High prevalence of multidrug-resistance uropathogenic Escherichia coli strains, Isfahan, Iran

Update on Urinary Tract Infection Antibiotic Resistance-A Retrospective Study in Females in Conjunction with Clinical Data

Urinary tract infections (UTIs) represent a frequent pathology among the female population that has become more and more difficult to treat in the past decade, considering the increase in antibiotic resistance-a serious global public health problem. A cross-sectional retrospective study was conducted for six months to report an update regarding the rates of resistance and susceptibility of uropathogens necessary for optimal treatment. A total of 5487 patients were screened, of which 524 (9.54%) were female patients who met the criteria for inclusion in the study. Escherichia coli was the most common pathogen, representing 290 cases (55.34%), followed by Enterococcus spp. 82 (15.64%). Escherichia coli presented the highest resistance to amoxicillin-clavulanic acid (R = 33.1%), followed by trimethoprim-sulfamethoxazole (R = 32.41%) and levofloxacin (R = 32.06%). The highest sensitivity rates were observed for fosfomycin (S = 96.55%), followed by imipenem (S = 93.1%). Enterococcus spp. showed the highest resistance to levofloxacin (R = 50.0%), followed by penicillin (R = 39.02%). The highest sensitivity was observed for fosfomycin (S = 90.24%), linezolid (S = 89.02%), and nitrofurantoin (S = 86.58%). The second most frequent Gram-negative uropathogen was represented by Klebsiella spp., which had the highest resistance to amoxicillin-clavulanic acid (R = 35.89%), followed by levofloxacin (R = 25.64) and trimethoprim-suflamethoxazole (R = 24.35%). The most frequently associated pathology was an episode of UTI in the previous year, followed by diabetes and chronic kidney disease. Antibiotic resistance is a serious problem for all clinicians who treat UTIs. An up-to-date knowledge of antibiotic resistance rates is a major necessity to stop its evolution. Overall, the highest resistance rates were observed for aminopenicillins, fluoroquinolones, and trimethoprim-sulfamethoxazole. The best susceptibility rates were observed for fosfomycin, nitrofurantoin, and carbapenems. Our report aims to guide clinicians whenever they are forced to prescribe antibiotics empirically.

Multidrug Resistance of Escherichia coli From Outpatient Uncomplicated Urinary Tract Infections in a Large United States Integrated Healthcare Organization

Background

Urinary tract infections (UTIs) cause significant disease and economic burden. Uncomplicated UTIs (uUTIs) occur in otherwise healthy individuals without underlying structural abnormalities, with uropathogenic Escherichia coli (UPEC) accounting for 80% of cases. With recent transitions in healthcare toward virtual visits, data on multidrug resistance (MDR) (resistant to ≥3 antibiotic classes) by care setting are needed to inform empiric treatment decision making.

Methods

We evaluated UPEC resistance over time by care setting (in-person vs virtual), in adults who received outpatient care for uUTI at Kaiser Permanente Southern California between January 2016 and December 2021.

Results

We included 174 185 individuals who had ≥1 UPEC uUTI (233 974 isolates) (92% female, 46% Hispanic, mean age 52 years [standard deviation 20]). Overall, prevalence of UPEC MDR decreased during the study period (13% to 12%) both in virtual and in-person settings (P for trend <.001). Resistance to penicillins overall (29%), coresistance to penicillins and trimethoprim-sulfamethoxazole (TMP-SMX) (12%), and MDR involving the 2 plus ≥1 antibiotic class were common (10%). Resistance to 1, 2, 3, and 4 antibiotic classes was found in 19%, 18%, 8%, and 4% of isolates, respectively; 1% were resistant to ≥5 antibiotic classes, and 50% were resistant to none. Similar resistance patterns were observed over time and by care setting.

Conclusions

We observed a slight decrease in both class-specific antimicrobial resistance and MDR of UPEC overall, most commonly involving penicillins and TMP-SMX. Resistance patterns were consistent over time and similar in both in-person and virtual settings. Virtual healthcare may expand access to UTI care.

Antibiotic Resistance, Biofilm Formation and Sub-Inhibitory Hydrogen Peroxide Stimulation in Uropathogenic Escherichia coli

Uropathogenic Escherichia coli (UPEC) is the most prevalent cause of urinary tract infections (UTIs). Biofilm formation and antibiotic resistance could be high among the causative agent. The purpose of this study was to determine antibiotic resistance, biofilm production, and biofilm-associated genes, bcsA and csgD, and sub-inhibitory hydrogen peroxide (H2O2) stimulation in UPEC for biofilm formation. A total of 71 UPEC were collected from a tertiary care hospital in Kathmandu and subjected to identify antibiotic susceptibility using Kirby-Bauer disk diffusion. The biofilm formation was assessed using microtiter culture plate method while pellicle formation was tested by a tube method. In representative 15 isolates based on biofilm-forming ability, bcsA and csgD were screened by conventional polymerase chain reaction, and treated with sub-lethal H2O2. The UPEC were found the most susceptible to meropenem (90.2%), and the least to ampicillin (11.3%) in vitro and 90.1% of them were multi-drug resistant (MDR). Most UPEC harbored biofilm-producing ability (97.2%), and could form pellicle at 37°C. Among representative 15 isolates, csgD was detected only among 10 isolates (66.67%) while bcsA gene was present in 13 isolates (86.67%). This study revealed that level of biofilm production elevated after sub-lethal H2O2 treatment (P = .041). These findings suggested that the pathogens are emerging as MDR. The biofilm production is high and the majority of selected strains contained bcsA and csgD genes. Pellicle formation test was suggestive to be an alternative qualitative method to screen biofilm production in UPEC. The sub-inhibitory concentration of H2O2 may contribute in increasing biofilm formation in UPEC.

Prevalence, etiology and antibiotic resistance patterns of community-acquired urinary tract infections in Dhaka, Bangladesh

Urinary tract infection (UTI) accounts for a significant morbidity and mortality across the world and is a leading cause for antibiotic prescriptions in the community especially in developing countries. Empirical choice of antibiotics for treatment of UTI is often discordant with the drug susceptibility of the etiologic agent. This study aimed to estimate the prevalence of community-acquired UTI caused by antibiotic resistant organisms. This was a cross-sectional study where urine samples were prospectively collected from 4,500 patients at the icddr,b diagnostic clinic in Dhaka, Bangladesh during 2016–2018. Urine samples were analyzed by standard culture method and the isolated bacteria were tested for antibiotic susceptibility by using disc diffusion method and VITEK-2. Descriptive statistics were used to estimate the prevalence of community acquired UTI (CA-UTI) by different age groups, sex, and etiology of infection. Relationship between the etiology of CA-UTI and age and sex of patients was analyzed using binary logistic regression analysis. Seasonal trends in the prevalence of CA-UTI, multi-drug resistant (MDR) pathogens and MDR Escherichia coli were also analyzed. Around 81% of patients were adults (≥18y). Of 3,200 (71%) urine samples with bacterial growth, 920 (29%) had a bacterial count of ≥1.0x10⁵ CFU/ml indicating UTI. Women were more likely to have UTI compared to males (OR: 1.48, CI: 1.24–1.76). E. coli (51.6%) was the predominant causative pathogen followed by Streptococcus spp. (15.7%), Klebsiella spp. (12.1%), Enterococcus spp. (6.4%), Pseudomonas spp. (4.4%), coagulase-negative Staphylococcus spp. (2.0%), and other pathogens (7.8%). Both E. coli and Klebsiella spp. were predominantly resistant to penicillin (85%, 95%, respectively) followed by macrolide (70%, 76%), third-generation cephalosporins (69%, 58%), fluoroquinolones (69%, 53%) and carbapenem (5%, 9%). Around 65% of patients tested positive for multi-drug resistant (MDR) uropathogens. A higher number of male patients tested positive for MDR pathogens compared to the female patients (p = 0.015). Overall, 71% of Gram-negative and 46% of Gram-positive bacteria were MDR. The burden of community-acquired UTI caused by MDR organisms was high among the study population. The findings of the study will guide clinicians to be more selective about their antibiotic choice for empirical treatment of UTI and alleviate misuse/overuse of antibiotics in the community.

