Detection of Drug Resistance in Escherichia coli Isolated from Animals and ERIC Analysis of Multidrug-resistant Strains

The drug resistance of Escherichia coli from animals was detected in Shandong Province in 2016,the gene mapping of Enterobacterial Repetitive Intergenic Consensus-PCR (ERIC-PCR) of multidrug-resistant isolates were analyzed,and then the relationship between ERIC-PCR genotyping and drug resistance of highly-resistant E.coli with multidrug resistance was discussed.A total of 110 E.coli isolates were separated and identified from diseased swine and avian,and their resistance to 10 kinds of antimicrobials was determined by the agar dilution method.Twenty highly-resistant isolates with multidrug resistance were selected to carry on the ERIC-PCR,followed by cluster genetic analysis according to the DNA fingerprints.The swine-sourced E.coli isolates possessed serious resistance against several kinds of antimicrobial agents,for example,all isolates were tolerant to florfenicol,doxycycline and ampicillin (100%),but had a relative lower resistance rate to cefotaxime sodium (57.14%).The same situation was observed in the poultry-sourced E.coli isolates,which had a resistance rate of 95.51% against florfenicol,while the lowest rate of 61.80% appeared on ciprofloxacin.Analysis of ERTIC showed dispersive fingerprint patterns of highly-resistant and multidrug- resistant isolates which represented a multiple clone resources,and there were certain correlation between the B genotype and the drug-resistant characteristics.It indicated that the animal-sourced E.coli isolates had a high level of drug resistance and were multidrug-resistant,which meant there was severe antibiotic resistance against not only different kinds of antibiotics but also different drugs of the same kind.The highly-resistant E.coli isolates with multidrug resistance had no apparent species preference,while their spread and pervasion posed a potential threat to the development of animal husbandry and the public health security.

Isolation and Identification of Drug-resistant Escherichia coli Strains from Chickens

[Objective] This study aimed to isolate and identify the drug-resistant Es- cherichia coli strains from chickens. [Method] E. coli strains were isolated from the fecal samples collected from five chicken farms around Shangqiu City, and verified by biochemical and pathogenic assay. [Result] Among the 35 isolated E. coli stains, 11 E. coil stains were sensitive to florfenicol, amikacin, neomycin and gentamicin; 12 E. coli stains were moderately sensitive to ciprofloxacin, doxycycline and norfloxacin; 15 E. coil stains were resistant against erythromycin, penicillin and streptomycin. [Conclusion] Strengthening biosecurity measures, rationally using vaccine and choosing effective antibiotics are the most cost-efficient methods to control E. coli.

Selection of Phage-resistant Strains from Escherichia coli glyA Genetic Engineering Bacteria

[ Objective] This study aimed to select E. coli strains with phage-resistance. [ Method] Phage-resistant strains of E. coli glyA genetic engineering bacteria were selected by phage induction and UV-coupling phage induction. [ Result] By phage induction, 20 strains with stable resistance were selected from the 24 phage-resistant strains, only one strain showed better growth condition than the original strains, but the enzymatic activities of the 20 strains were all lower than the original strains; 41 phage-resistant strains were selected by UV-coupling phage induction, 39 strains of which had better stability, including 7 strains that showed better growth conditions than the original strains and two strains had higher enzymatic activities than the original strains. [ Conclusion] UV-coupling phage induction is a suitable method to select phage-resistant strains from Ecoli genetic engineering bacteria.

Antimicrobial Drug Resistance Pattern of <i>Escherichia coli</i>Isolated from Chickens Farms with Colibacillosis Infection

