新疆喀什地区腹泻羔羊源产ESBL大肠杆菌的耐药性和系统进化分群研究

目的了解新疆喀什地区腹泻羔羊源产ESBL大肠杆菌的流行情况及耐药性,指导临床大肠杆菌病的防治。方法采集385份喀什地区腹泻羔羊肛周粪便,分离得到371株大肠杆菌,通过双纸片协同法筛选产ESBL大肠杆菌,对筛选到的菌株进行耐药基因鉴定、耐药性分析和系统进化分群研究。结果371株大肠杆菌中204株为产ESBL菌株,bla CTX-M、bla CTX-M-1G、bla CTX-M-9G和bla TEM耐药基因携带率分别为67.65%、69.12%、30.39%和63.73%,产ESBL阳性菌株均为多重耐药,对氨苄西林、头孢噻肟、庆大霉素、恩诺沙星、阿奇霉素、四环素、氯霉素、甲氧苄啶、氨曲南8种药物的耐药率为90.69%~100%,系统进化分群主要分布于A群和D群,其中A群菌株以10重耐药为主(41.11%),D群菌株以11重耐药为主(40%)。结论产ESBL菌株大肠杆菌是引起喀什地区羔羊腹泻的主要病原菌,以A群为主,且均为多重耐药。

羊腹泻大肠杆菌整合子及ESBLs携带情况检测

为了确定内蒙古自治区羊腹泻大肠杆菌的耐药机制,本试验采用PCR方法检测呼和浩特市周边牧场分离菌株中整合酶基因(Ⅰ、Ⅱ、Ⅲ型)、耐药基因盒和编码超广谱β-内酰胺酶(ESBLs)基因的携带情况。结果显示,108株羊腹泻大肠杆菌中,Ⅰ型整合酶基因和耐药基因盒插入区扩增呈阳性的菌株为42株,检出率为38.9%,未检出Ⅱ、Ⅲ型整合酶基因;菌株中有5类基因盒流行,主要携带甲氧苄氨嘧啶(dfr)和氨基糖苷类(aadA)耐药基因;分离菌株的bla_(TEM)基因检出数为83株,占比76.9%,bla SHV和bla_(CTX)基因PCR扩增均为阴性;质粒DNA上成功扩增出携带bla TEM型ESBLs基因的Ⅰ型整合子阳性菌株40株。结果表明,内蒙古自治区羊腹泻大肠杆菌Ⅰ型整合子的携带率较高,菌株对磺胺类、甲氧苄氨嘧啶和氨基糖苷类药物的耐受性与其携带的耐药基因盒密切相关,分离菌株中ESBLs的产生和传播由菌株自身质粒所介导,这可能是其对β-内酰胺类抗菌药物耐药的主要原因,且Ⅰ型整合子在ESBLs阳性菌株中的广泛分布,也使得菌株携带的耐药基因更易散播。本试验通过对羊腹泻大肠杆菌耐药性的产生和传播进行分析,以指导临床合理用药。

梅花鹿源大肠杆菌ESBLs基因型检测与分析

为分析黑龙江省梅花鹿源产超广谱β-内酰胺类酶(ESBLs)大肠杆菌耐药基因的分布情况,为临床抗微生物药的合理使用提出指导意见。从黑龙江省4个养殖场中分离出130株梅花源大肠杆菌,采用K-B纸片法,结果显示对诺氟沙星、环丙沙星、氧氟沙星的耐药率达到10%以上。采用PCR技术对ESBLs基因进行检测。结果显示,耐药基因OXA、TEM的检出率分别为13.85%(18/130)、76.15%(99/130),CTX-M和SHV均未检出。4个养殖场的ESBLs基因以TEM为主。

Prevalence and Resistance Profile of Muenchen Cefotaximase (CTX-M) Group 1 Extended Spectrum Beta-Lactamase (ESBL)-Producing Uropathogenic Escherichia coli Strains in Dakar, Senegal

