Multidrug-Resistant of Escherichia coli and Salmonella spp. Strains in Chicken Feces Intended for Consumption in Open Spaces of Ouagadougou, Burkina Faso

Resistant bacteria can be transmitted to humans through feces or contaminated meat from local chickens. Bacterial strains were isolated from the intestinal contents of 400 local chicken samples from various sales sites. These strains were then characterized using bacteriological and biochemical methods to identify resistant strains. In a study conducted in Ouagadougou, we systematically collected chicken fecal samples from 20 locations across the city, followed by isolation and identification of Salmonella spp. using specific enrichment and culture methods, as well as Escherichia coli. Bacterial strains were characterized using antibiotic resistance profiles were determined through agar diffusion tests, revealing sensitivity or resistance to a range of antibiotics based on established scientific criteria. The results showed that out of the 400 samples collected, 81.25% and 63.5% were contaminated by Escherichia coli and Salmonella spp., respectively. Among these, 86.15% of identified Escherichia coli and 50.78% of Salmonella spp. displayed resistance to at least one tested antibiotic. Among 280 Escherichia coli isolates identified resistant to at least one antibiotic, 31.07% were resistant to cefotaxime (CTX), 20.35% to ceftazidime (CAZ), 21.07% to ceftriaxone (CTR), 75% to amoxicillin clavulanic acid (AMC), 23.57% aztreoname (ATM) and 27.14% were resistant to imipenem (IMP). In the case of the 129 Salmonella spp. isolates resistant to at least one tested antibiotic, 34.88% were resistant to CTX;41.08% to CAZ;35.65% to CTR, 92% to AMC, 39.53% to ATM and finally 47.28% were resistant to IMP. Our study revealed high prevalence of resistance in bacterial strains isolated from local chickens sold outdoors in Ouagadougou. These findings raise significant public health concerns, due to the possible transmission of these resistant strains to humans through the consumption of contaminated meat, thus complicating the treatment of bacterial infections.

Performance Parameters:Demobilization Antibiotic Resistant Bacteria(ARB)and Carrying Genes(ARG)in Wastewater Disinfection

The UV irradiation is used for removing Antibiotic Resistant Bacteria(ARB)and Antibiotic Resistance Genes(ARG)from wastewater treatment.Bacteriophages are viruses that infect within bacteria,are recognized for bacterial control.The influence of some parameters in quantification and performance influencing of pathogen demobilization could be considered in disinfection of wastewater.The comparison of Polyvalent phage(NE1)versus Coliphage(NE4)in suppressing a bacterium Escherichia coli(NDM-1:b-lactam-resistant)with UV irradiation was observed the efficacy in reduction of cells in the disinfection and parameter process.The results with the effect of UV-C irradiation on NDM-1 infected with 1%of NE4 showed a decrease of cells from 8×10^(6)to 2×10^(5)in 60 min with UV-C dose.The NDM1(E.coli)was infected with 1%of NE4(Polyvalent Phage)under magnetic stirring for 1 h,the cells count was 8×10^(6).After 1 h in UV-C e×posure,the cells number reached 3×10^(5).The NDM1 that was e×posed in 1 h of UV-C irradiation and then was infected with 1%of NE4.Cells counting were done 24 h after this procedure.These cells were e×posed in UV-C and showed a reduction in the number of cells from 1×10^(8)to 4×10^(5)after 60 min.The results indicate that bacteriophages can mitigate bacteria species,and combined the conventional water disinfection technologies that can support the microbial safety control strategies.