Colibacillosis refers to any localized or systemic infection caused entirely or partly by avian pathogenic Escherichia coli (APEC). Colibacillosis in mammals is most often a primary enteric or urinary tract disease, whereas colibacillosis in poultry is typically a localized or systemic disease occurring secondarily when host defenses have been impaired or overwhelmed by virulent E. coli strains. The purpose of this study was to investigate the antimicrobial drug resistance pattern of Escherichia coli isolated from broiler chickens farms with colibacillosis infection. Dead birds from commercial broiler chicken farms showing signs of colibacillosis were necropsied and swab samples were collected from internal organs and blood aseptically for the isolation of Escherichia coli. Pure colonies of the bacteria were isolated on solid media and the isolates were identified as E. coli based on morphological and biochemical characteristics. For determination of susceptibility to antibacterial agents, the disc diffusion method on Muller-Hinton agar was used. The following antimicrobial agents were tested: gentamycin, oxytetracyline, colistin, ciprofloxacin, doxycycline, nalidixic acid, co-trimoxazole (trimethoprim-sulfamethoxazole), norefloxacin, lincospectin and cefuroxime. The drug resistance patterns of the organisms were determined as a percentage and reported at three levels: susceptible, intermediate and resistant. All the isolates of Escherichia coli showed resistance to several antibiotics and a pattern of multiple drug resistance was observed. The highest rate of resistance was observed against nalidixic acid (100%) and the least rate of resistance was observed against gentamycin (17%). According to the results of this research care must be taken to avoid secondary infection (colibacillosis) in chicken farms and also avoid in careless antimicrobial consumption in food animals including chickens.

Comparison of extended spectrum β-lactamasesproducing Escherichia coli with non-ESBLsproducing E.coli:drug-resistance and virulence

The virulent factors of Escherichia coil （E.cofi） play an important role in the process of pathopoiesis. The study aimed to compare drug-resistant genes and virulence genes between extended spectrum β-1actamases （ESBLs）-producing E.coli and non-ESBLs-producing E.cofi to provide a reference for physicians in management of hospital infection. From October 2010 to August 2011,96 drug-resistant strains of E. coli isolated were collected from the specimens in Qingdao Municipal Hospital, Qingdao, China. These bacteria strains were divided into a ESBLs-producing group and a non-ESBLs-producing group. Drug sensitivity tests were performed using the Kirby-Bauer （K-B） method. Disinfectant gene, qacEAl-sull and 8 virulence genes （CNF2, hlyA, eaeA, VT1, est, bfpA, elt, and CNF1） were tested by polymerase chain reaction （PCR）. Among the 96 E.coli isolates, the ESBLs-producing E.coli comprised 46 （47.9%） strains and the non-ESBLs-producing E.cofi consisted of 50 （52.1%） strains. The detection rates of multiple drug-resistant strain, qacEAl-sull, CNF2, hlyA, eaeA,VT1, est, bfpA, elt, and CNF1 in 46 ESBLs-producing E.coli isolates were 89.1%, 76.1%, 6.5%, 69.6%, 69.6%, 89.1%, 10.9%, 26.1%, 8.7%, and 19.6%, respectively. In the non-ESBLs-producing E.cofi strains, the positive rates of multiple drug-resistant strain, qacEAl-sull, CNF2, hlyA, eaeA, VT1, est, bfpA, elt, and CNF1 were 62.0%, 80.0%, 16.0%, 28.0%, 64.0%, 38.0%, 6.0%, 34.0%, 10.0%, and 24.0%, respectively. The difference in the detection rates of multiple drug-resistant strain, hlyA and VT1 between the ESBLs-producing E.cofi strains and the non-ESBLs-producing E.cofi strains was statistically significant （P〈0.05）. The positive rate of multiple drug-resistant strains is higher in the ESBLs-producing strains than in the non-ESBLs-producing strains. The expression of some virulence genes hlyA and VT1 varies between the ESBLs-producing strains and the non-ESBLs-producing strains. Increased awareness of clinicians and enhanced testing by laboratories are required to reduce treatment failures and prevent the spread of multiple drug-resistant strains.

Analysis of the Drug Sensitivity of Escherichia coli Isolated from Sheep in Yangling,Shaanxi Province

This study was conducted to investigate the drug sensitivity of Escherichia coli isolated from sheep, providing data reference for clinical medication. Fifty-four samples were collected from a certain sheep farm in Yangling, Shaanxi Province for E. coli isolation and identification, and K-B disk diffusion method was used to carry out the dug sensitivity test of 40 E. coli to the eight antimicrobials of spectinomycin, amikacin, tobramycin, enrofloxacin, nalidixic acid, levofloxacin, salafloxacin and ciprofloxacin. The results showed that there were 40 positive E. coli strains and the isolation rate was 74.7%. The resistance rates of the 40 E. coli to spectinomycin, amikacin,tobramycin and nalidixic acid were 85%, 95%, 97.5% and 87.5%, respectively, while the resistance rate to enrofloxacin, levofloxacin, salafloxacin and ciprofloxacin were relatively low and the resistance rates were 35%, 20%, 25% and 17.5%, respectively. The isolates showed different levels of drug resistance to eight antimicrobials and the highest resistance rate was 97.5%. It reminds that the sheep farm should strictly control the dosage according to the antimicrobial sensitive data in clinic.