Background: Extended-spectrum beta-lactamase (ESBL) producing bacteria are a real public health problem, particularly in Africa. Among these ESBLs, there are the Muenchen Cefotaximase (CTX-M) described all over the world of which the most frequent is the CTX-M of group 1 particularly the CTX-M-15 variant. The objective of this study was to determine the prevalence of CTX-M group 1 ESBL-producing Escherichia coli strains and to test their antibiotics susceptibility profile. Methodology: A retrospective cross-sectional descriptive study was conducted to detect ESBL-secreting Escherichia coli strains by the synergy test. Identification of CTX-M type ESBL from group 1 was performed using the NG-Test CTX-M rapid diagnostic test (NG-Biotech®). Antibiotic susceptibility profile was determined using CA-SFM/EUCAST guidelines 2019. Data entry and statistical analysis were performed with Excel version 2010 and SPSS 20.0 respectively. Results: Eighty-two ESBL-producing Escherichia coli strains were tested. A group 1 CTX-M ESBL was detected in 75.6% of the strains (n = 62). These strains were highly resistant to cefotaxim (100%), aztreonam (100%), ceftazidim (85.4%) and cefepim (66.1%). They were also resistant to quinolones, gentamycin and sulfadoxine-trimethoprim combination. However, these strains showed sensitivity to ertapenem (100%), cefoxitin (69.3%), tigecyclin (66%), and amikacin (66.1%). The combination of piperacillin and tazobactam was active on 30.6% of the strains against 6.4% for the combination of amoxicillin and clavulanic acid. Conclusion: The CTX-M type ESBL of group 1 was present in the majority of ESBL-producing Escherichia colis trains. Despite the production of this enzyme conferring resistance to most beta-lactam antibiotics, some antibiotics remain active to treat infections caused by these germs.

Phenotypic Characterization of Extended Spectrum Beta-Lactamase, Class C Cephalosporinase and Carbapenemase-Producing Klebsiella Species Isolated from Patients Consulted at Four Yaounde-Based Hospitals

Background: Klebsiella spp. are bacteria of medical importance for their role in opportunistic infections which are often difficult to treat because of resistance to one or several antimicrobials. The aim of this study was to determine antimicrobial resistance due to Extended Spectrum Beta-lactamase (ESBL), Class C cephalosporinase (AmpC) and carbapenemase enzymes in Klebsiella spp. isolated from patients consulted at four hospitals. Methodology: The study was cross-sectional and descriptive. A total of 4190 non-repetitive patients specimens from 13 types of clinical specimens were analysed from February to November 2020. Two hundred and twenty-five (225) Klebsiella spp isolates were identified using API 20E and antimicrobial susceptibility testing done according to the Kirby Bauer disc diffusion method. ESBL and AmpC phenotypes were determined by the combination disc method and carbapenemases by double disc synergy method, referenced by EUCAST guidelines for the resistance testing. Results: The frequency of the species was Klebsiella pneumoniae (69%, 155/255), K. oxytoca (14%, 31/255), K. ozaenae (12%, 27/225) and K. rhinoscleromatis (5%, 11/225). Isolates were most resistant to sulphomethoxazole trimethoprim (84%, 189/225), cepaholosporins (80%, 180/225), and least resistant to carbapenems (10.7%, 24/225). Two K. oxytoca and one K. pneumoniae were resistant to all antibiotics tested. Klebsiella pneumoniae had the most multidrug resistant isolates (59.4%, 134/225). Most isolates (83.6%, 188/225) expressed at least one enzyme, while 63.6% (143/225) of the isolates expressed at least two enzymes. Some isolates were ESBL (71.6%, 161/225), carbapenemase (10.7%, 24/225) and AmpC (6.6%, 15/225) producers. Three carbapenemases (Klebsiella pneumoniae carbapenemase-KPC, Metallo-Beta Lactamase-MBL and OXA-48) were detected. Conclusion: These results revealed that resistance of Klebsiella spp. to cephalosporins is high and this may be exacerbated by co-expression of AmpC and carbapenemases aggravating associated patient morbidity and mortality. Monitoring of antimicrobial resistance of local strains is necessary for informed decisions on empirical treatment. .