Genotyping Characteristics of Human Fecal Escherichia coli and Their Association with Multidrug Resistance in Miyun District, Beijing

Objective To explore the genotyping characteristics of human fecal Escherichia coli(E. coli) and the relationships between antibiotic resistance genes(ARGs) and multidrug resistance(MDR) of E. coli in Miyun District, Beijing, an area with high incidence of infectious diarrheal cases but no related data.Methods Over a period of 3 years, 94 E. coli strains were isolated from fecal samples collected from Miyun District Hospital, a surveillance hospital of the National Pathogen Identification Network. The antibiotic susceptibility of the isolates was determined by the broth microdilution method. ARGs,multilocus sequence typing(MLST), and polymorphism trees were analyzed using whole-genome sequencing data(WGS).Results This study revealed that 68.09% of the isolates had MDR, prevalent and distributed in different clades, with a relatively high rate and low pathogenicity. There was no difference in MDR between the diarrheal(49/70) and healthy groups(15/24).Conclusion We developed a random forest(RF) prediction model of TEM.1 + baeR + mphA + mphB +QnrS1 + AAC.3-IId to identify MDR status, highlighting its potential for early resistance identification. The causes of MDR are likely mobile units transmitting the ARGs. In the future, we will continue to strengthen the monitoring of ARGs and MDR, and increase the number of strains to further verify the accuracy of the MDR markers.

Multidrug Resistant Pattern and Plasmid Detection of Escherichia coli from Various Sources within the University of Port Harcourt

Multi-drug resistance (MDR) in Enterobacteriaceae poses critical public health threat in Nigeria and the global world. This resistant mechanism might be plasmid mediated or chromosomal. Escherichia coli are Gram negative pathogen with a global distribution rate. The study was carried out to determine MDR and plasmid profiling of E. coli isolates from urine, feaces and poultry litter. The samples were cultured on eosine methylene blue agar and incubated for 24 hours at 37°C. Results obtained showed a percentage prevalence of 30% for the urine samples which were the most prevalent, while the prevalence of E. coli from the feacal and poultry litter was 8% and 28% respectively. Identified E. coli were screened for antibiotic susceptibility by Kirby Bauer diffusion method. The results on susceptibility of E. coli to tested antibiotics before plasmid curing showed 100% resistance to cefuroxime and augumentin, while 75% resistance was observed in gentamicine, ciprofloxacin and ofloxacine. Cefixime and cefdazidime resistance were 62.5% on E. coli and the least resistance was observed in nitrofurantion (25%). The poultry litter and urine isolates recorded lower resistance level to antibiotics, compared to the feacal isolates. After plasmid curing the percentage of resistance reduced. The only antibiotics that responded positively was nitrofurantion, with high sensitivity of 87% for feacal isolate, 100% for urine isolates, and 78% for poultry litter isolates after plasmid curing. Twenty (20) of the thirty seven (37) isolates were still resistant to more than two antibiotics after the plasmid curing. Of the twenty isolates, 18 (90%) were found to harbor single plasmid, while 2 (10%) did not possess plasmid. This study concludes that nitrofurantion was the most effective antibiotics on Escherichia coli and plasmids were responsible partly for resistance.

Phenotypic and molecular characterizations of multidrug-resistant diarrheagenic E.coli of calf origin

Escherichia coli has become one of the most important causes of calf diarrhea.The aim of this study is to determine the patterns of antimicrobial resistance of E.coli isolates from six cattle farms and to identify prominent resistance genes and virulence genes among the strains isolated from the diarrhea of calves.Antimicrobial susceptibility tests were performed using the disk diffusion method,and PCR was used to detect resistance and virulence genes.The prevalence of multidrug resistant(MDR)E.coli was 77.8%in dairy cattle and 63.6%in beef cattle.There were high resistance rates to penicillin(100%,100%)and ampicillin(96.3%,86.4%)in E.coli from dairy cattle and beef cattle.Interestingly,resistance rate to antimicrobials and distribution of resistance genes in£coli isolated from dairy cattle were higher than those in beef cattle.Further analysis showed that the most prevalent resistance genes were blojm and oodAl in dairy cattle and beef cattle,respectively.Moreover,seven diarrheagenic virulence genes(irp2,fyuA,Stx1,eoeA,F41,K99 and STa)were present in the isolates from dairy cattle,with a prevalence ranging from 3.7%to 22.22%.Six diarrheagenic virulence genes(irp2,fyuA,Stx1,eoeA,hylA and F41)were identified in the isolates from beef cattle,with a prevalence ranging from 2.27%to 63.64%.Our results provide important evidence for better exploring their interaction mechanism.Further studies are also needed to understand the origin and transmission route of£coli in cattle to reduce its prevalence.

