Molecular Detection of Carbapenemase Genes in Extensive Drug Resistant Acinetobacter baumannii Clinical Isolates from ICU Patients, Khartoum

Background: The emergence of carbapenemase producing Acinetobacter baumannii is increasingly reported nowadays and constitutes a major problem to the intensive care unit (ICU) patients with notable extensive-drug resistance ability. The study investigates carbapenemase producing A. baumannii strains exhibiting an extensively drug-resistant (XDR) phenotype, isolated from ICU patients in Khartoum. Methods: A total of 100 nonduplicate Gram-negative coccobacilli strains were obtained from microbiology laboratory of ICU patients’ clinical isolates. Molecular identification of A. baumannii was performed by targeting 16S rRNA gene using specifically designed primers. Then, XDR strains were determined by susceptibility testing (disc diffusion). For detection of carbapenemase genes Polymerase chain reaction (PCR) was carried out. Result: Of 100 ICU clinical isolates, 38 (38.0%) was confirmed A. baumannii strains, those strains showed 100% carbapenem resistance and 60.5% extensive drug resistance to the antibiotics tested. The frequency of carbapenemase producer was 57.9% (22/38) of carbapenem resistance A. baumannii (CRAB). The most common carbapenemase associated with resistance was blaOXA gene followed by blaNDM and blaGES A. baumannii isolates. The co-occurrence of blaOXA-48-like and blaNDM, blaOXA-23-like and blaOXA-51, and blaNDM-1 and blaOXA-51 was detected in 22.7%, 18.2% strains and 4.5% respectively. A unique characteristic of our findings was the coharbouring of the genes blaNDM-1, blaOXA-23-like, blaOXA-51 and blaOXA-143 in 9.1% strains (2/22), and this was the first report in the Khartoum city, Sudan. Conclusion: We have demonstrated for the first time a high prevalence of XDR-carbapenemase producing A. baumannii clinical isolates from ICU patients in Khartoum. Also an emergent blaOXA-143 was reported as High-Risk Clones. This highlights the routine mentoring of XDR-carbapenemase producing A. baumannii to avoid clone dissemination in our region hospitals.

An Extensively Drug Resistant Acinetobacter baumannii from Soft Tissue Isolated in a Hospital in Senegal

Emerging and rapidly spreading multidrug resistant bacteria constitute a rising public health concern worldwide. Acinetobacter baumannii is one of these bacteria that cause different infections including pneumonia, bacteremia, meningitis, soft-tissue, and urinary tract infections, and are associated with high mortality and economic burden. We present a case of a 43-year-old woman, admitted at the department of orthopedics, regional hospital of Ourossogui, North-East of Senegal for soft-tissue injuries. Initially diagnosed with Yersinia pestis infection, the patient was well managed before being released. Supplementary sampling for confirmatory tests allowed the detection of an extensively drug-resistant Acinetobacter baumannii clone.

Antibacterial resistance patterns of Acinetobacter baumannii complex:The results of Isfahan Antimicrobial Resistance Surveillance-1 Program

Objective: To determine the antibiotic resistance patterns of the Acinetobacter(A.) baumannii complex isolates that cause the confirmed infection. Methods: The present descriptive study was performed from March 2016 to March 2018 in three referral hospitals in Isfahan, Iran. All A. baumannii complex strains isolated from different clinical samples were identified by conventional phenotypic methods and antibiotic susceptibility pattern was detected. After the clinical investigation, contaminated samples were excluded and the source(hospital/community) and site of the infection were determined. Data on antibiotic susceptibility testing were extracted from WHONET software and analysis was done with SPSS.Results: From 254 patients who had confirmed A. baumannii complex infection, 158(62.20%) cases were male, 27(10.63%) were less than 20 years old, 172(67.72%) had healthcare-associated infections and 96(37.79%) were admitted in intensive care units. The most frequent infection was bloodstream infections(111, 43.70%). Our results showed that most of the isolates were resistant to most of the antibiotics(more than 75.00%) and a lower rate of non-susceptibility was observed against minocycline(20, 44.44%) and colistin(0%). The rate of multidrug-resistant isolates was 88.97%. There was no significant difference between resistance of A. baumannii complex isolates according to age. However, the resistance to amikacin and minocycline and the rate of multidrug resistance(MDR) were significantly different between males and females. In patients with healthcare associated infection(HAI), MDR isolates were significantly different regarding admission in ICU ward. Resistance to levofloxacin and ciprofloxacin were lower in isolates from patients with bloodstream infections in comparison to other diagnoses.Conclusions: In our study, a high level of antibiotic resistance was detected in both community-acquired and healthcare-associated A. baumannii complex infections. Appropriate antibiotic prescription in a clinical setting is an essential need for the control and prevention of A. baumannii resistant infections.