羔羊源产ESBLs与非产ESBLs大肠埃希氏菌耐药性差异比较及基因型分析

为了明确宁夏地区羔羊源大肠埃希氏菌产超广谱β-内酰胺酶(ESBLs)与非产ESBLs大肠埃希氏菌的耐药性差异和相关基因携带情况差异,对实验室分离保存的87株羔羊源大肠埃希氏菌,采用ESBLs表型检测方法筛选产ESBLs的菌株和K-B纸片法进行药物敏感性试验,采用PCR法对分离株进行相关基因的检测。结果显示,87株大肠埃希氏菌中5株为产ESBLs菌株,检出率为5.75%。产ESBLs株对多数试验药物呈耐药性;而非产ESBLs菌株对多数试验药物敏感,仅对恩诺沙星、复方新诺明和红霉素耐药率超过50%。20种药物中,产ESBLs株大肠埃希氏菌对18种药物的耐药率极显著高于非产ESBLs菌株(P<0.01)。产ESBLs菌株携带blaCTX的阳性率极显著高于非产ESBLs菌株(P<0.01),产ESBLs菌株中的blaTEM和blaOXA基因的阳性率均高于非产ESBLs菌株,但差异不显著(P>0.05)。结果表明宁夏地区羔羊源大肠埃希氏菌产ESBLs菌株流行率低,产ESBLs菌株耐药性严重,且宁夏地区羔羊源ESBLs菌株优势基因型为blaCTX和blaTEM。

肠杆菌科细菌耐药基因NDM和ESBLs的检测及白头翁汤增强其敏感性研究

采用美国临床实验室标准化协会(Clinical and Laboratory Standards Institute,CLSI)推荐的方法,检测了临床分离的44株肠杆菌科细菌产超广谱β-内酰胺酶(Extended-Spectrum Beta-Lactamases,ESBLs)的情况.利用PCR对临床分离菌进行新德里金属β-内酰胺酶(New Delhi metallo-β-lactamase,NDM)以及ESBLs耐药基因的检测.用微量肉汤稀释法测定了分离菌对阿莫西林等14种抗菌药的敏感性,并统计其耐药率.结果表明,临床分离的44株肠杆菌科细菌中,有31株产超广谱β-内酰胺酶,检出率为70.5%.耐药基因检测结果显示,耐药基因NDM-1携带率为13.6%.ESBLs耐药基因TEM,SHV,CTX-M,OXA的携带率分别为100%,43.2%,45.5%,6.8%.同时发现,有6株菌株同时检出了含NDM-1和ESBLs的基因,有9株菌株同时检出含有2种ESBLs基因,3株同时检出含有3种ESBLs基因.敏感性测定结果显示,分离菌大多呈现多重耐药,分离菌除对替加环素(18.2%)和阿米卡星(36.4%)的耐药率较低外,对其他药物呈现出较高的耐药率,其中对阿莫西林的耐药率高达97.7%,对头孢曲松、环丙沙星、土霉素、四环素、红霉素的耐药率均在75.0%以上.此外发现,同时携带多个耐药基因的菌株耐药率较高.中药复方白头翁汤对分离菌表现出了一定的抑菌活性,其MIC值为204.8 g/L.14种抗菌药分别与白头翁汤联用后,耐药率均有不同程度下降,其中头孢类药物、氟喹诺酮类药物与白头翁汤联用后,耐药率下降较为明显,如头孢曲松由84.1%下降至56.8%,环丙沙星由75.0%下降至45.5%.综上,NDM和ESBLs耐药基因在肠杆菌科细菌中已有一定的流行,同时携带NDM和ESBLs多个耐药基因的菌株耐药较为严重.白头翁汤与抗菌药联用能在一定程度增强耐药菌株的敏感性,为临床相关感染的防治提供理论依据.

Outcome of Early Neurological Rehabilitation Patients Colonized with Extended-Spectrum Beta-Lactamase (ESBL) Producing Bacteria

