血培养-临床医生应该知道什么-PPT.pptx

血培养-临床医生应该知道什么Conflicts of InterestSpeaker fee or consultation fee from the following pharmaceutical companiesGSKEli lillyPfizerSanofi-AventisXian JasenMSDBayerWyeth危重病患者的全身性感染全身性感染9%细菌学证实71%菌血症56%Brun-Buisson C,Doyon F,Carlet J,et al.Incidence,risk factors,and outcome of severe sepsis and septic shock in adults:a multicenter prospective study in intensive care units;French ICU Group for Severe Sepsis.JAMA 1995;274:968-974 血行性感染:概述在医院获得性感染中所占比例逐渐增加 200,000例血行性感染/年病死率40 50%血行性感染的致病菌分离株比例致病菌美国1芬兰2凝固酶阴性葡萄球菌31.9%31%金黄色葡萄球菌15.7%11%肠球菌11.1%6%念珠菌属7.6%4%大肠杆菌5.7%11%克雷白菌属5.4%5%肠杆菌属4.5%3%假单胞菌属4.4%5%沙雷氏菌属1.4%草绿色链球菌1.4%5%1.Michael B.Edmond,Sarah E.Wallace,Donna K.McClish,et al.Nosocomial Bloodstream Infections in United States Hospitals:A Three-Year Analysis.Clin Infect Dis 1999;29:239-44.2.Lyytikainen O,Lumio J,Sarkkinen H,et al.Nosocomial Bloodstream Infections in Finnish Hospitals during 19992000.Clin Infect Dis 2002;35:e14-9血培养:临床意义Perez A,Herranz M,Segura M,et al.Epidemiologic impact of blood culture practices and antibiotic consumption on pneumococcal bacteraemia in children.Eur J Clin Microbiol Infect Dis 2008;27:717-724Navarre vs.Majorca(2000 2004)Occult bacteraemiaRR 11.8(4.7 29.7)Bacteraemic pneumoniaRR 2.6(1.5 4.4)MeningitisRR 0.8(0.2 2.8)大家有疑问的，可以询问和交流大家有疑问的，可以询问和交流可以互相讨论下，但要小声点可以互相讨论下，但要小声点可以互相讨论下，但要小声点可以互相讨论下，但要小声点血培养:临床意义200220032004NavarreAmox376358385Amox/Clav370366356Oral Ceph277268240Clari978270Azi225208169MajorcaAmox383363365Amox/Clav387400428Oral Ceph420412347Clari145140111Azi241230206Perez A,Herranz M,Segura M,et al.Epidemiologic impact of blood culture practices and antibiotic consumption on pneumococcal bacteraemia in children.Eur J Clin Microbiol Infect Dis 2008;27:717-724PCG-REry-R0%10%20%30%40%50%60%Navarre,PCG-R,32.6%Navarre,Ery-R,30.3%Majorca,PCG-R,54.3%Majorca,Ery-R,45.7%NavarreMajorca内容鉴别菌血症患者提高血培养阳性率识别致病菌与污染菌 菌血症的预测指标菌血症与非菌血症患者的血流动力学、临床和实验室指标变量均值P 值非菌血症(n=268)菌血症(n=197)体温,F100.7(2.9)101.1(3.1)0.22呼吸频率呼吸频率,bpm31(10)31(10)29(9)29(9)0.0470.047PaCO2,mmHg33(11)31(9)0.051脉搏,bpm118(17)118(19)0.64收缩压收缩压,mmHg104(30)104(30)95(31)95(31)0.0020.002白细胞计数,x 10918(16)17(10)0.42中性粒细胞,%67(22)65(22)0.30未成熟中性粒细胞未成熟中性粒细胞,%,%17(17)17(17)21(16)21(16)0.020.02血小板计数血小板计数,x 103279(186)279(186)219(145)219(145)0.00010.0001Peduzzi P,et al.Predictors of bacteremia and Gram-negative bacteremia in patients with sepsis.Arch Intern Med 1992;152:529-535 菌血症的预测指标逻辑回归分析结果预测因素系数标准误2P 值体温体温,线性线性-3.683-3.6831.1841.1844.024.020.0450.045体温体温,二次二次0.0190.0190.0090.0094.164.160.0410.041呼吸频率-0.0210.0113.410.065PaCO2-0.0170.0102.620.105脉搏0.0030.0060.240.625收缩压收缩压-0.010-0.0100.0030.0039.269.260.0020.002白细胞计数-0.0010.0070.010.942中性粒细胞计数0.0040.0050.490.484未成熟中性粒细胞计数0.0130.0073.400.065血小板计数血小板计数-0.002-0.0020.0010.0018.358.350.0040.004Peduzzi