Carbapenem resistant Gram-negative bacteremia in an Indian intensive care unit: A review of the clinical profile and treatment outcome of 50 patients

Background:

Growing antimicrobial resistance and limited therapeutic options to treat carbapenem-resistant bacteremia prompted us to evaluate the clinical outcomes associated with healthcare-associated bacteremia.

Methods:

This was a retrospective observational study of carbapenem-resistant Gram-negative bacteremia performed at a tertiary care facility in Chennai, India between May 2011 and May 2012.

Results:

In our study, patients had mean 11.76 days of intensive care unit (ICU) care and mean time to onset of bacteremia was 6.4 days after admission. The commonest organism was Klebsiella pneumoniae (44%). Patients with combination treatment had lower mortality (44.8%) compared with colistin monotherapy (66.6%); (P = 0.35).

Conclusion:

Carbapenem resistant bacteremia is a late onset infection in patients with antibiotic exposure in the ICU and carries a 30 days mortality of 60%; K. pneumoniae is the most common organism at our center. Two drug combinations appear to carry a lower mortality compared with monotherapy.     

福建医科大学附属泉州第一医院儿科患者碳青霉烯类抗生素临床合理用药分析

目的评价福建医科大学附属泉州第一医院儿科住院患者碳青霉烯类抗生素的临床合理应用情况。方法回顾性分析2018年儿科96例患者碳青霉烯类抗生素的用药情况。结果共点评96例患者,男68例,女28例,中位年龄(四分位距)1.00(4.95)岁,中位体重(四分位距)9.00(17.33)kg;微生物送检94例,送检率为97.92%;细菌培养阳性32例,阳性率34.04%,分离菌株主要来源于静脉血和痰液,占70.00%;碳青霉烯类药物的中位用药天数(四分位距)为8.00(8.75)d。综合评价100分85例,90分3例,80分2例,0分6例。扣分项目包括适应证不符合,用法用量及配伍不当,使用抗菌药物前无相应的病原学检查,以及治疗过程中缺乏对疗效进行评估的动态实验室检查等。结论该院儿科住院患者碳青霉烯类抗生素应用基本合理,但临床科室需严格控制碳青霉烯类在感染患儿中的应用,强调病原学诊断,尽早实施目标性治疗。还应积极开展合理用药专项点评和临床培训,规范碳青霉烯类抗生素的应用。     

2016-2018年上海市第五人民医院细菌耐药性监测

目的分析2016-2018年上海市第五人民医院常见临床分离菌的分布及耐药情况,为临床合理选用抗菌药物提供依据。方法回顾性分析各类临床标本分离菌的分布及耐药性数据,依据CLSI 2018年标准判断结果,应用WHONET 5.6和SPSS 22.0进行统计分析。结果2016-2018年共检出7995株细菌,其中革兰阴性杆菌5737株,占71.8%,革兰阳性球菌2258株,占28.2%。未检出耐万古霉素和利奈唑胺的葡萄球菌,MRSA和MRCNS占各自菌种的33.2%~41.5%和67.7%~79.4%;MRSA对甲氧苄啶-磺胺甲[口恶]唑耐药率≤5.6%。耐万古霉素肠球菌的检出率为0.5%。青霉素不敏感的肺炎链球菌检出率为8.4%。大肠埃希菌、肺炎克雷伯菌和奇异变形杆菌中ESBL的检出率分别为54.4%、27.1%和44.7%。肠杆菌科细菌(克雷伯菌属除外)对碳青霉烯类、阿米卡星、哌拉西林-他唑巴坦和头孢哌酮-舒巴坦耐药率较低,均≤8.6%。克雷伯菌属、铜绿假单胞菌对亚胺培南和美罗培南的耐药率分别为25.5%和25.6%、19.5%和19.6%。鲍曼不动杆菌对大多数常用抗菌药物的耐药率接近或超过60%。流感嗜血杆菌β内酰胺酶的检出率儿童高于成人(48.4%对34.2%)。卡他莫拉菌β内酰胺酶检出率为98.5%。结论该院2016-2018年细菌耐药情况总体趋于平稳,但近年来细菌对碳青霉烯类抗菌药物耐药率呈上升趋势,应继续做好细菌耐药性监测工作,为临床合理使用抗菌药物提供可靠依据。     

In vitro and In vivo Fitness of Clinical Isolates of Carbapenem-Resistant and -Susceptible Acinetobacter baumannii

