Occurrence of tetracycline residues and antimicrobial resistance in gram negative bacteria isolates from cattle farms in Spain

The usage of antibiotics in animal husbandry has dramatically increased the concentration of antibiotic residues and has promoted the development and abundance of antibiotic resistance in manure. When it is spread onto agricultural land, both residues of antibiotics and bacteria carrying antibiotic resistance genes may be introduced into the environment. In this research, we isolated resistant gram negative bacteria from manure produced in two dairy and two beef cattle farms, located in Madrid (Spain), to determine their resistance to seventeen representative antibiotics commonly used in veterinary therapy. A total of 63 isolates were used to assess the overall bacterial antimicrobial resistance on cattle manure samples. Predominant species were Escherichia coli and Comamonas testosteroni accounting for 25% and 19.6% of the total, respectively. The most found antimicrobial resistances in gram-negative bacteria were to tetracycline (66.7%), sulphamethoxazole (55.6%), ampicillin (52.4%), cephalothin (46.0%), chloramphenicol (44.4%), nalidixic acid (39.7%) and trimethroprim- sulphamethoxazole (33.3%). The mean of resistance and the percentage of multi-resistant bacteria in beef farms were higher and statistically significant when compared to dairy farms which is opposite from the findings of the previous studies. The presence of three tetracyclines in all manure samples was also examined with stable recoveries (76% - 82%) and high sensitivity (limit of quantification 0.015 - 0.03 μg/kg). The concentrations of tetracyclines detected (<0.015 - 10 mg/kg) were consistent to the theoretical tetracycline levels in manure in Spain according to the ex- cretion rate of these antibiotics and the values re-ported in scientific literature in other European coun- tries.

pLoc_Deep-mGneg: Predict Subcellular Localization of Gram Negative Bacterial Proteins by Deep Learning

The recent worldwide spreading of pneumonia-causing virus, such as Coronavirus, COVID-19, and H1N1, has been endangering the life of human beings all around the world. In order to really understand the biological process within a cell level and provide useful clues to develop antiviral drugs, information of Gram negative bacterial protein subcellular localization is vitally important. In view of this, a CNN based protein subcellular localization predictor called “pLoc_Deep-mGnet” was developed. The predictor is particularly useful in dealing with the multi-sites systems in which some proteins may simultaneously occur in two or more different organelles that are the current focus of pharmaceutical industry. The global absolute true rate achieved by the new predictor is over 98% and its local accuracy is around 94% - 100%. Both are transcending other existing state-of-the-art predictors significantly. To maximize the convenience for most experimental scientists, a user-friendly web-server for the new predictor has been established at http://www.jci-bioinfo.cn/pLoc_Deep-mGneg/, which will become a very useful tool for fighting pandemic coronavirus and save the mankind of this planet.

Multiple Antibiotic Resistant Index of Gram-Negative Bacteria from Bird Droppings in Two Commercial Poultries in Enugu, Nigeria

Antimicrobial resistance refers to the ability of microorganisms to grow in the presence of an antimicrobial agent at a concentration that will normally kill or inhibit their growth. Antimicrobial resistance has become a major global threat making treatment of infections tougher especially with high cost of treatment in humans and animals. This study was done to determine the Multiple Antibiotic Resistant Index (MARI) of Gram-negative bacteria from bird droppings in two commercial poultries in Enugu. Forty (40) samples were collected from each of the poultries. Isolates were identified by standard microbiological methods. The isolates identified were Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Citrobacter spp, Proteus spp. and, Enterobacter spp. Antibiotic susceptibility testing was carried out using disc diffusion technique. The organisms were tested against pefloxacin, augmentin (amoxicillin and clavulanic acid), ceftazidime, streptomycin, ciprofloxacin, gentamycin, cephalothin, neomycin and ofloxacin. The result of the susceptibility test showed that Proteus spp had the highest resistance and MARI value of 0.5 and 1.0 respectively. The other MARI values were Escherichia coli (0.9), Klebsiella pneumonia (0.9), Pseudomonas aeruginosa (0.8), Citrobacter spp (0.8) and Enterobacter spp (0.7). These results suggest that bacterial organisms from poultry source can contribute significantly to the spread of multi-antibiotic resistant organisms. This could arise from the indiscriminate use of antibiotics in bird feeds in poultries.

