Spread Of ESBL Genes Research Articles

Drug susceptibility and molecular epidemiology of Escherichia coli in bloodstream infections in Shanxi, China.

ObjectivesWe carried out a retrospective study to investigate the drug susceptibility and genetic relationship of clinical Escherichia coli isolates from patients with BSIs in Shanxi, China.MethodsE. coli isolates causing BSIs were consecutively collected from June 2019 to March 2020. Antimicrobial susceptibility testing was performed by broth microdilution method. PCR was used to detect antimicrobial resistance genes coding for extended-spectrum β-lactamases (ESBLs), phylogenetic groups and seven housekeeping genes of E. coli.ResultsA total of 76 E. coli were collected. Antimicrobial susceptibility testing revealed that the top six E. coli resistant antibiotics were ampicillin (90.7%), ciprofloxacin (69.7%), cefazolin (65.7%), levofloxacin (63.1%), ceftriaxone and cefotaxime (56.5%). Among the 76 isolates, 43 produced ESBLs. Molecular analysis showed that CTX-M-14 was the most common ESBLs, followed by CTX-M-15 and CTX-M-55. Phylogenetic group D (42.2%) predominated, followed by group B2 (34.2%), group A (18.4%) and group B1 (5.2%). The most prevalent sequence types (STs) were ST131 (15/76), ST69 (12/76) and ST38 (6/76).ConclusionsThis study is the first to report the phenotypic and molecular characteristics of E. coli isolated from BSIs in Shanxi, China. Our results indicated a high prevalence of MDR in E. coli strains isolated from BSIs and a serious spread of ESBL genes in Shanxi, especially the epidemiological blaCTX-M. Phylogenetic analysis indicated genetic diversity among E. coli BSIs isolates.

Study on Dispersal of Escherichia coli and Salmonella enterica in Retail Beef and Chicken Meat

This study was performed to detect the dispersal of Escherichia coli and Salmonella enterica as well as reveal its antibiogram and spread of ESBL genes in the isolates from retail beef and chicken meat. Eighty-two beef and chicken meat samples have been picked up from butcher's stores and restaurants in Cairo and Giza, Egypt. Escherichia coli were isolated from 15% of examined beef and chicken meat samples, which was 52%, 41%, 12% and 1% from raw beef, raw chicken beef ready for consumption and chicken ready for consumption samples respectively. However, Salmonella enterica was detected from 1% from chicken meat samples ready for consumption only which constitute 5% from different meat samples. Escherichia coli isolates were insensitive to Clindamycin and Rifampin 100% each and showed high resistance to Ciprofloxacin, 78.9%. While Salmonella enterica isolate was unsusceptible to Ceftazidime, Cefepime, Cefotaxime, Clindamycin, Ciprofloxacin and Rifampin. All Escherichia coli isolates as well as, salmonella enterica isolate were phenotypically ESBL positive. All of Escherichia coli isolates contained blaTEM gene while blaSHV gene was detected in 85% and 60% in members of Escherichia coli recovered from raw and ready for consumption meat respectively. blaTEM and blaSHV both genes were detected in Salmonella enterica isolate. While BlaCTX gene did not detect in any of the Escherichia coli and salmonella enterica isolates.

Types and prevalence of extended-spectrum beta-lactamase producing Enterobacteriaceae in poultry.

For several billion years, bacteria have developed mechanisms to resist antibacterial substances. In modern time, antibiotics are frequently used in veterinary and human medicine for prevention and treatment of diseases, globally still also for their growth promoting effects as feed additives. This complex situation has evolved in accelerating development and prevalence of multi-drug resistant bacteria in livestock and people. Extended-spectrum beta-lactamase (ESBL) producing bacteria are resistant to a wide range of ß-lactam antibiotics. They are currently considered as one of the main threats for the treatment of infections in humans and animals. In livestock and animal products, poultry and poultry products show the highest prevalence of ESBL-producers with CTX-M-1, TEM-52 and SHV-12 being the most common ESBL-types in poultry. Escherichia coli and Salmonella spp. are the bacteria in poultry, which carry ESBL-genes most frequently. ESBL-producing bacteria are present at every level of the poultry production pyramid and can be detected even in the meconium of newly hatched chicks. The environment close to poultry barns shows high prevalence rates of these bacteria and contributes to an ongoing infection pressure with further ESBL-types. Probiotics have been shown to successfully reduce ESBL-producers in chicken, as well as ESBL-gene transfer. Other feed additives, such as zinc and copper, increase the prevalence of ESBL-producing bacteria when fed to animals. To our best knowledge, this is the first publication presenting a comparative overview of the prevalence of ESBL-types using data from different countries. To reduce the hazard for public health from poultry carrying high numbers of ESBL-producers, preventive measurements must include the surrounding environment and avoidance of antibiotic usage at all levels of the production pyramid. The first results, of the research on the impact of feed additives on the spread of ESBL-genes, indicate the diet as a further, possible magnitude of influence.

Characterization of Extended-Spectrum β-Lactamase-Carrying Plasmids in Clinical Isolates ofKlebsiella pneumoniaefrom Taiwan

We analyzed the replicon types, sizes, and restriction fragment length polymorphism (RFLP) typing of plasmids carrying extended-spectrum β-lactamase (ESBL) genes in Klebsiella pneumoniae isolates from Taiwan. Fifty-one Escherichia coli transconjugant strains with plasmids from ESBL-producing K. pneumoniae from the Taiwan Surveillance of Antimicrobial Resistance III Program in 2002 were included. All the 51 plasmids carried a blaCTX-M gene, the majority of which were blaCTX-M-3 (28/51 [54.9%]). Plasmids ranged in size from 126 to 241 kb by S1 nuclease digestion and subsequent pulsed-field gel electrophoresis, and the most common plasmid size (37.3%) was 161-170 kb. The most common replicon type of plasmids was incompatibility group (Inc)A/C (60.8%). The IncA/C plasmids all carried blaCTX-M (blaCTX-M-3, -14, -15), and some also carried blaSHV (blaSHV-5, -12) genes. All 51 plasmids could be typed with PstI, and 27 (52.9%) belonged to 10 clusters. Thirty-eight of the 51 plasmids were typable with BamHI, and 21 plasmids (55.3%) fell into 7 clusters. Plasmids in the same cluster belonged to the same incompatibility group, with the exception of cluster C6. In conclusion, IncA/C plasmids are the main plasmid type responsible for the dissemination of ESBL genes of K. pneumoniae from Taiwan. RFLP with PstI possessed better discriminatory power than that with BamHI and PCR-based replicon typing for ESBL-carrying plasmids in K. pneumoniae in this study. Greater than 50% of plasmids fell into clusters, and >60% of cluster-classified plasmids were present in clonally unrelated isolates, indicating that horizontal transfer of plasmids plays an important role in the spread of ESBL genes.