Molecular typification of Escherichia coli from community-acquired urinary tract infections in Mexico

One hundred and five uropathogenic Escherichia coli (UPEC) strains from patients with community-acquired urinary tract infection were characterized according to their phylogenetic groups, virulence factors, serogroups, antibiotics resistance, and genotype. The pathogenic phylogenetic groups (B2, D, and F) were found in 71.4% of the tested strains. Among them, the main uropathogenic serogroups were O8, O25, and O75, in which 97.1% of the strains had a multidrug-resistant profile. Moreover, 16 virulence genes were analyzed using a combination of PCR assays, with the fimH, irp-2, iutA, aer, iucC, PAI, sat, iroN, usp, and cnf1 genes being mainly found in pathogenic phylogroups. The E. coli O25b-ST131 clone was identified in 32% of the strains assigned to the pathogenic phylogroup B2. Our findings demonstrate that virulence genes encoding adhesin components, iron acquisition systems, toxins, and pathogenicity-associated islands were highly prevalent among the pathogenic phylogroup of UPEC strains.

The prevalence of multiple drug resistant urinary tract infections: A single-centered, observational retrospective study in King Abdulaziz Specialized Hospital, Taif, Saudi Arabia

OBJECTIVES

To determine the prevalence and patterns of antibiotic resistance, risk factors, and appropriate empiric therapy for multidrug-resistant Enterococcus (MDRE) urinary tract infections (UTIs) at King Abdulaziz Specialist Hospital (KAASH), Taif, Saudi Arabia.

METHODS

All patients attending KAASH with MDRE UTIs between January 2018 and December 2020 were enrolled in the study. After ethical approval, data were analyzed.

RESULTS

The most common causative organisms were Gram-negative and anaerobes, and the most sensitive antibiotics were ciprofloxacin and ceftriaxone.

CONCLUSION

Based on our analyses, regular culture and sensitivity should be made routine to gather information regarding susceptibility patterns, thereby reducing drug resistance in our setups.

Phage delivered CRISPR-Cas system to combat multidrug-resistant pathogens in gut microbiome

The Host-microbiome interactions that exist inside the gut microbiota operate in a synergistic and abnormal manner. Additionally, the normal homeostasis and functioning of gut microbiota are frequently disrupted by the intervention of Multi-Drug Resistant (MDR) pathogens. CRISPR-Cas (CRISPR-associated protein with clustered regularly interspersed short palindromic repeats) recognized as a prokaryotic immune system has emerged as an effective genome-editing tool to edit and delete specific microbial genes for the expulsion of bacteria through bactericidal action. In this review, we demonstrate many functioning CRISPR-Cas systems against the anti-microbial resistance of multiple pathogens, which infiltrate the gastrointestinal tract. Moreover, we discuss the advancement in the development of a phage-delivered CRISPR-Cas system for killing a gut MDR pathogen. We also discuss a combinatorial approach to use bacteriophage as a delivery system for the CRISPR-Cas gene for targeting a pathogenic community in the gut microbiome to resensitize the drug sensitivity. Finally, we discuss engineered phage as a plausible potential option for the CRISPR-Cas system for pathogenic killing and improvement of the efficacy of the system.

Activity of meropenem-vaborbactam against different beta-lactamase producing Klebsiella pneumoniae and Escherichia coli isolates in Iran

We evaluated the activity of meropenem-vaborbactam against different beta-lactamase producing Klebsiella pneumoniae and Escherichia coli isolates. In our study antibiotic susceptibility testing, double disk synergy test, modified Hodge test were applied. Detection of ESBL, AmpC, and carbapenemase genes was performed by PCR. Multilocus sequence typing (MLST) analysis was done on OXA-48 producing K. pneumoniae strains. Our results showed that among E. coli and K. pneumoniae isolates, 41.1% and 40% of strains produced ESBL, respectively. Additionally, the prevalence of AmpC producing K. pneumoniae and E. coli was 4% and 45.5%, respectively. Altogether 64.2% of K. pneumoniae strains and one E. coli isolate produced carbapenemase. Among OXA-48 producing K. pneumoniae strains ST3500 and ST2528 were detected by MLST. Based on the phenotypic results of this study, vaborbactam was an effective inhibitor on the third-generation cephalosporin-resistant isolates (P < 0.0001). Meropenem-vaborbactam combination had the highest efficacy on KPC producing strains, and it had limited activity on isolates producing OXA-48 type beta-lactamases, whereas no effect was observed on NDM-1 producing isolates. Our study provided valuable information regarding the vaborbactam inhibitory effect on β-lactamase-producing strains.

A strategy design based on antibiotic‑resistance and plasmid replicons genes of clinical Escherichia coli strains

Since antimicrobial resistance, especially β-lactam resistance genes were common in clinical Escherichia coli strains, this study had designed and developed multiplex amplification platform for rapid and accurate detection of such resistance genes in 542 clinical E. coli isolates. The obtained specimens were subjected to bacteriological examination, antimicrobial susceptibility testing, and detection of β-lactamase genes and plasmid replicons. The major virulence genes were detected by 7 groups of multiplex PCR and eight groups of multiplex PCR were designed to detect 8 different plasmid replicons including parA-parB, iteron, repA, and RNAI. It was found that most MDR isolates were co-resistant to penicillins (AMP) and fluoroquindones (LVX, CIP) and distribution of LVX and CIP resistance was significantly higher among female than male gender. RNAI (AY234375) showed the highest detection rate, followed by the iteron (J01724) and repA (M26308), indicating the relatively higher carriage rate of corresponding plasmids. Bla_OXA acquired the highest carriage rate, followed by group 2 bla_CTX-M and bla_SHV-1, indicating their prevalence among clinical E. coli. Among the β-lactamase genes, bla_OXA acquired the highest carriage rate, followed by group 2 bla_CTX-M and bla_SHV-1, indicating their prevalence among clinical E. coli. The RNAI (AY234375) showed the highest detection rate, followed by the iteron (J01724) and repA (M26308), indicating the relatively higher carriage rate of the corresponding plasmids by clinical E. coli isolates. It is shown that the developed multiplex amplification methodology is applicable to AMR detection, and such identification of plasmid replicons and β-lactamase genes may aid in the understanding of clinical E. coli isolate epidemiology.

Relationship Between Antibiotic Resistance Patterns and O-Serogroups in Uropathogenic Escherichia coli Strains Isolated from Iraqi Patients

Background: The O-antigen is one of the uropathogenic Escherichia coli (UPEC) virulence factors used as a biomarker to classify E. coli strains. Objectives: In this study, the relationship between antibiotic resistance patterns and O-serogroups was investigated in UPEC strains isolated from patients with urinary tract infections (UTIs) in southern Iraq. Methods: A total of 100 UPEC isolates from the urine specimens of patients with UTIs within the age range of 4 months to 78 years in various southern Iraqi hospitals were collected (May 2017 to January 2018) and confirmed using biochemical tests (e.g., Analytical Profile Index 20E). Antibiotic susceptibility tests were performed using the disk diffusion method according to the Clinical and Laboratory Standards Institute guidelines. The multiple polymerase chain reaction technique was applied to investigate the prevalence of O-serogroups. Results: The most frequent serogroups in the E. coli isolates were O8 (27.7%) and O25 (24.4%); however, serogroup O83 was not observed in the samples. Serogroups O75, O6, O16, and O18 had the lowest frequency (1.1%) among the examined isolates. Furthermore, 10% of the isolates did not belong to any of the examined serogroups. The phenotypic tests showed that the highest and the lowest resistance belonged to piperacillin (92%) and imipenem (5%), respectively. Serogroups O4 and O21 showed the highest drug resistance; nevertheless, serogroups O75, O18, and O1 showed the lowest drug resistance. Additionally, 94% of the isolates were resistant to three or more classes of antibiotics. Conclusions: According to the results, UPEC isolates showed high resistance to common antibiotics; however, they were sensitive to imipenem and amikacin. Serogroups O8 and O25 were the most common among UPEC isolates. Moreover, O4 and O21 showed the highest drug resistance. There was a direct relationship between antimicrobial resistance and O-serogroups in UPEC isolates.

