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肺炎克雷伯菌是什么

肺炎克雷伯菌是什么
肺炎克雷伯菌是什么

肺炎克雷伯菌是什么

*导读:肺炎克雷伯菌为革兰阴性杆菌,存在于人体上呼吸道和肠道,当机体抵抗力降低时,便经呼吸道进入肺内而引起大叶或小叶融合性实变,以上叶较为多见。……

肺炎克雷伯菌存在于人体上呼吸道和肠道,当机体抵抗力降低时,便经呼吸道进入肺内而引起大叶或小叶融合性实变,以上叶较为多见。

肺炎克雷伯杆菌是克雷伯菌属五个种菌属中主要对人致病的,大小为0.5-0.8μm×1-2μm,肺炎克雷伯杆菌为革兰阴性杆菌,有较厚的荚膜多数有菌毛,无芽孢和鞭毛。具有O抗原和K抗原。口咽部细菌的入侵引起肺部感染多见于年老体弱、营养不良、慢性酒精中毒、全身衰竭和原患慢性支气管-肺疾病等患者,呼吸道侵入性检查、污染的呼吸器、雾化器等的使用,以及免疫抑制性药物的应用均可成为引起感染的重要因素。

1简介

肺炎克雷伯菌为革兰阴性杆菌,病变中渗出液粘稠而重,致使叶间隙下坠。细菌具有荚膜,在肺泡内生长繁殖时,引起组织坏死、液化、形成单个或多发性脓肿。病变累及胸膜、心包时,可引起渗出性或脓性积液。病灶纤维组织增生活跃,易于机化;纤维素性胸腔积液可早期出现粘连。在院内感染的败血症中,克雷伯杆菌以及绿脓杆菌和沙雷氏菌等均为重要病原菌,病死率较

高。

及早使用有效抗生素是治愈的关键。首选氨基糖苷类抗生素,如庆大霉素、卡那霉素、妥布霉素、丁胺卡那霉素,可肌注、静滴或管腔内用药。重症宜加用头孢菌素如头孢孟多、头孢西丁、头孢噻肟等。哌拉西林,美洛西林与氨基糖苷类联用、左氧氟沙星疗效亦佳。部分病例使用氯霉素、四环素及SMZ-TMP亦有效。重症多有肺组织损伤,慢性病例有时需行肺叶切除。

2耐药机制

肺炎克雷伯菌(Kpn)是临床分离及医院感染的重要致病菌

之一,随着β-内酰胺类及氨基糖苷类等广谱抗菌素的广泛使用,细菌易产生超广谱β-内酰胺酶(ESBLs)和头孢菌素酶(AmpC 酶)以及氨基糖苷类修饰酶(AMEs),对常用药物包括第三代头

孢菌素和氨基糖苷类呈现出严重的多重耐药性。肺炎克雷伯菌引起的医院感染率近期逐年增高,且多耐药性菌株的不断增加常导致临床抗菌药物治疗的失败和病程迁延。肺炎克雷伯菌耐药机制主要包括产生β-内酰胺酶、生物被膜的形成、外膜孔蛋白的缺失。抗菌药物主动外排等,抗菌药物耐药基因水平播散是多药耐药菌株临床加剧的重要原因。