Risk factors and outcomes of imipenem-resistant Acinetobacter bloodstream infection in North-eastern Malaysia

Objective:To determine the risk factors and outcomes of imipenem-resistant Acinetobacter baumannii(IRAB) bloodstream infection(BSI) cases,since there is very little publication on Aeinetobacter baumannii infections from Malaysia.Methods:A cross sectional study of 41 cases(73.2%) of imipenem-sensitive Acinetobacter baumanii(ISAB) and 15 cases(26.8%) of IRAB was conducted in a teaching hospital which was located at North-Eastern state of Malaysia.Results:There was no independent risk factor for IRAB BSI identified but IRAB BSI was significantly associated with longer bacteraemic days[OR 1.23(95%CI 1.01,1.50)].Although prior use of carbepenems and cephalosporin were higher among IRAB than ISAB group,statistically they were not significant.There was no significant difference in term of outcomes between the two groups.Conclusions:Although statistically not significant,this analysis compliments previous publication highlighting the importance of appropriate empiric antibiotic usage in hospital especially carbepenems and need further evaluation with bigger subjects.

Clinical Distribution and Drug Resistance of Acinetobacter baumannii in a Hospital from 2019 to 2021

Objective:To analyze the clinical distribution and drug resistance of Acinetobacter baumannii(AB)and provide reference for the treatment of AB infection.Methods:AB isolated from clinical specimens of Huaihua First People’s Hospital from 2019 to 2021 were collected and identified by VITEK 2 Compact,an automated microbial identification and susceptibility testing system,in which drug sensitivity test was also performed.Excel was used for statistical analysis.Results:Among the 1,311 AB strains,81.16%(1,064 strains)were from sputum samples,and the departments with the highest detections rates of AB were neurosurgery(24.33%),intensive care(15.48%)and infectious disease(11.44%).The drug sensitivity test showed that the resistance rate of 1,311 AB strains to compound sulfamethoxazole and amikacin was 28.38%and 20.54%,respectively,and the resistance rate to 10 other kinds of common antibiotics was more than 40%.Conclusion:The 1,311 AB strains isolated were widely distributed in clinical settings and had strong resistance to commonly used antibiotics.Therefore,it is necessary to strengthen the monitoring of pathogens and drug resistance,formulate reasonable and effective infection control measures,and ensure that antibiotics are used in a reasonable manner.

中药在控制耐药菌Acinetobacter baumannii繁殖中的研究进展

鲍曼不动杆菌存在多重耐药性,感染后可选择抗菌药物有限,病死率高,抗鲍曼不动杆菌感染是目前临床研究领域的重点和难点。部分中药表现出抑制鲍曼不动杆菌生长的作用,但是其抗菌机制尚不清楚。基于此,本文系统综述了近年来中草药在控制鲍曼不动杆菌感染方面的研究进展,以期为中药抗菌药物的研发提供依据。

Multi Drug Resistance Bacterial Isolates of Surgical Site Infection

Multi drug resistance microorganism is considered to be one of the major health problems. The aim of this study was to determine antibiotic susceptibility pattern of bacterial pathogens of surgical site infection. A total 250 samples were included, out of which 62.4% showed significant bacterial growth. Gram negative bacteria were 85.25% and gram positive bacteria were 14.75%;among them 65.38% of the total isolates were multi drug resistance (MDR). The age group between 31 - 40 found the highest number of isolates 22.4%. Among gram negative bacilli, the highest production of MDR was found in Acinetobacter spp. followed by Pseudomonas aeruginosa, Klebsiella pneumoniae and Escherichia coli. In gram positive cocci, the highest production of MDR was found in Staphylococcus aureus. Acinetobacter spp. was found highly susceptible to amikacin and gentamycin 20.1% followed by ofloxacin and ciprofloxacin 18.6% and 16.2% respectively. Staphylococcus aureus showed 100% sensitive to clindamycin whereas penicillin showed 100% resistance followed by amoxycillin (93.75%). Amikacine and clindamycin were drugs of choice for gram negative and gram positive bacteria respectively. This study showed that alarming increase of infections was caused by multi drug resistance bacterial organisms. It increases length of stay and may produce lasting sequelae and requires extra resources for investigations, management and nursing care. Surveillance of surgical site infection is a useful tool to demonstrate the magnitude of the problem and find out appropriate preventive methods.

