جستجوی مقالات مرتبط با کلیدواژه « escherichia coli » در نشریات گروه « پزشکی »

Cefiderocol is a siderophore cephalosporin with unique cell-penetrating abilities against multidrug-resistant (MDR) Gram-negative bacteria, especially carbapenem-resistant strains. This study aimed to evaluate the prevalence and susceptibility profiles of Cefiderocol on carbapenem-resistant uropathogenic Escherichia coli and Klebsiella pneumoniae isolates among hospitalized patients.

One hundred twenty-nine patients more than 72 h admitted to hospitals participated from Feb. 2021 to Dec. 2022. Urine samples were examined to identify uropathogenic K. pneumoniae and E. coli isolates based on microscopic morphology, cultural and biochemical methods. The carbapenemase production in the isolates was evaluated using modified Hodge tests and PCR. The MIC of Cefiderocol against carbapenemase-producing isolates was evaluated according to CLSI-2021 guidelines.

According to phenotypic and genotypic tests, among forty-two E. coli isolates (71.19%) were carbapenemase positive, 38 isolates had the blaOXA gene (90.47%), and among twenty-four K. pneumoniae isolates 96% contained the blaKPC gene. In MIC determination 55.24% of carbapenem-resistant E. coli isolates were inhibited with ≤0.5 μg/ml of Cefiderocol, while only two strains (8.33%) of K. pneumoniae isolates showed resistance to the Cefiderocol (MIC90=2 μg/ml).

The present results demonstrate that the emergence of carbapenem-resistant uropathogenic bacteria poses a critical health threat to society. Based on the results, Cefiderocol demonstrated efficacy against carbapenem-resistant clinical isolates at low concentrations.

Salivary abomasum disease (SAD) is a devastating disease causing significant mortality in Iranian goat and sheep herds. Understanding the causative agents is essential for developing effective preventive measures. This study investigated the potential role of Shiga toxin-producing Escherichia coli (STEC) in SAD pathogenesis.

We isolated E. coli from kid goats aged 3-30 days experiencing a sudden, acute illness characterized by gait imbalance, and death within 48 hours during the kidding season. Following isolation, we employed multiplex PCR to identify the presence of Shiga toxin genes (Stx1 and Stx2) associated with virulence in STEC strains.

E. coli was isolated from 30 (75%) out of 40 animals. Notably, 7 (23.3%) isolates harbored the Stx2 gene, while only one isolate (3.3%) possessed the Stx1 gene.

These findings suggest a potential role for STEC, particularly strains carrying the Stx2 gene, in the development of SAD and multiple abomasal hemorrhages, in kid goats. The presence of Shiga toxin genes in a significant proportion of E. coli isolates highlights the importance of further research to elucidate their  contribution to SAD pathogenesis and inform the development of targeted interventions.

Biological contamination of foods is a serious problem for human health. Animal and animal products may be contaminated by these biological and chemical contaminants. One of the most important causes of foodborne illness in humans is Escherichia coli. Fluoroquinolones can be used as a suitable treatment for enteric infections in food-producing livestock. We aimed to evaluate the current status of resistance of E. coli strains isolated from animals and animal products to fluoroquinolone in Iran.

 A systematic search was conducted using the Web of Science, PubMed, Embase, Google Scholar, and Scopus databases from 2000 to Oct 2020. Nineteen studies were selected based on the inclusion criteria and analysis by Comprehensive Meta-Analysis.

Based on the data analysis, The rates of antibiotic resistance in animal strains were as follows: Flumequine (75.1%), Enrofloxacin (55.2%), Danofloxacin (48.1%), Ciprofloxacin (48.4%), and Norfloxacin (52.9%). Next, the rates of quinolone resistance among E. coli strains isolated from animal products were Norfloxacin (45.5%), Ciprofloxacin (44.5%), and Enrofloxacin (60.9%). Based on the funnel plots and Egger's test, there was no significant publication bias.

We finally concluded that antibiotic resistance in commensal E. coli is related to the overuse of antibiotics in livestock, especially fluoroquinolones.

Urinary tract infections (UTI) are a leading cause of bacterial infections in humans.The widespread use of antibiotics has resulted in the emergence of antibiotic-resistant microorganisms. Hence, the current study was conducted to investigate the antibiotic sensitivity pattern of uropathogens in UTI.

A total of 642 urine samples were collected from suspected UTI patients and tested microbiologically. Antimicrobial susceptibility tests were performed for the isolated pathogens using the Kirby- Bauer disk diffusion method.