Emergence of Highly Multidrug-Resistant Bacteria Isolated from Patients with Infections Admitted to Public Hospitals in Southwest Iran

Background

The emergence of multidrug-resistant (MDR) microorganisms causing infections is increasing worldwide and becoming more serious in developing countries. Among those, Acinetobacter species are becoming prominent.

Objectives

The aim of this study was to determine the rate of antimicrobial resistance of the bacteria causing infections, Acinetobacter species in particular, in local public hospitals in Firuzabad, Fars province, Iran.

Methods

This cross-sectional study was performed on different clinical specimens collected from patients who were suspected of infections hospitalized from March 2016 to March 2019 in local hospitals of Firuzabad, Fars province, Iran. The bacterial isolates were identified following standard microbiological methods. Clinical and Laboratory Standards Institute guidelines were used to identify the antibiotic susceptibility of these isolates.

Results

Overall, 1778 bacterial etiologies were isolated from 1533 patients diagnosed with infection. Of these, 1401 (78.8%) were Gram-negative and the remaining were Gram-positive bacteria. Escherichia coli (37.1%), Klebsiella spp. (13.9%), and Acinetobacter species (10.4%) were the most common isolated bacteria. Antibiotic sensitivity testing in this study showed a high resistance rate of Acinetobacter species to all antibiotics tested except Colistin. During the study period, the rate of infection with highly multidrug-resistant Acinetobacter species increased from 7.2% to 13.3%.

Conclusions

This study highlights the emergence of MDR bacterial agents such as Acinetobacter species as a new threat in our region. However, a decrease in the rate of infection with Pseudomonas aeruginosa was noticeable.

Antibiotic Resistance and Virulence Profiles of Escherichia coli Strains Isolated from Wild Birds in Poland

Wild animals are increasingly reported as carriers of antibiotic-resistant and pathogenic bacteria including Enterobacteriaceae. However, the role of free-living birds as reservoirs for potentially dangerous microbes is not yet thoroughly understood. In our work, we examined Escherichia coli strains from wild birds in Poland in relation to their antimicrobial agents susceptibility, virulence and phylogenetic affiliation. Identification of E. coli was performed using MALDI-TOF mass spectrometry. The antibiotic susceptibility of the isolates was determined by the broth microdilution method, and resistance and virulence genes were detected by PCR. E. coli bacteria were isolated from 32 of 34 samples. The strains were most often classified into phylogenetic groups B1 (50%) and A (25%). Resistance to tetracycline (50%), ciprofloxacin (46.8%), gentamicin (34.3%) and ampicillin (28.1%) was most frequently reported, and as many as 31.2% of E. coli isolates exhibited a multidrug resistance phenotype. Among resistance genes, sul2 (31.2% of isolates) and bla_TEM (28.1%) were identified most frequently, while irp-2 (31.2%) and ompT (28.1%) were the most common virulence-associated genes. Five strains were included in the APEC group. The study indicates that wild birds can be carriers of potentially dangerous E. coli strains and vectors for the spread of resistant bacteria and resistance determinants in the environment.

Comparative Study of ESBL Production Among Uropathogenic Escherichia coli Clinical Isolates from Pre- and Post-menopausal Women in Egypt

Urinary tract infection (UTI) is regarded one of the most frequent bacterial infections in women. Accordingly, the aim of the current study was to determine the prevalence of extended-spectrum beta-lactamase (ESBL), as well as the degree of antimicrobial resistance among premenopausal (n = 44) and postmenopausal (n = 49) women suffering from uncomplicated UTI. Urinary samples (n = 93) collected from women with UTI were tested for their antimicrobial sensitivity and assessed for ESBL production by both phenotypic and genotypic methods. Phenotypically, the presence of ESBL was observed in 64 isolates, while polymerase chain reaction detected ESBL-encoding genes in 57 isolates. The CTX-M gene was the most predominant (51.6%), followed by TEM (46.2%), and the SHV gene (17.2%). Surprisingly, all ESBL-producing Escherichia coli isolates were multidrug-resistant (MDR). To the best of our knowledge, this is the first study conducted in Egypt showing significant correlation between ESBL production, multidrug resistance and menopausal state in women. The results demonstrate alarming signal for the dissemination of ESBL genes among uropathogenic E. coli that are MDR in Egypt.

The Emergence of Quaternary Ammonium Compounds Resistance in Escherichia coli Isolated from Hospitals of Qazvin, Iran

INTRODUCTION

Escherichia coli is one of the most important agents involved in healthcare-associated infection, and resistance to quantum ammonium compounds (QACs) has become a major challenge for infection control practitioners. The aim of the current study was to determine the frequency of qacE and qacEΔ1 genes in E. coli isolated from hospitalized patients in Qazvin, Iran.

MATERIAL AND METHODS

In the current cross-sectional study, 102 E. coli were collected from hospitals of Qazvin. All bacterial isolates were identified using standard laboratory methods and the antimicrobial susceptibility was evaluated by Kirby-Baer test. The presence of qacE and qacEΔ1 genes was investigated using polymerase chain reaction (PCR) technique.

RESULTS

In this study, 65 (63.7%) isolates showed a multidrug resistance (MDR) pattern which was resistant to at least three classes of antimicrobials including ß-lactams, aminoglycosides, and fluoroquinolones. The highest rates of resistance were observed against cefotaxime (75.5%) and nalidixic acid (66.7%). The PCR showed that 5 (4.9%) isolates harbored qacE gene, 62 (60.8%) isolates qacEΔ1, and 10 (9.8%) isolates carried both genes, simultaneously. There was a significant relationship between the QACs resistance and MDR pattern (P=0.03).

CONCLUSION

This study indicated a significant resistance rate against disinfectant compounds in the studied hospitals. However, more attention should be paid to this critical issue in the infection control committees of the hospitals.

A Study on Multidrug-Resistant Escherichia coli Clinical Isolates from Different Hospitals in Greater Cairo

The biological fitness cost of antibiotic resistance is a key parameter in determining the rate of appearance and spread of antibiotic-resistant bacteria in Egypt. Our study aimed to investigate the prevalence of antibiotic resistance among Escherichia coli clinical isolates from Greater Cairo area hospitals. A total of 537 clinical isolates were recovered from samples of urine, diarrheal specimen, pus, wound culture, gastric wound, blood, drain culture, sputum, high vaginal swab, abscess, amniotic fluid, ventilator, burn swab, splenic drain culture, and unknown site of infection during different seasons. All isolates were subjected to phenotypic and genotypic susceptibility testing for colistin, nitrofurantoin, fosfomycin, and trimethoprim, quinolones, and β-lactam resistance. Our results revealed that 42.7% of the isolates harbored at least one resistance encoding gene, 10% harboring 2, 0.6% harboring 3, and 0.85% harboring 4 resistance-encoding genes. PCR reported the prevalence of resistance genes as follows: bla-SHV 13.4%, mcr-1 0.6%, qnr-A 23.8%, fos-A 1.06%, nfs-A 3.6%, and dfr-A 25.5%. We reported that three isolates carried the mcr-1 gene encoding colistin resistance from three different hospitals. Upon performing sequencing and phylogenetic analysis on the three positive mcr-1 isolates (MT890587, MT890588, and MT890589), the three isolates showed 100% identity with themselves, with some strains from Egypt and Japan, and 99.9% identity with an isolate from China.