Drug-resistant gene based genotyping for Acinetobacter baumannii in tracing epidemiological events and for clinical treatment within nosocomial settings

Background Acinetobacter baumannfi has emerged as an important pathogen related to serious infections and nosocomial outbreaks around the world. However, of the frequently used methods, pulsed-field gel electrophoresis （PFGE） and amplified fragment length polymorphism （AFLP） in Acinetobacter baumannfi genotyping lack the direct molecular proof of drug resistance. This study was conducted to establish a typing method based on drug resistant gene identification in contrast to traditional PFGE and AFLP in the period of nosocomial epidemic or outbreak. Methods From January 2005 to October 2005, twenty-seven strains of Acinetobacter species from Intensive Care Units, the Second Affiliated Hospital in Ningbo were isolated, including both epidemic and sporadic events. Susceptibility test, PFGE, AFLP and drug resistance gene typing （DRGT） were carried out to confirm the drug resistance and analyze the genotyping, respectively. PFGE was used as a reference to evaluate the typeability of DRGT and AFLP. Results Twenty-seven strains of Acinetobacter displayed multiple antibiotic resistance and drug resistant genes, and β-1actamase genes were detected in 85.2% strains. The result of DRGT was comparable to PFGE in Acinetobacter strains with different drug resistance though a little difference existed, and even suggested a molecular evolution course of different drug-resistant strains. AFLP showed great polymorphism between strains and had weak ability in distinguishing the drug resistance. Conclusion Compared to AFLP and PFGE, DRGT is useful to analyze localized molecular epidemiology of nosocomial infections and outbreaks, which would benefit clinical diagnosis and therapy.

Trends in Drug Resistance of Acinetobacter baumannii over a 10-year Period： Nationwide Data from the China Surveillance of Antimicrobial Resistance Program

Background： Acinetobacter baumannii has emerged as an important pathogen causing a variety of infections. Using data from the China Surveillance of Antimicrobial Resistance Program conducted biennially, we investigated the secular changes in the resistance of 2917 isolates ofA. baumannii from 2004 to 2014 to differ antimicrobial agents. Methods： Pathogen samples were collected from 17 to 20 hospitals located in the eastern, central, and western regions of China. Minimum inhibitory concentrations （MICs） were determined by a 2-fold agar dilution method, and antimicrobial susceptibility was established using the 2014 Clinical Laboratory Standards Institute-approved breakpoints. Isolates not susceptible to all the tested aminoglycosides, fluoroquinolones, β-lactams, β-lactam/β-lactam inhibitors and carbapenems were defined as extensively drug resistant. Results： The rates of nonsusceptibility to common antimicrobial agents remained high （〉65%） over the years with some fluctuations to certain agents. The prevalence of imipenem-resistant A. batmlannii （IRAB） increased from 13.3% in 2004 to 70.5% in 2014 and that of extensively drug-resistant A. haumannii （XDRAB） increased from I1.1% in 2004 to 60.4% in 2014. The activity of tigecycline was stable with MIC,≤4 mg/L against A. baumannii from 2009 to 2014. Susceptibility to colistin remained high （97.0%） from 2009 to 2014. The prevalence of XDRAB increased in all the three surveillance regions over the years and was significantly higher in Intensive Care Unit （ICU） wards than non-lCU wards. Conclusions： This longitudinal multicenter surveillance program revealed the nationwide emergence of A. baumnnii in China and showed a significant increase in prevalence from 2004 to 2014. High levels of bacterial resistance were detected among samples collected from clinical settings in China, with IRAB and XDRAB being especially prevalent. This study will help to guide empirical therapy and identify at-risk groups requiring more intense interventional infection control measures, while also helping to focus surveillance efforts.