Out of 642 urine samples, 308 (48%) were found to exhibit significant bacteriuria. Females had a higher rate of UTI (68%) than males (32%), with a higher prevalence in the middle-aged group, while males reported a higher prevalence in the elderly group, which was statistically significant. The most common organism was Escherichia coli (57.2%), followed by Klebsiella pneumoniae (26.3%), Pseudomonas aeruginosa (8.4%), Proteus spp. (3.6%), Enterococcus spp. (2.6%), and Staphylococcus aureus (1.9%). UTI were more common in middle-aged female patients (31 to 45 years), while in males, high prevalence was seen in older patients (>45 years). Meropenem, Gentamicin, Nitrofurantoin, and Co-Trimoxazole were amongst the most sensitive drugs against E.coli and K.pneumoniae.

Due to the irrational and injudicious use of antibiotics, commonly isolated uropathogens have a changing resistance pattern, resulting in reduced treatment effectiveness. This could be overcome by routine antimicrobial resistance surveillance, antimicrobial stewardship measures, and culture-guided therapy.

Implementing Hazard Analysis and Critical Control Point (HACCP) management across the supply chain is promoted globally to ensure the safety of marine food products due to their rapid quality deterioration. However, many seafood retail stores deviate from adopting these practices. Therefore, in this study, we aimed to create a flowchart based on HACCP and validate it in retail stores.

Chub mackerel (Scomber japonicus), scallops (Patinopecten yessoensis), and whiteleg shrimp (Litopenaeus vannamei) specimens were purchased from a supermarket from August to December 2020. The handling information of these products from receipt to sales was obtained to prepare an HACCP plan for retail stores. Groups adhering to and deviating from flowchart conditions were categorized as Critical Control Point (CCP)-compliant and CCP-deviant, respectively. Four samples of each product for each condition were analyzed. Bacterial viability was evaluated using the flat agar culture method. Escherichia coli and Vibrio parahaemolyticus were detected using the Brilliant Green-Lactose-Bile and material point methods, respectively. Product freshness was assessed by determining K-values using High-Performance Liquid Chromatography. Results were compared using Student’s t-test.

At elevated storage temperatures, bacterial growth rates were higher in chub mackerel and whiteleg shrimp than those in scallops. E. coli was not detected in any sample, whereas V. parahaemolyticus was detected in scallops and whiteleg shrimp but not in chub mackerel. CCP-deviant refrigerated scallops had increased V. parahaemolyticus counts; however, it did not differ between the frozen scallop and whiteleg shrimp. K-values increased more rapidly in CCP-deviant chub mackerel, whiteleg shrimp, and refrigerated scallops, but not in frozen scallops. Inadequate temperature control during display and sale markedly deteriorated the quality of marine products.

Setting CCPs for marine food product display and sale while controlling temperature can preserve product quality. The flowchart created in this study can be broadly used for marine retail stores.

Fresh pasta filata cheese is considered as one of the most important foods in the Venezuelan diet. It is typically produced by small-scale producers using raw milk. The objective of this research was to molecularly characterize the pathogenic potential of Escherichia coli strains isolated from pasta filata cheese manufactured and marketed in Venezuela.

In the period between January and March of 2019, a total of 36 strains of E. coli were isolated from a variety of pasta filata cheeses including 17 samples of mozzarella, 16 of telita, and 3 of guayanés. These strains were isolated according to the Venezuelan Commission of Industrial Standards (COVENIN) and identified by conventional methods (biochemical and phenotypic tests). Antimicrobial susceptibility was determined using the disk diffusion technique. Phylogenetic grouping and detection of virulence genes were performed by Polymerase Chain Reaction amplification. Diversity and genetic relationships were determined by Rep-PCR.

All strains were susceptible to the tested antibiotics. Phylogroup A (n=19) was the most frequent (52.8%), followed by groups D (n=11; 30.6%), and B1 (n=2; 5.6%). The majority of isolates carried at least two virulence genes, one coding for adhesion mechanisms (fimH) and the other for iron uptake (fyuA). Only one strain of phylogroup A presented a profile consisting of four virulence genes (fimH, fyuA, kpsMT II, and papAH). Four strains that could not be classified according to Clermont's scheme carried resistance genes as well. A heterogeneous population structure was observed by Rep-PCR of the strains.

Results support the hypothesis that the E. coli strains isolated from the three types of pasta filata cheeses manufactured and marketed in Venezuela have identical characteristics and virulence factors to Extraintestinal Pathogenic E. coli strains observed in animals and humans, posing a potential health risk. Therefore, it is essential to improve hygienic and sanitary controls at all stages of cheese production and to implement measures for epidemiological surveillance of potentially pathogenic bacterial strains present in Venezuelan, artisanal pasta filata cheeses.

