Antibacterial activities of some plant extracts alone and in combination with different antimicrobials against multidrug-resistant Pseudomonas aeruginosa strains

Objective:To evaluate the possible in vitro interaction between ethanolic extracts of Rhus coriaria[R.coriaria)(seed),Sacropoterium spinosum(S.spinosum)(seed),Rosa damascena(R. damascene)(flower) and certain known antimicrobial drugs including oxytetracycline HCl, penicillin C,cephalexin,sulfadimethoxine as sodium,and enr of loxacin.This synergy study was carried out against 3 clinical strains of multidrug-resistant Pseudomonas aeruginosa (P.aeruginosa).Methods:Evaluation of synergy interaction between plant extracts and antimicrobial agents was carried out using microdilution method.Results:The results of this study showed that there is a decrease in the MIC in case of combination of ethanolic plant extracts and test antimicrobial agents.The most interesting result was that the combination between R. coriaria and these antibiotics,showed a high decrease in minimum inhibitory concentration(MIC), and a strong bactericidal activity against these strains.Conclusions:These results may indicate that combinations between R.coriaria extract and these antibiotics could be useful in fighting emerging drug-resistance P.aeruginosa,which may due to that R.coriaria extract contain natural inhibitors working by different mechanisms or inhibiting efflux pumps.Now we have experiments underway leading to the identification of the active molecules present in R.coriaria.Further,in vivo experiments are needed to confirm pseudomonal protection.

Two bacterial infection models in tree shrew for evaluating the efficacy of antimicrobial agents

Animal models are essential for the development of new anti-infectious drugs.Although some bacterial infection models have been established in rodents,small primate models are rare.Here,we report on two bacterial infection models established in tree shrew（Tupaia belangeri chinensis）.A burnt skin infection model was induced by dropping 5×106 CFU of Staphylococcus aureus on the surface of a wound after a third degree burn.This dose of S.aureus caused persistent infection for 7 days and obvious inflammatory response was observed 4 days after inoculation.A Dacron graft infection model,2×106 CFU of Pseudomonas aeruginosa also caused persistent infection for 6 days,with large amounts of pus observed 3 days after inoculation.These models were used to evaluate the efficacy of levofloxacin（LEV） and cefoperazone（CPZ）,which reduced the viable bacteria in skin to 4log10 and 5log10 CFU/100 mg tissue,respectively.The number of bacteria in graft was significantly reduced by 4log10 CFU/mL treatment compared to the untreated group（P0.05）.These results suggest that two bacterial infection models were successfully established in tree shrew using P.aeruginosa and S.aureus.In addition,tree shrew was susceptible to P.aeruginosa and S.aureus,thus making it an ideal bacterial infection animal model for the evaluation of new antimicrobials.

Antimicrobial Susceptibility,Biofilm Production and Adhesion to HEp-2 Cells of Pseudomonas aeruginosa Strains Isolated from Clinical Samples

A hundred Pseudomonas aeruginosa strains from several clinical specimens from five hospitals in Sao Luís-MA were evaluated for biofilm production, prevalence of the gene algD, adhesion to HEp-2 cells and antimicrobial susceptibility. The most affected clinical specimens and hospital sectors were also evaluated. Most isolates were obtained from the tracheal aspirate (21.0%) and the most affected hospital sector was the ICU (43.0%). The antibiotics with the highest sensitivity rate were amikacin, piperacillin/tazobactam, fluoroquinolones, gentamicin and meropenem and the ones with the highest resistance rate were aztreonam, ceftazidime and cefepime. All samples were sensitive to polymyxin B. In relation to the expression of the gene for ESBL, 50.0% (17/34) of the multiresistant strains showed the enzyme TEM. Most strains showed high hydrophobicity and 96% of the isolates produced biofilm on a polystyrene microplate, 52% were capsule producers, 19% showed mannose-sensitive fimbriae and 39% expressed the gene algD. We observed adhesion to HEp-2 cells and to the coverslip. These factors may be reported in the pathogenesis of this bacterium, what represents a potential risk for colonization of medical devices which favor the establishment of chronic nosocomial infections.