Colonization with multidrug-resistant germs, in particular methicillin-resistant Staphylococcus aureus (MRSA) and extended-spectrum betalactamase producing bacteria (ESBL), is an emerging threat in early neurological rehabilitation. This study examined whether colonization with ESBL bacteria had deteriorating effects on neurological rehabilitation patients because of contact precautions (CP). Medical records have been carefully reviewed with respect to colonization with ESBL, outcome variables (functional independence), morbidity, and length of stay (LOS). 148/643 (23.0%) patients were ESBL positive on admission. ESBL carriers had a significantly longer LOS in early neurological rehabilitation (67.5 (42.0) vs. 25.8 (24.5), p < 0.001), worse functional status on admission (Barthel Index (BI) 13.0 (5.8) vs. 25.6 (24.1), p < 0.001), worse Glasgow Coma Scale (9.7 (3.8) vs. 12.0 (3.3), p < 0.001), worse Coma Remission Scale (9.5 (6.4) vs. 14.0 (6.8), p = 0.001), more codiagnoses (18.8 (5.1) vs. 13.3 (5.5), p < 0.001), and higher Patient Clinical Complexity Levels (PCCL). The outcome was significantly worse among ESBL positive patients (BI 28.2 (21.7) vs. 47.4 (31.0), p < 0.001;Early Rehabilitation Index -43.0 (51.7) vs. -26.0 (35.4), p < 0.001). ESBL patients had the same amount of therapy per day (136.2 (20.2) vs. 140.2 (18.7) min/day, n.s.), but the overall sum was significantly larger in the ESBL group due to longer LOS (p < 0.001). Mortality of both groups was comparable (3.8% vs. 4.1%). 54.3% of ESBL negative patients were discharged to home, but only 34.5% of ESBL colonized. 48% of ESBL positive patients were discharged to a nursing home, but only 25.1% of the ESBL free patients. Functional recovery of ESBL carriers undergoing neurological early rehabilitation is worse than that of patients without multidrug-resistant germs. Poorer outcome is not resulting from less therapy due to CP, but from functional status and higher morbidity on admission.

Appendical Perforation by Infection with Extended-Spectrum Beta-Lactamase (ESBL)-Producing <i>Escherichia coli</i>: Case Report

We report the very rare case of a huge appendical abscess with extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli (E. coli) as the pathogen. There have been several reports of appendical infections such as appendicitis and appendical abscess caused by ESBL-producing bacteria in adults. The treatment of ESBL-producing E. coli infection is specific, and ESBL-producing bacteria have recently been reported as pathogens associated appendicitis in children. To the best of our knowledge, this is the second report of perforated appendicitis with abscess due to ESBL-producing E. coli. We discuss the diagnostic modalities and treatments for appendical abscess with ESBL-producing E. coli. and propose that the patients with perforated appendicitis and abscess formation due to ESBL-producing E. coli should be administered the antibiotic MEPM within 2 weeks to treat the abscess more effec-tively without producing other multidrug-resistant bacteria.

不同家禽产ESBLs沙门菌的流行分布与耐药分析

了解胶东地区不同家禽携带沙门菌的流行分布及其耐药现状,为有效防控家禽沙门菌的流行传播及遏制其耐药提供依据。采用细菌的常规分离培养、质谱法、PCR法和微量肉汤稀释法等,对2021年8—10月在胶东5个地区3种家禽养殖场采集的3150份泄殖腔拭子进行沙门菌分离鉴定、血清型鉴定、药敏试验及β-内酰胺酶主要耐药基因的检测,利用统计学方法进行差异显著性分析。结果发现:(1)共分离获得194株沙门菌(6.16%)。水禽源沙门菌的携带率(14.36%)比肉鸡(5.04%)、蛋鸡(1.15%)高。(2)较多的血清型为S.Enteritidis(38.14%)、S.Kentucky(21.65%)、S.Senftenberg(14.95%)、S.Indiana(12.37%)、S.Typhimurium(8.76%)为主。肉鸡和水禽(均为7种)的沙门菌血清型较蛋鸡(3种)多,但均以S.Enteritidis为主。(3)110株禽源沙门菌对氨苄西林、异磺胺异噁唑、四环素3种药物耐药相对严重(58.18%~77.27%),未检测到美罗培南的耐药菌株。水禽和肉鸡源菌株较蛋鸡耐药严重,尤其对阿莫西林/克拉维酸(P=0.031)和四环素(P=0.007)的耐药差异显著。(4)81株(73.64%)禽源沙门菌为多重耐药,共有43种耐药谱型,肉鸡(25种)和水禽(22种)源菌株的耐药谱型远多于蛋鸡(8种)。(5)110株沙门菌中检测到3种耐药基因:blaCTX-M(70.00%)、blaTEM(51.82%)和blaOXA(26.36%),常见的耐药基因组合类型为blaCTX-M+blaTEM,且耐药基因与耐药表型间存在一定的相关性(P≤0.001)。由此可见,胶东地区的家禽均携带一定比例的沙门菌,但不同品种家禽的流行分布存在差异。不同家禽之间携带血清型的种类也有一定的差异,但携带最多的血清型均为S.Enteritidis。分离菌株耐药情况较为严重,耐药谱复杂多样。禽源沙门菌对β-内酰胺类药物耐药主要是blaCTX-M+blaTEM基因的表达所致。