Multi-Drug Resistance Pattern of Lactose Non-Fermenting <i>Escherichia coli</i>as Causative Agent of Urine Tract Infections in Luanda, Angola

This prospective study was carried out to assess the sensitivity and resistance pattern of lactose non-fermenting Escherichia coli from July 2018 to December 2018 in the Laboratory of Microbiology at Luanda Medical Center, Angola. Out of 1170 patient, a total of 120 urine specimens infected with Escherichia coli (>105 CFU/ml) were collected according to the routine protocol of urinalysis. Among these 120 isolates, 25 (21%) isolates were determined as “atypical”, lactose non-fermenting E. colis trains. The twenty-five lactose non-fermenting Escherichia coli strains isolated from urine samples in Luanda Medical Center were declared as Multiple Drugs-Resistant strains with high resistance to Cefalexine (100%), Cefuroxime (100%), Ceftriaxone (92%), Gentamycin (92%), Ciprofloxacin (72%) and Amoxiciclin/Clavulanic (80%). The alarming resistance level to the first-choice drugs for the treatment of urinary tract infections caused by non-fermentative lactose E. coli was observed.

Monitoring and Analysis on Multi Drug Resistance of Escherichia coli from Captive Population Amur Tiger

In order to investigate the multi drug resistance to Escherichia coli from captive population Amur tiger,E. coli strains were isolated from the fecal samples of tiger in Heilongjiang Amur Tiger Park in Harbin. The sensitivity of E. coli isolates to 14 antibiotics was determined by scrip diffusion method. The results indicated that all the isolates varied in drug resistance to different antibiotics; the isolates gave high resistance to ampicillin,with a drug fast rate of 100%; over80% of the isolates were resistant to tetracycline and Paediatric Compound Sulfamethoxazole Tablets(SMZ- TMP),and over 70% of the isolates were sensitive to aztreonam,amoxicillin /potassium clavulanate. Most of the isolates had high sensitive to aztreonam and amoxicillin / clavulanate acid.

Prevalence,serotyping and drug susceptibility patterns of Escherichia coli isolates from kidney transplanted patients with urinary tract infections

BACKGROUND Extended-spectrumβ-lactamase(ESBL)-producing Escherichia coli(E.coli)are among the main pathogens in urinary tract infections(UTIs)among kidney transplant patients(KTPs).AIM To estimate the prevalence of ESBL-producing E.coli in KTPs and to evaluate the most prevalent serotypes and antibacterial susceptibility patterns of isolated bacteria in Tehran,Iran.METHODS A total of 60 clinical isolates of uropathogenic E.coli were collected from 3 kidney transplant centers from April to May 2019.Antimicrobial susceptibility testing was performed by the disk diffusion method as recommended by the Clinical Laboratory and Standards Institute.The serotyping of E.coli isolates was performed by the slide agglutination method.The presence of blaTEM,blaSHV,and bla CTX-M genes was evaluated by polymerase chain reaction.RESULTS The frequency of ESBL-producing E.coli in KTPs was found to be 33.4%.All of the 60 E.coli isolates were found to be susceptible to doripenem(100%)and ertapenem(100%).High resistance rates to ampicillin(86%),cefotaxime(80%),and cefazolin(77%)were also documented.The most frequent serotypes were serotype I(50%),serotype II(15%),serotype III(25%),and serotype VI(10%).The gene most frequently found was blaTEM(55%),followed by blaCTX-M(51%)and blaSHV(41%).CONCLUSION Molecular analysis showed that blaTEM was the most common ESBL-encoding gene.The high resistance toβ-lactams antibiotics(i.e.,ampicillin,cefotaxime,and cefazolin)found in E.coli from KTPs with UTIs remains a serious clinical challenge.Further efforts to control ESBL-producing E.coli should include the careful use of all antibiotics as well as barrier precautions to reduce spread.

