Changes in antimicrobial resistance patterns of ocular surface bacteria isolated from horses in the UK: An eight‐year surveillance study (2012‐2019)

2020 ◽  
Vol 23 (6) ◽  
pp. 950-956
Author(s):  
Ria H. Chalder ◽  
Tim Knott ◽  
James O. Rushton ◽  
Danica Nikolic‐Pollard
Keyword(s):  
Antimicrobial Resistance ◽  
Ocular Surface ◽  
Surveillance Study ◽  
Resistance Patterns ◽  
The Uk

scholarly journals Regional Dissemination of a Carbapenemase-encoding Plasmid: Plasmidome analysis Reveals Diverse Adaptations of Carbapenemase-Producing Enterobacteriaceae

2020 ◽  
Author(s):  
Ryuichiro Abe ◽  
Yukihiro Akeda ◽  
Yo Sugawara ◽  
Dan Takeuchi ◽  
Yuki Matsumoto ◽  
...  
Keyword(s):  
Antimicrobial Resistance ◽  
Bacterial Infections ◽  
Single Point ◽  
Complete Sequence ◽  
Surveillance Study ◽  
Single Point Mutation ◽  
Chromosomal Integration ◽  
Carbapenemase Gene ◽  
Resistance Patterns ◽  
Horizontal Spread

Abstract Background. The global dissemination of carbapenem-resistant Enterobacteriaceae (CRE) threatens human health by limiting the range of usable antibiotics even against common bacterial infections. The spread of CRE is primarily due to the transmission of carbapenemase genes located on plasmids. However, few studies have comprehensively identified regionally spreading carbapenemase-encoding plasmids because of the difficulty to determine the complete sequence of a plasmid encoding carbapenemases. In a CRE surveillance study of 1,507 patients from 43 hospitals in northern Osaka, Japan, we previously found that 12% of the patients carried CRE and 95% of CRE isolates were IMP-6 producers. This result suggested a vast horizontal spread of a clonal plasmid carrying blaIMP-6 among Enterobacteriaceae in this region. In the current study, we aimed to describe the dynamics of this regional horizontal plasmid transmission.Results. We systematically analysed the plasmids of 230 CRE isolates carrying blaIMP obtained in our previous surveillance study by using whole genome sequencing and Southern blotting. We detected a major population (187 out of 230 blaIMP-positive CRE isolates, 85.6%) that carried blaIMP-6 on the IncN plasmid pKPI-6, along with diverse minor subpopulations. Among the subpopulations, we identified a novel cluster carrying an IncF plasmid that leads to heteroresistance due to amplification of blaIMP-6, resulting in covert transmission of blaIMP-6 or occasional chromosomal integration of blaIMP-6. In addition, we detected one isolate that harboured blaIMP-1, which is identical to blaIMP-6 except for a single point mutation, on pKPI-6 and thus had acquired a broader range of antimicrobial resistance. Conclusions. Carbapenemase-encoding plasmid tracking revealed the clonal dissemination of pKPI-6 among chromosomally distinct isolates. Focusing on the mode of carbapenemase gene carriage is helpful for monitoring of horizontal spread of CRE isolates that is difficult to trace only by the comparisons of the whole genomes. A seemingly clonal horizontal dissemination of the predominant plasmid had embraced heterogenous subpopulations that contribute to diverse adaptations including covert transmission, stable chromosomal integration of blaIMP-6, or broadened antimicrobial resistance patterns, ultimately leading to treatment failure.