Heterogeneity of Antibiotics Multidrug-Resistance Profile of Uropathogens in Romanian Population

Urinary tract infections (UTIs) are a leading cause of morbidity for both males and females. The overconsumption of antibiotics in general medicine, veterinary, or agriculture has led to a spike in drug-resistant microorganisms; obtaining standardized results is imposed by standard definitions for various categories of drug-resistant bacteria—such as multiple-drug resistant (MDR), extensive drug-resistant (XDR), and pan drug-resistant (PDR). This retrospective study conducted in three university teaching hospitals in Romania has analyzed urine probes from 15,231 patients, of which 698 (4.58%) presented multidrug-resistant strains. Escherichia coli was the leading uropathogen 283 (40.54%), presenting the highest resistance to quinolones (R = 72.08%) and penicillin (R = 66.78%) with the most important patterns of resistance for penicillin, sulfonamides, and quinolones (12.01%) and aminoglycosides, aztreonam, cephalosporins, and quinolones (9.89%). Klebsiella spp. followed—260 (37.24%) with the highest resistance to amoxicillin-clavulanate (R = 94.61%) and cephalosporins (R = 94.23%); the leading patterns were observed for aminoglycosides, aminopenicillins + β-lactams inhibitor, sulfonamides, and cephalosporins (12.69%) and aminoglycosides, aztreonam, cephalosporins, quinolones (9.23%). The insufficient research of MDR strains on the Romanian population is promoting these findings as an important tool for any clinician treating MDR-UTIs.

Antibiotic Resistance of Uropathogens Isolated from Patients Hospitalized in District Hospital in Central Poland in 2020

The aim of this study was to determine antibiotic resistance patterns and the prevalence of uropathogenes causing urinary tract infections (UTIs) in patients hospitalized in January–June 2020 in central Poland. Antimicrobial susceptibility testing was performed using the disk-diffusion method. Escherichia coli (52.2%), Klebsiella pneumoniae (13.7%), Enterococcus faecalis (9.3%), E. faecium (6.2%), and Proteus mirabilis (4,3%) were most commonly isolated from urine samples. E. coli was significantly more frequent in women (58.6%) (p = 0.0089) and in the age group 0–18, while K. pneumoniae was more frequent in men (24.4%) (p = 0.0119) and in individuals aged 40–60 and >60. Gram-negative species showed resistance to ampicillin. K. pneumoniae were resistant to amoxicillin plus clavulanic acid (75.0%), piperacillin plus tazobactam (76.2%), cefotaxime (76.2%), cefuroxime (81.0%), ciprofloxacin (81.0%), and trimethoprim plus sulphamethoxazole (81.0%). Carbapenems were effective against all E. coli and P. mirabilis. Some K. pneumoniae (13.6%) produced metallo-β-lactamases (MBLs). E. coli (22.6%), K. pneumoniae (81.8%), and all E. faecium were multidrug-resistant (MDR). Some E. coli (26.2%), K. pneumoniae (63.6%), and P. mirabilis (14.3%) isolates produced extended-spectrum beta-lactamases (ESBL). Vancomycin-resistant E. faecium was also found. This study showed that the possibilities of UTIs therapy using available antibiotics become limited due to the increasing number of antibiotic-resistant uropathogens.

Frequency of Antimicrobial Resistance and Class 1 and 2 Integrons in Escherichia Coli Strains Isolated from Urinary Tract Infections

Resistance to antimicrobial compounds in E. coli strains is increasing. Integrons are mobile genetic elements that lead to the spread and transfer of antibiotic resistance genes in bacteria. The aim of the present study was to determine the frequency of class 1 and 2 integrons as well as the antimicrobial resistance in E.coli strains isolated from urinary tract infections (UTIs). A total of 100 clinical isolates of uropathogenic E. coli (UPEC) were collected from patients having UTIs. These strains were identified using biochemical tests. The antibiotic susceptibility patterns of the isolated bacteria were determined in accordance with the standard method recommended by the clinical and laboratory standards institute (CLSI). The presence of class 1 and 2 integrons was determined by PCR method. The most frequent antibiotic resistance was observed to ampicillin (72%), co-trimoxazole (66%), and nalidixic acid (62%). The highest sensitivity was seen to amikacine (11%) and gentamicin (20%). The multi-drug resistance (MDR) was observed in 80% of E. coli isolates. 70% and 3% of E. coli isolate possessed class 1 and 2 integrons, respectively. Our data suggest that the antimicrobial resistance to some antibiotics as well as the frequency of class 1 and 2 integrons is very high in E. coli strains. Moreover, class 1 integrons are correlated with resistance to ampicillin, gentamicin, ciprofloxacin, co-trimoxazole, and nalidixic acid. Therefore, it is very important to monitor integron-induced drug resistance, especially class 1 integron, in order to control the urinary tract infections causing by MDR E.coli strains.

Assessment of the Presence of Resistance Genes Detected from the Environment and Selected Food Products in Benin

Gram-negative bacilli can spread from the environment and through food products. This study aimed to characterize ESBL production and virulence genes from multidrug-resistant Gram-negative bacilli isolated from specimen collected from the environment, kitchen, and food products. A total of 130 samples were collected at local markets in seven different communities in Benin (Abomey-Calavi, Ouidah, Bohicon, Abomey, Parakou, Djougou, and Grand-Popo). Samples were cultured on McConkey and ChromID^™ ESBL agar plates. The isolates were identified by the API 20E gallery. An antibiotic susceptibility test was carried out, and the detection of ESBL production and virulence-associated genes was carried out by Polymerase Chain Reaction (PCR). The data collected was coded and analyzed using GraphPad prism 7 software and Excel. The software R was used to calculate the correlation coefficient between the results of the detection of ESBL+ on agar and by the effect of the double synergy. The results showed that sixty-three (63) bacterial strains were isolated from the 130 samples, of which the dominant species was Chryseomonas luteola (10/63). The kitchen samples were the most contaminated with 36.50%. More than 40% of the isolates were resistant to at least three different classes of antibiotics. Also, blaSHV gene was detected in 33.33% (21/63) of the isolates and in all isolates of Pseudomonas aeruginosa (5/5%). 11.11% (7/63) of isolates were virulent with dominance of the fimH gene, especially with Escherichia coli (83.33%). The kitchen samples showed a high prevalence of ESBL-producing strains with fimH gene. This raises the problem of non-compliance with hygiene rules in community cooking and food handling.

PREVALENCE, DISTRIBUTION AND DETERMINANTS OF ESCHERICHIA COLI RESISTANCE TO CEFTRIAXONE IN ADULT INDOOR UTI POPULATION OF DISTRICT PESHAWAR, PAKISTAN

Background: Escherichia coliresistance to ceftriaxone in UTIs is an emerging health problem.Our objectives were to determine prevalence, distribution and determinants of E. coliresistance to ceftriaxone in adult indoor UTI population of District Peshawar, Pakistan. Materials & Methods:This cross-sectional study was conducted in Department of Medicine, Khyber Teaching Hospital, Peshawar, Pakistan from 1st January 2017 to 30th June 2017. 380 UTIs cases were selected from population at riskconsecutively.Sex and age groups were demographic, while presence of E. coli resistance to ceftriaxone was research variable. All variables were nominal.Prevalenceand distribution were analyzed by count, percentage and confidence intervals for proportion for population. Hypotheses for distribution were substantiated by chi-square goodness-of-fit and of association by chi-square test of association. Results: Out of 380 patients with UTI, 136 (35.80%) were men,244(64.20%) women, 262 (68.95%) in age group 18-45 years and 118 (31.05%) in age group 46-65 years. Frequency/ prevalence of E. coli resistance was 287/380 (75.53%, 95%CI 71.20-79.85). Out of 287 patients with E. coli resistance to ceftriaxone, 101 (26.58%) were men and 186 (48.95%) women, 198 (52.11%) in age group 18-45 years and 89 (23.42%) in age group 46-65 years. Our prevalence of E. coli resistance to ceftriaxone was higher than expected (p<.00001), our distribution by sex(p<.00125) and age groups (p<.00001) were different than expected. Presence of E. coli resistance to ceftriaxone was not associated to sex (p=.669333) and age groups (p=.975097). Conclusion:Prevalence of E. coli resistance to ceftriaxone in adult UTI population of District Peshawar, Pakistan was alarmingly high 75.53%. Prevalence was more in women than men and more in younger age group (18-45 years) than older age group (46-60 years) population.Overall prevalence of E. coli resistance to ceftriaxone was higher than expected. Distribution by sex showed higher prevalence than expected in men and lower than expected in women, and higher than expected in younger age group and lower than expected in older age group. Presence of E. coli resistance to ceftriaxone was not associated to sex and age groups respectively in adult UTI population of District Peshawar, Pakistan.