Evaluation of rational use of antimicrobial agents in a Brazilian intensive care unit

The present study sought to assess the rational use of antimicrobial agents in a Brazilian intensive care unit (ICU) and its association with antimicrobial resistance in elderly patients admitted to the unit. Results: Choice of empiric and sensitivity-guided therapy was inadequate in > 80% and 59% of cases respectively. Inadequate antimicrobial therapy, whether empiric or sensitivity-guided, was positively correlated with bacterial resistance (r = 0.316;p = 0.001). Sensitivity testing revealed a 46.5% resistance rate to eight out of the ten most commonly used antibiotics. Multiple drug-resistant organisms were found in 40.8% of patients. A significant increase was observed in the number of multidrug-resistant samples between 2006/2007 and 2008 (r = 0.41, p = 0.006), (r = 0.598, p = 0.001), (r = 0.688, p = 0.00). Conclusion: We found a high rate of antibiotic misuse in the study sample. Inadequate therapy was correlated with resistance to antimicrobial agents.

Design and characterization of a bi-functional bybrid antibacterial peptide LLM against Pseudomonas aeruginosa

Objective:To design a bifunctional antimicrobial peptide with high antibacterial activity and endotoxin neutralization against P.aeruginosa and explore its bactericidal properties.Methods:The neutralizing endotoxin peptides and antimicrobial peptide against P.aeruginosa were connected by a GGGS-linker to get a bi-functional bybrid peptide.Its structural parameter was tested by EMBOSS software.The minimum inhibitory concentration(MIC),minimum bactericidal concentration(MBC)and bactericidal kinetics against P.aeruginosa were determined.Its effect on endotoxin neutralization and hemolysis were also evaluated.Results:We designed and obtained a bybrid peptide LLM,which carried+8 positive charge with high activity against P.aeruginosa and neutralizing endotoxin.The MIC of LLM against P.aeruginosa CMCC10104 and P.aeruginosa ATCC 9027 were 2 and 4μmol/L,and MBC/MIC equal 1.LLM showed rapid anti-P.aeruginosa effects and significantly neutralized the endotoxin released,and not exhibited hemolysis as high as 115μmol/L(400μg/mL).Conclusion:The MICs of LLM against P.aeruginosa were 2~4μmol/L,it showed significant activity of anti-P.aeruginosa and neutralizing endotoxin,and could kill bacteria quickly,and did not show significant hemolytic under 115μmol/L.

Discovery of synergistic activity of fluoroquinolones in combination with antimicrobial peptides against clinical polymyxin-resistant Pseudomonas aeruginosa DK2

Polymyxin B(PB),as the last-line of defense against multidrug-resistant Gram-negative bacteria,has caused resistance to P.aeruginosa recently.Fortunately,synergistic treatment could preserve the last class of antibiotics and reduce the emergency of drug resistance.Here,we performed a screen of 970 approved drugs synergized with PB against the P.aeruginosa DK2,which is severely resistant to PB,MIC=512μg/mL.Encouragingly,we found fluoroquinolones could synergy with PB and achieved an obvious reduction in MIC of PB below the clinical susceptible breakpoint(2 μg/mL).Especially,gemifloxacin achieved the highest synergistic effect with PB,leading to a 4096-fold MIC reduction(reduced from512 μg/mL to 0.125 μg/mL).Furthermore,synergistic effect was also observed in the combination of gemifloxacin and colistin.Finally,outer membrane permeabilization assay showed that gemifloxacin could increase the permeability of bacterial cell membranes for P.aeruginosa which partly explained the synergy mechanism.These results indicate that fluoroquinolones represent attractive synergists to address the emerging threat of polymyxin-resistant infections.

Prevalence and Antimicrobial Susceptibility Profile of Metallo-<i>β</i>-Lactamase Producing <i>Pseudomonas aeruginosa</i>Isolates at Kenyatta National Hospital

