جستجوی مقالات مرتبط با کلیدواژه « بتالاکتامازهای وسیع الطیف » در نشریات گروه « پزشکی »

 There are several reports regarding the increase and growing prevalence of ESBLs producing organisms from different regions in the country. Considering that Klebsiella pneumoniae includes a significant percentage of hospital infections, therefore, knowing the pattern of resistance and sensitivity of this bacterium to beta-lactam antibiotics plays a significant role in the treatment and control of infections caused by this bacterium. As a result, the aim of the present study was to determine and evaluate the frequency of beta-lactamases The broad spectrum of Klebsiella pneumoniae urinary isolates was drug-resistant by genotypic and phenotypic methods.

In the present cross-sectional descriptive study conducted in 2018, 100 strains of Klebsiella pneumoniae were isolated from urine samples of patients with urinary tract infection from Al-Zahra Hospital, Isfahan. Klebsiella pneumoniae strains were identified and confirmed using standard biochemical tests. Antibiotic sensitivity pattern was investigated by disk diffusion method based on CLSI criteria. To perform the phenotypic verification test of broad-spectrum β-lactamase producing strains, the combined disc method was used based on CLSI criteria. PCR test was done with specific primers to identify blaSHV and bla TEM. The collected data were analyzed using one-way and independent one-way analysis of variance statistical tests.

Among 100 isolates related to urinary tract infection, 33 isolates indicated resistance to at least 4 antibiotics, the highest resistance to cefotaxime antibiotic (38%) and the least antibiotic resistance to cotrimaxazole (22%). The results of combined disk indicated that 10 isolates (86.8%) were broad-spectrum β-lactamase producers. Among them, 7 isolates (70%) had the SHV gene and the other 3 isolates did not have any of the TEM and SHV genes.

The results indicated a higher frequency of ESBLs and correspondingly a higher prevalence of antibiotic resistance in Klebsiella pneumoniae bacteria isolated from urinary tract infections.

Enterobacteriaceae produce the Extended-Spectrum Beta-Lactamases which is considered as an important resistant mechanism of beta-lactam antibiotics. The resistance to beta-lactam antibiotics is the main problem in the bacterial infections therapy. The prevalence of these enzymes changes in different geographical areas and with time. The present study aims to explore the frequency of the extended-spectrum blaSHV, blaCTX-M, blaTEM, in Enterobacter aerogenes isolated from urinary tract infections in Shahrekord City; the mentioned genes were investigated from the phenotypic and genotypic point of view.

In this cross-sectional descriptive study, antibacterial susceptibility patterns of 50 isolates of Enterobacter aerogenes to Cefotaxim, Ceftazidim, Cefterixon and cephalotin were tested using disk diffusion (Kirby-Buer) method. In addition, confirmatory tests for detecting ESBLs phenotypes were performed using Ceftazidim-clavulanic acid and Cefotaxim- clavulanic acid combination disks. Then, the presence of blaSHV, blaCTX-M, blaTEM, genes in the broad-spectrum beta-lactamase producing strains was assessed in the presence of specific primers.

Out of 50 isolates of Enterobacter aerogenesis investigated in this study, 32 isolates (64%) were identified to produce broad-spectrum β-lactamases in the phenotypic study of ESBLS, and the prevalence of blaCTX-M, blaTEM and blaSHV was reported as 30%, 20% and 14%, respectively. In the statistical analysis, a statistically significant correlation was observed between resistance to the antibiotic ceftriaxone and the blaCTX-M, gene (p<0.05).

The present study suggests that ESBL producing Enterobacter aerogenes isolates have a high prevalence. The increase in the number of these species is often caused due to the irrational prescription of antibiotics, which requires the use of new antimicrobial agents and limiting the unnecessary use of antimicrobial agents and increasing the use of infection control tools.