The Causative Organisms of Bacterial Meningitis and their Antimicrobial Resistance Profiles in Iranian Children in 2011-2016

2020 ◽  
Vol 20 (2) ◽  
pp. 229-236
Author(s):  
Sepideh Keshavarz Valian ◽  
Shima Mahmoudi ◽  
Babak Pourakbari ◽  
Maryam Banar ◽  
Mohammad Taghi Haghi Ashtiani ◽  
...  
Keyword(s):  
Antimicrobial Resistance ◽  
Bacterial Meningitis ◽  
Medical Center ◽  
Blood Cultures ◽  
Gram Positive ◽  
Gram Negative ◽  
Number Of Patients ◽  
Resistance Patterns ◽  
Iranian Children ◽  
Surgery Department

Objective: The study aimed to describe the identity and antimicrobial resistance patterns of the causative agents of bacterial meningitis in children referred to Children’s Medical Center (CMC) Hospital, Tehran, Iran. Methods: This retrospective study was performed at CMC Hospital during a six-year period from 2011 to 2016. The microbiological information of the patients with a diagnosis of bacterial meningitis was collected and the following data were obtained: patients’ age, sex, hospital ward, the results of CSF and blood cultures, and antibiotic susceptibility profiles of isolated organisms. Results: A total of 118 patients with bacterial meningitis were admitted to CMC hospital. Sixty-two percent (n=73) of the patients were male. The median age of the patients was ten months (interquartile range [IQR]: 2 months-2 years) and the majority of them (n=92, 80%) were younger than two years of age. The highest number of patients (n=47, 40%) were admitted to the surgery department. Streptococcus epidermidis was the most frequent isolated bacterium (n=27/127, 21%), followed by Klebsiella pneumoniae (n=20/127, 16%), and Staphylococcus aureus (n=16/127, 12.5%). Blood culture was positive in 28% (n=33/118) of patients. Ampicillin-sulbactam and imipenem were the most effective antibiotics against Gram-negative bacteria isolated from CSF cultures. In the case of Gram-positive organisms, ampicillinsulbactam, vancomycin, and linezolid were the best choices. Imipenem was the most active drug against Gram-negative blood pathogens. Also, ampicillin and vancomycin had the best effect on Gram-positive bacteria isolated from blood cultures. Conclusion: Results of this study provide valuable information about the antibiotic resistance profiles of the etiologic agents of childhood meningitis, which can be used for prescription of more effective empirical therapies.

Antimicrobial Resistance and Presence of Class 1 Integrons Among Different Serotypes of Salmonella spp. Recovered From Children with Diarrhea in Tehran, Iran

2020 ◽  
Vol 20 (2) ◽  
pp. 160-166
Author(s):  
Seyedeh Hanieh Eshaghi Zadeh ◽  
Hossein Fahimi ◽  
Fatemeh Fardsanei ◽  
Mohammad Mehdi Soltan Dallal
Keyword(s):  
Antibiotic Resistance ◽  
Antimicrobial Resistance ◽  
Multidrug Resistant ◽  
Salmonella Spp ◽  
Class 1 Integron ◽  
Class 1 Integrons ◽  
Food Borne ◽  
Class 1 ◽  
Resistance Patterns ◽  
C 30

Background: Salmonellosis is a major food-borne disease worldwide. The increasing prevalence of antimicrobial resistance among food-borne pathogens such as Salmonella spp. is concerning. Objective: The main objective of this study is to identify class 1 integron genes and to determine antibiotic resistance patterns among Salmonella isolates from children with diarrhea. Methods: A total of 30 Salmonella isolates were recovered from children with diarrhea. The isolates were characterized for antimicrobial susceptibility and screened for the presence of class 1 integron genes (i.e. intI1, sulI1, and qacEΔ1). Results: The most prevalent serotype was Enteritidis 36.7%, followed by Paratyphi C (30%), and Typhimurium (16.7%). The highest rates of antibiotic resistance were obtained for nalidixic acid (53.3%), followed by streptomycin (40%), and tetracycline (36.7%). Regarding class 1 integrons, 36.7%, 26.7%, and 33.3% of the isolates carried intI1, SulI, and qacEΔ1, respectively, most of which (81.8%) were multidrug-resistant (MDR). Statistical analysis revealed that the presence of class 1 integron was significantly associated with resistance to streptomycin and tetracycline (p = 0.042). However, there was no association between class 1 integron and other antibiotics used in this study (p > 0.05). Conclusion: The high frequency of integron class 1 gene in MDR Salmonella strains indicates that these mobile genetic elements are versatile among different Salmonella serotypes, and associated with reduced susceptibility to many antimicrobials.

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