Pseudomonas aeruginosa is a major cause of nosocomial infections with high mortality rates. The organism is highly resistant to most classes of drugs used and can develop resistance during treatment. One of the resistance mechanisms of P. aeruginosais is Metallo-β-Lactamase (MBL) production. MBL producing P. aeruginosa is a major health concern given it’s resistance to almost all available drugs. The prevalence of this resistant strain is unknown since there is no standardized method for testing MBL production. This was a laboratory based cross-sectional prospective study that was carried out from September 2015 to March 2016 at Kenyatta National Hospital. Ninety-nine isolates of P. aeruginosa were collected during the period and tested for antimicrobial susceptibility and isolates found to be resistant to imipenem tested for MBL production. The results indicated high resistance of P. aeruginosa to commonly used drugs. Of the isolates tested 69.7% were resistant to piperacillin, 63.6% were resistant to aztreonam, 58.6% were resistant to levofloxacin, 55.6% were resistant to cefipime, 65.7% were resistant to ceftazidime, 68.7% were resistant to ticarcillin-clavulanate, 72.2% were resistant to meropenem, 64.9% were resistance to imipenem while 86.4% of urine isolates were resistant to ofloxacin. Of the isolates resistant to imipenem 87.3% were found to be MBL producers. In conclusion, P. aeruginosais highly resistant to the drugs currently is used for treatment and resistance to carbapenems is largely due to MBL production.

Antimicrobial resistance in clinically important biofilms

A biofilm contains a consortium of cohesive bacterial cells forming a complex structure that is a sedentary, but dynamic, community. Biofilms adhere on biotic and abiotic surfaces, including the surfaces of practically all medical devices. Biofilms are reported to be responsible for approximately 60% of nosocomial infections due to implanted medical devices, such as intravenous catheters, and they also cause other foreign-body infections and chronic infections. The presence of biofilm on a medical device may result in the infection of surrounding tissues and failure of the device, necessitating the removal and replacement ofthe device. Bacteria from biofilms formed on medical devices may be released and disperse, with the potential for the formation of new biofilms in other locations and the development of a systemic infection. Regardless of their location, bacteria in biofilms are tolerant of the activities of the immune system, antimicrobial agents, and antiseptics. Concentrations of antimicrobial agents sufficient to eradicate planktonic cells have no effect on the same microorganism in a biofilm. Depending on the microbial consortium or component of the biofilm that is involved, various combinations of factors have been suggested to explain the recalcitrant nature of biofilms toward killing by antibiotics. In this mini-review, some of the factors contributing to antimicrobial resistance in biofilms are discussed.

不同酚类成分及其组合对P.aeruginosa PAO1的抑制效果研究

为研究茶叶酚类成分及其复方对P.aeruginosa PAO1的体外抑制作用,筛选出用药量最低的最佳抑菌组方,采用倍比稀释法结合刃天青显色测定5种酚类成分对P.aeruginosa PAO1的最小抑菌浓度(MIC),并采用响应面法研究对P.aeruginosa PAO1具有较强抑制作用的最佳配伍。结果表明5种酚类成分对P.aeruginosa PAO1均有不同程度的抑制作用,5种茶叶活性成分对P.aeruginosa PAO1的抑菌性大小为:EGCG>TF60=ECG>EGC>EC。响应面分析结果表明,EGCG、EGC、ECG、TF60这4种酚类成分以1.0∶4.0∶4.81∶4.0的比例配伍时对P.aeruginosa PAO1具有最佳抑菌效果。

Microbiological safety of spices and their interaction with antibiotics:implications for antimicrobial resistance and their role as potential antibiotic adjuncts

Objectives:A study was undertaken to:1.examine contaminating bacteria on a variety of spices purchased at retail market;2.investigate if spice bacterial enrichments alter the phenotype of 13 bacterial foodborne and clinical pathogens and 1 probiotic organism;and 3.investigate if spices can alter antimicrobial activity of seven clinical antibiotics against 16 bacterial foodborne/clinical pathogens.Materials and Methods:Microbiological examination was undertaken employing 27 spice varieties with four antibiotics and 15 bacterial pathogens.Results:Bacteriological contamination levels varied amongst spice varieties,ranging from Kasmin chilli powder(7.5×10^(6)cfu/g;log10^(6).88 cfu/g)to ginger(1.5×10^(4)cfu/g;log_(10)4.18 cfu/g);mean contamination was 1.38×10^(6)cfu/g(log_(10)6.14 cfu/g).Four species within the genus Bacillus were identified(Bacillus megaterium,Bacillus subtilis,Bacillus licheniformis,and Bacillus cereus).There was no phenotypic difference with the 14 bacteria,with bacterial colony growth/proliferation,pigment production,or with adhesin and mucoid production.None of the spice cultures inhibited any of the 14 bacterial species examined.In the case of doxycycline,amoxicillin,colistin,erythromycin,and piperacillin/tazobactam,the zone of inhibition increased with the inclusion of the 26 spice varieties,suggesting that the spices were interacting synergistically with the antibiotic,thus making the antibiotic more potent against the bacteria tested.Conclusions:This study demonstrates a positive interaction between spices and conventional antibiotics.Given the burden of antimicrobial resistance(AMR)worldwide,but particularly in South Asian countries(India and Pakistan),any food-related innovation that can help maximize the potency of existing antibiotics is to be encouraged and developed.The specific mechanism as to how spices increase the potency of antibiotics needs to be elucidated,as well as novel food(spice)delivery modalities including novel medicinal foodstuffs or functional foods,that can harness this beneficial effect for medicine and society.