Diagnostic Validity of Cica Beta Test 1 for the Detection of Extended Spectrum Beta-Lactamase (ESBL) Producing Gram Negative Bacteria by Comparing with Phenotypic Method

Background: Detection of extended spectrum beta lactamase producing bacteria is an important issue in the clinical settings. Objective: The purpose of the present study was to validate the Cica Beta Test 1 for detection of extended spectrum beta-lactamase (ESBL) producing bacteria. Method: This analytical type of cross-sectional study was carried out in the Department of Microbiology and Immunology at Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka from January 2006 to December 2006 for a period of one (01) year. All the patients presented with the clinical features of urinary tract infection and surgical as well as burn wound infection at any age with both sexes were selected as study population. All bacteria were isolated and identified by their colony morphology, staining characters, pigment production, motility and other relevant biochemical tests. Phenotypic confirmation of ESBLs producing isolates were done by inhibitor potentiated disc diffusion test according to CLSI recommendation. The Cica Beta Test 1 was performed according to the manufacturer’s instructions. Result: A total number of 288 Gram negative bacteria were isolated. Among these isolates Cica Beta test 1 was positive in 97 strains and phenotypic confirmatory test was positive in 89 strains. The test sensitivity of Cica Beta Test 1 was 100% (95% CI 95.9% to 100.0%). Specificity of the test was 96.0% (95% CI 92.2% to 98.2%). The positive predictive value (PPV) and negative predictive value (NPV) were 92.7% (95% CI 84.5% to 95.7%) and 100.0% (95% CI 98.0% to 100.0%) respectively. The accuracy of the test was 97.2% (95% CI 95.1% to 99.1%). Area under ROC curve = 0.980 (95% CI 0.964 to 0.996);p value 0.0001. Conclusion: In conclusion, Cica Beta Test 1 is very high sensitivity and specificity for the detection of ESBL from Gram negative bacteria.

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.

中药活性成分对产ESBLs大肠埃希菌增敏效应研究

为探究中药活性成分与抗菌药物联合对产ESBLs大肠埃希菌的体外抗菌效果及增敏效应,本研究分别对其最小抑菌浓度(minimum inhibitory concentration,MIC)进行了测定,并在此基础上将倍比稀释的1/2MIC备选中药联合2MIC抗菌药物对产ESBLs大肠埃希菌进行连续传代培养;通过对联合用药及单独抗菌药物MIC进行比较,来判断中西药联合对产ESBLs菌株的增敏作用效果。结果表明:6种中药提取物中,小檗碱的杀菌效果最佳(16μg/mL),丁香酚(64μg/mL)、黄芩苷(256μg/mL)和没食子酸(256μg/mL)其次,原儿茶酸和异甘草酸抑菌效果较差;在联合应用研究中发现,小檗碱与GEN、APR、MMP联用后其最小抑菌浓度分别降低至1.25、0.02、0.02μg/mL,没食子酸与GEN、APR、MMP联用后其最小抑菌浓度分别降低至1.25、2.50、0.01μg/mL。中药活性成分与抗菌药联合应用中,可提高抗菌药对产ESBLs大肠埃希菌的抗菌效果,增敏效应甚至提高200倍以上,且随着传代次数增加,抗菌药物的MIC逐代降低。该研究为临床上大肠杆菌病的中药防治以及开发新兴的中药抑菌剂提供了参考依据。

Prevalence of Extended-Spectrum Beta-Lactamase-Producing Strains Isolated at Zinder National Hospital (ZNH) in 2021 and Their Antibiotic Susceptibility Profile

