.21203/rs.2.22783/v2 ◽

2020 ◽

Author(s):

Mona Nasaj ◽

Zahra Saeidi ◽

Hamed Tahmasebi ◽

Sanaz Dehbashi ◽

Mohammad Arabestani

Keyword(s):

Selective Advantage ◽

Diffusion Method ◽

Coagulase Negative Staphylococcus ◽

Disk Diffusion Method ◽

Genes Encoding ◽

Sequence Elements ◽

Insertion Elements ◽

Pcr Method ◽

Polymerase Chain ◽

Encoding Genes

Abstract Background: Coagulase-negative staphylococcus (CoNS) are considered to be the major reservoirs for genes facilitating the evolution of S. aureus as a successful pathogen. The present study aimed to determine the occurrence of genes conferring resistance to fluoroquinolone, determining of the prevalence of insertion sequence elements IS256, IS257 and different superantigenes (SAgs) among CoNS isolates obtained from various clinical sources.Materials and Methods: The current study conducted on a total of the 91 CoNS species recovered from clinical specimens in Hamadan hospitals in western Iran in 2017-19. The antimicrobial susceptibility testing was performed using disk diffusion method and the presence of the IS256 and IS257, genes conferring resistance to fluoroquinolone and enterotoxins/enterotoxin-like encoding genes were investigated by Polymerase Chain Reaction (PCR) method. Results: Among genes encoding classic enterotoxins, sec was the most frequent which was carried by 48.4% of the 91 isolates, followed by seb in 27.5% of the isolates. None of the CoNS isolates was found to be positive to enterotoxin-like encoding genes. In 11(12%) of all isolates that were phenotypically resistant to levofloxacin, 9 isolates (81.8%) were positive for gyrB, 8 isolates (72.7%) were positive for gyrA, 8 isolates (72.7%) harbored grlB and 7 isolates (63.6%) were found to carry grlA. The IS256 and IS257 were identified in 31.8 % and 74.7% of the isolates, respectively. The results of statistical analysis showed a significant association between the occurrence of staphylococcal enterotoxins (SEs) encoding genes and antimicrobial resistance.Conclusion: Antimicrobial resistant determinants and SEs are co-present in clinical CoNS isolates that confer selective advantage for colonization and survival in hospital settings. The coexistence of insertion elements and antibiotic resistance indicate their role in pathogenesis and infectious diseases.

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Antibiotic resistance assessment of Acinetobacter baumannii isolates from Tehran hospitals due to the presence of efflux pumps encoding genes (adeA and adeS genes) by molecular method

BMC Research Notes ◽

10.1186/s13104-020-05387-6 ◽

2020 ◽

Vol 13 (1) ◽

Author(s):

Batool Basatian-Tashkan ◽

Mohammad Niakan ◽

Mansoor Khaledi ◽

Hamed Afkhami ◽

Fatemeh Sameni ◽

...

Keyword(s):

Acinetobacter Baumannii ◽

High Frequency ◽

Efflux Pumps ◽

Diffusion Method ◽

Toxic Substances ◽

Mechanisms Of Resistance ◽

Molecular Method ◽

Disk Diffusion Method ◽

Pcr Method ◽

Encoding Genes

Abstract Objective Acinetobacter baumannii (A. baumannii) has caused many problems in nosocomial infections. Efflux pumps are considered as one of the most important mechanisms of resistance in this bacterium and have the ability to excrete toxic substances such as antibiotics out of the cell. Results In this study, 60 isolates of A. baumannii were collected from patients in several hospitals in Tehran, Iran. After diagnosis using standard biochemical methods, the pattern of antibiotic susceptibility was determined using the disk diffusion method according to CLSI guidelines. The adeA and adeS genes were identified by PCR method. The highest resistance to Piperacillin and the lowest resistance to Gentamicin were observed (100% compared to 48.4%). 6.6% of the isolates had only adeA gene and adeS gene was observed in 8.4% of isolates and both genes were detected in 73.4% of the samples. Despite the high resistance of t A. baumannii o antibiotics and due to the high frequency of genes of adeA and adeS efflux pumps in A. baumannii isolates, it can be concluded that these efflux pumps may play an important role in resistance of this bacterium. By determining the pattern of antibiotic the resistance before treatment, the resistance of this pathogen can be prevented in societies.

