产ESBLs、AmpC、KPC酶的葡萄糖不发酵细菌的耐药性分析及临床分布

目的了解本地区葡萄糖不发酵细菌中泛耐药菌（代表株铜绿假单胞菌、鲍曼不动杆菌、嗜麦芽窄食单胞菌）在临床标本中的分离与耐药情况,为临床合理使用抗生素提供指导。方法对临床分离的180株葡萄糖不发酵细菌进行分类鉴定和药敏试验,并用纸片扩散法筛选出产超广谱β-内酰胺酶（ESBLs）、头孢菌素酶（AmpC酶）及碳青霉烯类水解酶（KPC酶）的耐药菌株。结果在葡萄糖不发酵细菌的构成比中,其中产超广谱β-内酰胺酶（ESBLs）56株（31.1%）,产AmpC酶22株（12.2%）,KPC酶2株（1.1%）;同时产ESBLs和AmpC酶16株（8.9%）,同时产ESBLs、AmpC、KPC酶1株（0.6%）。3种主要葡萄糖不发酵细菌对头孢他啶、头孢三嗪、头孢噻肟、哌拉西林的耐药率最高,其中铜绿假单胞菌对阿米卡星、左氧氟沙星、环丙沙星耐药率较低,鲍曼不动杆菌对亚胺培南、左氧氟沙星耐药率较低,嗜麦芽窄食单胞菌对复方新诺明、环丙沙星耐药率较低。结论葡萄糖不发酵细菌中泛耐药菌特别是铜绿假单胞菌、鲍曼不动杆菌、嗜麦芽窄食单胞菌均有较高的多重耐药性,临床上应重视葡萄糖不发酵细菌引起的感染,根据药敏试验结果合理使用抗生素。     

嗜麦芽窄食单胞菌整合子I和ISCR1研究及ERIC-PCR基因分型

目的了解临床分离嗜麦芽窄食单胞菌的整合子I和ISCR1的分布情况及其基因型。方法分离临床85株嗜麦芽窄食单胞菌,用WHONET5.4分析菌株药敏情况,采用ERIC-PCR方法进行基因分型。采用PCR检测整合酶I、整合子I、ISCR1以及ISCR1携带的耐药基因。结果嗜麦芽窄食单胞菌对亚胺培南、氨曲南、庆大霉素、阿米卡星高度耐药,整合子I阳性菌株和整合子I阴性菌株对复方新诺明耐药性差异有统计学意义。85株嗜麦芽窄食单胞菌12株整合酶阳性,11株整合子I阳性,2株ISCR1和ISCRI携带的耐药基因阳性,ERIC-PCR分为75个基因型。结论整合子I在嗜麦芽窄食假单胞菌中介导复方新诺明耐药性方面有重要作用,ERIC-PCR是研究临床分离嗜麦芽窄食假单胞基因分型的有效方法之一。     

135株嗜麦芽寡养单胞菌的临床分布及耐药性分析

目的了解嗜麦芽寡养单胞菌的临床分布及耐药特征，为临床合理用药提供依据。方法用常规方法对2005—2008年本院临床标本进行细菌的培养、分离，用MicWalK40进行细菌的鉴定，以美国临床实验室标准化研究所推荐的纸片扩散法（K—B法）进行药物敏感性试验，Whonet 5．0进行数据统计。结果135株嗜麦芽寡养单胞菌主要来自痰占76．3％（103／135），分布以重症监护室（ICU）为主占80．0％（108／135）；对6种抗菌药物的敏感率分别为替卡西林／棒酸36．3％、氯霉素57．8％、头孢他啶64．4％、左氧氟沙星75．6％、复方新诺明77．0％及米诺环素100．0％。结论临床分离的嗜麦芽寡养单胞菌主要来自痰标本，分布以ICU为主，米诺环素、复方新诺明、左氧氟沙星、头孢他啶对嗜麦芽寡养单胞菌具有较好的体外抗菌活性。     