Isolation, Characterization and Genomic Analysis of a Novel Bacteriophage VB_EcoS-Golestan Infecting Multidrug-Resistant Escherichia coli Isolated from Urinary Tract Infection

Escherichia coli (E. coli) is one of the most common uropathogenic bacteria. The emergence of multi-drug resistance among these bacteria resulted in a worldwide public health problem which requires alternative treatment approaches such as phage therapy. In this study, phage VB_EcoS-Golestan, a member of Siphoviridae family, with high lytic ability against E. coli isolates, was isolated from wastewater. Its burst size was large and about 100 plaque-forming units/infected cell, rapid adsorption time, and high resistance to a broad range of pH and temperatures. Bioinformatics analysis of the genomic sequence suggests that VB_EcoS-Golestan is a new phage closely related to Escherichia phages in the Kagunavirus genus, Guernseyvirinae subfamily of Siphoviridae. The genome size was 44829 bp bp that encodes 78 putative ORFs, no tRNAs, 7 potential promoter sequences and 13 Rho-factor-independent terminators. No lysogenic mediated genes were detected in VB_EcoS-Golestan genome. Overall VB_EcoS-Golestan might be used as a potential treatment approach for controlling E. coli mediated urinary tract infection, however, further studies are essential to ensure its safety.

High Prevalence of Multidrug-Resistant and Extended-Spectrum β-Lactamase-Producing Enterobacteriaceae: A Cross-Sectional Study at Arsho Advanced Medical Laboratory, Addis Ababa, Ethiopia

Background

Multidrug-resistant Enterobacteriaceae particularly extended-spectrum beta-lactamase producers have become a major public health threat. Despite efforts to limit their spread, rates of multidrug-resistance members of the Enterobacteriaceae continue to increase throughout the world causing increased morbidity and mortality and raised costs for medical care.

Objective

The aim of this study was to determine the prevalence of multidrug resistance and extended-spectrum β-lactamase-producing Enterobacteriaceae.

Methods

Four hundred forty Enterobacteriaceae isolates from outpatients referred to Arsho Advanced Medical Laboratory were identified and assessed for their antimicrobial resistance pattern by using the automated VITEK 2 compact system. Extended-spectrum β-lactamase production was determined by the VITEK 2 automated compact system using the extended-spectrum β-lactamase test panel as per the instruction of the manufacturer.

Results

The overall resistance rates of Enterobacteriaceae against cephalosporins, aminoglycosides, and fluoroquinolones were high. Nitrofurantoin with a resistance rate of 14.3% and piperacillin/tazobactam combination with a resistance rate of 17.3% were better active against this group of Gram-negative bacteria. Out of 440 isolates of Enterobacteriaceae, 42.1% were multidrug-resistant of which 34.3% and 8.95% were extensively drug-resistant and pan-drug resistant, respectively. Among 185 multidrug-resistant Enterobacteriaceae, 63.9% of the isolates produced extended-spectrum β-lactamase of which 75.4%, 19.5%, 1.7%, 2.5%, and 0.8% were E. coli, K. pneumoniae, C. freundii, E. cloacae, and P. mirabilis, respectively.

Conclusions

The present study demonstrated high prevalence rates of multidrug-resistant and extended-spectrum-beta-lactamase-producing Enterobacteriaceae. In order to combat these problems, infection control strategy and proper antibiotic policies should be formulated.

Biogenic Synthesis of ZnO Nanoparticles and Its Potential Use as Antimicrobial Agent Against Multidrug-Resistant Pathogens

In case of Escherichia coli and Klebsiella pneumoniae infection, the increased prominence of multidrug-resistance strains has become the greatest challenge in the urinary tract disease treatment. Therefore, the 16S rRNA sequencing of multidrug-resistant strains was performed, in addition to those of plasmids and genes responsible for multidrug resistance. These strains showed containing responsible genes Sulfonamides sul1, Tetracycline Tet(A), Tetracycline Tet(B), chloramphenicol catA1, β-lactams blaSHV, and cmlA. Also, the strains demonstrated resistance to at least 10 types of antibiotics or more due to carrying various plasmids. For increasing the level of public health in daily life and treatment of multidrug-resistant bacteria, the nanomedicine was employed. Consequently, ZnO nanoparticles (ZnONPs-E) were synthesized by employing supernatant of Escherichia hermannii strain isolated from raw milk source. The E. hermannii strain produces high concentration of ZnONPs-E compared to other strains so we used it in this study. This ZnONPs-E has a minimal inhibitory concentration (MIC) ranged from the concentration 10 μg/ml to 40 μg/ml against E. coli and K. pneumoniae, respectively. The antimicrobial efficiency of ZnONPs-E was 40 µg/ml and it was superior to the reported values in literature. Moreover, SEM results evident for distorted membrane morphology, blebbing of membrane, cell elongation, and leakage of cellular contents due to ZnONPs-E activity against tested bacteria. These results indicated that the ZnONPs-E exhibited interesting antimicrobial activity against pathogenic extended-spectrum β-lactamases (ESBLs) strains. The present study revealed that the active components entered in biosynthesis of ZnONPs-E pave the way to lead its effective nano-medical and drug delivery applications.

Investigation of antibiotic resistance determinants and virulence factors of uropathogenic Escherichia coli

Multidrug-resistant (MDR) uropathogenic Escherichia coli (UPEC) are prevalent throughout the world resulting in a major public health burden. In this research, we isolated and identified 28 MDR UPEC from one university hospital in China, investigated MDR and pathogenic mechanisms by PCR, including 55 antibiotic resistance determinants (ARDs) genes, 13 genetic markers of mobile genetic elements (MGEs) and 6 virulence factors (VFs) genes. In these isolates, we identified 23 ARDs genes and 6 genetic markers of MGEs that played a key role in MDR phenotypes. In addition, we found 2 VFs genes, hofQ and ompT, which could be associated with pathogenicity and invasiveness of these strains in urinary tract infections (UTIs).

Characterization and Bio-Typing of Multidrug Resistance Plasmids From Uropathogenic Escherichia coli Isolated From Clinical Setting

Urinary tract infection is primarily caused by Escherichia coli. Multidrug resistance and their rapid dissemination in this pathogenic microbe complicate therapeutic strategies and threaten public health. Conjugation systems responsible for interbacterial transmission of antibiotic resistance are plasmid-encoded and can be classified as the P, F, and I types. Specific pili types and pili associated proteins were related to the transfer among this gram-negative organism and were thought to depend on contacts created by these structures at the time of DNA transport. In this study, conjugation system types of the plasmids that harbor multidrug resistant genes (aac-1b-cr, oqxAB, qnrB, qnrS, bla TEM, bla OXA) amongst 19 E. coli uropathogenic isolates were characterized under ciprofloxacin/ceftazidime selection individually by pili and pili associated gene types. Investigations indicated incidence of single plasmid of multiple replicon type amongst the transconjugants. bla TEM, bla CTX-M, bla OXA, aac-1b-cr, oqxAB, qnrB, qnrS genes in varied combination were observed to be successfully co-transmitted against ceftazidme/ciprofloxacin selection. Seven primer pair sets were selected that encodes pili and pili associated genes (traF, trwJ, traE, trhE, traG, pilM, pilx4) by nucleotide database search tools using annotated plasmids of different incompatibility types to assign the conjugation system type of the transmissible resistant plasmids by PCR. traF was predominant irrespective of drug selection that indicated F-type conjugation system was responsible for transmission of resistant plasmids which results in the rapid dissemination of antibiotic resistance in the isolates screened. Therefore this is a first report of its kind that investigated pili and pili associated genes to bio-type multidrug resistant plasmids and their transmission in clinical settings amongst uropathogenic E. coli circulated in the eastern part of India.