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Prevalence of SHV-extended spectrum β-lactamase producing carbapenem –resistantKlebsiellapneumoniae among patients with lower respiratory tractinfections in Babylon Province-Iraq.

International Journal of Research in Pharmaceutical Sciences ◽

10.26452/ijrps.v9ispl1.1299 ◽

2018 ◽

Vol 9 (SPL1) ◽

Author(s):

Fatima Moeen Abbas

Keyword(s):

Resistance Rate ◽

Combination Method ◽

Diffusion Method ◽

Disk Diffusion Method ◽

Carbapenem Resistant ◽

Extended Spectrum ◽

Pcr Method ◽

Polymerase Chain ◽

Tract Infections ◽

Positive Results

This study was carried out to screen the prevalence of Klebsiella pneumoniae isolated from patients with lower respiratory tract infections in Babylon province.From December,2015 to the end of March,2016,a total of 100 sputum samples were collected from patients visited or hospitalized Merjan Teaching Hospital and Al- Hashimya General Hospital. Fifteenth (65%) isolates were identified as Klebsiellapneumoniae. All bacterial isolates were evaluated for extended spectrum β-lactamase (ESBL) production phenotypically using disk combination method. Eleven (73.3%) isolates were detected as ESBL-producers. Kirby-Bauer disk diffusion method was employed to determine resistance profile of ESBLs-positive isolates. Higher rates of resistance were observed for ampicillin and piperacillin antibiotics with (81.8%) and (72.7%) resistance rate, respectively, while the lowest rate was noticed for imipenem antibiotic (14.28%). Carbapenem-resistant isolates were investigated for blaSHV gene by Polymerase Chain Reaction (PCR) method, 2 (100%) isolates gave positive results.

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Prevalence, Antibiogram, and cdt Genes of Toxigenic Campylobacter jejuni in Salad Style Vegetables (Ulam) at Farms and Retail Outlets in Terengganu

Journal of Food Protection ◽

10.4315/0362-028x.jfp-14-109 ◽

2015 ◽

Vol 78 (1) ◽

pp. 65-71 ◽

Cited By ~ 7

Author(s):

MOHD IKHSAN KHALID ◽

JOHN YEW HUAT TANG ◽

NABILA HUDA BAHARUDDIN ◽

NASIHA SHAKINA RAHMAN ◽

NURUL FAIZZAH RAHIMI ◽

...

Keyword(s):

Antibiotic Resistance ◽

Multiplex Pcr ◽

Campylobacter Jejuni ◽

Antibiotic Susceptibility ◽

Penicillin G ◽

Diffusion Method ◽

Cytolethal Distending Toxin ◽

Disk Diffusion Method ◽

Retail Outlets ◽

Pcr Method

The present study was conducted to investigate the prevalence and antibiotic resistance among Campylobacter jejuni in ulam at farms and retail outlets located in Kuala Terengganu, Malaysia. A total of 526 samples (ulam, soil, and fertilizer) were investigated for the presence of C. jejuni and the gene for cytolethal distending toxin (cdt) by using a multiplex PCR method. Antibiotic susceptibility to 10 types of antibiotics was determined using the disk diffusion method for 33 C. jejuni isolates. The average prevalence of contaminated samples from farms, wet markets, and supermarkets was 35.29, 52.66, and 69.88%, respectively. The cdt gene was not detected in 24 of the 33 C. jejuni isolates, but 9 isolates harbored cdtC. Antibiotic resistance in C. jejuni isolates was highest to penicillin G (96.97% of isolates) followed by vancomycin (87.88%), ampicillin (75.76%), erythromycin (60.61%), tetracycline (9.09%), amikacin (6.06%), and norfloxacin (3.03%); none of the isolates were resistant to ciprofloxacin, enrofloxacin, and gentamicin. In this study, C. jejuni was present in ulam, and some isolates were highly resistant to some antibiotics but not to quinolones. Thus, appropriate attention and measures are required to prevent C. jejuni contamination on farms and at retail outlets.