肺炎克雷伯杆菌肺炎

克雷白杆菌肺炎(Klebsiella pneumonia):近20余年来,该菌已成为院内获得性肺炎的主要致病菌,耐药株不断增加,且产生超广谱酶,成为防治中的难点。本病多见于中年以上男性,起病急、高热、咳嗽、痰多及胸痛,可有发绀、气急、心悸,约半数患者有畏寒,可早期出现休克。临床表现类似因为的肺炎球菌肺炎,但其痰常呈粘稠脓性,量多、带血,灰绿色或砖红色、胶冻状,但此类典型的痰液并不多见。胸部X线表现常呈多样性,包括大叶实变,好发于右肺上叶、双肺下叶,有多发性蜂窝状肺脓肿、叶间隙下坠。严重病例有呼吸衰竭、周围循环衰竭。慢性病程者表现为咳嗽、咳痰、衰弱、贫血等。克雷白杆菌肺炎的预后较差,病死率高。 临床表现:①发病骤起,出现呼吸困难; ②年长儿有大量黏稠血性痰,但婴儿少见; ③由于气道被黏液梗阻,肺部体征较少或完全缺乏; ④病情极为严重,发展迅速,患儿常呈休克状态; ⑤X线胸片示肺段或大叶性致密实变阴影,其边缘往往膨胀凸出。可迅速发展到 邻近肺段,以上叶后段及下叶前段较多见; ⑥常见并发症为肺脓肿,可呈多房性蜂窝状,日后形成纤维性变;其次为脓 胸及胸膜肥厚。治疗尚缺乏有效抗菌药物。 临床病理: 肺炎克雷白杆菌为革兰阴性杆菌,常存在于人体上呼吸道和肠道,当机体抵抗力 降低时,便经呼吸道进入肺内而引起大叶或小叶融合性实变,以上叶较为多见。病变中渗出液粘稠而重,致使叶间隙下坠。细菌具有荚膜,在肺泡内生长繁殖时,引起组织坏死、液化、形成单个或多发性脓肿。病变累及胸膜、心包时,可引起渗出性或脓性积液。病灶纤维组织增生活跃,易于机化;纤维素性胸腔积液可早期出现粘连。在院内感染的败血症中,克雷白杆菌以及绿脓杆菌和沙雷菌等均为重要病原菌,病死率较高。 老年体弱患者有急性肺炎、中毒症状严重、且有血性粘稠痰者,应考虑本病。确诊有赖于痰细菌学检查,并与葡萄球菌、结核菌或其他革兰阴性杆菌所致肺炎相鉴别。年老、白细胞减少、菌血症及原有严重疾病者预后较差。 与支气管扩张症区别 支气管扩张症是常见的慢性支气管化脓性疾病,大多数继发于呼吸道感染和支气 管阻塞,尤其是儿童和青年时期麻疹、百日咳后的支气管肺炎,由于破环支气管管壁, 形成管腔扩张和变形。 临床表现:慢性咳嗽伴大量脓痰和反复咯血。若有厌氧菌混合感染,则有臭味。 咯血可反复发生,程度不等,从小量痰血至大量咯血,咯血量与病情严重程度有时不 一致,支气管扩张咯血后一般无明显中毒症状。 与肺炎球菌肺炎区别 肺炎球菌肺炎是由肺炎球菌或肺炎链球菌所引起,占院外感染肺炎中的半数以上。肺段或肺叶呈急性炎性实变,临床上症状轻或不典型病较为多见。起病多急骤,有高热,体温在数小时内可以升到39-40℃,可呈稽留热,与脉率相平行。患侧胸部疼痛,可放射到肩部、腹部,咳嗽或深呼吸时加剧。痰少,可带血丝或呈铁锈色。胃纳锐减,偶有恶心、呕吐、腹痛或腹泻,有时误诊为急腹症。

肺炎克雷伯菌感染的护理与隔离措施

肺炎克雷伯菌感染的护理与隔离措施 [概述]肺炎克雷伯菌广泛存在于自然界以及正常人的呼吸道及肠道中,为条件致病菌,亦是医院内感染的重要致病菌。近年来,随着抗生素的应用,肺炎克雷伯杆菌的耐药性呈上升趋势肺炎克雷伯菌为革兰阴性杆菌,常存在于人体上呼吸道和肠道,机体抵抗力低下者容易感染。特别是早产儿,机体各组织器官功能尚未成熟,对外界环境的适应能力差,加上外界高危因素影响,更易感染该菌,且感染后发病迅速,病死率高。 [感染高危因素]由于新生儿特别是早产儿、极低体质量儿的免疫功能低下及侵入性操作的不断开展,肺炎克雷伯菌已成为新生儿感染的常见病原体,甚至在新生儿重症监护病房(NICU)暴发流行。同时,不洁的医疗操作和护理,创伤性治疗,特别是机械呼吸均可增加患儿院内获得性感染的机 会。由于重症监护病房(ICU)存在着患者住院时间长,交叉感染机会多,抗生素?激素广泛使用,侵 袭性操作多以及基础疾病严重等肺炎克雷伯菌感染的危险因素,因此,ICU是肺炎克雷伯菌感染的 高发区,故应加强对icu的监控,防止院内感染的发生? [耐药性]肺炎克雷伯菌对大部分头孢类抗生素及青霉素类药物均耐药,对头孢曲松、头孢吡肟、头孢噻吩、头孢噻肟、头孢唑啉、哌拉西林、氨苄西林的耐药率达96.5%~100%亚胺培南属碳青霉烯类抗生素,对B一内酰胺酶高度稳定,被认为是新生儿严重院内感染最有效抗生素。[护理与防治] 1.隔离患者,将患者单独至于隔离区,床旁张贴接触隔离要求。 2.指定专人护理,其余人员不得进入隔离区。 3.进入隔离区的医护人员必须严格执行接触隔离要求 ?工作人员进入隔离地带必须洗手-戴口罩-戴手套-穿隔离衣方可接触病人。 ?工作人员出隔离地带必须脱手套-脱隔离衣-洗手-脱口罩。 ?病人用过的被单、衣物等应单独清洗消毒,所用一次性物品(尿裤、奶瓶等),均用双层黄色 垃圾袋标记,按感染性废物处理。 4.医疗设备(监护仪、暖箱、辐射台、暖箱、蓝光箱、推注泵、吸氧装置、负压吸引装置、治 疗车、听诊器、软尺等)每天用1:80的84消毒液消毒,物品表面每天定时予1:80的84消毒液擦拭消毒,擦拭用的抹布一次性使用。 5.近年来文献报道吸氧装置及呼吸机管道受细菌污染日益增多,致病菌检出率高达20%_4 J, 若不及时消毒灭菌,很容易直接污染呼吸道而引起感染,所以必须加强对吸氧装置及呼吸机管道的定期更换消毒。 6.洗手医务人员接触患儿前后均严格规范洗手,再次强化各位医务人员的洗手意识。加强医护 人员的手部消毒及效果监测。 7.严格执行无菌操作对各种侵入性操作,如气管插管、插胃管、吸痰、洗胃、静脉输液等严格 遵守各项操作规程及无菌操作原则。 8.合理使用抗生素对合并感染者宜选用高效、低毒抗生素,并根据药物敏感试验有针对性地选 择一种抗生素治疗,严格控制三代头孢药物及高效、广谱抗菌药物的使用,避免长期使用抗生素而发生二重感染。 9.加强基础护理保持皮肤黏膜的完整是抗感染最有效的屏障,除常规护理外,发现微小的病灶 要及时处理。 10.呼吸道的管理新生儿肺部感染的发生几率较高,呼吸道的管理至关重要。患儿头肩部抬高 30。,并取右侧卧位以防分泌物或呕吐物吸入呼吸道而引起感染,经常清洁鼻腔,及时清理呼吸道分泌物,保持呼吸道通畅。