P,et al.Predictors of bacteremia and Gram-negative bacteremia in patients with sepsis.Arch Intern Med 1992;152:529-535菌血症:预测指标主要标准次要标准(每项1分)怀疑心内膜炎(3分)体温 39.4C(103.0F)(3分)留置血管内导管(2分)体温38.3 39.3C(101.0 102.9F)年龄 65岁寒战呕吐低血压(收缩压 18,000杆状核 5%血小板 20 mg/dLShapiro NI,Wolfe RE,Wright SB,et al.Who needs a blood culture?A prospectively derived and validated prediction rule.J Emerg Med 2008;35(3):255-264菌血症:预测指标RiskBacteremiaLow(0-1)Moderate(2-5)High(5)0%5%10%15%20%25%30%Derivation,Low(0-1),0.6%Derivation,Moderate(2-5),6.8%Derivation,High(5),26.0%Validation,Low(0-1),0.9%Validation,Moderate(2-5),9.1%Validation,High(5),15.4%DerivationValidationShapiro NI,Wolfe RE,Wright SB,et al.Who needs a blood culture?A prospectively derived and validated prediction rule.J Emerg Med 2008;35(3):255-264鉴别菌血症患者发热是重要的临床指标BT 38.5C,低体温,白细胞增加,低血压,意识障碍警惕体温正常的菌血症鉴别引起体温升高的其他疾病内科危重病患者更为复杂Shafazand S,Weinacker AB.Blood cultures in the critical care unit.Chest 2002;122:1727-1736内容鉴别菌血症患者提高血培养阳性率识别致病菌与污染菌血培养阳性率的影响因素血液屏障细菌数量少间断性菌血症血液成分中的杀菌机制(溶酶体,补体,中性粒细胞,抗体)临床和实验室因素采血量抗生素使用血培养数目血培养时机培养时间培养环境培养基Shafazand S,Weinacker AB.Blood cultures in the critical care unit.Chest 2002;122:1727-1736提高血培养阳性率的措施Shafazand S,Weinacker AB.Blood cultures in the critical care unit.Chest 2002;122:1727-1736留取血培养前应对皮肤进行充分消毒避免仅留取一套血培养;24小时内应在不同静脉穿刺部位留取2或3套培养(包括需氧和厌氧瓶)每个培养瓶应至少留取10 mL血标本如从静脉导管留取血标本,应同时经外周静脉留取,以帮助鉴别污染菌及真正的致病菌应根据临床情况及微生物实验室的建议使用适当的培养基和收集系统如有可能,应在应用抗生素前留取血标本.如果已经使用抗生素,当抗生素血药浓度达到谷值时留取培养可能提高阳性率提高血培养阳性率何时留取血培养皮肤消毒穿刺部位留取血培养次数留取血标本量送检时间是否需要常规留取厌氧培养采集血培养的时机菌血症发生1 2小时后出现发热寒战1培养的时机体温高峰后尽早留取血培养临床研究结果不支持21.Chandrasekar PH,Brown WJ.Clinical issues of blood cultures.Arch Intern Med 1994;154:841-8492.Li J,Plorde JJ,Carlson LG.Effects of volume and periodicity on blood cultures.J.Clin.Microbiol 1994;32:2829-31.抗生素治疗前后血培养的阳性率139139名患者名患者抗生素治疗前抗生素治疗前抗生素治疗过程中抗生素治疗过程中开始抗生素治疗开始抗生素治疗8383名患者名患者(60%)血培养阴性或血培养阴性或分离出污染菌分离出污染菌0/83(0%)0/83(0%)分离到致病菌分离到致病菌5656名患者名患者(40%)分离到致病菌分离到致病菌26/56(45%)26/56(45%)分离到致病菌分离到致病菌2525名患者名患者(45%)分离到致分离到致病的葡萄球菌病的葡萄球菌19/25(76%)19/25(76%)分离到葡萄球菌分离到葡萄球菌1414名患者名患者(25%)分离到致分离到致病的链球菌病的链球菌5/14(36%)5/14(36%)分离到链球菌分离到链球菌1717名患者名患者(30%)分离到革分离到革兰阴性杆菌兰阴性杆菌2/17(12%)2/17(12%)分离到革兰阴性杆菌分离到革兰阴性杆菌1/139(0.72%)1/139(0.72%)分离到新的致病菌分离到新的致病菌Grace CJ,Lieberman J,Pierce K,et al.Usefulness of Blood Culture for Hospitalized Patients Who Are Receiving Antibiotic Therapy.Clin Infect Dis 2001;32:1651-5 临床意义应用抗生素前进行血培养分离到致病菌的可能性增加2.2倍在开始抗生素治疗最初72小时内,连续进行血培养的结果,可以根据应用抗生素前血培养的结果预测极少分离到新的致病菌医生可以等待应用抗生素前的血培养结果回报后,再进行新的血培养Grace CJ,Lieberman J,Pierce K,et al.Usefulness of Blood Culture for Hospitalized