Context: Acinetobacter baumannii is one among the leading nosocomial pathogens in the healthcare settings worldwide. Limited data on relative fitness and virulence of carbapenem-resistant A. baumannii (CRAB) are known. New methods are required to curb the rapidly rising antimicrobial resistance of this bug. Aims: We aimed to study the comparative in vitro and in vivo fitness of clinical isolates of CRAB and carbapenem-susceptible A. baumannii (CSAB). Settings and Design: A total of nine A. baumannii isolates were included in this study. CSAB ATCC-19606 was taken as a reference control strain. Subjects and Methods: Matrix-assisted laser desorption ionisation–time of flight mass spectrometry and gyrB and bla_OXA-51 PCR were used for species identification. Antimicrobial susceptibility was performed using Kirby-Bauer disk-diffusion method. Minimum inhibitory concentration for carbapenems (imipenem, meropenem and doripenem) was determined using agar dilution method. End point analysis, competitive index (CI), growth kinetics and generation time were determined for CRAB and CSAB isolates. In vivo fitness of CRAB and CSAB was determined using Caenorhabditis elegans host model. Multilocus sequence typing was performed to see the genetic relatedness of the isolates under study. Results: End point analysis, in vitro CI and growth kinetics experiments showed better fitness of clinical isolates of CRAB over CSAB ones. In vivo ‘nematode fertility assay’ using C. elegans also supported the in vitro results. Conclusions: To the best of our knowledge, this is the first study of its kind from India showing difference in fitness of clinical isolates of CRAB and CSAB.     

重症监护室患者耐碳青霉烯类肺炎克雷伯菌感染危险因素分析

目的：了解重症监护室（ICU）中导致肺炎克雷伯菌感染患者耐碳青霉烯类抗菌药物的危险因素,为减少耐药菌的产生提供依据,以减少医院感染的发生。方法：收集某院2017-2018年ICU内经细菌培养鉴定为肺炎克雷伯菌的菌株,按药敏试验结果分为耐碳青霉烯肺炎克雷伯菌组（CRKP组,43例）和非耐碳青霉烯肺炎克雷伯菌组（KP组,109例）。统计每例患者基本情况、感染部位、住院时间、手术、首次检出阳性前抗菌药物使用情况等,分析其与耐碳青霉烯类肺炎克雷伯菌产生的相关性。结果：2组中均是痰标本中分离的占首位,其次是血液、尿液以及创面分泌物等。CRKP感染危险因素的单因素分析可见,患者高龄（P=0.032）,合并慢性肾功能不全（P=0.019）、恶性肿瘤（P=0.024）,患者机械通气时间、ApacheⅡ评分、感染部位个数是感染CRKP的危险因素（P<0.05）。首次检出CRKP/KP前,患者接受碳青霉烯类或者喹诺酮类药物治疗（P<0.001）是CRKP感染的危险因素。非线性Logstic回归分析显示,患者年龄、住院时间、合并恶性肿瘤、感染部位个数、机械通气时间、ApacheⅡ评分,接受碳青霉烯类、喹诺酮类治疗为CRKP感染的独立危险因素（P<0.05）。结论：应进一步规范碳青霉烯类及喹诺酮类药物的使用,同时针对危险因素高的患者做好有效医院感染预防控制措施,以减少耐碳青霉烯类肺炎克雷伯菌医院感染的发生,延缓耐碳青霉烯类肺炎克雷伯菌的传播。     

Infection with Klebsiella pneumoniae carbapenemase (KPC)-producing K. pneumoniae in solid organ transplantation

Klebsiella pneumoniae carbapenemase (KPC)‐producing K. pneumoniae is spreading globally and represents a challenge in infection control and treatment. Solid organ transplant (SOT) recipients are especially at risk for infection by multidrug‐resistant bacteria, and little is known about infection with KPC‐producing organisms in this setting. The aim of this study was to describe the clinical and microbiologic aspects of KPC‐producing K. pneumoniae infections in SOT recipients. A KPC‐2‐producing K. pneumoniae outbreak was identified in a public teaching tertiary care hospital in São Paulo, Brazil, in June 2009. During the outbreak, cases of KPC‐2‐producing K. pneumoniae infection in SOT recipients occurred between July 2009 and February 2010; these cases were retrospectively reviewed. Overall, 12 episodes of infection with KPC‐producing K. pneumoniae occurred in 2 heart, 4 liver, and 6 kidney transplant recipients with incidence rates of 16.7%, 12.9%, and 26.3% in heart, liver, and kidney transplantation, respectively. Infection occurred at a median time of 20 days after transplantation. Primary infection sites were as follows: 4 urinary tract infections, 4 bloodstream infections, 2 pneumonias, and 2 surgical site infections. All patients except one had received antibiotics in the last 30 days, mostly piperacillin‐tazobactam or glycopeptides. All strains exhibited susceptibility to amikacin and gentamicin. Patients were treated with tigecycline plus polymyxin B (3 cases), polymyxin B plus carbapenem (3 cases), polymyxin B alone (3 cases), or tigecycline plus imipenem (1 case). In 2 cases, patients received only carbapenem, and death occurred before the final culture result. The overall 30‐day mortality rate was 42%. In this series of KPC‐producing K. pneumoniae infection in SOT recipients, the infection occurrence was high during an institutional outbreak and was potentially life threatening.     