How Growth Ability of Multidrug-Resistant Escherichia coli Is Affected by Abiotic Stress Factors

The ability of multidrug-resistant Escherichia coli to adapt and grow in a wide range of different environmental conditions may be crucial to the global spread of antimicrobial resistance. The aim of this study was to evaluate the survival ability of 54 multidrug-resistant E. coli strains, isolated from three different biotopes (clinical setting, gull intestine, river water) when subjected to variations in pH (from 3 to 11) and salinity (from 0.5% to 6% of NaCl) and to nutrient deprivation. The growth of each isolate as well as of a reference strain was assessed during 168 h in every varying condition. Slight variations in the growth ability under some abiotic stress factors were recorded among the isolates from the different biotopes. Multidrug-resistant isolates from gull feces were found to be the more tolerant to environmental abiotic changes, while isolates from river water were the less tolerant. In addition, it was notorious that the carriage of antimicrobial resistance has a clear fitness cost in comparison with the susceptible (reference) strain, highlighting the necessity of reducing the selective pressure exerted by antibiotics. This study underlines the ecological hardness of multidrug-resistant E. coli isolates with a consequent ability to reach and colonize new host and environments.

Potential antibacterial activity of berberine against multi drug resistant enterovirulent Escherichia coli isolated from yaks(Poephagus grunniens) with haemorrhagic diarrhoea

Objective:To evaluate the antimicrobial efficacy of berberine,a plant alkaloid.Methods:Five multi-drug resistant（MDR） STEC/EPEC and five MDR ETEC isolates from yaks with haemorrhagic diarrhoea were selected for the study.Antibacterial activity of berberine was evaluated by broth dilution and disc diffusion methods.The binding kinetics of berberine to DNA and protein was also enumerated.Results:For both categories of enterovirulent Escherichia coli（E.roli） isolates, berberine displayed the antibaclerial effect in a dose dependent manner.The MIC50 of berberine chloride for STEC/EPEC isolates varied from 2.07μM to 3.6μM with a mean of（2.95±0.33）μM where as for ETEC strains it varied from 1.75 to 1.96μM with a mean of（1.87±0.03）μM. Berberine bind more tightly with double helix DNA with Bmax and Kd of（24.68±2.62） and（357.8±57.8）,respectively.Berberine reacted with protein in comparatively loose manner with Bmax and Kd of（18.9±3.83） and 【286.2±113.6),respectively.Conclusions:The results indicate clearly that berberine may serve as a good antibacterial against multi drug resistant E.coli.

农贸市场食品来源大肠埃希菌的耐药性及其ESBL耐药基因的研究

目的:调查云南省保山市农贸市场售卖畜禽肉蛋和蔬菜超广谱β-内酰胺酶(Extended-Spectrumβ-Lactamase,ESBL)大肠埃希菌污染情况,研究样品分离获得的大肠埃希菌ESBL耐药基因类型。方法:收集农贸市场食品样本,分离鉴定样品中的大肠埃希菌并进行药敏试验,扩增大肠埃希菌的ESBL基因,对扩增产物进行测序和同源性比对分析。结果:245份食品样本中分离获得大肠埃希菌75株,其中产ESBL大肠埃希菌25株。对ESBL耐药基因测序结果进行系统发育分析,发现耐药基因为CTX-M型,CTX-M-15序列有9株,占比为36%;CTX-M-14有16株,占比为64%。结论:肉类和蔬菜携带ESBL大肠埃希菌,多重耐药菌及其耐药基因可能通过食品在社区传播。

Escherichia coli Pathotypes in Children with Acute Diarrhea in an Informal Settlement in Nairobi, Kenya