氟喹诺酮类药物对嗜麦芽窄食单胞菌的抗菌活性及CCCP对其的影响

目的 :了解氟喹诺酮类药物 (FQNS)对嗜麦芽窄食单胞菌的抗菌活性及氰氯苯腙 (CCCP)对其抗菌活性的影响。方法 :采用琼脂二倍稀释法测定抗菌药物的最低抑菌浓度 (MIC) ,同时测定CCCP对FQNS的MIC值的影响。结果 :1 4 4株嗜麦芽窄食单胞菌对多种常用抗生素呈现多重耐药 ,但对复方新诺明、替卡西林 /克拉维酸以及FQNS的耐药率较低 ,尤其是新型FQNS具有很高的抗菌活性 ,其中抗菌活性由高到低依次是加替沙星、司帕沙星、左氧氟沙星和环丙沙星。主动外排泵抑制剂CCCP在体外能增强FQNS的抗菌活性 ,主动外排机制不仅存在于FQNS耐药…     

396株嗜麦芽窄食单胞菌的耐药特征研究

目的研究嗜麦芽窄食单胞菌的耐药特征。方法采用美国临床实验室标准化委员会（ＮＣＣＬＳ）推荐的纸片扩散法,测定了５年中初次分离的３９６株嗜麦芽窄食单胞菌对ＴＭＰ－ＳＭＺ,多西环素,替卡西林－克拉维酸等２０种抗生素的耐药特征,并对１０例嗜麦芽窄食单胞菌菌血症的治疗进行了分析。结果嗜麦芽窄食单胞菌对ＴＭＰ－ＳＭＺ,替卡西林－克拉维酸,多西环素,环丙沙星和头孢他啶的敏感率最高,分别为８１．０％,９１．０％,９６．０％,７０．７％和５３．８％,而对氨苄西林,氨苄西林－舒巴坦,阿莫西林－克拉维酸,头孢唑林,头孢克罗,头孢美唑,头孢呋辛,头孢噻肟,头孢曲松,氨曲南,亚胺培南高水平耐药,敏感率为（０．９～７．５）％。从替卡西林－克拉维酸,多西环素,ＴＭＰ－ＳＭＺ,环丙沙星和头孢他啶对嗜麦芽窄食单胞菌抑菌环直径分布累积百分率图看出：替卡西林－克拉维酸,多西环素,ＴＭＰ－ＳＭＺ和环丙沙星为活性最好的抗生素。结论替卡西林－克拉维酸,ＴＭＰ－ＳＭＺ和多西环素对所研究的嗜麦芽窄食单胞菌有较高的活性,系嗜麦芽窄食单胞菌菌血症严重感染治疗最有效的抗生素     

嗜麦芽窄食单胞菌临床株的多重耐药外排泵的研究

目的　研究嗜麦芽窄食单胞菌临床株外排泵SmeDEF的表达与耐药的关系及其表达调控。方法　琼脂稀释法检测嗜麦芽窄食单胞菌对抗生素敏感性并检测泵抑制剂的作用 ,提取临床菌的RNA进行smeD的RT PCR扩增。提取DNA进行smeT片段的PCR扩增 ,扩增产物进行序列分析。结果　随机选取的 6株嗜麦芽窄食单胞菌均有扩增产物。SmeT的N端氨基酸序列相当保守 ,smeD smeT间区测序发现耐药且泵抑制阳性株基因序列与敏感株明显不同。推测与耐药有关的突变出现在smeT的 82～ 16 5区间。结论　嗜麦芽窄食单胞菌临床株SmeDEF外排泵的表达强弱与其耐药性有关。smeDEF基因的表达可能与调控基因间区的变化有关。     

848株革兰阴性杆菌的临床分布及耐药性分析

目的 了解近年临床分离的革兰阴性杆菌分布及耐药性特征.方法 收集2007年11月～2009年9月临床各类标本中分离的革兰阴性杆菌848株,采用VITEK2全自动细菌鉴定仪进行细菌鉴定及药物敏感实验,用SPSS软件完成数据分析.结果 2007年11月～2009年9月共收集848株革兰阴性杆菌,以大肠埃希菌、肺炎克雷伯菌、铜绿假单胞菌、不动杆菌、阴沟肠杆菌最多见,哌拉西林、环丙沙星、左氧氟沙星、庆大霉素、复方新诺明对大肠埃希菌的MIC90分别为256,8,16,32,640ug/ml.头孢曲松、头孢泊肟、环丙沙星对铜绿假单胞菌的MIC90分别为128,16,8 ug/ml,有较高的耐药性,嗜麦芽窄食单胞菌对所监测的抗生素广谱耐药.结论 临床细菌耐药性日趋严重,有效的进行耐药监测,统计和分析,对强调临床合理应用抗生素有重要的指导意义.     