Extended-spectrum beta-lactamases (ESBLs) are enzymes in bacteria that resist many antibiotics. Detection of ESBLs production is important as it's a marker of colonization and potential transfer to other patients. We studied the antibiotic susceptibility, biofilm formation capacity, and prevalence of ESBLs of opportunistic bacteria including K. pneumoniae and E. coli. The isolates capable of biofilm formation were analyzed among 100 E. coli and 104 K. pneumoniae isolates.

This process involved collecting and identifying bacterial samples, testing antibiotic susceptibility, detecting ESBLs phenotypes, and multidrug-resistance (MDR) isolates, assessing biofilm formation capability, and evaluating results through statistical analysis.

The susceptibility tests for discs were performed following the guidelines outlined by the Clinical Laboratory Standards Institute in 2023 (CLSI). K. pneumoniae exhibits inherent resistance to ampicillin, while 80 (80%) strains of E. coli have been reported to be resistant to ampicillin. Additionally, 50 K. pneumoniae isolates and 41 E. coli isolates were found capable of forming a biofilm. Seven of E. coli (17.07%), and seven of K. pneumoniae (14%) isolates could form a mighty biofilm. It was observed that the strongest resistance in the isolates that formed strong biofilm was related to tetracycline with 5 (7.2%) resistance in K. pneumonia and 7 (7%) resistance in E. coli. Furthermore, 47 (47%) of E. coli, and 21 (20.2%) of K. pneumoniae isolates were classified as ESBLs producers, and 52 (50%) K. pneumoniae and 72 (72%) E. coli isolates were classified as MDR.

Considering the role of biofilm in the transfer of genes, appropriate health policies, and the correct administration of effective antibiotics can help in prevention.

The green synthesis of metal oxide nanoparticles using plant extracts can effectively replace traditional chemical synthesis methods. In present paper, we describe the formation of zinc oxide (ZnO) nanoparticles (NPs) using Pistacia vera soft peel extract. Synthesis of plant-based nanoparticles possesses numerous advantages compared to the conventional physicochemical approaches with different applications in biology and medicine. In the present study Pistacia vera peel extract was used to synthesize ZnO NPs. To investigate the optical and structural features of ZnO nanoparticles synthesized by Pistacia vera peel extract, X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, ultraviolet-visible spectrophotometer (UV-Vis), and scanning electron microscope (SEM) were used. The off-yellow hue of the reaction mixture indicated that ZnO NPs were formed. The presence of Pistacia vera peel extract-mediated ZnO NPs was revealed by UV-Visible peaks at 422 nm. In addition, an XRD pattern confirmed the formation of spherical structure nanomaterials with an average size of 42 nm along with the XRD pattern matching the JCPDS card. The Existence of bioactive functional groups effective in reducing the bulk of zinc sulfate to ZnO NPs was further confirmed by FTIR. The SEM images revealed the spherical shape, and the size of nanoparticles, which was within the range of 31.14 to 48 nm. To examine the antibacterial potential of ZnO NPs, a paper disc diffusion technique was used against Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus clinical strains in terms of the inhibition zone. In addition, the radical scavenging assay was done by the DPPH test. The green synthesized Pistacia peel extract-mediated ZnO NPs demonstrate striking antioxidative activity at 100 μg mL–1. Using NaBH4, nanoscale zinc oxide can remove methylene blue in only 150 seconds. Furthermore, they remove 98% of methylene blue in 14 minutes under UV light.

Urinary tract infection (UTI) is a serious issue affecting both men and women resulting from the invasion of microbial agents into the urinary system. This study aimed to investigate the antimicrobial activity of Lactobacillus casei (L. casei) against Klebsiella pneumoniae (K. pneumoniae) and Escherichia coli (E. coli) isolated from UTI.

In this study, 100 urine specimens were obtained from medical laboratories in western Tehran. E. coli and K. pneumoniae isolates were identified and subsequently confirmed using polymerase chain reaction (PCR). Antibiotic susceptibility patterns were determined using the disk diffusion method. The antimicrobial activity of L. casei against these strains (four multidrug-resistant isolates from each species) was then evaluated using the agar well diffusion method.

From 100 urine specimens, 76 E. coli and 14 K. pneumoniae isolates were identified. Antimicrobial susceptibility testing revealed that imipenem and nitrofurantoin were the most effective antibiotics against E. coli, while amikacin demonstrated the highest efficacy against K. pneumoniae. In the agar well diffusion assay, L. casei generated growth inhibition zones measuring 19.8 mm ± 3 for E. coli and 20.3 mm ± 4 for K. pneumoniae.