Study on the Resistance of Pathogenic Escherichia coli to Ceftiofur

[Objective] Ceftiofur was as the substrate to induce the standard strain of Escherichia coli（E.coli）to be the drug-resistance one.The resistant mechanism of E.coli to ceftiofur was studied.[Method] The sub-inhibitory concentration method was used to induce the standard strains C83907 and C83845.After they were induced for 10 generations,the double disc synergy test（DDST）,NCCLS（National Committee for Clinical Laboratory Standards）confirmatory test and PCR amplification were used to detect the extend spectrum β-lactamases（ESBLs）.The two fold dilution method was used to measure the minimal inhibitory concentration（MIC）of cetiofur to the strain which produced ESBLs.For the drug-resistance strain which produced ESBLs,the two fold dilution method was used to measure the minimal inhibitory concentrations of different proportions of cetiofur and tazobactam sodium.[Result] After they were induced 15 generations,MIC value of ceftiofur to the induced bacteria was during 8-10 μg/ml,and ESBLs was detected.MICs of cetiofur combining tazobactam sodium（the mass ratio was 1∶1-8∶1）to Escherichia coli produced ESBLs reduced 20-22 times than that of cetiofur.[Conclusion] The main mechanism of pathogenic Escherichia coli resistance to ceftiofur was that which produced ESBLs.

In vitro biofilm formation by uropathogenic Escherichia coli and their antimicrobial susceptibility pattern

Objective:To detect in vitro biofilm formation of uropathogenic Escherichia coli(E.coli)(UPEC) strains isolated from urine specimens and also to determine their antimicrobial susceptibility pattern using 13 commonly used antibiotics.Methods:The present study comprised of 166 urine specimens collected from tertiary care hospitals in and around Coimbatore.South India. All the specimens were subjected to gram staining,bacterial culture and the E.coli strains were screened for biofilm formation using Tube Method(TM),Congo Red Agar(CRA) and Tissue Culture Plate method(TCP) respectively.Subsequently,the antimicrobial susceptibility test was performed by Kirby Bauer-disk diffusion method for the biofilm and non-biofilm producing E. coli strains.Results:Of the 100(60.2%) E.coli strains,72 strains displayed a biofilm positive phenotype under the optimized conditions in the Tube Method and the strains were classified as highly positive(17,23.6%),moderate positive(19.26.3%) and weakly positive(36.50.0%). similarly under the optimized conditions on Congo Red agar medium,biofilm positive phenotype strains were classified as highly positive(23,23%).moderate positive(37.37%) and weakly positive(40,40%).While in TCP method,the biofilm positive phenotype strains were also classified as highly positive(6.6%),moderate positive(80.80%) and weakly positive(14,14%),it didn’t not correlate well with the tube method for detecting biofilm formation in E.coli.The rates of antibiotic resistance of biofilm producing E.coli were found to be 100%for chloramphenicol and amoxyclav(amoxicillin and clavulanic acid),86%for gentamicin and cefotaxime.84%for ceftazidime,83%for cotrimoxazole and piperacillin/tazobactam,75%for tetracycline and 70% for amikacin,Conclusions:This study reveals the prevalence and antimicrobial susceptibility pattern of biofilm and non-biofilm producing uropathogenic E.coli strains.

Antiboitic Resistance of Uropathogenic Eshcherichia coli in Pateints of Hargeisa Group Hospital, Hargeisa, Somaliand

