Horizontal gene transfer—emerging multidrug resistance in hospital bacteria

The frequency and spectrum of antibiotic resistant infections have increased worldwide during the past few decades. This increase has been attributed to a combination of microbial characteristics, the selective pressure of antimicrobial use, and social and technical changes that enhance the transmission of resistant organisms. The resistance is acquired by mutational change or by the acquisition of resistance-encoding genetic material which is transfered from another bacteria. The spread of antibiotic resistance genes may be causally related to the overuse of antibiotics in human health care and in animal feeds, increased use of invasive devices and procedures, a greater number of susceptible hosts, and lapses in infection control practices leading to increased transmission of resistant organisms. The resistance gene sequences are integrated by recombination into several classes of naturally occurring gene expression cassettes and disseminated within the microbial population by horizontal gene transfer     

How could we reduce antibiotic use in critically ill patients?

The role of antibiotic pressure in the selection of antibiotic-resistant bacteria is still under debate in the scientific community and often confounded by scarce data on antibiotic usage. Several studies demonstrated that prior antibiotic exposure is likely to increase patient's colonization and infection by antimicrobial-resistant bacteria. Of even more concern is the significant mortality associated with these infections, in particular in critically ill patients. Therefore, the control of antibiotic usage in intensive care units (ICUs) is of paramount importance. Antibiotic stewardship programmes (ASP) have been demonstrated to represent a useful intervention to reduce the inappropriate antibiotic usage in hospitalized patients. A few trials were performed in ICU population with positive results. The major risk we foresee for the implementation of ASP for ICU patients is the lack of consideration of local ecology and strict quality indicators. The development of new pattern of antimicrobial resistance might be ascribed to an inappropriate ASP. European networks to define best strategies and antibiotic-care bundles need to be supported at national and international level. To optimize antibiotic use in the ICU and to fight against the spread of resistance, it is extremely important to adopt a multifaceted approach including ASP.     

内科监护病房的感染分析

目的了解本院内科监护病房的感染和细菌耐药情况.方法按<全国临床检验操作规程>进行分离培养,细菌用法国梅里埃公司VITEK-60自动细菌鉴定仪鉴定菌种,药敏试验采用K-B法.真菌用梅里埃公司API 20C AUX鉴定条和ATB FUNGUS药敏条进行鉴定和药敏试验.结果革兰阴性杆菌感染占36.3%,革兰阳性球菌占27.4%,真菌占36.3%.革兰阴性杆菌对不同的抗生素敏感性不一,革兰阳性球菌对万古霉素、替考拉宁敏感性高,真菌对5-氟胞嘧啶、两性毒素B等抗真菌药物敏感.结论多数细菌呈多重耐药性,完善消毒制度和合理使用抗生素对降低感染率和控制耐药菌株的传播具有重要意义.     

Antibacterial resistance in the intensive care unit: mechanisms and management

The incidence of multiple antimicrobial resistance of bacteria which cause infections in the intensive care unit is increasing. These include methicillin-resistant Staphylococcus aureus and vancomycin-resistant enterococci, penicillin-resistant Streptococcus pneumoniae and cephalosporin and quinolone resistant coliforms. More recently, pan antibiotic resistant coliforms, including carbapenems, have emerged. The rapidity of emergence of these multiple antibiotic-resistant organisms is not being reflected by the same rate of development of new antimicrobial agents. It is, therefore, conceivable that patients with serious infections will soon no longer be treatable with currently available antimicrobials. Strict management of antibiotic policies and surveillance programmes for multiple resistant organisms, together with infection control procedures, need to be implemented and continuously audited. As intensive care units provide a nidus of infection for other areas within hospitals, this is critically important for prevention of further spread and selection of these resistant bacteria.     