Patients Who Are Receiving Antibiotic Therapy.Clin Infect Dis 2001;32:1651-5血培养:留取血标本的时机对于血流动力学不稳定的患者,应当在应用抗生素前留取2套血培养Shafazand S,Weinacker AB.Blood cultures in the critical care unit.Chest 2002;122:1727-1736应用抗生素后的血培养应当在抗生素达到谷浓度时留取血培养未经过深入研究缺乏临床实用性Chandrasekar PH,Brown WJ.Clinical issues of blood cultures.Arch Intern Med 1994;154:841-849Mylotte JM,Tayara A.Blood cultures:clinical aspects and controversies.Eur J Clin Microbiol Infect Dis 2000;19:157-163吸附抗生素的血培养瓶Flayhart D,Borek AP,Wakefield T,et al.Comparison of BACTEC PLUS blood culture media to BacT/Alert FA blood culture media for detection of bacterial pathogens in samples containing therapeutic levels of antibiotics.J Clin Microbiol 2007;45(3):816-8210时间点时抗生素种类时间点时抗生素种类BACTEC PLUS浓度浓度 g/ml(%)BacT/Alert FA浓度浓度 g/ml(%)万古霉素无0(0)0(0)谷值(10 g/mL)0(0)8.8(88)中值(25 g/mL)0(0)22.5(90)峰值(50 g/mL)15(30)36(72)头孢西丁无 10(0)10(0)中值(60 g/mL)10(0)43(71)峰值(110 g/mL)95%间断菌血症阳性率 85%污染菌阳性阳性率 5%后续血培养阳性率 1%Shafazand S,Weinacker AB.Blood cultures in the critical care unit.Chest 2002;122:1727-1736血培养次数Shafazand S,Weinacker AB.Blood cultures in the critical care unit.Chest 2002;122:1727-1736多数情况下,24小时内无需留取超过2 3套血培养从2 3个不同部位留取血标本应当留取1次以上的血培养有助于鉴别真正菌血症和细菌污染采集血培养的次数血培养之间的时间间隔并不明确同时,间隔2小时,间隔24小时采血并无差异Li J,Plorde JJ,Carlson LG.Effects of volume and periodicity on blood cultures.J Clin Microbiol 1994;32:2829-2831采集血培养的方法:采血量成人菌血症时血液中细菌密度 103 cfu/mL推荐留取20 30 ml血液血标本每增加1 ml,培养检出率增加3%Mermel LA,Maki DG.Detection of bacteremia in adults:consequences of culturing an inadequate volume of blood.Ann Intern Med 1993;119:270-272血培养:采血量The higher the volume of blood cultured the higher the yield of blood cultures Washington II JAWashington JA.Blood cultures:principles and techniques.Mayo Clin Proc 1975;50:91-95Washington JA.Evolving concepts on the laboratory diagnosis of septicemia.Infect Dis Clin Pract 1993;2:65-69Washington JA II,Ilstrup DM.Blood cultures:issues and controversies.Rev Infect Dis 1986;8:792-802血培养:采血量Donnino MW,Goyal N,Terlecki TM,et al.Inadequate blood volume collected for culture:a survey of health care professionals.Mayo Clin Proc 2007;82(9):1069-1072血培养:采血量Donnino MW,Goyal N,Terlecki TM,et al.Inadequate blood volume collected for culture:a survey of health care professionals.Mayo Clin Proc 2007;82(9):1069-107279%10 mLMean(SD)6.0(9.0)mLMedian(IQR)5(2,5)mL血培养:采血量Donnino MW,Goyal N,Terlecki TM,et al.Inadequate blood volume collected for culture:a survey of health care professionals.Mayo Clin Proc 2007;82(9):1069-1072血培养:采血量Donnino MW,Goyal N,Terlecki TM,et al.Inadequate blood volume collected for culture:a survey of health care professionals.Mayo Clin Proc 2007;82(9):1069-1072结论大部分医务人员不了解血培养时推荐的最佳采血量血培养:采血量与阳性率Bouza