Lactobacillus casei demonstrates notable antimicrobial efficacy against both E. coli and K. pneumoniae, suggesting its potential as an alternative therapeutic option for UTIs.

 Escherichia coli is one of the main causes of various diseases worldwide, whose multidrug-resistant strains have caused many public health problems by producing extended-spectrum β-lactamases (ESBLs). The resistance rate varies in different regions. Thus, it is necessary to identify ESBL-producing strains in each region and their antibiotic sensitivity in order to find appropriate treatment options. Hence, the present study aimed to detect the ESBL-producing E. coli strains and their antimicrobial susceptibility pattern in Tabriz, Iran.

 This study was conducted at the Imam Reza Hospital in Tabriz from November 20, 2022, to April 20, 2023. A total of 400 E. coli isolates were collected from different clinical specimens. Antimicrobial susceptibility testing was performed by the disk diffusion method. ESBL-producing isolates were detected by the double-disc synergy test method according to the Clinical and Laboratory Standards Institute (CLSI) guidelines.

 Out of 400 E. coli isolates, 211 (52.75%) were obtained from females, and 189 (47.25%) belonged to males. The mean age of patients was 52.1±27.9 years. Overall, 279 (69.75%) were confirmed as ESBL producers. These producers were mainly recovered from outpatients. The highest antibiotic resistance was observed to ceftriaxone (86.25%) and tetracycline (80.75%), and the least antibiotic resistance was related to imipenem (8%) and amikacin (16.25%), respectively. The rate of antibiotic resistance among ESBL producers was higher than among non-ESBLs.

 The present study reported a high prevalence of ESBL-producing E. coli among patients referring to Imam Reza hospital in Tabriz. Carbapenems, aminoglycosides, and nitrofurantoins were confirmed as the most efficient drugs for these bacteria, whereas cephalosporins, fluoroquinolones, and sulfonamides were the least effective agents.

Hospital-acquired infections (HAIs) are a major healthcare problem in hospitalized patients, especially in developing countries, where they affect millions of patients and cause high mortality rates. This study aimed to investigate multidrug-resistant bacterial strains in NIs at Imam Khomeini University Hospital in Urmia, Iran.

This cross-sectional study was conducted using a convenience sampling method. The study population comprised all positive clinical samples from HAIs registered in the laboratory of Imam Khomeini Hospital, Urmia, Iran, in 2019. Bacteria were identified by culturing the samples on blood agar and MacConkey agar, followed by performing standard biochemical tests. Antibiotic susceptibility testing was carried out using the disk diffusion method, in accordance with CLSI guidelines.

Of the 607 positive samples, the most common microorganisms isolated were Escherichia coli (27.5%), Acinetobacter baumannii (18.5%), and Klebsiella pneumoniae (15.2%). The distribution of resistance to the number of antibiotics in bacterial isolates from the samples showed that 19.8% of them were resistant to one antibiotic and 13.2% were resistant to three antibiotics. 40.5% of the samples showed no resistance to antibiotics.

This study highlights the critical issue of HAIs and the prevalence of multidrug-resistant bacteria in Urmia, Iran. Urgent measures, including improved hygiene, accurate diagnostics, appropriate antibiotic use, and stakeholder education, are essential. Establishing a robust HAI surveillance system is also recommended. Future efforts should aim at understanding and mitigating the spread of these pathogens.

To explore the prevalence and characteristics of secondary bacterial infections among patients suffering from mucormycosis following COVID-19 infection.

We conducted a cross-sectional, retrospective analysis from March 2020 to April 2022 at Imam Khomeini Hospital Complex in Tehran. The study included patients with histopathologically confirmed mucormycosis and documented secondary bacterial infections. We extracted and analyzed data from hospital records using SPSS software, version 26.

The study comprised 27 patients, with a predominance of females (70.4%) and an average age of 56 years. The majority of these patients (63%) had pre-existing diabetes mellitus. The severity of their COVID-19 infections varied. Treat- ment regimens included immunosuppressive drugs and antibiotics. Rhinocerebral mucormycosis was the most common form observed. The predominant secondary infections involved the urinary tract, respiratory system, bloodstream (bacteremia), and soft tissues, with resistant strains of Acinetobacter baumannii, Escherichia coli, and Klebsiella pneumoniae being the most frequently identified microorganisms. Notably, cases of bacteremia and pneumonia exhibited a higher mortality rate. Ultimately, 55.6% of patients were discharged, while 44.4% succumbed to their infections.

Patients recovering from COVID-19 with mucormycosis are significantly susceptible to secondary bacterial infections, particularly those with diabetes mellitus or those undergoing immunosuppressive therapy. Such infections com- pound the morbidity and mortality risks in this vulnerable patient cohort.

