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Showing 5 results for Escherichia Coli
Molecular detection of TEM and AmpC (Dha, mox) broad spectrum β-lactamase in clinical isolates of Escherichia coli
Soltan Dallal Mm, Molla Aghamirzaei H, Fallah Mehrabadi J, Rastegar Lari A, Sabbaghi A, Eshraghian Mr, Fard Sanei A, Bakhtiari R, Hanafi Abdar M,
Volume 68, Issue 6 (9-2010)
Abstract

Background: Beta- lactamase enzymes are the most important resistant factors to beta lactam antibiotics among gram negative bacteria. Nowadays, the prevalence of beta- lactamase infection is increasing worldwide and drawn the scientists attention as an important subject. Due to high prevalence of bacteria contained TEM beta lactamase and AmpC enzymes, using molecular methods especially designing universal primers could be valuable to detect all of them. The aim of this study was to determine the prevalence of TEM and AmpC (Dha and MOX) beta- lactamase genes using universal primers.

Methods: A total of 500 clinical specimens from various Hospitals in Tehran, Iran were collected and analyzed for E. coli based on biochemical tests. These clinical specimens were also screened by Disk diffusion agar, combined disk method and PCR to detect the samples producing extended- spectrum beta- lactamase.

Results: Overall 200 isolates of Escherichia coli were collected from the 500 clinical specimens out of which 128(64%) isolates were positive by PCR assay and showed bla- TEM, bla- AmpC (Dha, MOX) genes, 74(57.8%) and 5(3.9%) to have bla- TEM and bla Dha, respectively. Mox gene was not detected in any of the specimens.

Conclusions: Our results revealed that using the molecular methods with phenotype methods is very essential for complete detection of Beta- lactamases. There is the need for updating the treatment protocol because the prevalence of this resistance is increasing.


The prevalence of extended-spectrum beta-lactamases and CTX-M-1 producing Escherichia coli in urine samples collected at Tabriz city Hospitals
Soltan Dallal Mm, Azarsa M, Shirazi Mh, Rastegar Lari A, Owlia P, Fallah Mehrabadi J, Sabbaghi A, Molla Aghamirzaei H, Shamkani F, Avadis Yans S, Mobasseri G, Bakhtiari R, Sharifi Yazdi Mk,
Volume 69, Issue 5 (8-2011)
Abstract

Background: Numerous use of Beta Lactame in treatment of bacterial infections resulted in increments of drug resistance of such bacteria. One of difficulties in treatment of hospital infections is Extended Spectrum Beta Lactamase (ESBL) among isolated clinical strains of E.coli. Since some of ESBL strains shows double reaction in drug sensitivity test at in vitro and in vivo condition, therefore it makes difficulties in selection of right treatment. In the last years, CTX-M enzymes have become the most prevalent ESBLs in worldwide. The prevalence of ESBL types largely remains unknown in many parts of the Iran. This study was made to find the prevalence of ESBL-producing E.coli and molecular detection of CTX-M-1 in Tabriz.

Methods: In the present study, 400 urine samples collected between November 2009 and April 2010, from Tabriz Hospitals were studied. Out of the 400 samples, 188 E.coli isolates were detected by standard biochemical tests. Susceptibility to antimicrobial agents was tested to 10 antibiotics by the disk agar diffusion (DAD) method. ESBL production was screened by phenotypic test that included both separate and combined disk agar diffusion techniques. The screened isolates were investigated by PCR assay to detect CTX-M-1 gene.

Results: From the total 188 E.coli isolates, 82 (43.6%) were shown to produce ESBLs by phenotypic test. During the PCR method on the 82 isolates, 69 (84.1%) were confirmed as CTX-M-1 producing group.

Conclusion: The present study showed that CTX-M-producing isolates were increasing among E.coli strains and indicated the need for adequate susceptibility tests in laboratories for choosing the appropriate antibiotics for treatment.


Removal of E. coli and S. aureus from polluted water using electrolysis method with Al-Fe electrodes
Mitra Gholami , Shahram Nazari, Ahmad Reza Yari , Seyed Mohsen Mohseni , Soudabeh Alizadeh Matboo ,
Volume 75, Issue 2 (5-2017)
Abstract

Background: Electrolysis is an electrochemical method for the treatment of water. recently water disinfection by electrochemical methods has been increasingly carried out. The aim of this applied research was to investigate the removal of Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) bacteria from drinking water by using electrolysis method with Al-Fe electrodes parallel with the monopole mode.

Methods: An experimental study was conducted in the laboratory of microbiology, Iran University of Medical Science in May 2017. In this study, the contaminated water samples were prepared through adding 103, 104 and 105 E. coli and S. aureus bacteria per 1 milliliters (mL) of drinking water. Independent variables Included: different concentrations of E.coli and S. aureus bacteria (103, 104 and 105 CFU/ml), reaction time (5, 10, 15, 20 and 25 min), initial pH (7, 8 and 9), electrode gap (1, 2 and 3 cm), current density (0.83, 1.67 and 3.3 mA/cm2) to determine the optimum conditions were investigated. One-way ANOVA was used to analyze the results.