ICU患者建立人工气道后获得性肺部感染29例临床分析

目的　了解ICU患者建立人工气道后获得性肺部感染的病原菌及药敏情况 ,探讨ICU获得性肺部感染的危险因素及抗菌药物的合理应用。方法　对 2 9例建立人工气道后获得性肺部感染的ICU患者的痰增减及药敏结果进行分析。结果　 5 1次痰标本共培养出 6 9株细菌和 12株真菌 ,其中革兰氏阴性菌 46株(72 4 6 %) ,尤以铜绿假单胞菌居多 (2 2株 ,2 7 16 %)。结果　本组ICU患者建立人工气道后获得性肺部感染的病原菌以革兰氏阴性菌为主 ,五种主要致病菌对各种抗生素均有不同程度的耐药。针对造成感染的各种因素应制定一系列的防范措施 ,同时对危重患者的抗菌治疗应有效、合理地用药 ,尽早分离病原菌 ,一旦病原菌确定 ,应予以针对性药物治疗。     

Antimicrobial stewardship in the intensive care unit: a focus on potential pitfalls

Patients in the intensive care unit (ICU) have many risk factors for resistant pathogens such as prolonged length of stay, frequent and broad-spectrum antimicrobial therapy, presence of foreign materials, and proximity with other patients. However, of the risk factors associated with acquisition of resistant pathogens, inappropriate use of antimicrobial agents has been the most implicated. Thus, many health care institutions have adopted antimicrobial stewardship programs (ASPs) as a mechanism to ensure more appropriate antimicrobial use. ASPs can have a significant impact in the ICU, leading to improved antimicrobial use and resistance patterns and decreased infection rates and costs, due to the inherent nature of infections encountered and high and often inappropriate antibiotic utilization in this setting. However, certain challenges exist for ASPs in the ICU including issues with infrastructure and personnel, information technology, the core ASP strategy, patient-specific factors, conversion of intravenous to oral therapy, and dose optimization. The combination of comprehensive infection control (IC) and effective antimicrobial stewardship can prevent the emergence of resistance among microorganisms and may decrease the negative consequences associated with antimicrobial misuse.     

2012年8月—2015年2月武汉大学人民医院消化内科院内获得性感染病原菌的分布、耐药性及危险因素分析

目的探讨武汉大学人民医院消化内科院内获得性感染病原菌的分布、耐药性及危险因素分析。方法选取2012年8月—2015年2月武汉大学人民医院消化内科院内获得性耐药菌感染的住院患者64例,对分离出的病原菌的分布、耐药性及危险因素分析进行分析。结果检出耐药菌的标本主要来源于尿液和痰液;分离出的耐药菌菌株中革兰阳性菌20株、革兰阴性菌44株。革兰阳性菌除对利奈唑胺敏感外,其余均有不同程度的耐药;革兰阴性菌耐药严重;住院患者院内获得性感染的主要危险因素为年龄、手术和尿管。结论临床医护人员应加强关注住院患者院内获得性耐药菌感染的相关危险因素,预防感染的发生,合理使用抗菌药物。     

儿科血流性感染病原菌构成及药敏分析

目的了解儿童血流性感染的病原体构成和药敏情况,以指导临床治疗。方法回顾性分析2009年1月至2012年1月从儿童血液标本中培养出的病原体资料,用WHONET 5.4软件分析病原体的构成情况及其药敏情况。结果共培养出病原菌180株,细菌161株：革兰阳性菌94株,其中葡萄球菌69株;革兰阴性菌67株,其中大肠埃希菌25株,革兰阳性菌主要对万古霉素、替考拉宁、利奈唑烷敏感,而革兰阴性菌对碳青霉烯类抗生素敏感,对常用抗生素如阿莫西林、头孢菌素等存在广泛的耐药。真菌有19株,对两性霉素、伊曲康唑、氟康唑等均敏感。结论血流性感染的病原体构成以革兰氏阳性菌占优势,致病的细菌对青霉素类及头孢类抗生素存在较高耐药性,真菌感染有上升趋势,临床上应合理应用抗生素,根据药敏选择药物,减缓耐药的出现。     