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Molecular Detection and Antibiotyping of Multidrug-Resistant Salmonella Isolated from Houseflies in a Fish Market

Pathogens ◽

10.3390/pathogens8040191 ◽

2019 ◽

Vol 8 (4) ◽

pp. 191 ◽

Cited By ~ 5

Author(s):

Sobur ◽

Hasan ◽

Haque ◽

Mridul ◽

Noreddin ◽

...

Keyword(s):

Molecular Detection ◽

Multidrug Resistant ◽

Diffusion Method ◽

Resistant Bacteria ◽

Salmonella Spp ◽

Disk Diffusion Method ◽

Antibiotic Resistant ◽

Fish Market ◽

Pcr Method ◽

High Level

Houseflies (Musca domestica) are well-known mechanical vectors for spreading multidrug-resistant bacteria. Fish sold in open markets are exposed to houseflies. The present study investigated the prevalence and antibiotypes of multidrug-resistant (MDR) Salmonella spp. in houseflies captured from a fish market. Direct interviews with fish vendors and consumers were also performed to draw their perceptions about the role of flies in spreading antibiotic-resistant bacteria. A total of 60 houseflies were captured from a local fish market in Bangladesh. The presence of Salmonella spp. was confirmed using PCR method. Antibiogram was determined by the disk diffusion method, followed by the detection of tetA, tetB, and qnrA resistance genes by PCR. From the interview, it was found that most of the consumers and vendors were not aware of antibiotic resistance, but reported that flies can carry pathogens. Salmonella spp. were identified from the surface of 34 (56.7%) houseflies, of which 31 (91.2%) were found to be MDR. This study revealed 25 antibiotypes among the isolated Salmonella spp. All tested isolates were found to be resistant to tetracycline. tetA and tetB were detected in 100% and 47.1% of the isolates, respectively. Among the 10 isolates phenotypically found resistant to ciprofloxacin, six (60%) were found to be positive for qnrA gene. As far as we know, this is the first study from Bangladesh to report and describe the molecular detection of multidrug-resistant Salmonella spp. in houseflies in a fish market facility. The occurrence of a high level of MDR Salmonella in houseflies in the fish market is of great public health concerns.

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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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Phylogenetic Groups ofEscherichia coliStrains from Patients with Urinary Tract Infection in Iran Based on the New Clermont Phylotyping Method

BioMed Research International ◽

10.1155/2015/846219 ◽

2015 ◽

Vol 2015 ◽

pp. 1-7 ◽

Cited By ~ 22

Author(s):

Darioush Iranpour ◽

Mojtaba Hassanpour ◽

Hossein Ansari ◽

Saeed Tajbakhsh ◽

Gholamreza Khamisipour ◽

...

Keyword(s):

Antibiotic Resistance ◽

Cross Sectional Study ◽

Diffusion Method ◽

Resistance Pattern ◽

Multiple Drug ◽

Phylogenetic Groups ◽

Disk Diffusion Method ◽

Cross Sectional ◽

E Coli ◽

Pcr Method

Objectives.In 2013, Clermont classifiedE. colistrains into eight phylogenetic groups using a new quadruplex PCR method. The aims of this study were to identify the phylogenetic groups ofE. colibased on this method and to assess their antibiotic resistance patterns in Bushehr, Iran.Methods. In this cross-sectional study, 140E. coliisolates were subjected to phylogenetic typing by a quadruplex PCR method. Antimicrobial susceptibility testing was performed by disk diffusion method.Results. Phylogenetic group B2 was most predominant (39.3%), followed by unknown (27.1%), E (9.3%), C and clade I (each 6.4%), B1 (5%), F and D (each 2.9%), and A (0.7%). The most common antibiotic resistance was related to amoxicillin (82.1%) and the least to meropenem (0.7%). 82.14% of isolates were multiple drug resistant (MDR). Antibiotic resistance was mainly detected in group B2 (50%).Conclusions.Our findings showed the high prevalence of MDRE. coliisolates with dominance of group B2. About 25% ofE. coliisolates belong to the newly described phylogroups C, E, F, and clade I. Such studies need to be done also in other regions to provide greater understanding of the antibiotic resistance pattern and the prevalences of different phylogenetic groups.