Resistance Trends among <i>Pseudomonas aeruginosa</i>Isolates in a Tertiary Care Centre in South Gujarat

It is necessary to determine the susceptibility pattern of clinical isolates especially nosocomial one in the clinical settings for making strategy for effective empirical treatment & to reduce incidence of multidrug resistant bugs. Aim of this study was to detect the antimicrobial susceptibility pattern of P. aeruginosa isolates from clinical samples between January 2014 to December 2015, received at department of Microbiology, GMC, Surat. Clinical isolates were confirmed as P. aeruginosa by phenotypic methods/Vitek2 compact system as per availability. Genetic sequencing could not be performed due to unavailability. Antimicrobial susceptibility tests were performed by Kirby-Bauer disc diffusion method/Vitek2 compact system & Interpretation was done according Clinical and Laboratory Standards Institute (CLSI) of that year [1] [2]. Seven hundred fifty seven P. aeruginosa strains were studied during the study period. Most of the isolates were from surgery ward (62%), followed by orthopaedic ward (15%). 65% of the total isolates were from swab samples followed by urine (7%), pus, fluid (5%) & devices (4%). 60% isolates were resistant to Ceftazidime & for other drugs resistance pattern was as follows: Cefepime (52%), Levofloxacin (49%), Ticarcillin/clavulanic acid (49%), Meropenem & Gentamycin (44%), Ciprofloxacin (43%), Amikacin (41%), Tobramycin (39%), Netlimycin (36%), Piperacillin (32%), Aztreonam (31%), Piperacillin/tazobactam (26%), Imipenem (23%) , Doripenem (12%) & Gatifloxacin (10%). As there is predominance of isolates from surgical ward in present study & resistance to carbapenem group of drugs was also found, indicating that most of the infection caused by Pseudomonas aeruginosa may be nosocomial.

KL-0153, a novel inhibitor of Pseudomonas aeruginosa MexAB-OprM efflux pump

Pseudomonas aeruginosa is an opportunistic pathogen that contributes to high morbidity and mortality. MexAB-OprM is the main efflux pump among the Resistance-Nodulation-Division family multi-drug effiux systems, which contribute greatly to the multidrug resistance of P. aeruginosa. Effiux pump inhibitors （EPIs） of MexAB-OprM could enhance the activity of the antibiotics effiuxed by MexAB-OprM, and thus they might be useful in the clinic as antibacterial synergistic agents. In this work, a new EPI of MexAB-OprM, KL-0153, was discovered by screening of a small molecular library. Its inhibition of MexAB-OprM was confirmed by assays of synergistic activity and EB accumulation. The activity of KL-0153 was shown to be synergistic with antibiotics effiuxed by MexAB-OprM when they were tested against strains expressing MexAB-OprM, especially so for the strains that express MexAB-OprM at high levels. KL-0153 showed more activity than the positive drug carbonyl cyanide m-chlorophenylhydrazone in the EB accumulation assay. It cannot be neglected that KL-0153 has significant liver and kidney toxicity. However, KL-0153 may be a lead comoound for the research and development of new tvoes of EPIs.