Antibiotic Resistance Among Uropathogenic Escherichia coli

Urinary tract infections (UTIs) belong to the most common community-acquired and nosocomial infections. A main etiological factor of UTIs is uropathogenic Escherichia coli (UPEC). This review describes the current state of knowledge on the resistance of UPEC to antibiotics recommended for the treatment of UTIs based on the available literature data. Nitrofurantoin and fosfomycin are recommended as first-line therapy in the treatment of uncomplicated cystitis, and the resistance to these antimicrobial agents remains low between UPEC. Recently, in many countries, the increasing resistance is observed to trimethoprim-sulfamethoxazole, which is widely used as the first-line antimicrobial in the treatment of uncomplicated UTIs. In European countries, the resistance of UPEC to this antimicrobial agent ranges from 14.6% to 60%. The widespread use of fluoroquinolones (FQs), especially ciprofloxacin, in the outpatients is the cause of a continuous increase in resistance to these drugs. The resistance of UPEC to FQs is significantly higher in developing countries (55.5–85.5%) than in developed countries (5.1–32.0%). Amoxicillin-clavulanic acid is recommended as first line-therapy for pyelonephritis or complicated UTI. Resistance rates of UPEC to amoxicillin-clavulanic acid are regionally variable. In European countries the level of resistance to this antimicrobial ranges from 5.3% (Germany) to 37.6% (France). Increasing rates of UPEC resistance to antimicrobials indicate that careful monitoring of their use for UTI treatment is necessary.

In-Vitro Biofilm Formation and Antimicrobial Resistance of Escherichia coli in Diabetic and Nondiabetic Patients

Background

Diabetic patients are more susceptible to urinary tract infection compared to nondiabetic patients, Escherichia coli being the most common uropathogen causing UTI. Unreasonable and incorrect antibiotic prescription for UTI in these patients may induce the development of antibiotic-resistant urinary pathogens resulting in delayed recovery and longer hospitalization. In addition to these, biofilm forming capacity of the pathogen may worsen the problem. The main aim of this cross-sectional study (conducted from March to September 2015) is to detect the biofilm forming capacity of UTI causing micro-organisms and compare the antibiotic resistance pattern of Escherichia coli, the most common cause of UTI, which will help the physician in choosing the best antibiotic.

Method

Total of 1,099 clean-catch mid stream urine (CCMSU) was processed by standard microbiological technique; 182 were from the diabetic group and 917 nondiabetic. Following identification, all isolates were subjected to antibiotic susceptibility testing using modified Kirby-Bauer disc diffusion method. In-vitro biofilm forming capacity of the isolates were detected by Microtitre plate method. The data were analyzed using SPSS software 16.

Result

Urinary tract infection was found to be significantly higher in diabetic patients (42.9%) compared to nondiabetic patients (17.4%) with Escherichia coli as the most common uropathogen in both diabetic and nondiabetic groups. Similarly, UTI was more common in elderly population (29.5%). Imipenem, nitrofurantoin and amikacin were found to be the most effective drug for uropathogenic E. coli in both diabetic and nondiabetic patients, whereas amoxicillin, ciprofloxacin, and cotrimoxazole were least effective. Of the total bacterial isolates, 43.3% showed positive results for in-vitro biofilm production by the Microtitre plate method. A significantly higher resistance rate was observed among biofilm producing E. coli for quinolones, cotrimoxazole, and third generation cephalosporin ceftriaxone. Most of the biofilm producers (79.5%) were found to be MDR (p-value 0.015).

Conclusion

Elderly populations with diabetes are at a higher risk of UTI. Higher biofilm production and resistance to in-use antimicrobial agents in this study render its inefficacy for empirical treatment and point out the importance of biofilm screening to ensure the effective management of infection.

Phylogeny, sequence-typing and virulence profile of uropathogenic Escherichia coli (UPEC) strains from Pakistan

Background

Escherichia coli lineage ST131 predominates across various spectra of extra-intestinal infections, including urinary tract infection (UTI). The distinctive resistance profile, diverse armamentarium of virulence factors and rapid global dissemination of ST131 E. coli makes it an intriguing pathogen. However, not much is known about the prevalence and genetic attributes of ST131 lineage in Pakistan.

Methods

We estimated prevalence and genetic attributes of E. coli ST131 isolates causing UTI among 155 randomly selected samples. Samples were analyzed for phylogenetic grouping, O-typing and fumC/fimH typing. Isolates were further tested for the ESBL and virulence factors using PCR.

Results

Overall, 59% of the UPEC isolates belonged to the phylogenetic group B2, followed by D = 28%, B1 = 8% and A = 5%. Among 18 different Sequence-types, ST131 was the dominant lineage (n = 71; 46%) out of which 72% of the isolates were assigned to the phylogenetic group B2, while 61% adhered to the serogroup O25b. FumC/fimH typing confirmed 49% of the ST131 as H30 sub-types. In this study, significant numbers of the identified ST131 isolates were MDR and 42% showed ESBL phenotypes, out of which 37% carried bla-_CTX-M-15. Moreover, different virulence factors were detected in following percentages: fimH,155(100%), iutA 86 (55%), feoB 76 (49%), papC 75 (48%), papGII 70 (45%), kpsMTII 40 (26%), papEF 37 (24%), fyuA 37 (24%), usp 22 (14%), papA 20 (13%), sfa/foc20 (13%), hlyA 18 (12%), afa 15 (10%), cdtB 11 (7%), papGI 6 (4%), papGIII 6 (4%), kpsMTIII 4 (3%) and bmaE2 (1%).

Conclusion

Conclusively, this study provides important insight into the genetic and virulence attributes of pandemic MDR ST131 strains involved in UTIs. It also highlights higher prevalence of ST131-O25b-H30 UPEC isolates in patients, which was previously unreported from this part of globe.

Virulence factors and antimicrobial resistance in uropathogenic Escherichiacoli strains isolated from cystitis and pyelonephritis

Background/aim

The aim of this study was to investigate the prevalence of virulence genes as well as patterns of antibiotic resistance in cystitis and pyelonephritis uropathogenic Escherichia coli (UPEC) isolates.

Materials and methods

Two hundred UPEC isolates were collected from hospitalized patients with pyelonephritis (n = 50) and cystitis (n = 150) in Shafa Hospital in Iran. Antimicrobial susceptibility and ESBL production were determined with confirmatory tests. Polymerase chain reaction assay was performed to determine the prevalence of virulence genes in UPEC strains.

Results

Of a total 200 UPEC isolates, the highest and lowest resistance rates to antibiotics were for cephalexin (74%) and nitrofurantoin (9%), respectively. Of these isolates, 72 (36%) and 128 (64%) strains were ESBL-positive and ESBL-negative, respectively. The frequency of fimH, papC, and hly was 64%, 38%, and 12%, respectively. The most commonly identified virulence gene in ESBL-positive and ESBL-negative strains was fimH 46 (23%) and 86 (43%), respectively. The hlyA gene was more prevalent among patients with pyelonephritis than cystitis.