Background: Urinary tract infection is a common disease in Somaliland society. The predominant causative organism of Urinary tract infection is Escherichia coli. This research studies antibiotic resistance of uropathogenic E. coli in patients of Hargeisa Group Hospital. The study selected commonly prescribed antibiotics for urinary tract infection treatment. Methodology: Urine samples of patients were cultured to isolate causative organisms of the urinary tract infection. Chromo-agar media, CLED, and biochemical tests are applied to identify the type of bacteria. Antibiotic reactions to E. coli bacteria are measured to differentiate between sensitive and resistant drugs with the guidance of the Clinical and Laboratories Standard Institute (CLSI). Kirby Bauer disc diffusion method is applied to assess antimicrobial activity against E. coli. Data of patients such as age, sex, symptoms of UTI, previous UTI infection, and history of antibiotic use were recorded. SPSS and Microsoft Excel are applied to analyze and interpret data. Results: The predominant organism that caused urinary tract infection was Escherichia coli (55%), Klebsiella spp (15%), Candida spp (15%), Enterococcus spp (10%), Staph spp 2.5%, and Pseudomonas spp 2.5% while other 55% were negative. The study assessed antibiotic resistance of E. coli, which reported resistance to Tetracycline at (70%), Ampicillin (64%), and Cotrimoxazole (61%). The bacteria showed moderate resistance to Ceftriaxone (43.5%), Nalidixic acid (43%), and Ciprofloxacin (36%). The bacteria are sensitive to Amikacin (100%), Nitrofurantoin (96%), Levofloxacin (73%) and gentamicin (74%). Conclusion: The overall incidence of antibiotic resistance to E. coli is high because the bacteria show a percentage of resistance to each antibiotic except Amikacin which gives (100%) sensitivity. The research recommends public awareness of the risks associated with antibiotic use and periodic evaluation of antibiotic resistance to accomplish better managing urinary tract infections.

“黄金洗剂”逆转ESBLs+E.coli耐药性的体外实验研究

目的探讨中药“黄金洗剂”对产超广谱β-内酰胺酶的大肠埃希菌(ESBLs+E.coli)的体外抗菌效果及其逆转细菌耐药的部分机制。方法通过肉汤稀释培养法确定“黄金洗剂”对ESBLs+E.coli的最低抑菌浓度(MIC),然后应用改良Kirby-Bailer法分析“黄金洗剂”对ESBLs+E.coli耐药性的逆转效果,最后通过结晶紫染色分析生物膜形成能力和检测ESBLs酶活性来探讨“黄金洗剂”逆转细菌耐药的机制。结果“黄金洗剂”对ESBLs+E.coli的MIC为0.6 g/mL,其最佳抑菌条件是0.5 g/mL的药物浓度作用细菌24 h。此时“黄金洗剂”能够逆转细菌对第四代头孢菌素头孢吡肟的耐药性[(13.9±1.2)%],而对第三代头孢菌素头孢噻肟和头孢曲松的逆转率很低。进一步研究发现“黄金洗剂”能够逆转细菌耐药是因为该中药能够抑制生物膜形成,抑制ESBLs酶活性。结论“黄金洗剂”在0.5 g/mL条件下作用细菌24 h能够明显逆转细菌对头孢吡肟的耐药性,主要通过抑制细菌生物膜的形成和ESBLs的酶活性来实现。

鬼针草血清与抗菌药联合对耐药E.coli体外抑菌的研究

为了探讨鬼针草血清与抗菌药联合诱导细菌传代的体外抑菌活性,试验制备了鬼针草含药血清,采用二倍微量稀释法体外检测鬼针草血清与抗菌药联合诱导耐药大肠杆菌的抑菌传代情况。结果表明:鬼针草血清与抗菌药联合诱导细菌传代对耐药大肠杆菌有不同程度的抑菌活性。说明鬼针草血清可明显增强β-内酰胺类、氨基糖苷类和酰胺醇类抗菌药对耐药菌的抑制作用。

秦皇岛地区貂源大肠杆菌(E. coli)的分离鉴定及药敏试验分析

为了确定秦皇岛地区貂源大肠杆菌(E. coli)流行情况及耐药性。本试验从秦皇岛地区不同水貂养殖场采集腹泻水貂的肠内容物及粪便57份,通过细菌的分离培养,形态学观察、生化鉴定等方法,分离鉴定出42株E.coli。致病性试验表明,34株为致病性E.coli。药敏试验结果表明,该菌仅对头孢克肟、头孢曲松、氟苯尼考等4种药物高度敏感;该菌具有很强的耐药性,耐药率达到40.4%～100%;该菌存在多重耐药现象,最高耐15种药物,且均耐8种药物以上。本研究为该地区水貂大肠杆菌病防治提供研究基础。