Diarrhea is among the leading causes of morbidity and mortality in children aged Escherichia coli (DEC) accounts for 30% - 40% of childhood diarrhea cases. To identify the pathotypes involved in diarrheal outbreaks in Kenya, we analyzed archived E. coli isolates from children E. coli confirmation and antimicrobial susceptibility testing were done using the VITEK®2 instrument. Pathotype identification was performed via conventional polymerase chain reaction. Of 175 E. coli isolates, 48 (27%) were DEC pathotypes, with enteroaggregative E. coli (EAEC) predominating (71%, 34/48). Enterohemorrhagic (EHEC) and enteropathogenic E. coli (EPEC) represented 19% and 10% of isolates, respectively. Enteroinvasive and enterotoxigenic pathotypes were not identified. All DEC isolates were susceptible to amikacin, ertapenem, imipenem, meropenem and tigecycline. Conversely, most (>80%) isolates were resistant to ampicillin, ampicillin-sulbactam and sulfamethoxazole-trimethoprim. Half of all EAEC and EPEC strains were resistant to cefazolin while half of EHEC isolates were resistant to ciprofloxacin and moxifloxacin. In total, 18 resistance phenotypes were identified with “ampicillin-cefazolin-ampicillin/ sulbactam-sulfamethoxazole/trimethoprim” predominating (33%, 16/48). The majority (81%) of DEC isolates were multidrug-resistant, with extended-spectrum beta-lactamase production identified in 8% of these isolates. This study highlights the predominance of Enteroaggregative E. coli and multidrug resistance of DEC pathotypes. Studying the epidemiology of diarrheal disease and antimicrobial resistance surveillance, will aid in identifying dominant etiological agents of diarrhea and newly emerging resistant strains in informal settlements.

Isolation and Identification of Serotype O101 Bovine Pathogenic Escherichia coli with Multidrug Resistance

[Objective]The paper was to isolate and identify a multidrug-resistance bovine pathogenic Escherichia coli. [Method]The dead cases of calf diarrhea were collected from a large-scale beef cattle farm,and the isolated pathogen was conducted molecular identification,serological identification,drug sensitivity test,and mice pathogenicity test,respectively. Targeted therapy was undertaken thereafter to herds. [Result] One strain of bovine pathogenic E. coli,serotype O101 with strong multidrug resistance and high pathogenicity to mice,was successfully isolated. It was used to develop sensitive drug for timely treating follow-up diarrhea calves,and successfully controlled calf diarrhea in the farm. [Conclusion]The results provide a basis for effective prevention and control of bovine colibacillosis.

Antibiotic resistant Esherichia coli strains from seafood and its susceptibility to seaweed extracts

Objective:To determine the prevalence and antibiotic resistance of Escherichia coli(E. coli),in seafood obtained from Cuddalore and Parangipettai fish landing centres.Also,to identify the susceptibility of E.coli against predominant seaweeds red alga Kappaphycus alvarezii(K.alvarezii) and brown alga Padina boergessenii(P.boergessenii) extracts as sulfated polysaccharides and polyphenols respectively.Methods:A total of 48 samples(Two stations Cuddalore and Parangipettai,Tamil Nadu,India).Sampling area are fish landing centre where fishes caught from sea and estuary,seafood processing plants(packing and ice packed fishes) and local fish markets(fish samples).After isolation totally 80 strains were analyzed for its antimicrobial resistance and sensitivity against commercially 10 antibiotics.The ampicillin resistant E.coli CE21 was identified through molecular techniques as I6S rDNA sequencing. Two seaweeds K.alvarezii and P.boergessenii were screened lor antibacterial activity against 12 antibiotic resistant E.coli strains.Results:Totally 48 swabbed samples from two different fish handling area were characterized for total bacterial and E.coli count.Mostly,the E.coli strains were isolated from fish local market and seafood processing plants before and after packaging process.In that maximum 56.25%strains were resistant to ampicillin and the minimum 2.5%strains were resistant to chloramphenicol.Therefore,the E.coli CE21 was identified through molecular techniques E.coli(GenBank accession number GU065251),The MIC value for polyphenol extract was slightly less than sulfated polysaccharides.E.coli strain isolated from Parangipettai was considerably increased MIC value that Cuddalore.Conclusions: The polyphenol and sulfated polysaccharides showed promising inhibitory response against all antimicrobial resistant E.coli strains and in particular the inhibitory response of ampicillin resistant E.coli.