371株鲍曼不动杆菌的临床耐药状况

本文对临床分离出的鲍曼不动杆菌的耐药性进行回顾性分析,为临床经验性治疗首选抗生素提供依据。对我院2006年10月至2009年10月分离出的371株鲍曼不动杆菌,用VITEK32细菌鉴定及药敏分析系统进行细菌鉴定和药敏试验,结合K-B法作补充对照。在分离出的371株鲍曼不动杆菌中,以老年煤工尘肺患者及重症监护病人集中的科室比率较高,在呼吸道标本中的构成比高于其他种类的标本。该菌对亚胺培南、哌拉西林/他唑巴坦,氨苄西林/舒巴坦的耐药率相对较低,各为5.0%、19.5%、19.5%。对复方新诺明、妥布霉素、左氧氟沙星、庆大霉素、环丙沙星、头孢吡肟、头孢他啶的耐药率分别为32.7%、43.2%、44.6%、44.9%、47.3%、53.8%、56.5%。对头孢曲松、氨曲南、氨苄西林、呋喃妥因、头孢唑啉有较高的耐药性,耐药率均在90%以上。鲍曼不动杆菌对多种抗生素耐药现象严重,根据药敏试验合理应用抗生素十分重要。     

某医院ICU与普通病房肺炎克雷伯菌耐药性对比分析

目的 分析某医院ICU与普通病房肺炎克雷伯菌感染的临床分布及耐药性差异,为临床合理使用抗菌药物提供科学依据.方法 采用VITEK-2 Compact全自动微生物鉴定及药敏分析系统对本院2020年临床分离的肺炎克雷伯菌进行鉴定及药敏实验,比较分析ICU与普通病房肺炎克雷伯菌耐药性差异.结果 ICU与普通病房送检标本均以痰标本为主,分别占74.1％、67.1％.全院检出的肺炎克雷伯菌对氨苄西林/舒巴坦、头孢曲松、呋喃妥因具有较高的耐药性,耐药率分别达57.4％、53.6％、51.5％,对碳青霉烯类抗生素保持较高的敏感性,敏感率均在70％以上.ICU检出的肺炎克雷伯菌对呋喃妥因的耐药率最高,高达92.3％,对氨苄西林/舒巴坦、氨曲南、复方新诺明、环丙沙星、头孢吡肟、头孢曲松、头孢他啶的耐药率也高达50％以上;普通病房检出的肺炎克雷伯菌对呋喃妥因的耐药率达87％,对氨苄西林/舒巴坦、头孢曲松的耐药率分别为59.4％、51.6％.ICU检出的肺炎克雷伯菌对被检的18种抗生素中,除阿米卡星、庆大霉素外,其余抗生素的耐药率均高于普通病房,差异具有统计学意义(P<0.05).结论 ICU检出的肺炎克雷伯菌的耐药率高于普通病房,应引起临床高度重视;抗感染过程中,应根据药敏结果合理选择抗菌药物.     

新生儿病房呼吸机相关性肺炎病原菌变迁及药物敏感性分析

目的探讨近年新生儿层流病房应用后新生儿呼吸机相关性肺炎（VAP）的病原菌变迁及药物敏感性情况。方法系统回顾我院新生儿重症监护病房（NICU）近4年接受机械通气〉48h的287例患儿的I临床资料,以发生时间先后分成两组,分析其VAP发病情况、痰培养病原学、药敏结果及治疗转归等。结果近4年NICU的VAP发生率为15．68％．培养出致病菌株共32株．依次为缓症链球菌、嗜麦芽窄食单胞菌、溶血葡萄球菌、肺炎克雷伯菌等。前两年病原菌以革兰阳性菌为主,主要是缓症链球菌和葡萄球菌属,近两年以革兰阴性杆菌为主,尤以嗜麦芽窄食单胞菌居多。以万古霉素、环丙沙星、氧氟沙星为主要敏感药物,对青霉素类抗生素及第二、三代头孢菌素普遍耐药。结论近年VAP致病菌谱发生显著改变,以耐药性条件致病菌为主,强调综合治疗,预防为主,尽早使用敏感药物。     