鲍曼不动杆菌外膜蛋白33-36的研究进展

鲍曼不动杆菌(acinetobacter baumannii,AB)是院内感染常见的不动杆菌之一,尤其在重症监护病房,常导致患者临床结局恶化,增加患者经济负担。目前对于AB的研究主要集中于致病机制、耐药性等方面,其中外膜蛋白33-36作为重要的致病因子,一直是研究热点。本文将从AB外膜蛋白33-36的致病机制、耐药性方面总结外膜蛋白33-36的研究进展。

某三甲医院2017-2022年常见G^(-)菌的分布及耐药性分析

目的 分析2017-2019年和2020-2022年我院革兰阴性(G^(-))菌的病原菌分布、细菌耐药情况,为临床合理地应用抗菌药物提供参考依据。方法 采用回顾性分析2017-2019年和2020-2022年我院的各类送检标本,采用专业认可的鉴定系统或手工方法进行细菌鉴定和耐药性检测,应用Whonet5.6软件进行数据分析。结果 共检出革兰阴性菌14421株,痰液标本最常见。2017-2019年我院分离的G^(-)菌居前5位者为大肠埃希菌、肺炎克雷伯菌、鲍曼不动杆菌、铜绿假单胞菌、阴沟肠杆菌。2020-2022年我院分离的G^(-)菌居前5位者为肺炎克雷伯菌、大肠埃希菌、鲍曼不动杆菌、铜绿假单胞菌、阴沟肠杆菌。两组主要标本来源均为痰、尿液和分泌物。2020-2022年和2017-2019年相比,大肠埃希菌和肺炎克雷伯菌对多数抗生素的耐药率呈下降趋势(P<0.05);肺炎克雷伯菌对环丙沙星的耐药率呈上升趋势(χ^(2)=6.045,P<0.05);2020-2022年和2017-2019年相比,鲍曼不动杆菌对左氧氟沙星耐药率呈上升趋势(χ^(2)=18.328,P<0.05),对氨基糖苷类庆大霉素和妥布霉素耐药率呈下降趋势(χ^(2)=46.647,χ^(2)=31.780,P均<0.05);铜绿假单胞菌对头孢他啶、喹诺酮类环丙沙星和左氧氟沙星耐药率呈上升趋势(χ^(2)=8.201,χ^(2)=4.298,χ^(2)=15.032,P均<0.05),对β-内酰胺类亚胺培南和美罗培南耐药率呈下降趋势(χ^(2)=26.089,χ^(2)=24.966,P均<0.05);阴沟肠杆菌对头孢呋辛钠耐药率呈下降趋势(χ^(2)=121.541,P<0.05)。结论 2020-2022年和2017-2019年相比,我院部分G^(-)菌对一些抗菌药物的耐药率有所下降,但总体G^(-)菌的耐药形势仍然十分严峻,需定期进行细菌耐药性监测。

Relationship between antimicrobial resistance and aminoglycoside-modifying enzyme gene expressions in Acinetobacter baumannii

Background Acinetobacter baumannii is one of the main gramnegative bacilli in clinical practice Nosocomial infections caused by multidrug resistance Acinetobacter baumannii is very difficult to treat This study was designed to investigate the antimicrobial resistance characteristics and four resistant gene expressions of aminoglycosidemodifying enzymes including Nacetyltransferases and Ophosphotransferases in Acinetobacter baumannii Methods Bacterial identification and antimicrobial susceptibility test were performed by PhoenixTM system in 247 strains of Acinetobacter baumannii Minimal inhibitory concentrations (MICs) of seven aminoglycosides including gentamicin, amikacin, kanamycin, tobramycin, netilmicin, neomycin and streptomycin in 15 strains of multidrug resistant Acinetobacter baumannii were detected by agar dilution Four aminoglycosidemodifying enzyme genes were amplified by polymerase chain reaction (PCR) and verified by DNA sequencerResults The resistance rates of 247 strains of Acinetobacter baumannii against cefotaxime, levofloxacin, piperacillin, aztreonam, tetracycline, ciprofloxacin and chloramphenicol were more than 50% Imipenem and meropenem showed high antibacterial activities with resistance rates of 32% and 41% MIC50 and MIC90 of gentamicin, amikacin, streptomycin and kanamycin in 15 strains of multidrug resistant Acinetobacter baumanii were all more than 1024 mg/L, and the resistance rates were 100%, 100%, 100% and 933%, respectively But their resistance rates to tobramycin, netilmicin and neomycin were 867%, 933% and 467%, respectively Three modifying enzyme genes, including aacC1, aacC2 and aacA4 genes, were found in 15 strains, but aphA6 had not been detected Their positive rates were 933%, 200% and 200%, respectively These three genes existed simultaneously in No19 strain Nucleotide sequences of aacC1, aacC2 and aacA4 genes shared 100%, 979% and 997% identities with GenBank genes (AY307113, S68058 and AY307114)Conclusion Multidrug resistant Acinetobacter baumannii strains are rapidly spreading in our hospital, and their resistance to aminoglycosides may be associated with aminoglycosidemodifying enzyme gene expressions