Detection of aac(3)IIc, aac(6)Ib, armA Genes Coding for Escherichia coli Resistance to Aminoglycosides in Burkina Faso

Background and Prupose: Antibiotic resistance is a major global health concern. In addition to the existing data on the prevalence of bacterial resistance to antibiotics, there are patchy data on bacterial resistance to aminoglycosides in Burkina Faso. In this study, we determined the prevalence of aminoglycoside resistance genes in E. coli, including aac(3)-IIc, aac(6)-Ib and armA in Ouagadougou, and determined which antibiotics in this class are most affected by resistance. Material and Methods: This study was conducted on 216 E. coli strains collected from the biomedical analysis laboratories of Saint Camille and Schiphra hospitals. E. coli strains were isolated from pus and urine samples collected between September 2018 and January 2019. Antibiotic susceptibility testing was performed using aminoglycosides, β-lactams, fluoroquinolones, and sulfonamides. Aminoglycoside resistance genes were detected in strains with at least one aminoglycoside resistance gene using conventional/multiplex PCR. Results: Aminoglycoside resistance was observed in 46.8% (101/216) of strains. The resistance rates were respectively 45.37% for Tobramycin, 32.40% for Gentamicin, 14.81% for Kanamycin, 2.31% for Netilmicin, 1.84% for Neomycin, and 0.46% for Amikacin. PCR showed that 86 strains (85.15%) possessed the aac(3)-IIc gene, 71 strains or 70.30%) possessed the aac(6’)-Ib gene, and nine strains (8.91%) possessed the armA gene. Conclusion: Aminoglycoside resistance in pathogenic E. coli strains is mainly due to the presence of the aac(3’)-IIc and aac(6’)-Ib genes. The presence of armA was first reported in Burkina Faso. Netilmicin, Neomycin and Amikacin are good therapeutic options for treating urinary tract and pus-forming infections.

Amino terminus mutant OmpA from an isolated antibiotic resistant <i>Escherichia</i><i>coli</i>still possess resistance to environmental stresses

Antibiotic resistant Escherichia coli strains are becoming more common recently. OmpA is a very important antigen protein of E. coli, which consists of two separate domains, N-terminal and C-terminal domain. The N-terminal domain contains eight β- barrel regions that plays important roles in the multifaceted functions of OmpA. In the present study, we cloned a mutant OmpA gene from a multi-antibiotic resistant E. coli strain. Sequence analysis indicated that the N-terminal DNA sequence of the mutant OmpA shared 81.05% homology with the modeled OmpA from E. coli K12 and the N-terminal amino acid sequence of the mutant OmpA was 81.22% identical to that of the E. coli K12 OmpA. Moreover, several amino acids located in the β-barrel region were mutated. The mutant OmpA was expressed in BL21 suggested by SDS-PAGE. Resistance to environmental stress assay indicated that the N-terminus mutant OmpA still possessed excellent activities in pH, temperature and osmotic pressure resistance. Our pre- sent study may supply insights into better and deeper understand the relationships between OmpA N-terminal regions and its functions in environmental stress conditions and the mechanisms on antibiotic resistance of E. coli.

Linear Thanatin Is an Effective Antimicrobial Peptide against Colistin-Resistant <i>Escherichia coli in Vitro</i>

Colistin has been regarded as the last line antibiotic for treatment of infections caused by multidrug resistant gram-negative bacteria. Therefore, the increasing emergence of colistin resistance among gram-negative bacteria represents a serious problem. The objective of this study was to characterize the effectiveness of the chemically synthesized thanatin in linear form against colistin-resistant E. coli isolated from a pig farm in China. Agar diffusion assay and broth microdilution test were employed to analyze the susceptibility of colistin-sensitive E. coli (ATCC25922) and colistin-resistant E. coli (SHP45) to linear thanatin (L-thanatin). Combinatory effect of linear thanatin and colistin against E. coli was also determined by fractional inhibition concentration index (FICI) analysis. The results showed that L-thanatin at a concentration of 1 mg/ml produced larger inhibition zone on agar against ATCC25922 than SHP45. In the quantitative microdilution test, L-thanatin had the same MIC of 3.2 μg/ml for ATCC25922 and SHP45. Based on the FICI analysis, additive effect was obtained with 1.56 μg/ml of L-thanatin and 0.125 μg/ml of colistin for ATCC25922;but with 1.56 μg/ml of L-thanatin and 0.25 μg/ml of colistin or with 2 μg/ml of colistin and 0.39 μg/ml of L-thanatin for SHP45. These data proved that L-thanatin is an effective antimicrobial peptide against colistin-resistant E. coli.