Purpose: Bacterial resistance to antibiotics has become a global public health problem. Enterobacteriaceae ESBL is among the most incriminated in this emergence which reduces the therapeutic possibilities. Thus, the objective of this study is to determine the prevalence of the extended-spectrum beta- lactamase (ESBL) producing Enterobacteriaceae at ZNH and their antibiotic susceptibility profile. Materials and Methods: This is a prospective study carried out over 5 months in all hospitalized and non-hospitalized patients in whom a culture was taken for the diagnosis of an infection. The search for ESBL is done by the double disc diffusion method. Results: In total, 21 out of 45 of our strains are ESBL-producing, i.e. a frequency of 46.7%. The mean age is 41.62 (±22.90) with extremes of 2.6 - 78 years. The distribution of ESBL producing species showed a predominance of E. coli with 66.7% followed by K. pneumoniae and K. oxytoca each 9.5%. All ESBL strains were resistant to Amoxicillin, Cefalotin, Pipiracillin, Piperacillin + tazobactam, Ticarcillin, Ticarcillin + clavulanic acid. Resistance to C3G and Aztreonam was each 95.5%, to Amoxicillin/clavulanic acid 9.1%. All strains were sensitive to imipenem. E. coli strains showed resistance: 85.7% to ciprofloxacin, 50% to Amikacin, 57.1% to Gentamicin. For K. pneumoniae, it is 66.7% for Gentamicin and Ciprofloxacin. Conclusion: Our study reports a high prevalence of ESBL at the HNZ. This must be taken into account in order to monitor this phenomenon which constitutes a public health problem. The study also reports sensitivity to Amoxicillin/clavulanic acid and Aminoside which can be an alternative.

Increasing Incidence of Extended-Spectrum Beta-Lactamase-Producing Enterobacteriaceae (ESBL) and the Relation to Consumption of Broad-Spectrum Antimicrobial Agents 2003-2011 in a Large Area of Copenhagen, Denmark

Purpose: To investigate 1) the development in the incidence of ESBL-producing bacteria in hospitals and primary health care, 2) the contribution of primary health care to the incidence of ESBL-producing bacteria, and 3) the development in resistance patterns for all Escherichia coli and Klebsiella pneumoniae isolates in relation to antimicrobial consumption in hospitals and primary health care. Methods: ESBL-data were retrospectively collected from bacterial isolates from all specimens received at the Department of Clinical Microbiology from 2003 to 2011 together with the corresponding patient data. ESBL-production was detected in isolates from 1067 of 59,373 patients (1.8%) with an E. coli infection and in 263 of 8660 patients (3.0%) with a K. pneumoniae infection. Results: From 2003 to 2009, an increase in patients with an ESBL-producing isolate occurred in both hospitals and primary health care at the same time as an increased consumption of broad-spectrum antimicrobial agents was seen. Interventions to reduce prescription of cephalosporins and ciprofloxacin at the hospitals from 2010 resulted in a remarkable decrease in patients with ESBL-producing K. pneumoniae whereas a continuing increase was seen in patients with ESBL-producing E. coli both at hospitals and in primary health care. The proportion of patients with community-acquired ESBL-producing E. coli was stable with an increase of only 1.4% from 2007 to 2011. Conclusions: Reduction in prescription of broad-spectrum antimicrobial agents at the hospital level had an important impact on the incidence of ESBL-producing K. pneumoniae, but not on ESBL-producing E. coli.