肺炎克雷伯菌研究进展

J OURNAL OF C LINICAL M ICROBIOLOGY,Aug.2007,p.2723–2725Vol.45,No.8 0095-1137/07/$08.00?0doi:10.1128/JCM.00015-07 Evaluation of Methods To Identify the Klebsiella pneumoniae Carbapenemase in Enterobacteriaceae? K.F.Anderson,*D.R.Lonsway,J.K.Rasheed,J.Biddle,B.Jensen,L.K.McDougal, R.B.Carey,A.Thompson,S.Stocker,B.Limbago,and J.B.Patel Centers for Disease Control and Prevention,Division of Healthcare Quality Promotion,Atlanta,Georgia Received3January2007/Returned for modi?cation13February2007/Accepted6June2007 The Klebsiella pneumoniae carbapenem(KPC)?-lactamase occurs in Enterobacteriaceae and can confer resistance to all?-lactam agents including carbapenems.The enzyme may confer low-level carbapenem resistance,and the failure of susceptibility methods to identify this resistance has been reported.Automated and nonautomated methods for carbapenem susceptibility were evaluated for identi?cation of KPC-mediated resistance.Ertapenem was a more sensitive indicator of KPC resistance than meropenem and imipenem independently of the method used.Carbapenemase production could be con?rmed with the modi?ed Hodge test. Carbapenems are commonly used to treat infections caused by multidrug-resistant Enterobacteriaceae.In the United States and other locations,an increasingly common mechanism of carbapenem resistance is the Klebsiella pneumoniae carbapen-emase(KPC)(2,10,15,18,19,24,26,27).The KPC?-lacta-mase occurs most commonly in K.pneumonia e,but it has also been reported sporadically in other species of Enterobacteria-ceae(Klebsiella oxytoca,Enterobacter spp.,Escherichia coli,Sal-monella spp.,Citrobacter freundii,and Serratia spp.)and Pseudomonas aeruginosa(4,10–12,17,23,28).The KPC en-zyme confers resistance to all?-lactam agents including peni-cillins,cephalosporins,monobactams,and carbapenems(1,21, 27,28).Some isolates containing KPC demonstrate low-level carbapenem resistance,but when combined with other cellular changes,such as porin loss,the carbapenem MIC increases (21,26).The gene encoding the KPC enzyme is usually?anked by transposon-related sequences and has been identi?ed on conjugative plasmids;therefore,the potential for dissemina-tion is signi?cant(17,26–28).Several outbreaks of KPC-pro-ducing bacteria have occurred in the northeast United States (2,26).Isolates that acquired this enzyme are usually resistant to several other classes of antimicrobial agents used as treat-ment https://www.wendangku.net/doc/883845912.html,boratory identi?cation of KPC-producing clinical isolates will be critical for limiting the spread of this resistance mechanism.The failure of automated susceptibility testing systems to detect KPC-mediated resistance was previ-ously noted(5,22). We evaluated commonly used susceptibility testing methods to identify the most sensitive conditions for KPC detection with31 KPC-producing Enterobacteriaceae isolates(25of K.pneumoniae, 2of K.oxytoca,1of E.coli,1of Enterobacter spp.,1of Citrobacter freundii,and1of Salmonella spp.).These were isolated from different patients who were hospitalized in13different healthcare institutions from seven different states:Maryland(one),New Jersey(two),New York(four),Pennsylvania(two),Michigan (two),Missouri(one),and North Carolina(one).The presence of bla KPC was determined using previously described oligonucleo-tide primers and cycling conditions(27).Enzyme activity was demonstrated in all isolates by isoelectric focusing(6,16). To measure the speci?city of methods to detect KPC-medi-ated resistance,45isolates(26of K.pneumoniae,9of K.oxy-toca,and10of E.coli)were chosen for testing.All45isolates were negative for bla KPC by PCR.These isolates were submit-ted to the CDC for reference susceptibility https://www.wendangku.net/doc/883845912.html,ing the reference broth microdilution(BMD)method,all isolates met the CLSI extended-spectrum?