Stenotrophomonas maltophilia in the respiratory tract of medical intensive care unit patients

The purpose of this study was to investigate characteristics of critically ill patients with Stenotrophomonas maltophilia (S. maltophilia) isolated from the respiratory tract, to identify risk factors for S. maltophilia-pneumonia and intensive care unit (ICU) mortality and to analyze antibiotic susceptibility of S. maltophilia. This was a retrospective analysis of 64 medical ICU patients with S. maltophilia in the respiratory tract. Thirty-six patients fulfilled the criteria for diagnosis of pneumonia. A significantly higher lung injury score (LIS) was observed in patients with pneumonia compared to patients with colonization (p=0.010). Independent risk factors for S. maltophilia-pneumonia were higher Sequential Organ Failure Assessment (SOFA) score (p=0.009) and immunosuppression (p=0.014). Patients with S. maltophilia-pneumonia had higher ICU mortality within a 28-day follow-up (p=0.040) and higher hospital mortality (p=0.018) than patients with colonization. The highest antibiotic susceptibility rates were observed to trimethoprim-sulfamethoxazole, tigecycline, and moxifloxacin. Higher SOFA score when S. maltophilia was isolated (p=0.001) and development of renal failure (p=0.021) were independent risk factors for ICU mortality. Higher SOFA score and immunosuppression are independent risk factors for S. maltophilia-pneumonia. Patients with S. maltophilia-pneumonia have a significantly higher ICU mortality within a 28-day follow-up, hospital mortality and LIS compared to patients with S. maltophilia-colonization.     

儿童呼吸内科下呼吸道分离菌分布及药敏分析

目的 分析我院儿童呼吸内科下呼吸道标本分离菌的分布及其耐药情况,为临床治疗用药提供参考。方法 对我院2016年7月~2018年6月呼吸内科送检的4137例下呼吸道标本分离菌进行收集,并进行药敏试验。结果 4317例送检标本中共分离出2060株（去除重复菌株）,其中革兰阴性菌1437株,占69.75%;革兰阳性菌623株,占30.25%。排前五的分离菌依次为流感嗜血杆菌（41.02%）、肺炎链球菌（21.17%）、卡他莫拉菌（19.03%）、金黄色葡萄球菌（8.98%）、肺炎克雷伯菌（3.83%）。流感嗜血杆菌、卡他莫拉菌对头孢噻肟、利福平、氧费沙星全部敏感;对氨苄西林、复方新诺明敏感性低。肺炎链球菌、金黄色葡萄球菌对利奈唑胺、万古霉素全部敏感;对红霉素敏感性低。结论 儿童下呼吸道病原菌种类多样,主要为革兰阴性菌,应依据病原菌的种类及药敏特点选择有针对性的高效抗菌药物,制定个体化治疗方案,减少耐药菌株的产生。     

2016~2018年鲍曼不动杆菌临床分离株的 分布特征及耐药性变迁

目的 了解鲍曼不动杆菌在我院的分布特征及耐药性变迁,为临床合理选用抗菌药物提供依据。方法 采用珠海迪尔DL-96Ⅱ微生物分析仪进行细菌鉴定与药敏试验,对我院2016年1月~2018年12月临床各类标本中分离出的鲍曼不动杆菌的分布特征及耐药情况进行分析。结果 分离出551株鲍曼不动杆菌,年分离率相对稳定,但多重耐药鲍曼不动杆菌构成比上升明显,从67.28%上升到了82.21%。鲍曼不动杆菌主要分离自痰及咽拭子标本,占67.69%;感染主要发生在ICU病房、呼吸科和神经内科,其次为内分泌科和老干科。临床常用13种抗菌药物的耐药率与2016年比较,多种抗菌药物耐药率上升显著;2018年与2017年比较,耐药情况控制较好,其中米诺环素和多粘菌素B耐药率最低,分别为14.90%和16.35%;其余耐药率均大于55%。结论 鲍曼不动杆菌在我院耐药情况比较严重,对多种抗菌药物耐药率都达到了较高水平,临床应根据药敏结果和临床实际合理选用抗菌药物。     

Antimicrobial susceptibility of Stenotrophomonas maltophilia isolates from a Korean tertiary care hospital

We determined the antimicrobial susceptibility of 90 clinical isolates of Stenotrophomonas maltophilia collected in 2009 at a tertiary care hospital in Korea. Trimethoprim-sulfamethoxazole, minocycline, and levofloxacin were active against most of the isolates tested. Moxifloxacin and tigecycline were also active and hold promise as therapeutic options for S. maltophilia infections.     