 Drymaria cordata is used traditionally against hyperglycemia. In this research the methanol (DCM), hexane (DCH), and water (DCW) extracts of D. cordata were investigated for their metabolite profiling, antioxidant, antibacterial, and carbohydrate hydrolyzing enzyme inhibitory activities.

 The antidiabetic activities of the extracts were investigated using the α-amylase and α-glucosidase (carbohydrate-hydrolyzing enzymes) inhibition assays and yeast glucose uptake assays. Antibacterial investigation of D. cordata extracts was done against methicillin-resistant Staphylococcus aureus (MRSA) and β-lactam-resistant Escherichia coli. The zone of inhibition and minimum inhibitory concentration (MIC) were observed.

 GC-MS metabolite profiling revealed the presence of stearyl aldehyde, henicosanal, glycidyl palmitate, eicosane, phytol, octacosanal, and neophytadiene. The DCM extract had a higher phenolic (168.19 ± 3.34 mg gallic acid equivalent/g), flavonoid (843 ±11.55 mg rutin equivalents/g), and ferric reducing potential (556.083 ± 6.51 mg ascorbic acid equivalent/g) than the DCH and DCW extracts. Also, DCM showed its greatest scavenging activity with a minimum IC50 value using the ABTS assay. DCM extract had the highest zone of inhibition and lowest MIC value against E. coli and S. aureus. Carbohydrate-hydrolyzing enzymes were inhibited, with DCM extract having minimum IC50 values of 714.66 µg/ml and 508.94 µg/ml. Yeast glucose uptake assays confirmed the highest efficacy of DCM extract for glucose uptake by yeast cells.

 Drymaria cordata, especially DCM, has the potential to be considered an effective phytopharmaceutical drug for the treatment of oxidative stress, bacterial infections, and type 2 diabetes.

Biofilm is a community of bacteria surrounded by extracellular polymeric substances, providing protection against harsh environmental conditions and serving as a major cause of various infections. The objective of this study was to evaluate the effects of various antibiotics on Escherichia coli biofilms obtained from nosocomial infections, as well as to explore the correlation between virulence factors and the formation of biofilms.A total of 140 Escherichia coli isolates from nosocomial infections were analyzed for antibiotic susceptibility using the Kirby-Bauer method. Biofilm formation was assessed using the crystal violet microplate technique, with a focus on identifying biofilm-associated genes such as afa, pap, sfa, agg, and fimH. Based on CLSI criteria, Imipenem exhibited the highest sensitivity at 99.28%, whereas Cotrimoxazole showed the highest resistance at 91.43%. Among the isolates, 41.43% did not form biofilms, while 21.43%, 19.29%, and 17.85% formed weak, moderate, and strong biofilms, respectively. A correlation was found between biofilm formation and antibiotic resistance. The frequency of fimH, Pap, Sfa, afa, and agg genes among the isolates was 59.28%, 26.42%, 17.85%, 8.57%, and 0.00%, respectively. The study suggests that high antibiotic resistance may be associated with strong or moderate biofilm production. The ability of E. coli strains to form biofilms may play a crucial role in managing nosocomial infections.

Investigating multidrug resistance and TEM and SHV broad-spectrum beta-lactamase genes in Escherichia coli bacteria isolated from patients with urinary tract infections is very useful to improve the treatment of infection and prevent the failure of treatment of urinary tract infections.The aim of this study was to investigate multidrug resistance and TEM and SHV broad-spectrum beta-lactamase genes in Escherichia coli bacteria isolated from patients with urinary tract infections.

In this study, 188 strains of Escherichia coli, which cause urinary tract infections in Alborz province, were studied. Urine samples were cultured on EMB and Blood Agar media. Differential tests were performed for final identification. ESBL-producing strains were identified, PCR was performed to survey the abundance of ESBL-producing genes.

Based on the results of the disk diffusion and Double-disk synergy testS, 82 (43.6%) strains were determined as the final producer of ESBL. out of these isolates, the frequency of SHV, TEM, and CTX genes measured 64.3%, 55.9%, and 21.4%, respectively. These results showed that 12 (14.28%) of Escherichia coli isolated have all genes, 26 (30.95%) had 2 genes and 36 (42.85%) had one gene.

According to the results, it was found that imipenem with the lowest resistance is the best drug in the treatment, and carbapenems are the best drug for treating diseases caused by Escherichia coli. The results of the current study may be useful in replacing ESBL enzyme resistance screening with more modern sensitivity measurement methods such as MIC and Etest.