Analysis of Drug Resistance Spectra and Conjugative Plasmid Carrying Rates of P.aeruginosa and Acinetobacter

Antimicrobial susceptibility test was performed on 57 clinical isolates of P. aeruginosa and 36 clinical isolates of Acinetobacter with 11 antimicrobial agents including getamicin, amikacin, ciprofloxacin, ofloxacin, fleroxacin, piperacillin, cefotaxime, cefoperazone/sulbactam, ceftazidime, cefoperazone and doxycycline. Transferable drug resistance plasmid carrying rates of these clinical isolates were also studied. On the basis of the in vitro activities, 52.63%(30/57) of the isolated strains of P. aeruginosa were susceptible to antimicrobial agents selected (except doxycycline), 41.67%(15/36) of the isolated strains of Acinetobacter were susceptible to 11 antimicrobial agents. The sensitivity rate of P.aeruginosa and Acinetobacter to antimicrobial agents selected was 70% or greater to all except doxycycline. Furthermore, the sensitivity rate of P.aeruginosa to amikacin ciprofloxacin, ceftazidime, cefoperazone, cefoperazone/sulbactam, and that of Acinetobacter to cefoperazone/sulbactam, amikacin was more than 90%,among them amikacin, cefoperazone/sulbactam being the most effective. Plasmid analysis showed that 15.79%(9/57) P.aeruginosa strains and 13.89%(5/36) Acinetobacter strains carried plasmid. Conjugative plasmid carrying rates of P. aeruginosa strains and Acinetobacter strains were 7.02%(4/57), 13.89%(5/36), respectively. Conjugative plasmid didn′t play an important role in the formation and dissemination of drug resistance of P. aeruginosa and Acinetobacter.

Detection of Pathogenic Microorganisms from Burn Patients Admitted in Tertiary Medical College Hospital and Their Antimicrobial Patterns

Object: To isolate and identify the microorganisms from the burn patients admitted to the National Institute of Burn and Plastic Surgery Unit in Tertiary Medical College Hospital, Bangladesh. A total number of fifty wound surface swab samples of first and second-degree burn patients were collected and the microbial analysis as well as the study of antibacterial susceptibility was conducted. The study showed the bacterial isolates were found. 45 (90%) of wound swab were positive among 50 and only 5 samples (10%) were negative in bacterial growth, which presented invasive burn wound infection from both sex age groups marked 12 - 60 years. The total viable count TVC-11651 CFU/plate was found and the highest amount in the second-degree burn patients. The results showed that Pseudomonas aeruginosa was common in all positive samples 6636 CFU/plate (57%) followed by Staphylococcus aureus 4070 CFU/plate (35%), Klebsiella spp. 450 CFU/plate (5%), Proteus spp. 243 CFU/plate (2%), and E. coli 162 CFU/plate (1%). Most of the pathogens were found to be drug-resistant while several isolates were noted to be multi-drug resistant. The growth of multidrug-resistant organisms should be considered as a serious risk factor in a burn unit. Aggressive infection control measures should be applied to limit the emergence and spread of multidrug-resistant pathogens.