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.

The Increased Frequency of Carbapenem Resistant Non Fermenting Gram Negative Pathogens as Causes of Health Care Associated Infections in Adult Cancer Patients

Background and Aim: Multi drug resistant Non fermenting gram negative bacilli (NFGNB) have emerged as a major cause of health-care associated infections especially in immunocompromised hosts. The aim of the study was to investigate the prevalence of NFGNB as a cause of health-care associated infections (HAI) in cancer patients and determine their resistance pattern. Patients and Methods: During the study period, 158 NFGNB isolates were collected. Microscan Walk Away 9 was used for identification and testing for the metallo-β-lactamases (MBLs) was done by Imipenem-EDTA combined disk synergy test (CDST-IPM). Results: NFGNB represented 29.0% of infections caused by gram negative organisms. Carbapenem resistance, the multi-drug resistant (MDR) phenotype, and MBL production were documented in 70%, 63%, and 59% of NFGNB isolates, respectively. MDR-NFGNB rates were significantly higher among hospitalized patients, medical department and those with longer duration of hospital stay (p = 0.034, 0.026, 0.019;respectively) than non MDR-NFGNB. Conclusion: A high level of carbapenem and multi-drug resistance were detected among the non-fermenter pathogens isolated from hospitalized cases and were more frequently encountered in high risk adult cancer patients requiring longer duration of hospitalization. The MDR-NFGNB are constituting important causes of health-care associated infections in cancer patients.

Review: Gram Negative Bacteria in Brewing

Gram negative aerobic bacteria such as Acetic Acid Bacteria, which include Acetobacter and Gluconobacter, have historically caused significant problems to brewers. Although incidences of spoilage have recently reduced as a result of improvements in beer packaging, these bacteria are still a concern in dispense systems in pub breweries, public houses and cask conditioned beers. Gram negative facultative bacteria of the genus Zymomonas can spoil primed cask conditioned beer and cider. There is a wide range of Enterobacteraeceace which are found within brewery environments and they serve as indicator microorganisms for hygiene and sanitation. Gram negative strictly anaerobic bacteria such as Pectinatus and Megasphaera have recently emerged as a significant threat due to the improvement in reduction of oxygen levels in beer and an increase in production of unpasteurised beer. Pectinatus and Megasphaera are sensitive to routine cleaning agents used in breweries, but they can survive and proliferate in biofilms eventually causing spoilage of beer. This review focuses on Gram negative aerobic, facultative anaerobic and strictly anaerobic brewery related spoilage bacteria.