替加环素联合头孢哌酮/舒巴坦治疗多重耐药鲍曼不动杆菌肺炎的临床疗效

目的基于细菌清除率、炎症因子、安全性探究替加环素(TGC)联合头孢哌酮/舒巴坦(CPZ/SBT)治疗多重耐药鲍曼不动杆菌(MRAB)肺炎的作用。方法回顾性收集2022年1月至2023年6月期间在本院治疗的156例MRAB肺炎患者的临床资料,经1∶1倾向性评分匹配后,CPZ/SBT组50例和TGC+CPZ/SBT组各纳入50例。CPZ/SBT组给予头孢哌酮/舒巴坦治疗,TGC+CPZ/SBT组给予头孢哌酮/舒巴坦+替加环素治疗。检测并比较两组患者用药前后的痰液相关指标[嗜酸性粒细胞(Eos)和中性粒细胞(Neu)]、血清炎性标志物[白介素-6(IL-6)、C-反应蛋白(CRP)、肿瘤坏死因子-α(TNF-α)和降钙素原(PCT)],并对两组体征/症状改善时间、疗效总有效率、不良反应发生率、脱机成功率、细菌清除率、住院时间和28d死亡率进行比较,采用Spearman检验方法分析MRAB肺炎患者炎症相关指标与疗效总有效率之间的相关性。结果TGC+CPZ/SBT组患者体温变为正常、胸片阴影与肺部啰音消失、白细胞变为正常的时间相较于CPZ/SBT组明显缩短(P均<0.05)。TGC+CPZ/SBT组疗效总有效率以及细菌清除率显著高于CPZ/SBT组(94.00%vs 80.00%、90.00%vs 74.00%,P<0.05)。用药后,两组CRP、TNF-α、PCT、IL-6、Neu、Eos较用药前显著降低(P均<0.05),TGC+CPZ/SBT组CRP、TNF-α、PCT、IL-6、Neu、Eos明显低于CPZ/SBT组(P均<0.05)。TGC+CPZ/SBT组患者住院时间相较于CPZ/SBT组明显减少[(29.36±7.11)d vs(33.67±8.25)d,P<0.05],而TGC+CPZ/SBT组患者的脱机成功率较CPZ/SBT组明显提高(80.00%vs 60.00%,P<0.05),两组28d死亡率以及不良反应发生率差异无统计学意义(6.00%vs 16.00%,18.00%vs 10.00%,P均>0.05)。Spearman检验结果显示,治疗后血清CRP、TNF-α、PCT、IL-6及痰液Neu、Eos水平与TGC+CPZ/SBT组患者疗效总有效率呈负相关(r=-0.521、-0.425、-0.556、-0.463、-0.512、-0.488,P均<0.001)。结论MRAB肺炎患者采用替加环素联合CPZ/SBT治疗有助于提高疗效总有效率以及细菌清除率,降低体内炎症水平,安全性良好。

2006-2010年华西医院鲍曼不动杆菌的耐药趋势分析

目的了解临床分离的鲍曼不动杆菌的耐药性变迁,为临床合理用药提供依据。方法采用全自动微生物分析系统对分离出的6719株鲍曼不动杆菌进行药敏试验,收集数据统计分析。结果 ICU分离出的1611株鲍曼不动杆菌对14种常见抗菌药物的耐药率从2006-2010年呈逐年升高的趋势(P<0.05),非ICU科室分离出的5108株对10种常见抗菌药物的耐药率呈逐年升高的趋势(P<0.05),ICU和非ICU分离株对14种常见抗菌药物的5年总体耐药率有显著性差异(P<0.05)。结论加强抗生素的合理使用和规范管理是控制耐药率不断升高的有效手段。

