ABSTRACT
One of the most common infections in human is urinary tract infection [UTI] and Uropathogenic Escherichia coli is one of its major causative agents. UTI is extremely common among young women. Children under age 5 are also highly at risk. Considering the prevalence of this disease, it is necessary to design an appropriate diagnostic method for its effective diagnosis. The aim of present study was to identify the prevalence of two virulence genes [sat and vat] among Uropathogenic E. coli isolates. Urine samples were taken from 350 patients with urinary tract infection. The samples were cultured on EMB agar and Blood agar. The suspected E. coli colonies were isolated and confirmed by biochemical tests. The genomic DNA was extracted from 297 isolated E. coli and target genes were amplified by PCR. The amplicons were sequenced and analyzed with ClustalW software. Moreover, data analysis was performed by using SPSS software. Subsequently, Duplex PCR was optimized for simultaneous detection of two genes. The prevalence of sat and vat genes were 75 [n: 225] and 36 [n: 106] percent, respectively. In addition, less than 4% [n: 11] of clinical isolates comprised two genes. According to the conducted research, molecular identification of Uropathogenic E .coli strains according to detection of sat gene is potentially an appropriate method and could be noted for diagnosis.
Subject(s)
Humans , Urinary Tract Infections , Escherichia coli Infections/epidemiology , Prevalence , Polymerase Chain Reaction , Bacterial Toxins/geneticsABSTRACT
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 ESBLproducing E.coli and molecular detection of CTX-M-1 in Tabriz. 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. 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. 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
ABSTRACT
Resistance to beta-lactam antibiotics along with clinical isolates is frequently resulting production of beta-lactamase enzymes. In recent years, the production of extended spectrum beta-lactamases [ESBLs] and AmpC beta-lactamase among clinical isolate especially Escherichia coli is greatly increased. On the other hand, beta lactamase genes have several subfamilies, and designing universal primers could be valuable to detect all of them. Therefore, the aim of this study was to survey prevalence of phenotypic ESBLs and detection of SHV and AmpC [CITM, FOX]-type beta-lactamase genes by using universal primers through PCR. A total of 500 clinical samples were collected from hospitals of Tehran and 200 E.coli isolates were detected by standard biochemical tests. Subsequently, these isolates were screened for beta-lactamase production by Disk diffusion method and combined disk. Resistant isolates were evaluated for molecular assessing of SHV, CITM and FOX genes by using PCR. Among entire of 200 E.coli, 128 [64%] isolates were selected via phenotypic tests for detection of bla-SHV and bla-AmpC [CITM, FOX] genes via PCR. With 95% confidence, 7[5.5%] and 13[10.2%] E.coli harbor bla-SHV and bla-CITM, respectively. Fox gene was not detected in any samples. Results were showed that complete detection of beta-lactamase enzymes is essential for resistant control and the appropriate prescription of beta-lactam drugs. So using molecular assay with phenotypic test is important