Stenotrophomonas maltophilia bacteremia in adults: four years' experience in a medical center in northern Taiwan.

Stenotrophomonas maltophilia has become an important nosocomial pathogen in immunocompromised patients in Taiwan. Patients with underlying diseases such as diabetes, uremia, and solid malignancy are extremely vulnerable to this organism. S. maltophilia bacteremia has a mortality rate of up to 62% if appropriate antibiotics are not instituted early. Knowledge of the risk factors for infection as well as local susceptibility patterns is helpful in determining which patients should receive empirical antibiotics active against S. maltophilia. This study assessed the characteristics of 50 episodes of S. maltophilia bacteremia in 48 patients admitted between March 3, 1999 and May 21, 2003. The new fluoroquinolone levofloxacin showed promising in vitro activity against S. maltophilia in view of the increasing resistance of isolates to trimethoprim-sulfamethoxazole. For patients at risk for S. maltophilia infection, such as those receiving mechanical ventilation in the ICU or those with multiple vascular access devices, the need for antimicrobial agents to which S. maltophilia is normally sensitive should be considered in selecting empiric therapy.     

Role of Stenotrophomonas maltophilia in hospital-acquired infection

Stenotrophomonas maltophilia (previously Pseudomonas maltophilia, Xanthomonas maltophilia) is highly resistant to antibiotics. It causes infections that result in increased morbidity, but not usually mortality, in patients with weakened host defences. The increase in S. maltophilia nosocomial infections is due to the changing nature of the hospital patient population and to changes in antibiotic usage. Detection, identification and susceptibility testing methods require improvement, and this complicates the comparison of published data. Susceptibility testing should be reserved for those isolates that are clearly associated with disease. Treatment can be difficult and may be complicated by biofilm formation. S. maltophilia can both acquire and transfer resistance to antibiotics. Future therapeutic development may be directed against biofilms and efflux mechanisms, in order to render the organism more susceptible to available antimicrobial agents.     

Evaluation of the VITEK 2 system for the identification and susceptibility testing of three species of nonfermenting gram-negative rods frequently isolated from clinical samples

VITEK 2 is a new automatic system for the identification and susceptibility testing of the most clinically important bacteria. In the present study 198 clinical isolates, including Pseudomonas aeruginosa (n = 146), Acinetobacter baumannii (n = 25), and Stenotrophomonas maltophilia (n = 27) were evaluated. Reference susceptibility testing of cefepime, cefotaxime, ceftazidime, ciprofloxacin, gentamicin, imipenem, meropenem, piperacillin, tobramycin, levofloxacin (only for P. aeruginosa), co-trimoxazole (only for S. maltophilia), and ampicillin-sulbactam and tetracycline (only for A. baumannii) was performed by microdilution (NCCLS guidelines). The VITEK 2 system correctly identified 91.6, 100, and 76% of P. aeruginosa, S. maltophilia, and A. baumannii isolates, respectively, within 3 h. The respective percentages of essential agreement (to within 1 twofold dilution) for P. aeruginosa and A. baumannii were 89.0 and 88.0% (cefepime), 91.1 and 100% (cefotaxime), 95.2 and 96.0% (ceftazidime), 98.6 and 100% (ciprofloxacin), 88.4 and 100% (gentamicin), 87.0 and 92.0% (imipenem), 85.0 and 88.0% (meropenem), 84.2 and 96.0% (piperacillin), and 97.3 and 80% (tobramycin). The essential agreement for levofloxacin against P. aeruginosa was 86.3%. The percentages of essential agreement for ampicillin-sulbactam and tetracycline against A. baumannii were 88.0 and 100%, respectively. Very major errors for P. aeruginosa (resistant by the reference method, susceptible with the VITEK 2 system [resistant to susceptible]) were noted for cefepime (0.7%), cefotaxime (0.7%), gentamicin (0.7%), imipenem (1.4%), levofloxacin (2.7%), and piperacillin (2.7%) and, for one strain of A. baumannii, for imipenem. Major errors (susceptible to resistant) were noted only for P. aeruginosa and cefepime (2.0%), ceftazidime (0.7%), and piperacillin (3.4%). Minor errors ranged from 0.0% for piperacillin to 22.6% for cefotaxime against P. aeruginosa and from 0.0% for piperacillin and ciprofloxacin to 20.0% for cefepime against A. baumannii. The VITEK 2 system provided co-trimoxazole MICs only for S. maltophilia; no very major or major errors were obtained for co-trimoxazole against this species. It is concluded that the VITEK 2 system allows the rapid identification of S. maltophilia and most P. aeruginosa and A. baumannii isolates. The VITEK 2 system can perform reliable susceptibility testing of many of the antimicrobial agents used against P. aeruginosa and A. baumannii. It would be desirable if new versions of the VITEK 2 software were able to determine MICs and the corresponding clinical categories of agents active against S. maltophilia.     