探讨直接药敏试验在ESBLs细菌血流感染诊断中的应用评估

用于评估直接药敏试验在ESBLs细菌血流感染诊断中的临床应用价值。方法 收集2021年9月-2022年8月重庆市某三甲医院经过镜检为单一革兰阴性菌的阳性血培养标本,使用临床和实验室标准研究所(CLSI)建立的的标准化直接药敏试验方法进行快速药敏试验,选取ESBLs标本结果并与Vitek2 Compact全自动微生物鉴定与药敏分析仪结果进行比较。结果 本研究经常规鉴定为ESBLs菌共45株,包括肺炎克雷伯菌4株、产酸克雷伯菌1株及大肠埃希菌40株。本研究总分类一致率为90.0% (241/265),极重大错误率为0%,重大错误率为3%(8/265),微小错误率为6.1%(16/285)。其中氨苄西林(AMP)为100% (40/40),氨曲南(ATM)为91.2% (41/45),头孢他啶(CAZ)为71.1% (32/45),头孢曲松(CRO)为93.3% (42/45),妥布霉素(TOB)为95.6% (43/45),复方新诺明(SXT)为95.6% (43/45)。氨苄西林、头孢他啶、氨曲南、头孢曲松和复方新诺明的阳性预测值达100%,氨苄西林和妥布霉素的阴性预测值达100%。结论 经过本研究的验证,CLSI法总体分类一致率为90.9% ,VME为0%,ME为3%,mE为6.1%,符合CLSI M52标准,可被被本实验室接受和应用于日常工作。尽管仍有不足和改进之处,但随着评估工作的进一步深入和发展,CLSI在快速药敏纸片扩散试验适用范围、快速结果判断等内容将会不断完善,标准化直接药敏纸片扩散法将会成为临床实验室对肠杆菌目细菌的一种有价值的抗菌管理方法。

超广谱β-内酰胺酶(ESBLs)检测与耐药性菌株分布的关联研究

超广谱β-内酰胺酶(ESBLs)是一类能够水解广谱β-内酰胺类抗生素的酶,其产生与耐药性菌株的分布密切相关。本研究旨在探讨ESBLs检测与耐药性菌株分布的关联,并为临床治疗和抗菌药物的合理使用提供依据。在本研究中,我们收集了157个临床样本,并进行了ESBLs检测和耐药性菌株分布的分析。结果显示,ESBLs阳性菌株的耐药性明显高于ESBLs阴性菌株,表明ESBLs的检测结果与耐药性菌株的分布存在显著的关联性。进一步的分析发现,不同病原菌种类与ESBLs的产生和耐药性之间存在差异。某些病原菌株更容易产生ESBLs,并且这些菌株具有更高的耐药性水平。因此,ESBLs的检测可以作为评估菌株耐药性的重要指标,有助于临床治疗和预防策略的制定。然而,本研究还存在一些限制,包括样本量有限和研究范围局限于特定地区或医疗机构。未来的研究可以扩大样本规模,并在更广泛的区域开展调查,以更全面地了解ESBLs检测与耐药性菌株分布的关联。综上所述,ESBLs检测与耐药性菌株分布之间存在密切的关联,这对于指导临床治疗和抗菌药物的使用具有重要意义。进一步的研究和努力将有助于深入理解耐药性菌株的形成机制,并制定有效的预防和控制策略,以维护公众健康。

β-内酰胺酶抑制剂复合抗菌药物的使用量与产ESBLs细菌分离率关系研究

目的 探讨临床上产超广谱 β 内酰胺酶 (ESBLs)细菌分离率的增加 ,是否与含 β 内酰胺酶抑制剂的复合β 内 酰胺类抗菌药物使用量有关 ,为抗菌药物的规范合理使用提供依据。方法 用SPSS10 0统计软件包 ,统计分析 1998～ 2 0 0 2年 ,每年含β 内酰胺酶抑制剂的复合 β 内酰胺类抗菌药物使用量与产ESBLs的大肠埃希菌和肺炎克雷伯菌分离率间的相关性关系。结果 5年来含 β 内酰胺酶抑制剂的复合 β 内酰胺类抗菌药物使用总量从16 5 4kg/年增加到 15 6 86 8kg/年 ,增加了 84 8 4 % ;培养总样本数从 10 897份增加到 185 6 7份 ,增加了 70 4 % ;两者间相关系数r =0 884 ,P <0 0 5 ;抗菌药物使用总量与细菌分离株数间的相关系数r =0 4 4 9,P >0 0 5 ,与产ESBLs细菌总分离率间的相关系数r =0 933,P <0 0 5 ;年平均每份送检样本中此类抗菌药物的使用量与细菌分离株数间的相关系数r =0 389,P >0 0 5 ,与产ESBLs细菌总分离率间的相关系数r =0 889,P <0 0 5。结论 产ESBLs细菌分离率的增加与含 β 内酰胺酶抑制剂的复合 β 内酰胺类抗菌药物使用总量及年平均每份送检样本中此类抗菌药物的使用量呈正相关 ,提示临床使用抗菌药物应更具合理性。