Conclusion

The frequency of virulence genes was not significantly different between pyelonephritis and cystitis UPEC strains in the studied patients, but the prevalence rates of hlyA and papC genes were higher among UPEC strains isolated from inpatients compared to outpatients; hence, they could be considered as useful targets for prophylactic interventions.

Relationships between Virulence Factors and Antimicrobial Resistance among Escherichia coli Isolated from Urinary Tract Infections and Commensal Isolates in Tehran, Iran

Objectives

Uropathogenic Escherichia coli (UPEC) are the major cause of urinary tract infections (UTIs). Here, we determined whether sensitivity to antibiotics was related to the prevalence of iron scavenging genes, or to biofilm and hemolysis formation.

Methods

A total of 110 UPEC and 30 E coli isolates were collected from the urine of UTI patients and feces of healthy individuals without UTI, respectively. The presence of iron receptor genes and phenotypic properties were evaluated by polymerase chain reaction and phenotypic methods, respectively. Susceptibility to routine antibiotics was evaluated using the disc diffusion method.

Results

The prevalence of iron scavenging genes ranged from 21.8% (ireA) to 84.5% (chuA) in the UPEC. Resistance to ceftazidime and cefotaxime was significantly correlated with the presence of fyuA and iutA iron genes. Biofilm production was significantly associated with the prevalence of fyuA and hma iron genes. A higher degree of antibiotic resistance was exhibited by isolates that produced biofilms than by their non-biofilm producing counterparts.

Conclusion

Our study clearly indicates that biofilm production is associated with antibiotic resistance, and that iron receptors and hemolysin production also contribute to reduced antibiotic sensitivity. These results further our understanding of the role that these virulence factors play during UPEC pathogenesis, which in turn may be valuable for the development of novel treatment strategies against UTIs.

An evaluation of multidrug-resistant Escherichia coli isolates in urinary tract infections from Aguascalientes, Mexico: cross-sectional study

BACKGROUND

Uropathogenic Escherichia coli (UPEC) are one of the main bacteria causing urinary tract infections (UTIs). The rates of UPEC with high resistance towards antibiotics and multidrug-resistant bacteria have increased dramatically in recent years and could difficult the treatment.

METHODS

The aim of the study was to determine multidrug-resistant bacteria, antibiotic resistance profile, virulence traits, and genetic background of 110 E. coli isolated from community (79 isolates) and hospital-acquired (31 isolates) urinary tract infections. The plasmid-mediated quinolone resistance genes presence was also investigated. A subset of 18 isolates with a quinolone-resistance phenotype was examined for common virulence genes encoded in diarrheagenic and extra-intestinal pathogenic E. coli by a specific E. coli microarray.

RESULTS

Female children were the group most affected by UTIs, which were mainly community-acquired. Resistance to trimethoprim-sulfamethoxazole, ampicillin, and ampicillin-sulbactam was most prevalent. A frequent occurrence of resistance toward ciprofloxacin (47.3%), levofloxacin (43.6%) and cephalosporins (27.6%) was observed. In addition, 63% of the strains were multidrug-resistant (MDR). Almost all the fluoroquinolone (FQ)-resistant strains showed MDR-phenotype. Isolates from male patients were associated to FQ-resistant and MDR-phenotype. Moreover, hospital-acquired infections were correlated to third generation cephalosporin and nitrofurantoin resistance and the presence of kpsMTII gene. Overall, fimH (71.8%) and fyuA (68.2%), had the highest prevalence as virulence genes among isolates. However, the profile of virulence genes displayed a great diversity, which included the presence of genes related to diarrheagenic E. coli. Out of 110 isolates, 25 isolates (22.7%) were positive to qnrA, 23 (20.9%) to qnrB, 7 (6.4%) to qnrS1, 7 (6.4%) to aac(6')lb-cr, 5 (4.5%) to qnrD, and 1 (0.9%) to qnrC genes. A total of 12.7% of the isolates harbored blaCTX-M genes, with blaCTX-M-15 being the most prevalent.

CONCLUSIONS

Urinary tract infection due to E. coli may be difficult to treat empirically due to high resistance to commonly used antibiotics. Continuous surveillance of multidrug resistant organisms and patterns of drug resistance are needed in order to prevent treatment failure and reduce selective pressure. These findings may help choosing more suitable treatments of UTI patients in this region of Mexico.

Global research output in antimicrobial resistance among uropathogens: A bibliometric analysis (2002-2016)

OBJECTIVES

Antimicrobial resistance (AMR) among uropathogens contributes to treatment failure. Research in AMR among uropathogens is important to establish treatment options. This study assessed global research trends in AMR among uropathogens.

METHODS

SciVerse Scopus was used to retrieve relevant documents for the period 2002-2016. Only journal articles were included in the analysis. Analysis of author keywords was carried out using VOSviewer.

RESULTS

A total of 1087 journal articles were retrieved with an h-index of 50. The number of publications increased noticeably in the past decade. Analysis of subject areas of retrieved documents showed that 275 (25.3%) articles were in molecular biology/genetics/microbiology/immunology, 197 (18.1%) were in pharmacological/therapeutic approaches for treatment of urinary tract infections and 615 (56.6%) were in epidemiology/public health. Terms such as multidrug-resistant and extended-spectrum β-lactamases (ESBLs) appeared more frequently in documents published in the period 2012-2016. The mean number of authors per article was 5.3. Most active authors in this field were from Japan. The USA ranked first with 148 documents (13.6%), followed by India (97; 8.9%) and Iran (84; 7.7%). The top productive institution was Tehran University of Medical Sciences (21 publications), followed by Kobe University in Japan (20 publications). The Journal of Antimicrobial Chemotherapy ranked first with 33 publications.

CONCLUSION

Research in AMR among uropathogens showed a noticeable increase in the past decade. Reports of increasing incidence of resistance among uropathogens were published from different parts of the world. Empirical therapy should be based on updated research in AMR.

Prevalence and Antibiotic Susceptibility Pattern of Extended Spectrum Beta Lactamases Producing Escherichia Coli Isolated from Outpatients with Urinary Tract Infections in Babol, Northern of Iran

Received 08 November 2017 Accepted 15 February 2018 The incidence of community-acquired UTIs due to extended-spectrum beta-lactamase (ESBL) producing E. coli isolates, has increased worldwide and is considered a great problem in the treatment of infections. The aim of this study was to determine the prevalence of ESBL producing E. coli isolates in urine samples of outpatients in Babol, North of Iran. A total of 3 699 urine samples from outpatients referred to Yahyanejad Hospital, Babol, Iran, were collected during 15 months, from March 2016 to June 2017. The samples were processed for bacterial culture using conventional methods, while antimicrobial susceptibility testing for E. coli isolates was performed by the disc diffusion method. The prevalence of ESBL producing E. coli isolates were assessed by Double-Disc tests. Of 3699 tested sample, 201 samples showed the growth of pathogens and among them, 106 isolates (52/7%) were E. coli. The rate of ESBL producing E. coli isolates was 25/4%.The majority (81/5%) of the isolates were from females. High percent resistance was found against ceftazidime, cefotaxime, ceftriaxone, cefixime and ciprofloxacin, ranging from 61-100%, while the highest percent susceptibility was seen to meropenem, piperacillin- tazobactam (100%), followed by nitrofurantoin and amikacin (91%). The high prevalence of ESBL producing E. coli isolates from outpatients calls for the need to aware of this increasing resistance between uropathogens and update bacterial susceptibility data and to set up our empirical therapy accordingly.

Antimicrobial Resistance Pattern and Spectrum of Multiple-drug-resistant Enterobacteriaceae in Iranian Hospitalized Patients with Cancer

Background:

Nosocomial infections are one of the most leading causes of morbidity and mortality in patients with cancer. The emergence of multiple-drug-resistant (MDR) strains of Gram-negative bacteria causing nosocomial infection has become a serious concern in cancer patients. Therefore, the present study aimed to determine the spectrum and antibiotic resistance pattern of Gram-negative bacteria related nosocomial infections among Iranian cancer patients.