Diarrheic Escherichia coli: A Predominant Etiological Agent of Gastroenteritis, a Case Study in Douala, Cameroon

Context: Gastroenteritis remains an infectious disease with high morbidity and mortality particularly in low incomes countries, where the capacity to search all etiological agents, especially pathogenic Escherichia coli, is very limited. We investigated the contribution of pathogenic Escherichia coli and their antibiotic resistance profiles in cases of gastroenteritis. Methods: A cross-sectional study was carried out on human stool samples from October 2021 to June 2022 at Laquintinie Hospital. Samples were received from patients of all age groups and screened for bacteriological and parasitological identification by microscopy, bacterial culture, biochemical identification, and antimicrobial susceptibility tests. Results: A total of 296 patients with gastroenteritis complaints, were enrolled in the study with ages ranging from 5 months to 90 years old (Median = 35.5;SD = 20.8). Among the samples analyzed, 1.7% (n = 5/296) were positive for parasites and 27% (n = 80/296) were positive for bacterial pathogens. Parasites were found in mono parasitism, mainly Entamoeba histolytica (60%;n = 3/5), followed by Trichomonas intestinalis (20%;n = 1/5), and Giardia intestinalis (20%;n = 1/5). Three species of bacterial pathogens were identified with no co-infection: diarrheic Escherichia coli (DEC), Salmonella sp, and Shigella sp with respective proportions of 90% (n = 72/80), 6.3% (n = 5/80), and 3.7% (n = 3/80). For antibiotic resistance profiles (ARPs) of the 72 isolates of DEC, high levels of resistance were observed globally with amoxicillin (93.1%;n = 67/72), followed by ciprofloxacin (75%;n = 54/72), and to trimethoprim + sulfamethazole (73.6%;n = 53/72). In contrast, DEC showed low resistance rates with nitrofurans (6.9%;n = 5/72) and imipenem (2.8%;n = 2/72). The strains had 56 distinct ARPs, of which 88.9% (n = 64/72) were MDR. Salmonella sp and Shigella sp showed high levels of resistance to amoxicillin and trimethoprim + sulfamethazole. Conclusion: These results emphasize the need to consider DEC as the main cause of consultation in cases of gastroenteritis and reiterate the urgent need to rationalize antibiotic use in Cameroon.

Prevalence of multi-drug resistant uropathogenic Escherichia coli in Potohar region of Pakistan

Objective:To scrutinize patterns of multi-drug-resistant uropathogenic Escherichia coli(UPEC) strains and particularly of fluoroquinolone-resistance this is an alternative choice for the treatment of urinary tract infections.Methods:Bacterial samples(n = 250) were collected from out-patients from August 2012 to August 2014 Islamabad.Antibiotic susceptibility profiling and determination of minimum inhibitory concentrations(MICs) and minimum bactericidal concentrations were performed according to the guidelines of Clinical and Laboratory Standards Institute(CLSI,2012).Genes,qnrA,qnrB and qnrS were identified by DNA amplification and sequencing.Results:The highest percentage of UPEC isolates were resistant to co-trimoxazole(82%) followed by cephalothin(80%),2nd Gen,3rd Gen and 4th Gen cephalosporins,respectively.Resistance against gentamicin,amikacin remained 29% and 4%.For other drugs including nitrofurantoin,tetracycline,carbapenem and beta-lactam inhibitors remained below 10%.Altogether,59% of the isolates were resistant to at least three antibiotics including one fluoroquinolone.Overall,MICs for ciprofloxacin remained(MIC≥256 μg/mL) and for levofloxacin(MIC≥16 μg/mL and 32 μg/mL).No significant differences were observed regarding MIC values of extended spectrumβ-lactamase(ESBL) and non-ESBL producers.For qnrS and qnrB positive isolates MICs remained above 32 μg/mL.Prevalence of UPEC was significantly higher among females and 40% of the isolates were ESBL producers.Conclusions:Higher percentages of ESBL producing UPEC were associated with urinary tract infections.Moreover,the majority of these isolates were multi-drug resistant and fluoroquinolone-resistant.

