Microbiology
Sorour Farzi; Reza Ranjbar; Mohammad Niakan; Mohammad Hossein Ahmadi
Abstract
Background & Objective: Escherichia coli (E. coli) is a leading cause of urinary tract infections becoming resistant against beta-lactams and cephalosporins through different mechanisms, including ESBL production due to the presence of ESBL specific genes, including blaCTX-M and blaTEM. The purpose ...
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Background & Objective: Escherichia coli (E. coli) is a leading cause of urinary tract infections becoming resistant against beta-lactams and cephalosporins through different mechanisms, including ESBL production due to the presence of ESBL specific genes, including blaCTX-M and blaTEM. The purpose of the present study was to detect the uropathogenic E. coli strains producing the ESBL.Methods: A total of 100 isolates of uropathogenic E. coli were randomly selected in a period of 6 months and their resistances to a number of antibiotics including amoxicillin, amikacin, gentamicin, ciprofloxacin, ceftazidime, cefotaxime, ceftriaxone, ceftizoxime, nalidixic acid, and nitrofurantoin were determined. Then, DDT test was used to detect the presence of ESBL. Finally, the presence of blaCTX-M and blaTEM resistance genes was analyzed by PCR method.Results: The resistance profile of bacterial isolates to the antibiotics was as follows: amoxicillin: 16.7%, amikacin: 7.8%, gentamicin: 20.3%, ciprofloxacin: 35.5/%, ceftazidime: 35.0%, cefotaxime: 40.0%, ceftriaxone: 41.3%, nalidixic acid: 64.0%, nitrofurantoin: 9.7%, and ceftizoxime: 100%. Of these, 28 isolates (28%) were reported to be resistant to cefotaxime, ceftazidime, and ceftriaxone. In DDT test, 21 ESBL positive cases (21%) were detected. PCR results showed that the presence of blaCTX-M and blaTEM genes in the isolates were 21% and 20%, respectively. Conclusion: Regarding the production of ESBL by some E. coli isolates, phenotypic detection of ESBL-producing isolates is routinely suggested in the laboratories. Likewise, the treatment regimen should be selected regarding the ESBL production to avoid treatment failure.
Zohreh Nozarian; Alireza Abdollahi
Abstract
Background and Objectives: Urinary tract infections (UTI) are one of the most common infectious diseases with different microbial agent and antimicrobial resistant pattern in hospitalized patients and outpatients. In order to assess the adequacy of therapy, knowledge of prevalence and resistance pattern ...
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Background and Objectives: Urinary tract infections (UTI) are one of the most common infectious diseases with different microbial agent and antimicrobial resistant pattern in hospitalized patients and outpatients. In order to assess the adequacy of therapy, knowledge of prevalence and resistance pattern of the bacteria is necessary. The main aim of this study was to evaluate the prevalence and the antimicrobial resistance pattern of main bacterial responsible for UTI in order to establish an appropriate empirical therapy. Methods: All urine samples were referred to Imam Hospital Laboratory, Tehran, Iran during 2011-2012, urine culture isolated and bacteria were identified and the profile of antibiotic susceptibility was characterized. Result: From 1851 urine cultures, UTI was more frequent in woman (68%) E. coli was as usual the most common pathogen implicated in UTI. Most susceptibility was to imipenem (98.9%). nitroforantoin (96%) and amikacin (94.1%) and increased resistance to penicillin (66.6%), nalidixic acid (62.1%) ampicilin (60.1%) and cotrimoxazole 54.3%. Discussion: The most common isolated pathogen was E. coli. According to antibiogram susceptibility, the recommended antimicrobial drugs are nitroforantoin and imipenem. nalidixic acid and cotrimoxazole are not recommended because drug resistance is high.
Mohammad Rahbar; Massoud Hajia; Mona Mohammadzadeh
Volume 7, Issue 1 , January 2012, , Pages 32-37
Abstract
Background and Objective: Early diagnosis of Streptococcus agalactiae remains difficult, since symptoms are very nonspecific. Its frequency has not been completely investigated in urinary tract pathogen of pregnant ant and non pregnant women in Iran. The aim of this study was determining the frequency ...
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Background and Objective: Early diagnosis of Streptococcus agalactiae remains difficult, since symptoms are very nonspecific. Its frequency has not been completely investigated in urinary tract pathogen of pregnant ant and non pregnant women in Iran. The aim of this study was determining the frequency of Group B Streptococci in female patients.