Multi-drug Resistant Uropathogenic Escherichia coli and Its Treatment by Chinese Medicine

Objectives： To investigate the resistance and virulence profiles of uropathogenic Escherichia coli（UPEC） and its treatment by Chinese medicine（CM） Fuzheng Qingre Lishi Formula（扶正清热利湿方, FQLF）. Methods： UPEC strains were isolated from recurrent urinary tract infections（UTIs） patients. Patient sensitivities to 17 antibiotics were tested by the disk diffusion method. Virulence genes were screened by plolymerase chain reaction. A mouse model was constructed using a multi-drug resistant and virulent UPEC strain and treated with FQLF or the antibiotic imipenem. The treatment efficacy was evaluated by bacterial clearance from urine and the urinary organs. Results： A total of 90 UPEC strains were collected, and 94.4% of the isolates were resistant to at least 1 antibiotic. Approximately 66.7% of the UPEC strains were multi-drug resistant. More than one virulence gene was found in 85.6% of the isolates. The extended-spectrum β-lactamases（ESBL）-positive strains were more resistant than the negative ones. The virulence gene number was positively correlated with the resistance number（P〈0.05）. A mouse model was successful y constructed using UPEC10. Treatment with either FQLF or antibiotics significantly cleared bacteria from the mouse urine after 14 days. In the untreated control, the bacteria lasted for 28 days. FQLF treatment of the UTI mouse model greatly reduced the bacterial number in the kidney and bladder, but could not completely clear the bacteria. Conclusions： Multi-drug resistance is common among UPEC isolates, and the resistance is positively related with virulence. FQLF could treat UPEC UTIs, but could not completely clear the bacteria from the host.

一株多重耐药大肠杆菌全基因组测序及其耐药性分析

为了解大肠杆菌携带的粘菌素耐药基因并筛选敏感药物,解决多重耐药和动物临床无药可选的困局,采用16S rRNA菌种全基因组测序,PCR筛查mcr-4、mcr-5、blaTEM和AmpC酶耐药基因,应用BLAST和MEGA软件进行生物信息学和系统进化树分析,并对该菌株进行了78种抗生素抗菌药物敏感性测试及4种天然植物提取物(黄藤素、黄连素、黄芩苷和博落回)的抑菌、杀菌效果试验。结果表明,从2021年(1—12月)和2022年(1—6月)猪临床腹泻病例肠道中分离鉴定的145株大肠埃希菌(Escherichia coli,E.coli)中,鉴定出1株同时携带粘菌素耐药基因(mcr-4,mcr-5)和β内酰胺酶blaTEM、AmpC基因的猪源大肠埃希氏菌临床菌株HN2149。78种抗生素药敏试验结果显示,HN2149菌株对头孢吡肟、头孢地嗪、磷霉素、头孢克肟、头孢唑林、头孢哌酮、美洛培南、头孢西丁、头孢呋辛、头孢曲松、头孢噻肟、头孢他啶、替卡西林/克拉维酸、头孢哌酮/舒巴坦、氨曲南、哌拉西林/他唑巴坦、头孢噻肟/克拉维酸、头孢唑肟、头孢美唑、头孢他啶/克拉维酸和头孢他美敏感,对其余57种抗菌药物表现为耐药。4种植物提取物的药敏结果显示,博落回对菌株HN2149的抑菌、杀菌效果较好,其余3种提取物均对该菌株无抑菌和杀菌效果。以上研究结果为猪大肠杆菌病的防控提供参考。

某医院近10年大肠埃希菌分离率和耐药率的变迁情况

目的总结近10年中国医科大学附属第一医院大肠埃希菌的分离率和耐药率,为临床抗感染经验治疗提供依据。方法数据来自2013年至2022年间从中国医科大学附属第一医院就诊患者中分离的大肠埃希菌,使用VITEK 2和VITEK MS进行菌种鉴定,使用VITEK2和KB法进行药物敏感性试验,采用WHONET 5.6软件进行分析。结果2013年至2022年共分离6845株菌株,其中80.5%来自住院患者,19.5%来自门诊和急诊患者。常见标本类型为尿液(57.8%)、血液(15.0%)、分泌物(9.2%)、引流液(8.1%)。大肠埃希菌超广谱β-内酰胺酶(ESBL)分离率为57.2%(54.3%~61.5%)。大肠埃希菌对碳青霉烯类抗菌药物的耐药率较低,仅为1.2%(0.2%~2.6%)。结论大肠埃希菌仍是临床感染的重要病原菌,对多种抗菌药物存在不同程度的耐药,且耐药率有上升趋势,临床医师应给予足够的关注。