-lactamase(ESBL)screening test criteria;that is,they demonstrated reduced susceptibility to at least one extended-spectrum cephalosporin(7,8).Twenty-six isolates were positive by the CLSI ESBL broth con?rmatory test, and the other isolates were presumed to have another broad-spectrum?-lactamase or other mechanism of cephalosporin resistance.Five isolates were nonsusceptible to a carbapenem (imipenem,meropenem,or ertapenem)by BMD.Since two of the isolates were ESBL producers by BMD and the other three isolates produced an AmpC-type enzyme as demonstrated by isoelectric focusing and PCR(20),it is likely that the mechanism of reduced carbapenem susceptibility is a combination of a cepha-loporinase and porin loss(3,9,13). Meropenem,imipenem,and ertapenem susceptibilities were determined by BMD using cation-adjusted Mueller-Hinton broth in panels that were prepared in-house(7),disk diffusion(Becton Dickinson,Sparks,MD)(8),Etest(AB Biodisk,Piscataway,NJ), Microscan Autoscan using the NM32panel(Dade Behring,West Sacramento,CA),and the Vitek2test using the AST GN14card (bioMe′rieux,Durham,NC).Susceptibility testing of meropenem and imipenem was performed with the Phoenix test using the NEG MIC30panel or NEG MIC112panel(Becton Dickinson, Sparks,MD),the Vitek Legacy test using the GNS-122and GNS-127panels(bioMe′rieux,Durham,NC),and the Sensititre Auto Reader using the GN2F panel(Trek Diagnostics,West Lake, OH).All methods were performed according to the manufactur-ers’recommendations.Quality control testing of susceptibility *Corresponding author.Mailing address:Centers for Disease Con- trol and Prevention,Mail Stop G-08,1600Clifton Road NE,Atlanta, GA30333.Phone:(404)639-2824.Fax:(404)639-1381.E-mail:ebi2 @https://www.wendangku.net/doc/883845912.html,. ?Published ahead of print on20June2007. 2723 on August 19, 2015 by guest https://www.wendangku.net/doc/883845912.html,/ Downloaded from

关于肺炎克雷伯菌的临床分布与药敏结果

肺炎克雷伯菌的临床分布及耐药性 【摘要】目的了解我院临床分离肺炎克雷伯菌临床分布及耐药性。方法回顾性分析黄山市人民医院2010年10月-2011年10月间临床分离肺炎克雷伯菌对常用抗菌药物的耐药性,统计其临床分布。结果342株肺炎克雷伯菌主要来源于痰标本240株(占70.1%),尿液31株(占9.1%),血16株(占4.6%),分泌物14株(占4%),科室分布主要见于ICU110株(占32.2%),脑外52株(占15.2%),呼吸内科32株(占9.4%)药敏结果显示肺炎克雷伯菌对氨苄西林耐药率最高,达94.7%,对亚胺培南耐药率最低,仅为8.2%,厄他培南次之,耐药率为10.7%,对阿米卡星、妥布霉素、哌拉西林、头孢替坦、的耐药率分别为11.5%、13.5%、15.2%、16.1%,其余药物中,除环丙沙星(23.4%)外,对头孢唑林、胺苄西林、氨曲南、头孢匹美,庆大霉素、左旋氧氟沙星、复方新诺明、呋喃妥因、头孢他啶的耐药率均在30%以上。342株肺炎克雷伯菌中发现25株泛耐药菌株(占7.3%)。结论本院临床分离的肺炎克雷伯菌主要分离自痰液标本,以ICU、呼吸内科及脑外科为主,耐药性较为严重并存在泛耐药株。 【关键词】肺炎克雷伯菌抗生素耐药性 肺炎克雷伯菌属革兰阴性杆菌,常寄殖于呼吸道和肠道,是下呼吸道感染的重要病原菌,常引起典型的原发性肺炎及肺外感染,如肠炎、婴儿脑膜炎、败血症、泌尿系感染等。随着临床广谱抗生素的应用,肺炎克雷伯菌已经成为医院感染的重要病原菌,近年来肺炎克雷伯菌的感染率与耐药率明显升高,呈上升趋势。为进一步了解我院肺炎克雷伯菌耐药状况及临床分布,本研究针对2010.10-2011.10间临床分离的342株肺炎克雷伯菌进行耐药性分析,结果报道如下: 材料与方法 一、材料 (一)细菌收集我院2010.10~2011.10间临床分离的肺炎克雷伯菌株,共342株(剔除同一患者7天内同一部位的重复菌株),质控菌株为大肠埃希菌ATCC25922,铜绿假单胞菌ATCC27853,购自卫生部临检中心。 (二)仪器与试剂VITEK-2全自动微生物鉴定与药敏分析仪,NG鉴定卡,AST-NG药敏卡,VITEK比浊计购自法国Bio-Merieux公司;自制0.45%的生理盐水。 (三)药物种类AST-NG药敏卡带有氨苄西林、头孢唑林、胺苄西林、氨曲南、头孢匹美,庆大霉素、左旋氧氟沙星、复方新诺明、呋喃妥因、头孢他啶、哌拉西林,环丙沙星,阿米卡星、头孢替坦、亚胺培南、厄他培南、妥布霉素 (四)培养基细菌培养用中国蓝玫瑰酸琼脂粉,分纯培养用MH琼脂粉,均购自杭州