2014~2019年北京某三甲医院腹腔感染革兰阴性菌的耐药情况与合理用药的探讨

目的:通过对北京某三甲医院2014~2019年期间采集的腹腔感染革兰阴性菌的鉴定和对常用抗菌药物的药敏测试,为近年院内腹腔感染革兰阴性菌的流行病学和耐药情况提供参考依据。方法:使用定制药敏板通过Trek系统进行抗菌药物敏感性测试并依据CLSI2021标准进行药敏判读。结果:2014~2019年期间共收集革兰阴性菌464株,其中肠杆菌目细菌355株,社区获得性感染菌株123株、医院获得性感染菌株341株,ICU收集的菌株187株。药敏试验显示:该院碳青霉烯类抗菌药物耐药菌中,大肠埃希菌对目前国内常用的12种抗菌药物几乎都呈现不敏感状态,仅阿米卡星的敏感率为81.8%;除黏菌素外,肺炎克雷伯菌几乎无抗菌药物可选择;铜绿假单胞菌目前对环丙沙星、头孢吡肟、阿米卡星的敏感率均为75.0%。该院喹诺酮类抗菌药物耐药菌中,对大肠埃希菌治疗有效率达到82.5%及以上的抗菌药物有厄他培南、亚胺培南、美罗培南、阿米卡星和黏菌素;亚胺培南、美罗培南和阿米卡星对肺炎克雷伯菌的敏感率仅在65.0%左右;对于铜绿假单胞菌,可选的抗菌药物有头孢他啶、头孢吡肟和阿米卡星(敏感率均为66.7%)。该院第三代头孢菌素耐药菌中,大肠埃希菌对亚胺培南、美罗培南、阿米卡星和黏菌素的敏感率均在93.0%以上;肺炎克雷伯菌对亚胺培南、美罗培南和阿米卡星的敏感率在71.4%~79.2%;铜绿假单胞菌对环丙沙星、美罗培南、阿米卡星和黏菌素的敏感率在83.3%以上。无论是碳青霉烯类抗菌药物耐药鲍曼不动杆菌,还是喹诺酮类抗菌药物耐药鲍曼不动杆菌,或者是第三代头孢菌素耐药鲍曼不动杆菌,除黏菌素的敏感率为97.6%~100.0%外,几乎无常规抗菌药物可供选择。结论:腹腔感染革兰阴性菌总体耐药形势比较严峻,持续监测本地区医院病原菌检出率和合理选择对耐药菌株有效的抗菌药物治疗非常重要。

Pylephlebitis-induced acute liver failure: A case report and review of literature

BACKGROUND Pylephlebitis is an extremely rare form of septic thrombophlebitis involving the portal vein,carrying high rates of morbidity and mortality.CASE SUMMARY We present a case of a 42-year-old male with no past medical history who presented with acute onset of abdominal pain and altered mental status with laboratory tests demonstrating new-onset acute liver failure.Pylephlebitis was determined to be the underlying etiology due to subsequent workup revealing polymicrobial gram-negative anaerobic bacteremia and complete thrombosis of the main and left portal veins.To our knowledge,this is the first documented case of acute liver failure as a potential life-threatening complication of pylephlebitis.CONCLUSION Our case highlights the importance of considering pylephlebitis in the broad differential for abdominal pain,especially if there are co-existing risk factors for hypercoagulability.We also demonstrate that fulminant hepatic failure in these patients can potentially be reversible with the immediate initiation of antibiotics and anticoagulation.

猫爪草灰霉病菌拮抗细菌的分离与筛选

为筛选出对猫爪草灰霉病菌(Botrytis cinerea)具有拮抗作用的细菌,本试验从不同植物根际土壤中分离细菌,通过平板对峙方法测定其对猫爪草灰霉病菌的拮抗作用并对其进行初步鉴定。结果表明:分离纯化的106株细菌,通过初筛,对猫爪草灰霉病菌具有拮抗作用的共有13株,其编号分别是BDYM-1、BDYM-2、BDHS-3、DFYM-1、SQBC-1、SQTS-2、SQBC-8、XJMH-1、NYHS-3、ZKFQ-1、ZKFQ-2、ZKFQ-3和ZKFQ-6;经过复筛,在初筛基础上选定了5株对猫爪草灰霉病病原菌抑菌效果较好的拮抗细菌,分别是BDYM-1、BDHS-3、SQTS-2、SQBC-8、ZKFQ-3;对这5株菌株进行细菌发酵液测定后,其中SQBC-8抑菌效果最好,抑菌率为64.4%,BDHS-3菌株抑菌效果相对稳定。通过形态特征观察进行了初步鉴定,鉴定结果为5种菌株均为革兰氏阳性菌。

Serum procalcitonin elevation in elderly patients with coronary heart disease at the onset of septic shock caused by either Gram negative or Gram positive bacteremia