Materials and Methods: A Total of 11800 urine specimens were received from female out-patients admitted during June till December 2010. Group B Streptococci isolates were confirmed by typical colony morphology, and identified by differential tests as well as by the growth characteristics in chromoagar. A provisional urinary tract infection diagnosis was defined by the presence of single group B Streptococci (>10 CFU/liter) with at least one of urinary tract infection symptom. Susceptibility testing was carried out by disk diffusion method.
Results: Of all specimens 498 specimens (4.22%) yielded significant bacteriuria caused by group B Streptococci. The mean age of these patients were 26.6 + 19.37. Pregnant patients were 3.82% and the rest were non-pregnant. Antibiotic susceptibility test revealed that vancomycin, clindamycin and cefazolin had the lowest and penicillin showed the highest resistant rate.
Conclusion: Pattern onantibiotic susceptibility test showed high resistant rate to some antibiotic that made it difficult for pregnant patients, although its frequency was low. It was not possible to compare the antibiotic susceptibility pattern of pregnant women with non-pregnant because of the low number of pregnant women registered in this study.
Ali Jazayeri Moghadas; Gholamreza Irajian
Volume 4, Issue 3 , June 2009, , Pages 105-108
Abstract
Background and Objectives: Urinary tract infection is one of the most common bacterial infections in the human population, and more frequent infection during pregnancy. With notice to this point that most of urinary tract infections during pregnancy are asymptomatic, they could lead to serious ...
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Background and Objectives: Urinary tract infection is one of the most common bacterial infections in the human population, and more frequent infection during pregnancy. With notice to this point that most of urinary tract infections during pregnancy are asymptomatic, they could lead to serious complications such as prematurity, low-birth weight, hypertension, and higher fetal mortality rates ifuntreated. This study was aimed to determine the prevalence of asymptomatic bacteriuria, bacterial agents and their antibiotic susceptibility pattern in pregnant womenattendingSemnan public health centers during 2007-8. Patients and Methods: In this descriptive cross sectional study,pregnant women attending Semnan public health centers during May 2007 and June 2008 were investigated. Clean catch mid stream urine samples were collected and cultured on Eosin Metylene Blue agar and Blood agar by calibrated loop method. Suspected colonies were identified, antibiotic susceptibility test was done. Results: Of 297 samples, 10 (3.3%) were positive for asymptomatic urinary tract infection. The dominant bacterial isolate was Escherichia coli (70%). The antibiotic susceptibility was observed to ciprofloxacin, ceftazidime and cefotaxime (80%), the most resistance was amoxicillin- clavulanic acid (90%). Conclusion: Frequency of asymptomatic UTI in pregnant women in this study is significantly lower than similar studies. Antibiotic susceptibility rate to using antibiotics do not show significant differences with most other studies.
Maliheh Khoddami; Maryam Farzaneh; Manigeh Garooni Anaraki
Volume 1, Issue 3 , June 2006, , Pages 117-120
Abstract
Background and Objective: This study was undertaken to assess the ability of standard urinalysis (UA) and hemocytometer white blood cell (WBC) counts for the diagnosis of urinary tract infection (UTI) in patients with urinary symptoms. Materials and Methods: A total of 600 patients with symptoms of urinary ...
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Background and Objective: This study was undertaken to assess the ability of standard urinalysis (UA) and hemocytometer white blood cell (WBC) counts for the diagnosis of urinary tract infection (UTI) in patients with urinary symptoms. Materials and Methods: A total of 600 patients with symptoms of urinary tract infection were enrolled in this prospective study. Standard UA, hemocytometer WBC counts, and quantitative urine culture tests were performed on the specimens. The results of UA and hemocytometry were compared with urine culture findings to determine the accuracy of these two methods in the diagnosis of UTI. In this regard, sensitivity, specificity, positive and negative predictive values, accuracy, and likelihood ratios were determined for each of the screening tests. Results: There were 91 positive urine cultures with at least 105 bacteria per milliliter. Sixtyseven patients were female. The results of UA and hemocytometry were as follows: sensitivity 64.8% and 77%; specificity 89% and 90.3%; positive predictive value (PPV) 51.3% and 58.8%; negative predictive value (NPV) 93.4% and 95.6%; and accuracy 85.3% and 88.4% respectively. Conclusion: Although hemocytometer WBC counts have a higher sensitivity, specificity, and positive predictive value than standard UA, the differences are not statistically significant (p>0.05).