肺炎克雷伯杆菌肺炎

克雷白杆菌肺炎(Klebsiella pneumonia):近20余年来,该菌已成为院内获得性肺炎得主要致病菌,耐药株不断增加,且产生超广谱酶,成为防治中得难点、本病多见于中年以上男性,起病急、高热、咳嗽、痰多及胸痛,可有发绀、气急、心悸,约半数患者有畏寒,可早期出现休克。临床表现类似因为得肺炎球菌肺炎,但其痰常呈粘稠脓性,量多、带血,灰绿色或砖红色、胶冻状,但此类典型得痰液并不多见。胸部X线表现常呈多样性,包括大叶实变,好发于右肺上叶、双肺下叶,有多发性蜂窝状肺脓肿、叶间隙下坠、严重病例有呼吸衰竭、周围循环衰竭。慢性病程者表现为咳嗽、咳痰、衰弱、贫血等、克雷白杆菌肺炎得预后较差,病死率高。 临床表现:①发病骤起,出现呼吸困难; ②年长儿有大量黏稠血性痰,但婴儿少见; ③由于气道被黏液梗阻,肺部体征较少或完全缺乏; ④病情极为严重,发展迅速,患儿常呈休克状态; ⑤X线胸片示肺段或大叶性致密实变阴影,其边缘往往膨胀凸出、可迅速发展到邻近肺段,以上叶后段及下叶前段较多见; ⑥常见并发症为肺脓肿,可呈多房性蜂窝状,日后形成纤维性变;其次为脓胸及胸膜肥厚。治疗尚缺乏有效抗菌药物。 临床病理: 肺炎克雷白杆菌为革兰阴性杆菌,常存在于人体上呼吸道与肠道,当机体抵抗力降低时,便经呼吸道进入肺内而引起大叶或小叶融合性实变,以上叶较为多见。病变中渗出液粘稠而重,致使叶间隙下坠、细菌具有荚膜,在肺泡内生长繁殖时,引起组织坏死、液化、形成单个或多发性脓肿。病变累及胸膜、心包时,可引起渗出性或脓性积液。病灶纤维组织增生活跃,易于机化;纤维素性胸腔积液可早期出现粘连。在院内感染得败血症中,克雷白杆菌以及绿脓杆菌与沙雷菌等均为重要病原菌,病死率较高。 老年体弱患者有急性肺炎、中毒症状严重、且有血性粘稠痰者,应考虑本病。确诊有赖于痰细菌学检查,并与葡萄球菌、结核菌或其她革兰阴性杆菌所致肺炎相鉴别。年老、白细胞减少、菌血症及原有严重疾病者预后较差、 与支气管扩张症区别 支气管扩张症就是常见得慢性支气管化脓性疾病,大多数继发于呼吸道感染与支气管阻塞,尤其就是儿童与青年时期麻疹、百日咳后得支气管肺炎,由于破环支气管管壁,形成管腔扩张与变形。 临床表现:慢性咳嗽伴大量脓痰与反复咯血。若有厌氧菌混合感染,则有臭味。咯血可反复发生,程度不等,从小量痰血至大量咯血,咯血量与病情严重程度有时不一致, 支气管扩张咯血后一般无明显中毒症状。 与肺炎球菌肺炎区别 肺炎球菌肺炎就是由肺炎球菌或肺炎链球菌所引起,占院外感染肺炎中得半数以上、肺段或肺叶呈急性炎性实变,临床上症状轻或不典型病较为多见、起病多急骤,有高热,体温在数小时内可以升到39-40℃,可呈稽留热,与脉率相平行。患侧胸部疼痛,可放射到肩部、腹部,咳嗽或深呼吸时加剧。痰少,可带血丝或呈铁锈色。胃纳锐减,偶有恶心、呕吐、腹痛或腹泻,有时误诊为急腹症、 辅助检查:

肺炎克雷伯菌肺炎的临床诊治

【摘要】目的分析下呼吸道肺炎克雷伯杆菌感染的发病特点、药敏情况及治疗转归。了解产超广谱β-内酰胺酶(esbls)菌株耐药情况。方法回顾性分析37例肺炎克雷伯杆菌感染患者的临床特点、病原菌的耐药性、抗菌治疗及转归。结果该组病例以中老年患者为主,排菌及肺空洞形成占大多数,临床症状不典型,合并症及混合菌感染多,主要依靠病原学并结合临床、x线检查作为诊断依据.容易产esbls菌株,且有增长趋势,亚胺培南是首选抗感染用药。结论肺结核患者院内下呼吸道感染是一个值得关注的问题,警惕es-bls菌株的产生,治疗上应根据药敏联合应用抗生素. 【关键词】肺炎克雷白杆菌肺炎克雷伯杆菌(k1ebsiellapneumoniae),又称肺炎杆菌,是引起肺炎最多的革兰阴性杆菌,其所致的肺炎占细菌性肺炎的1%~5%,平均为2%,在社区获得性和医院获得性革兰阴性杆菌肺炎中分别18%~64%和30%,院内肺炎杆菌肺炎的发病约为6.6/10000~8.0/10000,肺炎杆菌占医院内肺炎全部病原体的7%~11%。虽有不少前瞻和回顾性调查,但肺炎杆菌在社会人群中的确切发病率甚难估计。近年来,随着对肺炎杆菌高效抗菌药物如第三代头孢菌素、氟喹诺酮类药物的不断问世与推广,和耐药严重的铜绿假单胞菌及其他假单胞菌、不动杆菌和阴沟杆菌等引起的肺炎比例增加,肺炎杆菌临床分离率有下降趋势。肺炎杆菌肺炎的病死率较高,为20%~50%,也有70%的报道,尤其在酗酒者。 1临床资料本组37例,其中男34例,女3例,年龄18~27岁。病程1~11d。临床表现:发热25例,咳嗽26例,咳浓痰20例,痰中带血7例,砖红色痰6例。肺部体征:湿啰音17例,干啰音4例。胸部x线检查:肺实变阴影6例,斑片状致密影有小空腔或空洞10例,肺纹理增多、紊乱,表现为支气管周围炎11例。实验室检查:白细胞总数高于正常15例,中性粒细胞&0.75的23例。 2诊断与鉴别诊断 2.1诊断男性,长期嗜酒,有慢性支气管炎或其他肺部疾病、糖尿病、恶性肿瘤、器官移植或粒细胞减少症等免疫抑制,或建立人工气道机械通气的患者,出现发热、咳嗽、呼吸困难及肺部湿啰音,外周血中性粒细胞增加,结合x线有肺部炎性浸润表现提示细菌性肺炎时,均应考虑肺炎杆菌的可能,特别是当青霉素或依托红霉素及其他大环内酰类抗生素治疗无效时。肺炎杆菌的临床表现、实验室和x线检查多不具有特征性。咯砖红色痰虽为其典型表现,但临床上并不多见。合格的痰标本涂片找见较多革兰阴性杆菌,尤其大量聚集在脓细胞和支气管的假复层纤毛柱状上皮细胞周围并带有荚膜者,更应考虑肺炎杆菌的可能,但此不是确诊依据。痰培养分离肺炎杆菌有利于诊断,但应与定植于口咽部的污染菌相鉴别。有认为连续两次以上经涂片筛选的痰标本分离到肺炎杆菌或定量培养分离的肺炎杆菌浓度≥109cfu/ml,可诊断为肺炎杆菌肺炎。对重症、难治或免疫抑制病例,使用防污染下呼吸道标本采样技术如经环甲膜穿刺气管吸引(ti’a)、防污染双套管毛刷采样(psb)、支气管肺泡灌洗(bal)和经皮穿刺吸引(la)等,从这些标本分离出肺炎杆菌则可确诊本病。 2.2鉴别诊断微生物学检查是确诊肺炎杆菌肺炎的惟一依据,也是与其他细菌性肺炎相鉴别的重要方法。 3治疗肺炎杆菌肺炎的治疗包括抗感染治疗和支持治疗。 3.1对症及支持治疗包括保持气道通畅、祛痰、止咳、给氧、纠正水、电解质和酸碱失衡、补充营养等。 3.2抗感染治疗及早使用有效抗生素是治愈的关键。在应用抗生素治疗前,肺炎杆菌感染的死亡率51%~97%;在抗生素治疗下,病死率已有明显下降。但由于肺炎杆菌耐药率较高,病死率为20%~30%,远超过肺炎链球菌肺炎。具有抗肺炎杆菌作用的抗菌药物较多,包括第一、第二和第三代头孢菌素、广谱青霉素、氨基糖苷类抗生素、氟喹诺酮类及其他,如亚胺培南和氨曲南等。高效、低毒、价廉是考虑选择抗菌药物的最重要因素。