Background Septic shock caused by bacteremia is a life-threatening infection whose prognosis is highly de- pendent on early recognition and appropriate treatment. Procalcitonin （PCT） has been shown to accurately and quickly distinguish bacteremia from noninfectious inflammatory states in critically severe patients. However, the extent of PCT magnitude elevation according to the Gram stain result in elderly patients with coronary heart disease （CHD） at the onset of septic shock caused by bacteremia varies, and has not been clearly elucidated. Methods The medical records of advanced age （non-neutropenic） patient with CHD and septic shock between Mar 2013 and Jun 2015 who had bacteremia caused by either Gram-positive （GP） bacteria or Gram-negative （GN） bacteria were reviewed, and the levels of PCT, C- reactive （CRP） protein and white blood cells count （WBC） in both groups were analyzed. Results 75 episodes of either GN bacteremia （n = 40） or GP bacteremia （n = 35） were enrolled. PCT levels were found to be markedly higher in patients with GN bacteremia than in those with GP bacteremia [（8.93± 17.58） vs. （64.42± 58.56） ng/L （P 〈 0.001）], whereas there was no significant differ- ence in CRP and WBC （P 〉 0.05）. Moreover, a high PCT level was found to be independently associated with GN bacteremia in this study population. A PCT level of 19.69 ng/mL yielded a 72.5% sensitivity, a 91.4% specificity, an 8.43 positive likelihood ratio and a 0.30 negative likelihood ratio for GN-related bacteremia in the study cohort [AUROCC = 0.870 （0.041）, 95% CI （0.790-0.949）]. Conclusion In an elderly patient （non-neutropenic） with CHD and septic shock, GN bacteremia could be associated with higher PCT values than those found in GP bacteremia （PCT 〉 19.69 ng/mL）.

黄芩苷对代谢性炎症及肠道菌群的调节作用探讨

【目的】探讨黄芩苷对高脂血症模型代谢性炎症及肠道菌群的调节作用。【方法】选取32只C57BL/6J雄性小鼠随机平均分为正常组、模型组、黄芩苷高剂量组(剂量为50 mg·kg-1·d-1)、黄芩苷低剂量组(剂量为25 mg·kg-1·d-1)。高脂饲料喂养3周后,2个黄芩苷用药组分别给予不同浓度黄芩苷灌胃5周。采用酶联免疫吸附法检测各组小鼠血清血脂水平以及肿瘤坏死因子-α(TNF-α)、白细胞介素-6(IL-6)及内毒素水平,采用Miseq平台对小鼠肠道粪便微生物进行基因测序。【结果】与正常组比较,模型组总胆固醇及低密度脂蛋白水平显著升高(P<0.01),高密度脂蛋白水平显著降低(P<0.01),血清TNF-α、IL-6和内毒素水平显著升高(P<0.01);黄芩苷高剂量组的TNF-α、IL-6、内毒素水平均较模型组显著降低(P<0.05或P<0.01),黄芩苷低剂量组内毒素水平亦较模型组显著降低(P<0.01)。测序生物信息学分析发现,在门的水平,模型组脱铁杆菌门和变形杆菌门数目较正常组显著增多,疣微菌门数目较正常组显著减少。在属的水平,模型组Christensenella、uncultured_Peptococcaceae、脱硫弧菌属数目较正常组显著增多,而粪球菌属、Akkermansia及uncultured_Lachnospiraceae数目较正常组显著减少;黄芩苷高、低剂量组脱硫弧菌属丰度均较模型组降低。各组革兰氏阴性菌与革兰氏阳性菌数目之比,模型组较正常组显著升高(P<0.05),黄芩苷低剂量组较模型组显著降低(P<0.05)。【结论】黄芩苷能治疗高脂饮食引起的代谢性炎症,这可能与黄芩苷能调节肠道菌群的结构有关。