1999～2003年鲍氏不动杆菌耐药变迁与β-内酰胺酶表型及基因型检测

目的了解5年来鲍氏不动杆菌的耐药性变迁、产β内酰胺酶(BLA)及BLA基因型存在状况。方法采用微量稀释法测定在1999年1月～2003年12月间,自临床分离的549株鲍氏不动杆菌对23种抗菌药物的敏感性、三维试验法检测超广谱β内酰胺酶(ESBLs)、AmpC酶、聚合酶链反应(PCR)及序列分析的方法分析BLA基因型。结果5年中总敏感率居前4位的依次是亚胺培南(96.4%)、多黏菌素E(93.0%)、美罗培南(92.9%)和哌拉西林/他唑巴坦(30.1%),其余在0.0～20.9%之间;5年间亚胺培南的抗菌活性最高,且历年不减,敏感率>95.0%;其次是多黏菌素E和美罗培南,敏感率分别>88.0%和84.0%;5年间耐药率上升最快的是阿莫西林/克拉维酸、头孢曲松、头孢噻肟、哌拉西林和哌拉西林/他唑巴坦;ESBLs及AmpC酶单独阳性率分别为30.0%和1.7%,48.3%菌株同时产ESBLs和AmpC两种酶;BLA基因TEM和SHV阳性率分别为100.0%和29.2%,基因型分别为TEM1、SHV12、SHV48和SHV56;OXA、CTXM、PER和VEB基因均阴性。结论近5年间鲍氏不动杆菌对大多数常用广谱抗生素的耐药性在逐年增强,并且多重耐药、产ESBLs及AmpC酶状况相当严重,BLA基因TEM和SHV携带率高;亚胺培南仍是抗多重耐药鲍氏不动杆菌感染最有效的抗生素。

多重耐药鲍曼不动杆菌β-内酰胺酶、膜孔蛋白及β-内酰胺类靶位编码基因研究

目的研究一株多重耐药鲍曼不动杆菌(Multi-drug-resistant Acinetobacter baumannii,MDR-ABA)J65可能存在的β-内酰胺类药物耐药机制。方法 MDR-ABA J65株分离自2011年12月某三甲医院住院患者痰标本,用gyrA和parC基因PCR扩增、测序和BLASTn比对确认菌种。用PCR法分析该菌株的PBP1a、PBP2、CarO和33种A^D类β-内酰胺酶编码基因,并对检出的β-内酰胺酶编码基因作了插入序列与β-内酰胺酶编码基因连锁检测。结果 MDR-ABA J65检出β-内酰胺酶编码基因bla TEM-1、bla ADC-62、bla OXA-23、bla OXA-66,插入序列与β-内酰胺酶编码基因连锁检测显示ISaba1-ADC-62和ISaba1-OXA-23为阳性。PBP1a、PBP2和CarO编码基因序列与鲍曼不动杆菌敏感株(SDF)相比均存在有义突变,且三维结构同源建模显示,与SDF株PBP1a、PBP2和CarO蛋白分子立体结构有明显差别。结论 MDR-ABA J65对β-内酰胺类耐药机制为PBPs和孔蛋白CarO变异及可移动遗传元件介异的β-内酰胺酶编码基因。

医院获得性肺炎患者醋酸钙-鲍曼不动杆菌复合体的鉴定和耐药基因研究

目的:了解我院医院获得性肺炎患者下呼吸道分离的醋酸钙-鲍曼不动杆菌复合体的菌种鉴定方法和耐药性,探讨其耐药机制。方法:收集2009-2014年临床分离的醋酸钙-鲍曼不动杆菌复合体共318株,用K-B法进行药敏试验,用gyr B多重PCR法对其进行菌种鉴定,检测碳青霉烯酶及金属β-内酰胺酶耐药基因。结果:318株醋酸钙-鲍曼不动杆菌复合体鉴定为鲍曼不动杆菌298株、不动杆菌基因种型3为5株、不动杆菌基因种型13TU 8株。对亚胺培南、头孢哌酮/舒巴坦、哌拉西林/他唑巴坦的不敏感率分别为78.0%、89%、92.1%。OXA型碳青霉烯酶基因OXA-51、OXA-23、OXA-24、OXA-58检出率分别为91.2%、65.7%、1.3%、3.8%;金属β-内酰胺酶基因IMP、VIM、GIM-1、SPM-1检出率分别为0.9%、34.6%、6.3%、0.9%;未检测到OXA-48、OXA-143、SIM-1、KPC、NDM-1等基因。结论:gyr B多重PCR法是一种快速、特异性高、可靠的鉴定鲍曼不动杆菌的方法。鲍曼不动杆菌对多种抗生素呈现高度耐药。我院鲍曼不动杆菌耐药性主要与OXA-23、VIM等耐药基因的表达有关。