Acinetobacter baumannii has emerged as an opportunistic nosocomial pathogen that causes ventilator-associated pneumonia, bacteraemia, endocarditis, wound infections, meningitis and urinary tract infections in patients with serious underlying disease and immunocompromised patients, and in those undergoing prolonged hospitalization and surgical procedures involving long-term antimicrobial therapy. The majority of nosocomial A. baumannii isolates are resistant to different classes of antibiotic including cephalosporin's, penicillin's, carbapenem's, fluoroquinolones and aminoglycosides. Multidrug-resistant (MDR) A. baumannii isolates are a serious problem in healthcare settings worldwide, especially in Europe, Asia, Latin America and other areas. The majority of MDR strains have been isolated from adults attending intensive healthcare units and are associated with increased patient mortality and persistence of isolates in the hospital environment. Horizontal transfer of antibiotic resistance genes is thought to play a major role in the emergence and development of MDR strains. Treatment of infections caused by highly resistant isolates, especially MDR, XDR (extensively drug resistant) and PDR (pan drug resistant), can be difficult. Currently, beta-lactams are used as a selective drug in the treatment of multi-drug resistant Acinetobacter spp., although resistance to these agents is increasing. Metalo-beta-lactamases have different types that are often plasmid and among them blaVIM and blaNDM are the most prominent. The aim of this study was to evaluate the drug resistance and the frequency of blaVIM and blaNDM genes in isolated isolates from Isfahan and Shahrekord cities by molecular methods.

This cross-sectional study was performed on 500 clinical specimens including blood, ulcer, urine and respiratory tract collected from 3 hospitals in Isfahan (Alzahra and Kashani) and Shahrekord (Kashani) during one year from April 2018 to April 2019. After assembling samples, biochemical methods of Acinetobacter spp were identified. Susceptibility of isolates to the following antibiotics was examined using the disk diffusion method according to the Clinical and Laboratory Standards Institute guidelines. Multidrug resistance (MDR) was defined as resistance to at least one agent in three or more antimicrobial categories. The antimicrobial susceptibility test of the isolated organisms was completed by the disc diffusion method using the Kirby–Bauer technique. According to the recommendation of CLSI, all tests were performed on Mueller Hinton agar. The surface was lightly and uniformly inoculated by a cotton swab. Prior to inoculation, the swab stick was dipped into a bacterial suspension having visually equivalent turbidity to 0.5 McFarland standards. The swab stick was then taken out and squeezed on the wall of the test tube to discard extra suspension. Inoculated plates were incubated at 35°C for 24 h. On the next day, plates were read by taking measurements of zone of inhibition. Finally, DNA extraction from overnight cultures of A. baumannii isolates was performed according to the protocol provided with the QIAGEN DNA Mini kit (QIAGEN Inc., Valencia, CA). PCR primers were used to determine the frequency of blaVIM and blaNDM genes. The data were analyzed with SPSS version 17.0 software (SPSS, Inc., Chicago, IL). A chi-square test was used to determine the statistical significance of the data. A p<0.05 was considered significant.

Antibiotic resistance in 100 isolates of A. baumannii was related to antibiotics: Cefimoimide (97%), Ceftriaxone (95%), Amikacin (95%), Imipenem (76%), Piperacillin-tazobactam (70%), Meropenem (69%), Gentamicin (63%), Tobramycin (56%), Tetracycline (51%), and Ampicillin-Sulbactam (49%) and lowest resistance to Poly-Mixin B were obtained. The PCR results showed 17 and 20%, of strains carrying blaVIM and blaNDM genes, respectively. The prevalence rate of blaNDM in this study was 20%, which is contrary to studies conducted by Tognim et al. In 2011 (55%) which show that the prevalence rate of blaNDM has been decreasing over time. This decrease can be seen in the prevalence of blaVIM.

Increase in the incidence of A. baumannii in hospital points to the need to design protective programs such as controlling infections in the intensive care unit. Also, using molecular methods, these bacteria can be identified and their antibiotic resistance characteristics are determined and appropriate antibiotics are prescribed.

Due to the increase in urinary tract infection (UTI) caused by Extended- Spectrum β-lactamases (ESBLs) producing Escheria.coli strains and their resistance to conventional antibiotics, the development of new effective antimicrobial agents particularly nanoparticle based biological compounds is urgently required. The aim of this study was to evaluate the antibacterial effect of a new derivative of spirooxindole nanoparticles against ESBLs producing E. coli isolates obtained from patients with UTI.