Clinical,economic and societal impact of antibiotic resistance

The concern over antibiotic resistance has been voiced since the discovery of modern antibiotics > 75 years ago. The concerns have only increased with time, with efforts to control resistance caused by widespread overuse of antibiotics in human medicine and far more than appreciated use in the feeding of animals for human consumption to promote growth. The problem is worldwide, but certain regions and selected health care institutions report far more resistance, including strains of Gram-negative bacteria that are susceptible only to the once discarded drugs polymyxin B or colistin, and pan-resistant strains are on the rise. One of the central efforts to control resistance, apart from antimicrobial stewardship, is the development of new antimicrobial agents. This has lagged significantly over the past 10 – 15 years, for a variety of reasons; but promising new agents are being developed, unfortunately none thus far addressing all potentially resistant strains. There is the unlikely, but not unreal, possibility that we could return to a pre-antibiotic era, where morbidity and mortality rates have risen dramatically and routine surgical procedures are not performed for fear of post-operative infections. The onus of control of resistance is a moral imperative that falls on the shoulders of all.     

New antibiotics for the treatment of serious infections in intensive care unit patients

Objective: Nowadays, the infections of patients admitted to intensive care units (ICUs) are a major public health problem; this is due to several factors, in primis an increase in antibiotic resistance and the inappropriate use of antibiotics.

Methods: We briefly focus on on both new antibiotics approved by the US Food and Drug Administration (FDA) and the European Medicines Agency (EMA) in the last decade (2010–2019), and on agents in an advanced phase of development that have been developed, or are already approved, for the treatment of serious infections due to multidrug-resistant bacteria, both Gram-positive and Gram-negative bacteria.

Results: An adequate knowledge of the new antibiotics will reduce their inappropriate use with the consequent reduction in the onset of new resistance and decreasing health care costs.

Conclusion: Antimicrobial stewardship programs to optimize antimicrobial prescribing and to preserve the effectiveness of the new antimicrobial agents are urgently needed'.     

病房强化治疗下肺癌患者院内下呼吸道感染病原菌的多重耐药性分析

目的 分析病房强化治疗下肺癌患者院内下呼吸道感染病原菌的多重耐药性.方法 选取2005年4月至2014年11月病房强化治疗下院内肺癌下呼吸道感染患者320例为研究对象,分析下呼吸道病原菌分离株和多重耐药性.结果 共分离448株致病菌,其中革兰氏阴性杆菌为238株(53.1％),主要为铜绿假单胞菌(15.2％)、肺炎克雷伯菌(10.5％)等;革兰氏阳性菌为84株(18.8％),主要为金黄色葡萄球菌(8.3％);真菌126株(28.1％).培养两种致病菌占52.9％,真菌感染合并革兰氏阴性杆菌占65.4％.革兰氏阳性杆菌对万古霉素敏感性达到100％,革兰氏阴性杆菌对头孢哌酮、阿米卡星以及环丙沙星等敏感性高,致病菌存在多重耐药性.结论 肺癌患者院内下呼吸道感染病原菌耐药性严重,存在多重耐药性,在治疗中需要加强药物敏感试验,提高抗生素合理使用.     

Reactive oxygen species: a novel antimicrobial

The main solution to the global antibiotic resistance crisis is to reduce the volume of antibiotic use in medicine, agriculture and the environment. However, there is also a pressing need for novel antimicrobials. Despite much rhetoric, there are few entirely novel agents in development. One such therapy to reach clinical use is an agent using Reactive Oxygen Species (ROS), oxygen radicals, as an antimicrobial mechanism. ROS can be delivered to the site of infection in various formats. ROS are highly antimicrobial against Gram-positive and Gram-negative bacteria, viruses and fungi. They also prevent and break down biofilm. These functions make ROS potentially highly suitable for chronic inflammatory conditions, where antibiotics are frequently overused and relatively ineffective, including: chronic wounds, ulcers and burns; chronic rhinosinusitis, chronic bronchitis, bronchiectasis, cystic fibrosis and ventilated airways; recurrent cystitis; and prosthetic device infection. ROS could have an important role in infection prevention and antimicrobial stewardship. Much clinical investigation remains to be delivered on ROS therapy, but in vitro work on infection models and early clinical evaluations are extremely promising.     