某三甲医院尿路感染患者病原菌分布及药敏分析

目的了解自贡市第三人民医院尿路感染患者病原菌分布及药敏耐药性特点,为临床医师合理选用抗菌素及控制院内感染、降低细菌耐药性提供帮助。方法收集2019年1月—2020年12月自贡市第三人民医院尿路感染就诊患者尿液标本3802份,采用MicroScan Walk/Away-40(美国SIEMENS公司)全自动微生物鉴定和药敏系统进行细菌鉴定和药敏试验。结果539株分离菌中革兰阴性菌411株,占比76.25%;革兰阳性菌128株,占比23.75%;其中前5位的菌株416株,依次为大肠埃希菌294株(54.55%)、粪肠球菌46株(8.53%)、肺炎克雷伯菌38株(7.05%)、屎肠球菌23株(4.27%)、奇异变形杆菌15株(2.78%)。前5位3种革兰阴性菌中,大肠埃希菌对复方新诺明、环丙沙星、头孢唑啉及左旋氧氟沙星耐药率均>50.00%,对头孢噻肟、头孢曲松、氨曲南和头孢吡肟耐药率均>40.00%,庆大霉素为35.71%,其余均在30.00%以内;肺炎克雷伯菌对复方新诺明耐药性最高为52.63%,其次是头孢唑林为42.11%、头孢噻肟为36.84%、环丙沙星和头孢曲松均为31.58%,其余均在30.00%以内;奇异变形杆菌,对复方新诺明耐药率最高为60.00%,其次环丙沙星为53.33%、妥布霉素为46.67%,头孢唑啉、庆大霉素和氨曲南均为33.33%,其余均在30.00%以内。前5位2种革兰阳性菌中,粪肠球菌,对四环素耐药性最高为86.96%,其次红霉素为76.09%、利福平为54.35%,环丙沙星为32.61%、左旋氧氟沙星和莫西沙星均为30.43%,其余均在30.00%以内;屎肠球菌,对红霉素、环丙沙星和左旋氧氟沙星耐药率均为100%,其次青霉素G为95.65%、莫西沙星为91.30%、利福平和阿莫西林/克拉维酸均为82.61%、四环素为65.22%,对大多数抗菌药物耐药率均较高,其中对万古霉素耐药率最低为4.35%,其次为利奈唑胺为5.26%、呋喃妥因为8.70%。结论临床医师在诊疗过程中,应加强与实验室合作,重视尿路感染的病原学检查,在选用抗菌药物治疗时应结合实验室病原学报告和药敏试验结果,合理使用抗菌药物,同时遏制细菌耐药性。

2015—2021年CHINET儿童患者临床分离不发酵糖革兰阴性杆菌耐药性变迁

目的了解CHINET中国细菌耐药性监测网儿童患者临床分离的不发酵糖革兰阴性杆菌的分布和耐药性变迁。方法按CHINET耐药监测统一方案使用纸片扩散法或商品化药敏试验自动测试仪进行药敏试验。按CLSI 2021年版标准判断结果。结果临床分离不发酵糖革兰阴性杆菌26987株中,主要以假单胞菌属和不动杆菌属细菌为主,其他各菌属均有不等检出。下呼吸道标本占51.1%,居于首位,脓液及伤口分泌物占16.5%,尿液标本占9.2%。这些菌株主要分离于内科病房(38.1%)、儿科ICU(26.8%)和外科病房(18.9%)。铜绿假单胞菌对氨曲南耐药率最高,为22.7%,对碳青霉烯类抗生素耐药率为15.6%,对其他抗菌药物耐药率均低于10%。碳青霉烯类耐药鲍曼不动杆菌检出率54.1%,明显高于铜绿假单胞菌的15.6%,2020年和2021年出现下降趋势。碳青霉烯类耐药铜绿假单胞菌在新生儿期患儿的检出率(34.7%)高于其他患儿;碳青霉烯类耐药鲍曼不动杆菌随患儿年龄增长检出率逐渐增高(39.9%~65.4%)。结论儿童分离铜绿假单胞菌和鲍曼不动杆菌对各种抗菌药物的耐药率呈锯齿形变化,对大多抗菌药物的耐药率有下降趋势。不同年龄段患儿中碳青霉烯类耐药菌株的检出率不同。不发酵糖革兰阴性杆菌的分布特征和不同菌属菌株的耐药特征存在差异。因此,在儿科对此类菌进行耐药监测十分必要。