Efficacy of Some Antibiotics in Curing Resistant <i>Escherichia coli</i>Infection

There is growing interest in re-evaluation of older antibiotics with the wide spread of pathogen resistance, especially gram negative bacteria, which impair treatment of some infections. In contrast various studies have reported that some antibiotics have efficacy in clearing resistant bacterial infections. On account of that it was interesting to evaluate the efficacy of erythromycin, chloramphenicol and/or tenoxicam in curing and/or relieving wound infection of highly resistant Escherichia coli and investigate the possible mechanisms beyond their antibacterial activity. This was achieved through evaluating highly resistant E. coli strains in vitro using agar dilution and in vivo rat models of E. coli infected wound and acute inflammation by carrageenin, where possible mechanisms were evaluated through measuring immunological mediators and histopathological examination. This study revealed that in vivo, erythromycin alone or in combination with tenoxicam significantly improved the healing of infected skin wounds with E. coli irresspective of resistancy in vitro. In addition to the improvement of immunological mediators involved in inflammatory reaction, oxidative stress and in cytokines expression as response to the bacterial infection in vivo. On the other hand chloramphenicol neither alone nor in combination with tenoxicam, achieved any significant effect. Tenoxicam didn’t show antimicrobial activity alone nor in combination with tested antibiotics in vitro, but it has shown synergestic activity in combination with tested antibiotics in vivo. Thus we concluded that immunomodulatory activity of erythromycin through anti-inflammatory and antioxidant effects was the possible mechanisms by which this antibiotic had healed infection with resistant E. coli in vivo, despite its resistancy to this antibiotic in vitro.

Clonal Dissemination of Genetically Diverse Fluoroquinolone-Resistant Extended-Spectrum Beta-Lactamase (ESBL)-Producing Escherichia coli ST131 in a Veterans Hospital in Southern Taiwan

Uropathogenic Escherichia coli is the common pathogen to cause urinary tract infections (UTIs) and have become multidrug-resistant (MDR) extended-spectrum β-lactamase (ESBL) producers. The differences in the antimicrobial susceptibility, 5 bla genes, 12 virulence genes of 87 clinical ESBL-producing E. coli isolates and genomic variations and sequence types of 18 recurrent and repeated isolates from 9 patients were investigated. The 87 MDR-ESBL isolates collected mainly from indwelling urinary catheters (IUCs) and UTIs were highly resistant to fluoroquinolones, with over 50% of the isolates being resistant to cefepime and piperacillin/tazobactam and a few being resistant to carbapenem. These isolates carried at least two of the five bla genes examined, with the highest prevalence (87.4%) found for blaCTX-M (blaCTX-M3-like and blaCTX-M14-like), followed by blaCMY-2 (80.5%) and blaSHV (56.3%). The predominant virulence genes were the fimbriae gene fimH and the toxin genes cnf1 and hlyA in blood isolates and the capsule gene kpsMTII in UTI and blood isolates. Over 80% of the isolates carried yersiniabactin and aerobactin of siderophores. In 18 isolates, the fluoroquinolone-resistant ST131 isolate of pulsotypes I and II with blaCTX-M-15 was clonally disseminated in the hospital. The genomic plasticity of these ST131 occurred mainly through the conjugative plasmids with differences in replicon types A/C, I1, FIA, FIB and Y, size and number. In conclusion, MDR ESBL-producing E. coli isolates differed in virulence genes of UPEC and antibiotic resistance associated with the sources. Plasmid acquisition and chromosomal variations increase the spread of fluoroquinolone-resistant UPEC ST131 worldwide.