Microbiological and Clinical Aspects of Infection Associated with Stenotrophomonas maltophilia

The gram-negative bacterium Stenotrophomonas maltophilia is increasingly recognized as an important cause of nosocomial infection. Infection occurs principally, but not exclusively, in debilitated and immunosuppressed individuals. Management of S. maltophilia-associated infection is problematic because many strains of the bacterium manifest resistance to multiple antibiotics. These difficulties are compounded by methodological problems in in vitro susceptibility testing for which there are, as yet, no formal guidelines. Despite its acknowledged importance as a nosocomial pathogen, little is known of the epidemiology of S. maltophilia, and although it is considered an environmental bacterium, its sources and reservoirs are often not readily apparent. Molecular typing systems may contribute to our knowledge of the epidemiology of S. maltophilia infection, thus allowing the development of strategies to interrupt the transmission of the bacterium in the hospital setting. Even less is known of pathogenic mechanisms and putative virulence factors involved in the natural history of S. maltophilia infection and this, coupled with difficulties in distinguishing colonization from true infection, has fostered the view that the bacterium is essentially nonpathogenic. This article aims to review the current taxonomic status of S. maltophilia, and it discusses the laboratory identification of the bacterium. The epidemiology of the organism is considered with particular reference to nosocomial outbreaks, several of which have been investigated by molecular typing techniques. Risk factors for acquisition of the bacterium are also reviewed, and the ever-expanding spectrum of clinical syndromes associated with S. maltophilia is surveyed. Antimicrobial resistance mechanisms, pitfalls in in vitro susceptibility testing, and therapy of S. maltophilia infections are also discussed.     

2016~2018年某院ICU 医院感染目标性监测及干预

目的 分析我院ICU医院感染现状,为医院感染管理提供依据。方法 制定ICU医院感染目标性监测方案,采用前瞻性监测方法对我院2016~2018年ICU患者进行目标性监测,每季度根据监测结果进行实时干预。结果 通过监测及干预,连续三年ICU医院感染发病率、医院感染例次发病率、日感染发病率、调整医院感染发病率、调整医院感染例次发病率以及调整日感染发病率均呈逐年下降趋势（P＜0.05）。神经系统和呼吸系统疾病类ICU住院患者的医院感染发病率分别为10.83%、3.31%。ICU医院感染部位以呼吸道为主,占70.67%。呼吸机、导尿管、中心静脉导管的使用率分别为33.90%、71.92%、22.73%,三管相关发病率分别为10.00‰、1.49‰、1.81‰。呼吸机使用率与VAP发病率有相关性（r=1.00,P＜0.001）。医院感染前3位病原菌分别为肺炎克雷伯菌（占30.23%）、鲍曼不动杆菌（占23.26%）、铜绿假单胞菌（占10.47%）。结论 持续开展ICU医院感染目标性监测,有利于针对高危因素及薄弱环节及时采取干预措施,从而有效降低医院感染发病率。神经系统疾病类和呼吸系统疾病类患者是院感防控关注的重点人群,器械相关性感染（特别是VAP）、多重耐药菌感染是干预的重点环节。