重症寻常型天疱疮严重皮肤感染的病原学分析及抗菌药物治疗

目的探讨重症寻常型天疱疮合并严重皮肤感染病原菌和耐药性,找出敏感抗生素并及时联合激素应用,以提高临床治疗水平。方法随机选取2011年1月至2013年3月61例重症寻常型天疱疮患者为研究对象,对其中伴有严重皮肤感染39的患者进行病原菌和耐药性分析。结果对病原菌分布进行比较,共分离出病原菌52株,其中革兰阴性菌占全部病原菌48．08％,革兰阳性菌占全部病原菌30．77％,真菌占21．15％。在革兰阴性菌中耐药性较低的抗菌药物有利福平、亚胺培南,均为0,而在革兰阳性菌中耐药性较低的抗生素为替考拉宁、万古霉素,均为0,真菌中耐药性较低的抗生素为5-氟胞嘧啶、两性霉素B,均为0。经一系列对症治疗后总有效率为66．67％,死亡率20．51％。结论重症寻常型天疱疮合并严重皮肤感染病原菌较为均匀,选择敏感抗生素可提高临床效果。     

病原菌耐药性与抗菌药物消耗量相关性的研究进展

病原菌耐药性是指细菌使抗菌药物治疗作用下降的一种状态。耐药菌的出现使临床感染性疾病的治疗难度增加,抗菌药物的不合理使用是细菌耐药产生的主要原因,全国范围内或区域医疗机构内有效的抗菌药物管理策略,能够减少抗菌药物使用并逆转细菌耐药性的产生。国内外有关抗菌药物使用与病原菌耐药性相关性的研究较多,国内缺少对全国性或区域性的研究数据。通过综述近年来国内外有关金黄色葡萄球菌、粪肠球菌、屎肠球菌、大肠埃希菌、肺炎克雷伯菌、铜绿假单胞菌、鲍曼不动杆菌、阴沟肠杆菌及其他病原菌的耐药性与常用抗菌药物消耗量的相关性,从宏观数据上把握两者间的关系,以期为医院感染的管理提供证据支持。     

Antimicrobial resistance in foodborne pathogens--a cause for concern?

The widespread use of antibiotics in food animal production systems has resulted in the emergence of antibiotic resistant zoonotic bacteria that can be transmitted to humans through the food chain. Infection with antibiotic resistant bacteria negatively impacts on public health, due to an increased incidence of treatment failure and severity of disease. Development of resistant bacteria in food animals can result from chromosomal mutations but is more commonly associated with the horizontal transfer of resistance determinants borne on mobile genetic elements. Food may represent a dynamic environment for the continuing transfer of antibiotic resistance determinants between bacteria. Current food preservation systems that use a combination of environmental stresses to reduce growth of bacteria, may serve to escalate development and dissemination of antibiotic resistance among food related pathogens. The increasing reliance on biocides for pathogen control in food production and processing, heightens the risk of selection of biocide-resistant strains. Of particular concern is the potential for sublethal exposure to biocides to select for bacteria with enhanced multi-drug efflux pump activity capable of providing both resistance to biocides and cross-resistance to multiple antibiotics. Although present evidence suggests that biocide resistance is associated with a physiological cost, the possibility of the development of adaptive mutations conferring increased fitness cannot be ruled-out. Strategies aimed at inhibiting efflux pumps and eliminating plasmids could help to restore therapeutic efficacy to antibiotics and reduce the spread of antibiotic resistant foodborne pathogens through the food chain.     

住院患者临床分离菌菌群分布的随机监测分析

目的了解住院患者临床分离菌的分布及耐药情况，为指导临床合理用药提供参考依据。方法采用Vitek-2全自动微生物分析仪及纸片扩散法（Kirby-Bauer），对778株临床分离菌进行鉴定及药物敏感试验。结果778株分离菌中革兰阴性（G^-）杆菌占52．70％，革兰阳性（G^＋）球菌占35．60％，真菌占11．70％。G^＋球菌对万古霉素的敏感率均达100％，而G^-杆菌对碳青霉烯类抗生素的敏感率未达100％，其中铜绿假单胞菌对亚胺培南和美洛培南的耐药率分别为24．00％和18．67％，鲍曼不动杆菌对亚胺培南和美洛培南的耐药率均为4．76％。结论该资料对医院临床抗感染治疗及抗菌药物的选择有参考价值。     

Emerging antibacterial and antiviral drugs for treating respiratory tract infections

ABSTRACT

Introduction: Management of LRTI is becoming more frequently challenging since the emergence of multidrug resistance bacteria and the increase of severe viral infection, reducing the number of available effective drugs. The clinical evaluation of new therapeutic associations is mandatory to cope with the increases in resistance, in association with better infection control and antimicrobial policies.