产ESBLs肺炎克雷伯菌医院感染临床危险因素分析

产ESBLs肺炎克雷伯菌医院感染临床危险因 素分析 肺炎克雷伯菌是临床常见致病菌,其产超广谱β-内酰胺酶(ESBLs)株,由于对三代头孢等多种抗菌药物产生耐药性[1],常导致严重的医院感染,使抗感染治疗相当困难。研究产ESBLs肺炎克雷伯菌的临床特点和危险因素,是早期预防医院感染的关键。作者对一组呼吸系统感染产ESBLs肺炎克雷伯菌病例作一分析,结果报告如下。 1 资料与方法 1.1 对象 2003年1月至2005年12月,在本院住院治疗的患者,医院感染肺炎由产ESBLs肺炎克雷伯菌引起41例作为病例组,非产ESBLs 肺炎克雷伯菌引起59例作为对照组。医院感染肺炎诊断标准按文献相关标准[1,2],主要条件为咳嗽、咳痰,双侧或单侧肺有湿音或叩诊浊音,肺部X线胸片显示新的或进展性渗出病灶,次要条件有发热(体温≥38℃),周围血白细胞(WBC)≥10×109/L,深部痰细菌培养阳性。 1.2 方法

(1)流行病学调查:用统一表格,内容包括年龄、性别、住院时间、基础疾病、侵袭性治疗(气管切开或插管、留置导尿管、引流管、鼻饲管)、抗菌素使用等项目;住院时间为入院至分离鉴定出菌株的时间;抗菌素使用为分离鉴定出肺炎克雷伯菌株时的前15d情况。(2)标本采集:清晨嗽口后用力咳痰,立即送检,连续2~3d,或经吸痰管或气管插管吸引,或用防污染毛刷刷取痰液。合格标本为痰涂片镜检鳞状上皮细胞<10个/低倍镜视野和白细胞>25个/低倍镜视野或鳞状上皮细胞∶白细胞≤1∶2.5。(3)细菌鉴定、药敏及ESBLs检测:根据《全国临床检验操作规程》进行细菌学培养,采用英国先德荧光快速微生物鉴定/药敏分析系统,鉴定细菌及药敏试验用金黄色葡萄球菌ATCC25923、大肠埃希菌ATCC25922、铜绿假单胞菌ATCC27853及粪肠球菌ATCC33186进行质控;ESBLs菌株的确证试验根据美国临床实验室标准化委员会(NCCLS)规定,采用抗菌药物头孢噻肟/克拉维酸(30μg/10μg)与头孢噻肟抑菌圈直径差值、头孢他啶/克拉维酸(30/10μg)与头孢他啶抑菌圈差值来判断,当二种抗菌素中任何一种加克拉维酸后抑菌圈直径与不加克拉维酸的抑菌圈相比,增大值≥5mm时,判定为ESBLs阳性。用肺炎克雷伯菌ATCC700603进行质控。 1.3 统计学分析