Materials and Methods:

This descriptive cross-sectional study was conducted during the 6 months from December 2015 to May 2016 in two tertiary care centers located in Isfahan and Arak Province. Gram-negative bacteria obtained from different clinical specimens from hospitalized patients with cancer and were identified using standard microbiological methods. Antibiotic susceptibility pattern was determined by the disk diffusion method according to the Clinical and Laboratory Standards Institute (CLSI) recommendation.

Results:

Of totally 259 culture positive cases, Escherichia coli showed the highest isolation rate (60.6%) followed by Klebsiella pneumoniae (26.6%) and Proteus spp (11.2%). The rate of MDR isolates were 91.5% (237/259). Overall, the most frequent source of bacterial isolation was urinary tract infection (65.6%) followed by skin and soft-tissue infection (23.6%). The antibiotic susceptibility results showed meropenem (MEN) and ceftazidime as the most effective antibiotics for E. coli, K. pneumoniae, and Proteus spp. isolates. Moreover, MEN was the most effective antibiotic against MDR isolates.

Conclusion:

The study findings showed a significant distribution of MDR Gram-negative bacteria which may increase the burden of healthcare-associated infections in cancer patients. Although, carbapenem can be considered as effective agents toward MDR strains for empirical antibiotic therapy in our region.

Biofilm Formation in Nonmultidrug-resistant Escherichia coli Isolated from Patients with Urinary Tract Infection in Isfahan, Iran

Background:

Escherichia coli is a Gram-negative, opportunistic human pathogen in which increasing antibiotic resistance is a great concern for continued human survival. Although biofilm formation is a mechanism that helps E. coli to survive in unfavorable conditions, according to the importance of biofilm formation in developing the antibiotic resistance here, we studied the relation between antibiotic resistance and in vitro qualitative rating method biofilm formation in E. coli isolated from patients with urinary tract infection (UTI).

Materials and Methods:

The clinical isolates of E. coli (n = 100) were collected from urine of patients with UTI attending Isfahan Alzahra hospital. The strains were confirmed as E. coli using biochemical tests and molecular method. The Kirby-Bauer disk diffusion tests were done according to the Clinical and Laboratory Standards Institute protocol, and the biofilm synthesis was performed by microplate method. The binary logistic test was applied and P < 0.05 was considered statistically significant.

Results:

Our results showed a high outbreak of multidrug-resistant (MDR) E. coli strains (73%) and the highest resistance was observed toward ampicillin. The prevalence of biofilm producer isolates was 80% that 29% produced strong biofilm. The distribution of non-MDR isolates was high among strong biofilm producers, which shows a significant negative correlation between biofilm production and MDR pattern (P < 0.001).

Conclusions:

We found a negative correlation between MDR phenotype and biofilm formation capacity. This transmits the concept that more antibiotic susceptibility of strong biofilm producers may be due to the reduced exposure to multiple antibiotics.

Emerging nanotechnology based strategies for diagnosis and therapeutics of urinary tract infections: A review

At present, various diagnostic and therapeutic approaches are available for urinary tract infections. But, still the quest for development of more rapid, accurate and reliable approach is an unending process. The pathogens, especially uropathogens are adapting to new environments and antibiotics day by day rapidly. Therefore, urinary tract infections are evolving as hectic and difficult to eradicate, increasing the economic burden to the society. The technological advances should be able to compete the adaptability characteristics of microorganisms to combat their growth in new environments and thereby preventing their infections. Nanotechnology is at present an extensively developing area of immense scientific interest since it has diverse potential applications in biomedical field. Nanotechnology may be combined with cellular therapy approaches to overcome the limitations caused by conventional therapeutics. Nanoantibiotics and drug delivery using nanotechnology are currently growing areas of research in biomedical field. Recently, various categories of antibacterial nanoparticles and nanocarriers for drug delivery have shown their potential in the treatment of infectious diseases. Nanoparticles, compared to conventional antibiotics, are more beneficial in terms of decreasing toxicity, prevailing over resistance and lessening costs. Nanoparticles present long term therapeutic effects since they are retained in body for relatively longer periods. This review focuses on recent advances in the field of nanotechnology, principally emphasizing diagnostics and therapeutics of urinary tract infections.

Drug-resistant gram-negative uropathogens: A review

Urinary tract infection(UTI) caused by Gram-negative bacteria is the second most common infectious presentation in community medical practice. Approximately 150 million people are diagnosed with UTI each year worldwide. Drug resistance in Gram-negative uropathogens is a major global concern which can lead to poor clinical outcomes including treatment failure, development of bacteremia, requirement for intravenous therapy, hospitalization, and extended length of hospital stay. The mechanisms of drug resistance in these bacteria are important due to they are often not identified by routine susceptibility tests and have an exceptional potential for outbreaks. Treatment of UTIs depends on the access to effective drugs, which is now threatened by antibiotic resistant Gram-negative uropathogens. Although several effective antibiotics with activity against highly resistant Gram-negatives are available, there is not a unique antibiotic with activity against the high variety of resistance. Therefore, antimicrobial susceptibility tests, correlation between clinicians and laboratories, development of more rapid diagnostic methods, and continuous monitoring of drug resistance are urgent priorities. In this review, we will discuss about the current global status of drug-resistant Gram-negative uropathogens and their mechanisms of drug resistance to provide new insights into their treatment options.

Multidrug- and Extensively Drug-Resistant Uropathogenic Escherichia coli Clinical Strains: Phylogenetic Groups Widely Associated with Integrons Maintain High Genetic Diversity

In recent years, an increase of uropathogenic Escherichia coli (UPEC) strains with Multidrug-resistant (MDR) and Extensively Drug-resistant (XDR) profiles that complicate therapy for urinary tract infections (UTIs) has been observed and has directly impacted costs and extended hospital stays. The aim of this study was to determine MDR- and XDR-UPEC clinical strains, their virulence genes, their phylogenetic groups and to ascertain their relationship with integrons and genetic diversity. From a collection of 500 UPEC strains, 103 were selected with MDR and XDR characteristics. MDR-UPEC strains were mainly associated with phylogenetic groups D (54.87%) and B2 (39.02%) with a high percentage (≥70%) of several fimbrial genes (ecpA, fimH, csgA, and papGII), an iron uptake gene (chuA), and a toxin gene (hlyA). In addition, a moderate frequency (40–70%) of other genes (iutD, tosA, and bcsA) was observed. XDR-UPEC strains were predominantly associated with phylogenetic groups B2 (47.61%) and D (42.85%), which grouped with ≥80 virulence genes, including ecpA, fimH, csgA, papGII, iutD, and chuA. A moderate frequency (40–70%) of the tosA and hlyA genes was observed. The class 1 and 2 integrons that were identified in the MDR- and XDR-UPEC strains were associated with phylogenetic groups D, B2, and A, while the XDR-UPEC strains that were associated with phylogenetic groups B2, D, and A showed an extended-spectrum beta-lactamase (ESBL) phenotype. The modifying enzymes (aadA1, aadB, aacC, ant1, dfrA1, dfrA17, and aadA4) that were identified in the variable region of class 1 and 2 integrons from the MDR strains showed resistance to gentamycin (56.25 and 66.66%, respectively) and trimethoprim-sulfamethoxazole (84.61 and 66.66%, respectively). The MDR- and XDR-UPEC strains were distributed into seven clusters and were closely related to phylogenic groups B2 and D. The diversity analysis by PFGE showed 42.68% of clones of MDR-UPEC and no clonal association in the XDR-UPEC strains. In conclusion, phylogenetic groups including virulence genes are widely associated with two integron classes (1 and 2) in MDR- and XDR-UPEC strains.