湖南省细菌耐药监测网2012—2021年呼吸道分离菌耐药性监测

目的了解2012—2021年湖南省细菌耐药监测网呼吸道分离菌的分布和耐药性变迁。方法细菌鉴定和药敏试验统一按全国细菌耐药监测网(CARSS)细菌耐药监测技术方案执行,剔除重复菌株。按照美国临床实验室标准化协会(CLSI)2022年标准判断细菌对抗菌药物的敏感性,应用WHONET 5.6软件进行统计描述。结果2012—2021年湖南省细菌耐药监测网呼吸道标本共分离976984株细菌,其中革兰阳性菌185642株(19.0%),革兰阴性菌791342株(81.0%)。分离自成人患者呼吸道标本排名前五位的细菌是肺炎克雷伯菌(25.2%)、铜绿假单胞菌(17.0%)、鲍曼不动杆菌(14.6%)、大肠埃希菌(6.7%)和金黄色葡萄球菌(5.8%)。分离自儿童患者呼吸道标本排名前五位的细菌是金黄色葡萄球菌(17.7%)、肺炎链球菌(15.6%)、大肠埃希菌(13.5%)、肺炎克雷伯菌(13.1%)和流感嗜血杆菌(10.8%)。肺炎克雷伯菌、大肠埃希菌和阴沟肠杆菌对替加环素、头孢哌酮/舒巴坦、哌拉西林/他唑巴坦、碳青霉烯类、阿米卡星耐药率较低(<15%)。肺炎克雷伯菌对亚胺培南、美罗培南的耐药率分别从2012—2013年的3.5%、4.2%逐渐上升至2020—2021年的9.5%、11.5%,对头孢哌酮/舒巴坦、哌拉西林/他唑巴坦、阿米卡星、妥布霉素、环丙沙星和左氧氟沙星的耐药率呈上升趋势。大肠埃希菌和阴沟肠杆菌对氨曲南、氨基糖苷类和氟喹诺酮类的耐药率呈下降趋势。铜绿假单胞菌对多黏菌素耐药率较低(<6%),鲍曼不动杆菌对替加环素和多黏菌素耐药率较低(<6%)。铜绿假单胞菌对β-内酰胺类、氨基糖苷类和氟喹诺酮类耐药率下降。鲍曼不动杆菌对头孢哌酮/舒巴坦的耐药率从18.0%上升至43.7%,对哌拉西林/他唑巴坦、亚胺培南、氟喹诺酮类和米诺环素的耐药率呈上升趋势。未发现对万古霉素、替考拉宁和利奈唑胺耐药的金黄色葡萄球菌。成人和儿童患者耐甲氧西林金黄色葡萄球菌(MRSA)检出率分别为37.8%(14208/37594)、22.7%(10874/47882)。结论湖南省2012—2021年呼吸道分离细菌以革兰阴性菌为主,成人和儿童患者分离的优势细菌并不相同。大肠埃希菌、阴沟肠杆菌和铜绿假单胞菌对部分抗菌药物的耐药率不断下降。肺炎克雷伯菌对碳青霉烯类耐药率逐渐上升。应持续高效做好细菌耐药监测,为临床使用抗菌药物提供数据支持。

2015—2021年CHINET临床分离葡萄球菌属细菌耐药性变迁

目的了解2015-2021年中国不同地区临床分离葡萄球菌属细菌的分布及耐药变迁。方法按CHINET中国细菌耐药监测网统一的技术方案对临床分离的葡萄球菌采用纸片法和商品化药敏试验测试仪(机器法)进行药物敏感性试验;收集2015-2021年CHINET的葡萄球菌耐药监测数据,使用WHONET 5.6软件统计并按2021年CLSI折点标准判读结果。结果2015-2021年共分离非重复葡萄球菌属细菌204771株,其中金黄色葡萄球菌136731株(66.8%),凝固酶阴性葡萄球菌68040株(33.2%),7年间两者检出率均无明显变化。金黄色葡萄球菌主要分离自呼吸道标本(38.9±5.1)%、伤口脓液分泌物(33.6±4.2)%、血液(11.9±1.5)%;凝固酶阴性葡萄球菌主要分离自血液(73.6±4.2)%、脑脊液(12.1±2.5)%、胸腹水(8.4±2.1)%。金黄色葡萄球菌的科室来源主要为ICU(17.0±7.3)%、门急诊(11.6±1.7)%、外科(11.2±0.9)%;凝固酶阴性葡萄球菌的科室来源主要为ICU(32.2±9.7)%、门急诊(12.8±4.7)%、内科(11.2±1.9)%。金黄色葡萄球菌、凝固酶阴性葡萄球菌中甲氧西林耐药株的总体检出率分别为32.9%、74.1%,7年间MRSA检出率从42.1%下降至29.2%,MRCNS检出率从82.1%下降至68.2%。除甲氧苄啶-磺胺甲噁唑外,MRSA对各类抗菌药物的耐药率均高于MSSA。MRSA对庆大霉素、利福平、左氧氟沙星耐药率有所下降;MRCNS对庆大霉素、红霉素、利福平、甲氧苄啶-磺胺甲噁唑的耐药率有所下降,对左氧氟沙星的耐药率有所上升。未发现对万古霉素耐药的葡萄球菌菌株。对利奈唑胺耐药的MRCNS有所增多,7年间耐药率从0.2%上升至2.3%。结论葡萄球菌属细菌仍是革兰阳性菌中最主要的细菌。MRSA和MRCNS亦仍然是革兰阳性菌中最主要的耐药细菌。至今未发现对万古霉素和利奈唑胺耐药的金黄色葡萄球菌,但已有利奈唑胺耐药的MRCNS菌株检出,应加强监测和关注。