肺炎克雷伯细菌及其荚膜

Klebsiella pneumoniae Bacteremia and Capsular Serotypes, Taiwan Chun-Hsing Liao, Yu-Tsung Huang, Chih-Cheng Lai, Cheng-Yu Chang, Fang-Yeh Chu, Meng-Shiuan Hsu, Hsin-Sui Hsu, and Po-Ren Hsueh Capsular serotypes of 225 Klebsiella pneumoniae isolates in Taiwan were identi ? ed by using PCR. Patients infected with K1 serotypes (41 isolates) had increased community-onset bacteremia, more nonfatal diseases and liver abscesses, lower Pittsburgh bacteremia scores and mortality rates, and fewer urinary tract infections than patients infected with non–K1/K2 serotypes (147 isolates). K lebsiella pneumoniae bacteria cause a variety of infections (1,2). Geographic differences in this organism have been recognized, and a high prevalence of liver abscesses has been observed for >20 years in persons in Taiwan infected with K . pneumoniae (3,4). K1 and K2 are the major capsular serotypes that cause liver abscesses and have increased virulence (4–7). In contrast, only limited information is available about serotypes causing K. pneumoniae bacteremia (3,5). Yu et al. grouped K1 and K2 serotypes and compared clinical characteristics for patients with K. pneumoniae bacteremia with those for patients infected with non–K1/K2 serotypes (3). Recent evidence suggests that K1 is a major cause of primary liver abscesses and has greater potential for causing metastasis, and that K2 is a major cause of secondary liver abscesses (6,8). We examined the distribution and clinical characteristics of serotypes that cause K. pneumoniae bacteremia from 225 patients (9) and performed PCR-based genotyping to identify capsular serotypes (10). The Study The study was conducted at Far-Eastern Memorial Hospital in Taipei, Taiwan. Patients with K . pneumoniae bacteremia were identi ? ed during January 1–December 31, 2007. Identi ? cation of K . pneumoniae was based on colony morphologic features and biochemical reactions (11). Data on time until positive blood culture results were obtained from the automated blood culture system at the hospital. Data for each patient were included only once (at the time of the ? rst detection of bacteremia). Patients <18 years of age and those not admitted to our hospital were excluded. Inactive malignancy was not included as an underlying illness. In-hospital and 14-day mortality rates were assessed. For 225 available bacterial isolates, cps genotyping was performed (10). A total of 231 patients with K . pneumoniae bacteremia were observed at the hospital during the study; 225 isolates from 225 patients were used. A total of 133 (59%) of these patients had community-onset bacteremia (bacteremia identi ? ed in an emergency department). The in-hospital mortality rate was 32.4%. Among 225 isolates, 41 (18.2%) were identi ? ed as K1 serotype, 37 (16.4%) as K2, 15 (6.7%) as K57, and 8 (3.6%) as K54. The K1 serotype was found predominantly in community-onset infections (36 [87.8%] of 41 patients compared with 75 [51.0%] of 147 patients infected with non–K1/K2 serotypes; odds ratio [OR] 6.91, 95% con ? dence interval [CI] 2.57–18.60) (online Appendix Table 1, https://www.wendangku.net/doc/883845912.html,/EID/content/17/6/1113-appT1.htm). Underlying illness was classi ? ed as nonfatal in 75.6% of patients with K1 bacteremia (53.7% of patients with non–K1/K2 bacteremia; OR 2.67, 95% CI 1.22–5.84). A lower percentage of patients with K1 bacteremia had surgery in the previous 3 months (9.8% vs. 30.6%; OR 0.25, 95% CI 0.09–0.73). Patients with K1 bacteremia had lower mean ± SD Pittsburgh bacteremia scores than those with non–K1/K2 bacteremia (2.7 ± 3.1 vs. 4.4 ± 4.7; OR 0.90, 95% CI 0.81–0.99), but the time until a positive blood culture was obtained was not different. K1 serotype was more common in patients with liver abscesses (46.3% vs. 4.1%; OR 20.3, 95% CI 7.31–56.40) and less common in patients with urinary tract infections (UTIs) (4.9% vs. 20.4%; OR 0.20, 95% CI 0.05–0.88). The in-hospital mortality rate for patients with K1 bacteremia was lower that that for patients with non–K1/K2 bacteremia (14.6% vs. 34.7%; OR 0.32, 95% CI 0.13–0.82). No differences were found in clinical characteristics for patients with K2 bacteremia and those with non–K1/K2 bacteremia except for a higher frequency of liver abscesses in patients with K2 bacteremia (13.5% vs. 4.1%; OR 3.67, 95% CI 1.06–12.8). For patients infected with K54 and K57 serotypes, 1 K57 serotype caused liver abscesses; no abscesses were found in patients infected with a K54 serotype. The in-hospital mortality rate was 50% (4/8) for patients with K54 bacteremia and 53.3% (8/15) for patients with K57 bacteremia. Patients infected with a K1 serotype had lower mean ± SD Pittsburgh bacteremia scores (2.7 ± 3.1 vs. 5.0 ± 5.3; Emerging Infectious Diseases ? https://www.wendangku.net/doc/883845912.html,/eid ? Vol. 17, No. 6, June 2011 1113 Author af ? liations: Far Eastern Memorial Hospital, Taipei, Taiwan (C.-H. Liao, C.-C. Lai, C.-Y . Chang, F.-Y . Chu, M.-S. Hsu, H.-S. Hsu); and National Taiwan University College of Medicine, Taipei (Y .-T. Huang, P .-R. Hsueh)DOI: 10.3201/eid1706.100811

肺炎克雷伯菌是什么

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