河北以岭医院6种重点监测耐药菌的分布特点及耐药分析

目的 分析河北以岭医院2018—2020年6种重点监测耐药菌的分布特点及耐药性,为临床控制感染及规范用药提供理论依据。方法 回顾性分析2018—2020年住院患者分离的6种重要耐药菌,包括耐碳青霉烯类大肠埃希菌（CREC）、耐碳青霉烯类肺炎克雷伯菌（CRKP）、耐碳青霉烯类铜绿假单胞菌 （CRPAE）、耐碳青霉烯类鲍曼不动杆菌（CRAB）、耐甲氧西林金黄色葡萄球菌（MRSA）和耐万古霉素肠球菌（VRE）的分布情况及耐药特点;并采用改良碳青霉烯灭活（mCIM）试验和EDTA改良碳青霉烯灭活（eCIM）试验进行93株耐碳青霉烯类肠杆菌目细菌（CRE）菌株的酶型检测。结果 连续3年共检出CREC 9株、CRKP 253株、CRAB 252株、CRPAE 227株、MRSA 99株、VRE 9株。主要集中在重症监护室、肺病科、神经外科等科室;主要检出标本类型为呼吸道标本,其次为尿液标本、分泌物标本等。mCIM和eCIM试验结果显示,86株CRKP菌株中,mCIM阳性81株;mCIM和eCIM同时阳性即金属酶阳性菌株15株（17.4%）;mCIM阳性和eCIM阴性即丝氨酸酶阳性菌株66株（76.7%）;7株CREC菌株中mCIM和eCIM全部阳性。结论 临床耐药菌株日益增多,尤其是CRE和CRPAE菌株,使临床抗感染治疗面临严峻的挑战,应积极采取有效防控措施,加强耐药菌感染的预防和控制,提高诊疗能力建设,遏制耐药菌的流行播散。     

弗劳地枸橼酸杆菌中质粒介导的KPC-2和NDM-1型碳青霉烯酶基因结构分析

目的对携带bla_(NDM-1)和bl_(aKPC-2)的弗劳地枸橼酸杆菌的碳青霉烯酶基因结构进行分析。方法收集4株耐碳青霉烯类药物弗劳地枸橼酸杆菌(CF-05、CF-17、CF-35、CF-43),琼脂稀释法测定抗菌药物敏感性;脉冲场凝胶电泳(PFGE)分析细菌同源性;特异性PCR扩增和序列测定分析碳青霉烯酶耐药基因和ESBLs耐药基因、接合试验、耐药基因周围序列分析对菌株的耐药机制进行分子水平研究。结果 4株细菌仅CF-05对阿米卡星敏感,所有菌株对其他检测药物全部耐药;PFGE结果显示4株细菌不同源;特异性PCR扩增和序列分析显示2株(CF-35、CF-43)同时携带blaNDM-1和blaKPC-2、另2株(CF-05、CF-17)仅携带blaNDM-1,CF-35同时携带bla_(CTX-M-15);其中3株细菌(CF-05、CF-17、CF-43)接合成功,CF-05、CF-17接合子(CF-05-1和CF-17-1)携带bla_(NDM-1),CF-43获得2种接合子(CF-43-1携带bla_(KPC-2)、CF-43-2同时携带bla_(NDM-1)和bla_(KPC-2));分析blaNDM-1和blaKPC-2周围序列发现,4株细菌周围序列分别与国内报道携带bla_(NDM-1)和bla_(KPC-2)的肺炎克雷伯菌质粒pNDM-HN380和PK048周围序列高度相似。结论在4株弗劳地枸橼酸杆菌中检测到NDM-1型碳青霉烯酶,其中2株同时携带KPC-2型碳青霉烯酶,bla_(NDM-1)周围序列和bla_(KPC-2)周围序列与国内已知肺炎克雷伯菌相关耐药基因周围序列高度相似。