湖南省细菌耐药监测网2012-2021年肠球菌属细菌耐药性监测报告

目的了解湖南省临床分离肠球菌属细菌对各类抗菌药物的耐药情况及变迁。方法收集湖南省细菌耐药监测网成员单位2012—2021年临床分离的肠球菌属细菌耐药性监测数据,按照统一方法进行数据清洗后应用WHONET 5.6软件进行统计分析。结果2012—2021年共纳入110652株非重复肠球菌属细菌,主要为粪肠球菌、屎肠球菌,分别占46.9%(37774株)、45.9%(36968株),其次为鸟肠球菌(2.5%,1982株)、鹑鸡肠球菌(1.8%,1428株)、铅黄肠球菌(1.5%,1185株)。肠球菌属细菌主要标本来源为尿(51.8%,57350株),其次是分泌物(9.6%,10660株)、胆汁(8.5%,9377株)。2012—2021年粪肠球菌对氨苄西林、替考拉宁和万古霉素的耐药率分别为5.5%~12.0%、1.3%~2.0%、0.6%~1.4%,屎肠球菌对氨苄西林、替考拉宁和万古霉素的耐药率分别为69.2%~85.0%、1.5%~2.8%、0.7%~2.5%。除利奈唑胺和米诺环素,屎肠球菌对检测抗菌药物的耐药率均高于粪肠球菌。粪肠球菌、屎肠球菌对万古霉素的耐药率分别从2012年的1.4%、2.1%下降至2021年的0.6%、0.7%,呈下降趋势。结论肠球菌属临床分离菌对万古霉素和替考拉宁保持较好的敏感性,粪肠球菌、屎肠球菌对万古霉素的耐药率呈下降趋势。

2015-2021年CHINET临床分离沙雷菌属细菌耐药性变迁

目的了解国内主要地区临床分离沙雷菌属细菌对常用抗菌药物的耐药率及变迁。方法由CHINET中国细菌耐药性监测网参与成员单位将临床分离菌采用纸片扩散法或自动化商业药敏测试系统按CHINET统一技术方案进行仪器法药物敏感性试验。结果2015年1月—2021年12月从我国不同地区53所医院临床分离到的沙雷菌属17226株。分离的菌株数从2015年959株上升到2021年3588株,自门急诊患者中分离到的沙雷菌占7.3%(1265/17226),住院患者菌株占92.7%(15961/17226)。17226株沙雷菌属细菌中呼吸道标本占比最高(57.5%±2.5%),其次为血液标本(11.5%±1.5%)。7年连续监测发现除氨苄西林、头孢唑林及呋喃妥因外其他抗菌药物细菌耐药率均有所下降,亚胺培南和美罗培南虽然耐药率数值有所反复,但仍从8.1%和8.3%降到5.3%和5.2%。成年患者来源的菌株对头孢哌酮-舒巴坦、头孢他啶-阿维巴坦、头孢噻肟、亚胺培南、呋喃妥因和替加环素耐药率三级医院高于二级医院,其他抗菌药物耐药率均低于二级医院。分离自儿童患者的沙雷菌对头孢哌酮-舒巴坦、哌拉西林-他唑巴坦、阿米卡星、甲氧苄啶-磺胺甲唑和替加环素的耐药率低于5%。分离自ICU的菌株对抗菌药物的耐药率普遍高于其他监测科室。7年监测碳青霉烯类耐药肠杆菌目菌株检出率为8.2%。结论7年中沙雷菌属细菌耐药率呈缓慢下降趋势,继续加强标本及时送检及合理使用抗菌药物对细菌耐药率下降起着尤为重要的作用,落实医院感染控制可有效降低耐药细菌的发生。