Results: The results show that in the optimum conditions with increasing the pH from 7 to 9 removal efficiency of bacterial strains of E. coli and S. aureus were decreased significantly from 98 to 73% and 99.1 to 76%, respectively. In initial concentration of 104 CFU/ml, optimum conditions were obtained for current density, reaction time and electrodes gap, 1.67 mA/cm2, 20 min and 2 cm, respectively. With increasing current density and reaction time in both strains of bacteria, were decreased significantly. The electrodes gap do not have much impact on the efficiency of the process. The amount of electrical energy consumed in optimal conditions was calculated 0.5128 kilowatt-hour (kWh/h). Statistical analysis shows that exist significant relationship (P<0.01) between initial concentrations of bacterial strains and efficiency of the process.

Conclusion: According to the results, E. coli and S. aureus, removal efficiency were obtained more than 98%, therefore electrolysis process can be used in the removal of pathogenic bacteria from drinking water.

Molecular typing of fluoroquinolone resistant Escherichia coli isolates from patients undergoing prostate biopsy
Amir Hasanzadeh , Mohammad Reza Pourmand , Shahram Gooran , Hasan Hosainzadegan , Asghar Tanomand , Gholamreza Pourmand ,
Volume 76, Issue 9 (12-2018)
Abstract
Background: Escherichia coli (E. coli) is one of the most important infectious agents in patients undergoing prostate biopsy. It belongs to a large family of gram-negative rods, Enterobacteriaceae. This family includes members of the normal flora of the intestine that are only occasionally pathogenic. Recent considerations of rectal colonization with fluoroquinolone-resistant E. coli shows the need to change strategy of treatment of infection in patients undergoing prostate biopsy. Therefore, the purpose of this study was to determine molecular typing of fluoroquinolone resistant (FQR) E. coli rectal isolates and associated infections in patients undergoing prostate biopsy.
Methods: In this prospective cohort study, rectal swabs were collected from 158 male patients before prostate biopsy at the Urology Research Center of Sina Hospital, Tehran, Iran, from March 2015 to February 2016. The FQR organisms were isolated using selective media, and antibiotic susceptibility pattern was determined for following antibiotics, ampicillin, levofloxacin, cotrimoxazole, amoxicillin-clavulanate, cefazolin, ceftazidime, cefepime, gentamicin, piperacillin-tazobactam, nitrofurantoin, amikacin, fosfomycin, imipenem. In general, phylogenetic background, prevalence of E. coli sequence type 131 (ST131) and its subclones (H30 and H30-Rx ST131) were compared in two groups of FQR E. coli rectal colonization and clinical isolates.
Results: In total, 73 patients had a positive rectal culture for FQR gram-negative bacteria, the most prevalent isolate of which was E. coli. Phylogenetic group B2 was most predominant, followed by A, E, C and D, B1 and F. The antibiotic susceptibility patterns for the FQR organisms showed high levels of resistance to ampicillin and trimethoprim-sulfamethoxazole, while the resistance to amikacin, fosfomycin and imipenem remained very low. In general, antibiotic resistance to several antibiotic was mainly detected in group B2 and with ST131 genotype. Despite the increase in infections among patients colonized with strains of E. coli ST131, its frequency was almost statistically significant between colonized and infected groups.
Conclusion: The ST131 pathogen has a high prevalence in rectal colonization and post prostate biopsy infections, which showed widespread resistance to common antibiotics.

Comparison of antibiogram test results of patients suspected of urinary tract infection with two methods, fast and classic
Hamid Reza Ghasemi Basir , Fariba Keramat, Abbas Moradi, Yeganeh Ghasemi, Ali Saadatmand,
Volume 79, Issue 12 (3-2022)
Abstract
Background: Urinary tract infections are among the most common diseases in different communities and occur in all age groups. Failure to diagnose the disease correctly and promptly can cause complications such as damage to the urinary tract and kidney parenchyma, increased blood pressure, uremia. Also, in pregnant female patients It may lead to premature birth and even abortion. Therefore, correct and timely administration of antibiotics is very important in the treatment of patients. This study aimed to compare the results of antibiogram testing of patients with suspected urinary tract infections by both rapid and classical methods.
Methods: This cross-sectional study was performed from the beginning of March to the beginning of September 2019, on patients with urinary tract infection Who had been referred to Sina Hospital of Hamedan, Iran. Urine samples were collected 20 cc from patients. The test was performed directly at the same time with urine culture to determine antibiotic susceptibility. The agreement between the two methods was considered as a huge error, major error and minor error. Finally, the data were statistically analyzed with SPSS software version 16.
Results: 92 patients, 23 men (25%) and 69 women (75%) with a mean age of 53.18±18.49 years were included in the study. Direct testing had a significant agreement with the standard test in 90.8% of the results (P<0.001). 9.2% of the antibiogram tests did not match, of which 0.3% were huge errors, 4.7% were major errors and 4.2% were minor errors. The highest number of microorganisms found were Escherichia coli (n=66), Klebsiella pneumoniae (n=13), Pseudomonas aeruginosa (n=6), Acinetobacter (n=1), Enterococcus (n=2), Alcaligenes (n=1), Streptococcus (n=1), Staphylococcus haemolyticus (n=1) and Moraxella (n=1) respectively. The highest rates of urinary tract infections were with Escherichia coli, third-generation cephalosporin antibiotics, and broad-spectrum antibiotics.
Conclusion: The agreement between the direct and standard antibiogram method was acceptable, and the direct antibiogram method can be cited by doctors in many cases.
 

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