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Characteristics of coagulase positive staphylococci isolated from milk in cases of subclinical mastitis

Acta veterinaria ◽

10.2478/acve-2014-0012 ◽

2014 ◽

Vol 64 (1) ◽

pp. 115-123 ◽

Cited By ~ 4

Author(s):

Nataša Rajić Savić ◽

Vera Katić ◽

Branko Velebit

Keyword(s):

Meca Gene ◽

Subclinical Mastitis ◽

Penicillin G ◽

Diffusion Method ◽

Disc Diffusion ◽

Disk Diffusion Method ◽

Phenotypic Resistance ◽

High Virulence ◽

Pcr Method ◽

Coagulase Positive Staphylococci

Abstract Coagulase-positive staphylococci are the most common pathogen causing subclinical mastitis in cows. Their main characteristic is a high virulence which leads to chronic infection. A total of 213 isolates of coagulase-positive staphylococci were tested. The majority of isolates (58%) formed a gold pigment, then light gold (28%), white gold (8%), golden gray, creamy white and white (2%). The majority of isolated coagulase-positive staphylococci produce beta hemolysis on esculin blood agar (50%), alpha and beta hemolysis (36%), beta and delta hemolysis (8%), delta hemolysis (4%), and alpha hemolysis (2%). Biochemical and molecular identification was performed by APISTAPH and multiplex PCR method. The majority of isolates were identified as S. aureus (88%), S. chromogenes (4%), and 2% of the isolates were identified as S. lentus, S. sciuri, S. xylosus, S. intermedius by APISTAPH. Antimicrobial susceptibility to penicillin G, was found by the Kirby Bauer disk diffusion method to be resistant (62.44%). For disc diffusion penicillin G sensitive isolates the minimal inhibitory concentration (MIC) was established for MIC50 and MIC90 as 0.003 mg/ml and 2μg/ml, respectively. For disc diffusion penicillin G resistant isolates MIC50 and MIC90 was 1.0μg/ml and 16μg/ ml, respectively. The study of phenotypic resistance to methicillin, as recommended by CLSI, established resistance to oxacillin in 5.26% of the isolates, while no resistance was found to cefoxitine. None of the tested isolates have the mecA gene.

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Molecular Characterization of Carbapenemase-Producing Escherichia coli and Salmonella in children with diarrhea in rural Burkina Faso.

10.21203/rs.3.rs-19069/v1 ◽

2020 ◽

Author(s):

Rene DEMBELE ◽

Ali Konaté ◽

Issiaka Soulama ◽

Wendpoulomdé A. D. Kaboré ◽

Assèta Kagambèga ◽

...

Keyword(s):

Escherichia Coli ◽

Burkina Faso ◽

Treatment Options ◽

Diffusion Method ◽

Bacterial Strains ◽

Disk Diffusion Method ◽

E Coli ◽

Klebsiella Pneumoniae Carbapenemase ◽

Encoding Genes

Abstract Background In recent years, Carbapenemase-producing Enterobacteriaceae (CPE) resistance to antibiotics has dramatically increased leading to limitations of their treatment options. In the present study, we investigated the occurrence of carbapenemase-producing Escherichia coli and Salmonella in rural Burkina Faso, using bacterial strains obtained from previous studies. Results Diarrheagenic Escherichia coli (DEC) strains was identified using 16-plex Polymerase Chain Reaction (PCR), whereas antibiotic susceptibility was realized using the disk diffusion method. Furthermore, multiplex PCR assays were used to characterize bla KPC, bla VIM and bla IMP genes in carbapenemase-producing E . coli and Salmonella . The study highlighted high resistance rates of the identified bacteria to common antibiotics. Likewise, two strains of E . coli were imipenem resistant with Carbapenemase-encoding genes. The genes detected were Klebsiella pneumoniae carbapenemase (KPC), Verona integrin-encoded metallo-β-lactamase (VIM) and Imipenemase (IMP-2) reaching a rate of 40% each. However, no Carbapenemase-encoding genes were detected in Salmonella isolates. Conclusions This study showed that for a real-time infection control and prompt application of antimicrobial chemotherapy, characterization of carbapenemase-producing Enterobacteriaceae in patients is crucial.

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