2010年中国12所教学医院革兰阳性球菌耐药性研究

目的调查2010年我国12所教学医院临床分离的革兰阳性球菌的耐药性。方法收集2010年6-12月9个城市12所教学医院临床分离的1 181株非重复革兰阳性球菌。采用琼脂稀释法测定抗菌药物的最低抑菌浓度(MIC)值,计算不同病原菌对常用临床抗菌药物的耐药率。结果金葡菌和凝固酶阴性葡萄球菌中耐苯唑西林菌株分别占40.6%(191/470)和79.6%(187/236);不同标本苯唑西林耐药金葡菌(MRSA)检出率为22.2%～72.7%。在ICU患者中,MRSA的检出率为71.4%,高于MRSA在住院患者中的比率。未发现对替考拉宁、万古霉素和利奈唑胺耐药的金葡菌;替加环素对金葡菌的MIC值范围为0.032～0.5 mg/L。在肠球菌属中发现10株屎肠球菌和2株粪肠球菌对万古霉素耐药。粪肠球菌和屎肠球菌对替加环素的敏感率均为100%,对利奈唑胺的敏感率分别为98.3%和100%。按青霉素非脑膜炎株折点判读,肺炎链球菌中青霉素耐药株(PRSP)的比率为6.0%(14/232),其中5岁以下儿童中PRSP的比率为13.8%(9/65),65岁以上的老人中PRSP的发生率为5.1%(3/59);未发现对替考拉宁、万古霉素、利奈唑胺、替加环素耐药的肺炎链球菌。结论葡萄球菌中MRSA检出率在ICU患者中较门诊和住院患者高,MRSA主要分离自呼吸道标本和各种分泌物和脓液标本。万古霉素耐药的肠球菌在我国发生率低。PRSP在5岁以下儿童中的比率明显高于其他年龄组。替考拉宁、万古霉素、利奈唑胺、替加环素对葡萄球菌、粪肠球菌、屎肠球菌和肺炎链球菌具有很好的抗菌活性。

2018年中南大学湘雅医院细菌耐药性监测

目的了解2018年中南大学湘雅医院临床分离细菌的分布和药物敏感性,为临床合理使用抗菌药物提供依据。方法采用标准纸片扩散法或自动化仪器检测法,测定细菌对临床常用抗菌药物的敏感性,根据CLSI 2018年标准判断结果,用WHONET 5.6软件进行数据分析。结果 2018年分离非重复菌株7362株,其中革兰阳性菌2 543株,占34.5%;革兰阴性菌4819株,占65.5%。MRSA和MRCNS分别占各自菌种的30.3%和75.5%。检出3株对利奈唑胺耐药的粪肠球菌。肺炎链球菌非脑膜炎分离株中儿童100%为青霉素敏感株(PSSP),成人为95.8%。大肠埃希菌、肺炎克雷伯菌和奇异变形杆菌中产ESBL菌株分别占54.0%、34.8%和34.9%。耐碳青霉烯类大肠埃希菌、肺炎克雷伯菌、铜绿假单胞菌、鲍曼不动杆菌分别占各自菌种的2.6%、20.0%、23.5%、87.5%。鲍曼不动杆菌对替加环素的耐药率较低(4.4%)。流感嗜血杆菌β内酰胺酶阳性率为41.6%。结论该院细菌耐药形势比较严峻,应重视细菌耐药监测工作并采取有效的医院感染控制措施。