青岛地区产ESBLs鸡源大肠杆菌耐药性调查与优势基因型分析

【目的】通过抗菌药物敏感性测定试验以及超广谱β-内酰胺酶(ESBLs)表型和基因型检测试验,了解青岛地区肉鸡养殖场产ESBLs大肠杆菌菌株的分布情况及耐药特征,分析ESBLs流行基因型和基因亚型,为指导临床合理使用抗菌药物、有效控制产ESBLs菌株的感染和流行提供依据。【方法】采用微量肉汤稀释法对249株大肠杆菌菌株进行抗菌药物敏感性测定试验,采用CLSI推荐方法进行ESBLs表型检测和确证实验,采用PCR方法、序列测定以及生物学分析软件进行ESBLs耐药质粒的DNA扩展和基因型分析,利用SPSS19.0软件对产ESBLs菌株与非产ESBLs菌株的耐药情况进行差异显著性分析。【结果】83.13%(207/249)的鸡源大肠杆菌菌株产ESBLs;产ESBLs菌株对7种抗菌药的耐药率高于非产ESBLs菌株,其中对庆大霉素、大观霉素、氨苄西林、阿莫西林/克拉维酸、头孢噻呋等5种药物差异显著(P<0.05),而产ESBLs菌株对四环素和氟苯尼考2种抗菌药的耐药率显著低于非产ESBLs菌株;产ESBLs菌株多重耐药程度显著高于非产ESBLs菌株,其多重耐药率分别为99.03%和92.86%(P=0.035);CTX-M型、TEM型和OXA型ESBLs菌株的检出率分别为100.00%、99.52%和47.83%,未检测出SHV型ESBLs菌株;产酶菌株分属于10个基因亚型,TEM-1型、CTX-M-65型和CTX-M-55型、OXA-1型是优势基因亚型,并首次从健康家禽中检测到基因重组嵌合体CTX-M-123和CTX-M-64。【结论】产ESBLs鸡源大肠杆菌菌株在青岛地区广泛流行和传播;产ESBLs菌株耐药相对非产ESBLs菌株严重;相比国内其它地区,CTX-M型和TEM型同样成为青岛地区产ESBLs鸡源大肠杆菌菌株的流行基因型,但基因亚型存在差异,TEM-1型、CTX-M-65型和CTX-M-55型、OXA-1型分别是各基因型的优势基因亚型。

阴沟肠杆菌去阻遏持续高产AmpC酶和超广谱β-内酰胺酶(ESBLs)的检测

目的：去阻遏持续高产ＡｍｐＣ酶，或产生超广谱β－内酰胺酶（ＥＳＢＬｓ），或同时高表达这两类酶，是阴沟肠杆菌对多种β－内酰胺类抗生素耐药的主要机制。方法：建立了一种改良的酶提取物三维试验法，在常规ＮＣＣＬＳ纸片扩散法基础上接种大肠杆菌ＡＴＣＣ ２５９２２，在头孢西叮药敏纸片周围放射性切出琼脂小槽，待测菌的粗酶提取物在槽内扩散，与头孢西叮纸片扩散相交。结果：由于ＡｍｐＣ酶水解头孢西叮，出现抑菌圈内生长细菌，这一现象能被加入槽内的邻氯西林抑制，而ＥＳＢＬｓ不能水解头孢西叮，无此现象。因邻氯西林不能抑制ＥＳＢＬｓ活性，同样用头孢由松取代头抱西叮纸片，用邻氯西林抑制槽内ＡｍｐＣ酶，可测出 ＥＳＢＬｓ。使用该法检测分别产 ＡｍｐＣ酶、 ＥＳＢＬｓ的标准株和 ２４株临床分离多重耐药的阴沟肠杆菌。结果各种标准株检测无误，２４株阴沟肠杆菌中，１４株去阻遏持续高产ＡｍｐＣ酶试验阳性，４株产ＥＳＢＬｓ试验阳性，５株此两类酶检测均阳性，１株此两类酶检测均阴性，原因待分析。结论：对于阴沟肠杆菌，这种改良的酶提取物三维试验法能较好地鉴别持续高产 ＡｍｐＣ酶和 ＥＳＢＬ的阴沟肠杆菌，并适用于临床常规检验。