2015-2021年CHINET尿液分离菌分布和耐药性变迁

目的了解2015-2021年CHINET细菌耐药监测网中尿液分离菌的分布和耐药性。方法收集CHINET细菌耐药监测网51家医疗机构2015-2021年所有尿液标本临床分离菌的耐药监测数据资料,采用WHONET 5.6软件进行统计分析。结果2012-2021年尿液标本共分离细菌261893株,其中革兰阳性菌62219株,占23.8%,革兰阴性菌199674株占76.2%。常见的分离菌依次为大肠埃希菌(46.7%)、屎肠球菌(10.4%)、肺炎克雷伯菌(9.8%)、粪肠球菌(8.7%)、奇异变形杆菌(3.5%)、铜绿假单胞菌(3.4%)、无乳链球菌(2.6%)和阴沟肠杆菌(2.1%)。上述细菌主要分离自住院患者,女性多见于男性,成人多见于儿童。大肠埃希菌、肺炎克雷伯菌和奇异变形杆菌中产超广谱β内酰胺酶(ESBL)菌株分别占53.2%、52.8%和37.0%。耐碳青霉烯类的大肠埃希菌、肺炎克雷伯菌、铜绿假单胞菌和鲍曼不动杆菌中检出率分别为1.7%、18.5%、16.4%和40.3%。粪肠球菌对氨苄西林、呋喃妥因、利奈唑胺、万古霉素、替考拉宁和磷霉素的耐药率<10%,屎肠球菌对氨苄西林、左氧氟沙星、红霉素的耐药率>90%,对万古霉素、利奈唑胺和替考拉宁的耐药率<2%。ICU住院患者分离的大肠埃希菌、肺炎克雷伯菌、铜绿假单胞菌和鲍曼不动杆菌对大部分抗菌药物的耐药率明显高于门诊患者和非ICU住院患者。结论尿液标本临床分离菌主要以大肠埃希菌、肠球菌和肺炎克雷伯菌为主,不同人群尿液标本中分离的细菌种类和耐药性不尽相同,应重视细菌耐药监测,减少抗菌药物的不合理使用。

北京某医院感染性腹泻患者致泻性大肠埃希菌毒力和耐药特征分析

目的明确本院感染性腹泻患者致泻性大肠埃希菌毒力和耐药特征。方法采用VITEK MS微生物质谱检测系统初步鉴定,多重实时荧光PCR检测毒力基因,对本院感染性腹泻患者临床分离的致泻性大肠埃希菌(Diarrheagenic Escherichia coli,DEC)进行5种型别鉴定。微量肉汤稀释法和E-test法药敏试验检测DEC菌株的耐药表型特征。二代测序及生物信息学分析其耐药分子特征。采用Fisher确切概率法进行统计学分析。结果本院DEC检出率为11.9%,其中EAEC占比37.5%,非典型EPEC占比34.38%,ETEC占比25.0%,EIEC占比3.12%,未检出EHEC菌株。32株DEC对氨苄西林、四环素、甲氨苄啶/磺胺异恶唑耐药率最高,分别为53.12%、43.75%和37.5%。ESBLs(+)株占比18.75%,其多重耐药菌株检出率为83.83%,显著高于ESBLs(-)菌株,差异有统计学意义(P=0.042)。32株DEC共有25个ST型,优势基因型为ST10共4株(12.5%),ST28、ST31和ST3153各2株(各占比6.25%),其他21个型别各1株菌(各占比3.13%)。EAEC中检出1株携带bla_(NDM-1)的耐碳青霉烯类菌株。结论我院感染性腹泻患者的DEC以aggR、pic、astA、eae 4种毒力基因较为常见,以EAEC、EPEC为主要型别,基因型别呈高度多态性,检出多重耐药菌株。