抗菌药物的临床应用与耐药性监测

目的:掌握细菌耐药规律,提高合理用药水平及治疗效果。方法:从本院2007年全年住院病历中随机抽取240份,按抗菌药物用药频度(DDDs)、实际用药天数、药物利用指数(DUI)和联合用药种数进行综合统计。收集2007年本院临床分离菌株,采用Kirby Bauer法进行药敏试验,并以WHONET5.4软件进行菌株数据分析。结果:抗菌药物DDDs排序结果显示,头孢菌素类(5种)、喹诺酮类(1种)临床用药最为广泛,其中左氧氟沙星的用量最高。本院临床共分离病原菌1501株,其中,革兰阳性(G+)菌412株(27.45%),革兰阴性(G-)菌970株(64.62%),真菌119株(7.93%)。药敏试验结果中G+菌对万古霉素、替考拉宁最敏感,对其他抗菌药物敏感性不佳;G-菌对碳青霉烯类最敏感,对头孢哌酮/舒巴坦钠和阿米卡星敏感度次之。结论:对细菌的耐药监测,是掌握细菌耐药规律的重要手段,是提高合理用药水平,控制ADR发生率,遏制细菌耐药性的重要途径。

纳米TiO_2抑菌机理研究

在近荧光灯(10cm)照射下,纳米二氧化钛(TiO2)具有很强的光催化杀菌作用.作者通过TiO2对多种代表微生物的抑菌特性以及对TiO2光催化杀灭革兰氏阴、阳性细菌进行对比、常规培养验证和透射电镜观察得出结论:TiO2光催化灭菌首先是从细菌细胞壁开始,其产生的自由基能破坏细胞壁结构,使细胞壁断裂、破损,质膜解体,然后进入胞体内部破坏内膜和细胞组分,使细胞质凝聚,导致细胞内容物溢出,可出现菌体空化现象.

慢性阻塞性肺病患者继发革兰阴性杆菌医院肺炎的菌型及耐药性研究

目的 探讨慢性阻塞性肺病 (COPD)继发医院肺炎的发病机理、病原菌菌型分布及耐药现状。方法 对本院 COPD继发医院革兰阴性杆菌 (GNB)肺炎患者痰液中分离的 2 98株 GNB进行菌型分类 ,选用 14种常用抗菌药物对 2 98株 GNB进行了体外 MIC药敏试验。结果 2 98株 GNB占 COPD继发医院肺炎病原菌总数的6 8.7% ,其中以非发酵菌为主 ,占 4 5 .3% ;肠杆菌科细菌居第 2 ,占 4 3.3% ;菌种分类 :铜绿假单胞菌、肺炎克雷伯菌、流感嗜血杆菌分别居 1、2、3位 ;本组病例中还分离出 18株产超广谱 β-内酰胺酶肠杆菌科细菌 ;药敏结果表明 ,所有 GNB对抗菌药物耐药率均呈上升趋势。结论 GNB为 COPD继发肺炎的主要致病菌 ,在临床治疗中 ,必须合理使用抗生素 ,才能控制 GNB的耐药趋势。

2007年中国10所教学医院革兰阳性球菌耐药性研究

目的调查我国10所教学医院革兰阳性球菌临床分离株的耐药性。方法收集2007年下半年全国10所教学医院分离的非重复革兰阳性球菌931株,以琼脂稀释法测定抗菌药物的MIC。采用CLSI2008年版判断药敏结果。结果152株肺炎链球菌(全部为非脑脊液标本,采用静脉青霉素折点判断),青霉素耐药株(PRSP)和青霉素中介株(PISP)分别占2.6%和25.0%。所有肺炎链球菌均对万古霉素和替考拉宁高度敏感;对左氧氟沙星和莫西沙星的敏感率分别为98.0%和100%;对阿莫西林-克拉维酸、头孢曲松和氯霉素的敏感率分别为72.4%、80.9%和84.2%;青霉素敏感的肺炎链球菌(PSSP)对头孢丙烯和头孢克洛的敏感率分别为64.5%和59.1%,但PISP和PRSP对这2种抗生素均耐药。金葡菌和凝固酶阴性葡萄球菌(CSN)中耐苯唑西林菌株分别占49.5%和84.8%。无替考拉宁和万古霉素耐药的金葡菌;共发现替考拉宁中介的苯唑西林耐药溶血葡萄球菌(MRSH)3株和苯唑西林耐药表皮葡萄球菌(MRSE)1株。MRSA对氯霉素、复方磺甲口恶唑和利福平的敏感率分别为83.2%、71.1%和50.0%。粪肠球菌和屎肠球菌对高浓度庆大霉素耐药率分别为60.4%和75.9%。未发现对万古霉素和替考拉宁耐药的粪肠球菌;2株屎肠球菌对万古霉素耐药。除氯霉素和四环素外,粪肠球菌对其他所测抗菌药物的敏感率均高于屎肠球菌。结论各地区革兰阳性球菌对抗菌药物的耐药性有所差异,PISP有逐年上升趋势。替考拉宁和万古霉素对革兰阳性球菌具有很好的抗菌活性。