2013-2016年老年病医院鲍曼不动杆菌临床分布及耐药性

目的了解2013—2016年某老年病医院鲍曼不动杆菌(AB)临床分布及耐药性变化趋势。方法采用回顾性研究对2013—2016年全院患者分离的AB标本来源、科室分布和耐药性进行分析。结果2013—2016年共分离1 712株AB,2013、2014、2015、2016年AB分离率逐年下降,分别为17.92%、17.17%、15.10%、11.81%;AB标本来源主要为痰(1 524株,89.02%),其次为尿(79株,4.61%)和血(37株,2.16%)。检出AB居前3位的科室依次为重症监护病房(798株,46.61%)、呼吸内科(507株,29.62%)、神经内科(156株,9.11%)。2013—2016年AB对绝大部分抗菌药物耐药率不断上升,对复方磺胺甲口恶唑的耐药率(25.68%~65.89%)较低,其次为头孢哌酮/舒巴坦(54.74%~68.00%),对亚胺培南的耐药率为71.40%~77.42%,对其余药物的耐药率均>60%;2013—2016年AB对头孢吡肟、头孢哌酮/舒巴坦、庆大霉素、妥布霉素、复方磺胺甲口恶唑的耐药率比较,差异有统计学意义(均P<0.05)。结论该院AB耐药率不断升高,需加强监测,促进抗菌药物合理使用,阻断AB的医院感染和传播。

鲍曼不动杆菌TEM-1型ESBLs基因及其多重耐药的研究

目的分析产TEM-1型超广谱β-内酰胺酶(ESBLs)鲍曼不动杆菌的耐药性及其基因序列。方法用聚合酶链式反应(PCR)扩增产ESBLs鲍曼不动杆菌的TEM-1型耐药基因,用克隆测序方法分析质粒上TEM-1型ESBLs基因。结果15株产ESBLs鲍曼不动杆菌中,TEM-1型ESBLs阳性菌株有12株,TA克隆后测序表明,与鲍曼不动杆菌(AY560328.1)blaTEM-1基因序列99%同源。结论质粒上带产TEM-1型ESBLs的鲍曼不动杆菌,blaTEM-1基因与鲍曼不动杆菌多重耐药密切相关。

头孢哌酮-舒巴坦联合中药对泛耐药鲍曼不动杆菌抗菌活性的研究

目的通过体外及体内抗菌实验,观察中药颗粒剂与头孢哌酮-舒巴坦的联合作用对泛耐药鲍曼不动杆菌(PDR-AB)的抗菌效果。方法采用不同浓度头孢哌酮-舒巴坦与8种中药颗粒剂(五倍子、黄连、黄芩、薄荷、连翘、乌梅、五味子及大黄)相结合,通过计算各自单用药最低抑菌浓度(MIC)及部分抑菌浓度指数(FIC)观察其对36株PDR-AB的体外抑菌效果,选取适当的方案分组后通过检测中性粒细胞、肿瘤坏死因子-α(TNF-α)及降钙素原(PCT)研究其对PDR-AB感染小鼠的抑菌作用。结果头孢哌酮-舒巴坦联合五倍子、黄连及黄芩具有协同作用,联合五味子、薄荷及连翘具有相加作用,联合乌梅和大黄显示为无关作用,且头孢哌酮-舒巴坦联合五倍子比单用药能更显著地降低感染小鼠的中性粒细胞数量、TNF-α及PCT水平。结论头孢哌酮-舒巴坦和五倍子联用对PDR-AB有明显的抑菌作用,可用于治疗由PDR-AB引起的重症感染。