Multidrug Drug Resistance of Escherichia coli and Klebsiella Isolated from Iraqi Patients and Microbiota

Introduction: Escherichia coli and Klebsiella are Gram-negative bacilli of Enterobacteriaceae and are components of the colonic microbiota of animals and humans. The virulent strains cause gastroenteritis and urinary tract infections (UTI), and the incidence of the infections increases due to the increase of multidrug-resistant strains. The aim of this study is to determine the antibiotics resistance profile of E. coli and Klebsiella. Methodology: A total of 100 isolates of E. coli and Klebsiella were isolated from three sources, healthy stools and patient stools with gastroenteritis and urine subjects with UTI, during the period from November 2021 to January 2022. An antimicrobial susceptibility test was conducted with 14 antibiotics using the disc-Kirby-Bauer’s diffusion method. Results: Both E. coli and Klebsiella had variable abilities to resist the studied antimicrobial drugs, including 14 antibiotics belonging to nine different classes that have different patterns or mechanisms in stopping the growth or killing of microorganisms. All bacterial isolates revealed highly significant antimicrobial resistance almost for all antibiotics except carbapenems. About 72% of total isolates were multidrug-resistant (MDR), because they appeared resistant to at least three classes of antibiotics. Only two E. coli isolates out of 24 isolates (8.3%) were recovered from healthy stool samples and 6.25% of E. coli isolates (2 isolates out of 32) which were obtained from urine samples were sensitive to all antibiotics. The highest rates of antibiotic resistance were observed in E. coli than in Klebsiella. Both species had resistance to Amoxicillin-clavulanate (70.58%), Cefotaxime (58.96%), and Ceftazidime (57.81%). While the lowest frequency was meropenem (4.86%), and all strains were sensitive to imipenem (100%). Conclusion: These results partly explain the high prevalence of antibiotic resistance observed in Iraq due to drug misuse. Most of the bacterial strains were multidrug-resistant, and they spread more in pathogenic strains than in commensal strains.

多黏菌素E雾化吸入联合头孢哌酮钠舒巴坦钠治疗多重耐药革兰阴性菌感染所致肺炎患者的效果

目的:观察多黏菌素E雾化吸入联合头孢哌酮钠舒巴坦钠治疗多重耐药革兰阴性菌感染所致肺炎患者的效果。方法:回顾性分析2021年5月至2023年10月该院收治的96例多重耐药革兰阴性菌感染所致肺炎患者的临床资料,依据治疗方案不同将其分为研究组与对照组各48例。对照组采用头孢哌酮钠舒巴坦钠治疗,研究组在对照组基础上采用多黏菌素E雾化吸入治疗。比较两组临床疗效、临床症状(肺部阴影消失、细菌清除、体温复常)改善时间,治疗前后血气分析指标[动脉血氧分压(PaO_(2))、动脉血氧饱和度(SaO_(2))、动脉血二氧化碳分压(PaCO_(2))]、血清炎性指标[降钙素原(PCT)、白细胞介素-6(IL-6)、T细胞免疫球蛋白黏蛋白-4(TIM-4)、C反应蛋白(CRP)]水平,以及不良反应发生率。结果:研究组治疗总有效率为93.75%,高于对照组的79.17%,差异有统计学意义(P<0.05);研究组肺部阴影消失时间、细菌清除时间、体温复常时间均短于对照组,差异有统计学意义(P<0.05);两组PaO_(2)、SaO_(2)水平均高于治疗前,且研究组高于对照组,两组PaCO_(2)水平均低于治疗前,且研究组低于对照组,差异有统计学意义(P<0.05);两组PCT、IL-6、TIM-4、CRP水平均低于治疗前,且研究组低于对照组,差异有统计学意义(P<0.05);两组不良反应发生率比较,差异无统计学意义(P>0.05)。结论:多黏菌素E雾化吸入联合头孢哌酮钠舒巴坦钠治疗多重耐药革兰阴性菌感染所致肺炎患者可提高治疗总有效率,缩短临床症状改善时间,改善血气分析指标水平,以及降低血清炎性指标水平的效果优于单纯头孢哌酮钠舒巴坦钠治疗。