血清降钙素原定量检测在细菌感染诊断中的临床意义

目的了解血清降钙素原(PCT)定量检测在不同病原体(细菌与非细菌、革兰阳性球菌与革兰阴性杆菌)、不同类型(全身感染与呼吸系统、泌尿系统等局部感染)、不同人群(男性与女性、不同年龄段)感染的临床应用价值。方法分离鉴定从2014年1至12月间住院或门诊疑似感染患者送检样本中的细菌和真菌,同时采用定量方法检测患者的血清PCT水平,并进行统计学分析。结果血清PCT水平在细菌感染组中升高显著,而在真菌及非细菌感染组中升高不明显,二者间差异有统计学意义(P<0.05);细菌全身感染组PCT水平明显高于细菌局部感染组(P<0.05);在细菌局部感染中,呼吸系统、泌尿系统和神经系统感染组间血清PCT水平差异无统计学意义(P>0.05)。在细菌感染中,革兰阴性杆菌感染患者血清PCT水平高于革兰阳性球菌感染患者(P<0.05);男性与女性细菌感染患者之间血清PCT水平差异无统计学意义(P>0.05),各年龄组之间差异亦无统计学意义(P>0.05)。结论 PCT可作为细菌感染尤其是全身感染的重要指标。

急性白血病患者革兰氏阴性菌血流感染的药敏分析及预后

目的:分析急性白血病(acute leukemia,AL)患者合并革兰氏阴性菌(Gram negative bacterium,G-菌)血流感染的病原学分布、药敏特征及预后,为降低AL患者感染相关病死率提供依据。方法:收集2010年1月至2018年12月湖南省三家大型医院血液科1055例合并血流感染的AL患者的临床资料,并对其中G-菌感染患者的病原学、药敏数据及临床特征进行分析。结果:622例合并血流感染的AL患者为G-菌感染,主要致病菌为大肠埃希菌(277株,44.53%)、肺炎克雷伯菌(138株,22.19%)、铜绿假单胞菌(81株,13.02%)。多数G-菌对碳青霉烯类药物及β内酰胺/β内酰胺酶抑制剂敏感率较高。疾病状态、Pitt菌血症评分≥4、使用血管活性药物、启动敏感抗菌药物治疗时间>48 h是AL患者合并G-菌血流感染30 d内死亡的独立危险因素(P<0.05)。结论:AL患者合并G-菌血流感染的合理抗菌治疗需充分了解当地病原菌流行病学及药敏监测数据,及时应用覆盖最常见和毒力较强病原菌的广谱抗菌药物,并根据药敏结果及疗效调整用药。

革兰氏阴性细菌Ⅵ型分泌系统的研究进展

细菌的Ⅵ型分泌系统(T6SS)参与了细菌与细菌间、细菌与宿主间的相互作用,在细菌的存活及致病中发挥着重要的作用。本研究中综述了细菌T6SS的发现与命名、结构与组成,调控机制(Fur、σ54依赖性激活因子、表面缔合、群体感应)与作用机制的最新研究进展,并对其下一步的研究方向进行展望。本研究结果可为深入研究细菌T6SS在细菌间及细菌与宿主间的作用机制,研制基于T6SS的疫苗或靶向药物,寻找对细菌T6SS有效的防控措施提供参考。