This descriptive-observational study was performed on 60 E. coli isolates from Karaj city hospitals. Isolates were identified by standard biochemical tests. Antimicrobial susceptibility of isolates against Cefepime, Cefotaxime, Ceftazidime, Ceftriaxone, was determined using the Disk Diffusion Method. The new derivative of spiroxindole nanoparticles was prepared by electrosynthesis and examined with a scanning electron microscopy (SEM). ESBLs producing isolates were detected by the Combined Disk test. The broth microdilution method was performed to determine the Minimum inhibitory concentration (MIC) of nanoparticles

Antibiotic resistance of 60 Escherichia coli isolates was as follows: Cefepime 23.33%, Ceftazidime 16.66%, Cetfriaxone 30% and Cefotaxime 31.66%. 14 ESBLs producing Escherchia coli isolates were identified by a phenotypic confirmatory test. The MIC value of the understudied spirooxindole nanoparticles was obtained to be 50μg/ml.

Undertaking further studies, the understudied spirooxindole nanoparticle can be introduced as a new antibacterial compound.

Resistance to β-lactam antibiotics in the clinical isolates, in most cases is caused by βlactamase enzymes. In recent years, The incidence of broad-spectrum β-lactamase enzymes (ESBLs) among clinical isolates especially E.coli is greatly increased, since the β-lactamase have several subfamilies, using universal primers designed to detect the following complete families could be useful. β-lactamase producing enzymes (ESBLs) of E. coli has created many problems for patients. β-lactamase CTX-M-1 gene is the cause of resistance. The aim of this study was to evaluate CTX-M-1gene in E.coli.

In this practical study, susceptibility of isolated bacteria to 13 antibiotics were indicated by disk diffusion method according to CLSI guidelines and strains were analyzed for the presence of widespread βlactamase enzymes via two-disc synergy method. Thus، the prevalence of CTX-M1 ESBL gene samples were determined using PCR and the data were analyzed using ANOVA.

A total of 200 isolates of E.coli were isolated. The presence of CTX-M-1 gene were also isolated using the PCR method. From 200 strains studied, 62 (31%), of strains produced ESBL. After PCR processing of 62 produced ESBL, 43 isolates (69.4%) were identified as CTX-M-1 genes. Also, antibiotic susceptibility test showed the highest percentage of resistance to Cotrimoxazole antibiotic (50%) and the lowest antibiotic resistance to imipenem (0%).

The results of this study showed the high percentage of β-lactamase resistance among of E.coli strains. This is a serious public hazard that should be pointed out to measures for preventing this hazard. Considering the sensitivity of the studied beta-lactam resistant isolates and isolates in Iran to imipenem, a carbapenem with a non-beta-lactam antibiotic is recommended for the treatment of nosocomial infections caused by these strains

Emerging resistance to beta-lactam antibiotics among gram negative bacteria limits their usage. This study was done to determine the frequency of ESBLs producers and presence of CTX-M3 family gene (including CTX-M 3, 15, 22 subfamily) in Escherichia coli and Klebsiella pneumoniae isolated from different clinical specimens in Sina Hospital, Tabriz

71 isolates of E. coli and 63 K. pneumoniae were isolated from different clinical specimens sent to Division of Microbiology, Sina Hospital, Tabriz, Iran. Bacteria were identified by conventional phenotypic methods. ESBL production in E. coli and K. pneumoniae was first detected with combined disc method using Mueller-Hinton agar and later presence of CTX-M3 family gene was detected by PCR technique.

In this study, 41 (57.74%) E.coli and 45 (71.42%) K. pneumoniae isolates were observed as ESBL producers. Among them, 30 (73.17%) E. coli and 26 (57.77%) K.pneumoniae were found carrying CTX-M3 gene. Among various antibiotics used for ESBL detection, highest resistance towards cefpodoxime (92%) was observed in E.coli, while in K.pneumoniae 90% isolates show resistance towards cefpodoxime and azterornam.

Our study revealed that there is a high frequency of ESBLs producing isolates of E. coli and K. pneumoniae in our hospital set up. The problem elucidates the importance of designing more controlled surveillance of antibiotic resistance and need for large-scale epidemiologic studies to identify outcomes of the ESBL-production in gram negative bacilli.