Areas covered: We searched Pubmed in English language of phase I, II, III clinical trials and approved treatments for LRTI, between 2006 and 2016.

Expert opinion:Development of new molecules or new combinations regimens are very important for patients with severe infections and in specific subgroups of patients like CF and bronchiectatic patients. Standardized protocols for antibiotic stewardship in difficult-to-treat infections are the next step. Moreover, non-antibiotic treatments and preventive strategies as vaccination need to be part of clinical practice.     

儿科重症监护室下呼吸道感染常见病原菌分布及耐药分析

目的 探讨儿科重症监护室重症下呼吸道感染患儿痰液标本培养和药敏监测的意义.方法 回顾性分析1107例儿童重症监护室下呼吸道感染患儿痰液标本培养和药敏监测结果.结果 1107例标本共培养病原菌948株（85.64%）.其中G-菌616株（64.98%）中铜绿假单胞菌145株（15.30%）、肺炎克雷伯菌135株（14.24%）、鲍曼不动杆菌131株（13.82%）、大肠埃希菌89株（9.40%）;G＋菌129株（13.61%,主要以金黄色葡萄球菌为主）;真菌203株（21.41%,主要为白假丝酵母菌）.细菌主要敏感药物监测结果：G‘类为碳青霉烯类抗生素,G＋类为万古霉素.结论 重症患儿下呼吸道感染病原菌主要为G-菌,其次为G＋菌和真菌,感染菌对敏感抗生素具有高选择性,应根据药物敏感监测结果使用抗生素.     

尿路感染患者病原菌分布及耐药趋势分析

目的:分析我院尿路感染常见的病原菌分布及其对抗菌药物耐药情况,为临床合理使用抗菌药物提供科学依据。方法:收集我院2006年625份尿路感染尿液标本及其对分离出344株细菌进行培养及药敏试验。结果:G-杆菌最多(60·2%),G+球菌其次(33·4%),真菌最少(6·4%)。产超广谱β-内酰胺酶大肠埃希菌和肺炎克雷伯菌的检出率分别为49·2%和27·3%。细菌对各种抗菌药物有不同程度的耐药率,表现为多重耐药。结论:尿路感染应及时进行尿液细菌培养及药敏试验,慎重应用抗菌药物,以减少耐药菌的产生。     

ICU患者痰主要病原菌分布及耐药性分析

目的探讨引起重症监护（ICU）病区患者肺部感染的菌群分布及耐药性,为临床预防控制肺部院内感染及治疗提供直接可靠的参考依据。方法对ICU病区2007年1月至2008年12月期间痰标本分离培养出的主要病原菌分布及耐药性进行回顾性分析。结果痰培养分离出的病原菌以革兰氏阴性杆菌为主,首是鲍曼氏不动杆菌,依次顺序为铜绿假单胞菌、白色念珠菌、金黄色葡萄球菌、嗜麦芽窄食单胞菌、大肠埃希氏菌、肺炎克雷伯菌等。鲍曼氏不动杆菌、铜绿假单胞菌耐药率最高的是复方新诺明;白色念珠菌耐药率最高的是伊曲康唑;金黄色葡萄球菌耐药率最高的是青霉素;嗜麦芽窄食单胞菌对多种抗生素表现出高度耐药。结论革兰氏阴性杆菌仍是ICU病区肺部感染的主要菌群,特别是鲍曼氏不动杆菌,已成为ICU病区肺部感染的主要病原菌,且ICU肺部感染常呈交叉感染,因此预防肺部感染及交叉感染和降低耐药性已成为ICU病区当前的主要任务之一。