E,Sousa D,Rodriguez-Creixems M,et al.Is the volume of blood cultured still a significant factor in the diagnosis of bloodstream infections?J Clin Microbiol 2007;45(9):2765-2769OR 0.98795%CI 0.976 0.998P 0.018OR 1.0495%CI 1.001 1.08P 0.018血培养:采血量Weinstein MP,Mirrett S,Wilson ML,et al.Controlled evaluation of 5 versus 10 milliliters of blood cultured in aerobic BacT/Alert blood culture bottles.J Clin Microbiol 1994;32(9):2103-2106血培养:培训的重要性Connell TG,Rele M,Cowley D,et al.How reliable is a negative blood culture result?Volume of blood submitted for culture in routine practice in a Childrens hospital.Pediatr 2007;119:891-896干预前干预前干预后干预后采血量,mL 中位数(范围)1.75(0.0 20.1)2.12(0.2 20.6)采血量足够*491/1067(46.0%)186/291(63.9%)送检正确*378/491(77.0%)149/186(80.1%)血培养正确比例378/1067(35.4%)149/291(51.2%)*采血量足够指1个月龄以下 0.5 mL,1 36个月龄者 1.0 mL，36个月龄者 4.0 mL*若采血量 1周(19.6 1.6 days)85%接受输血治疗(9.5 0.8 U)静脉采血解释输血量差异的49%采血量采血量,mL输血输血总计总计每日每日无601 7740 51 5 U858 5961 4 5 U1708 13768 6 10 U2156 20870 6Corwin HL,Parsonnet KC,Gettinger A.RBC transfusion in the ICU.Chest 1995;108:767-771危重病患者的贫血设计:前瞻性观察研究背景和患者:西欧145个ICU的1136名患者结果:最初24小时内采血次数4.6(3.2)次45.9%的患者采血 5次采血量10.3(6.6)ml/次24小时内采血量41.1(39.7)mLSOFA评分与采血次数(r=0.34;p 0.001)及采血量(r=0.28;p 0.001)相关Vincent JL,Baron JF,Reinhart K,et al.Anemia and blood transfusion in critically ill patients.JAMA 2002;288(12):1499-1507 血培养的技术细节:采血量理论上6个培养瓶,总量35 42 mL,最好为同时取血1实际2或3个培养瓶,每次抽血20 30 mL2,3缺乏实际可操作性1.Lamy B,Roy P,Carret G,et al.What is the relevance of obtaining multiple blood samples for culture?A comprehensive model to optimize the strategy for diagnosing bacteremia.Clin Infect Dis 2002;35:842-50.2.Washington JA,Ilstrup DM.Blood cultures:issues and controversies.Rev Infect Dis 1986;8:792-802.3.Wilson ML,Weinstein MP.General principles in the laboratory detection of bacteremia and fungemia.Clin Lab Med 1994;14:69-82.血培养:标本运送与处理时间血培养运送时间不超过4小时1实际平均运送时间为10.4小时21.Garcia,L.S.(ed.).2007.2007 update:clinical microbiology procedures handbook,2nd ed.ASM Press,Washington,DC.2.Kerremans JJ,Verboom P,Stijnen T,et al.Rapid identification and antimicrobial susceptibility testing reduce antibiotic use and accelerate pathogendirected antibiotic use.J.Antimicrob.Chemother.2008;61:428-435血培养:标本运送时间影响因素Kerremans JJ,van der Bij AK,Goessens W,et al.Needle-to-incubator transport time:logistic factors influencing transport time for blood culture specimens.J Clin Microbiol 2009;47(3):819-822 OR(95%CI)p往返距离4分钟内1 0.0014 8分钟0.80（0.69 0.84）其他0.26（0.15 0.45）每日查房次数10.85(0.75 0.97)0.0012130.40(0.28 0.56)标本采集日工作日10.017周末0.92(0.85 0.98)专科外科1.2.2.08.08.19.19.02.02DesJardin JA,Falagas ME,Ruthazer R,et al.Clinical utility of blood cultures drawn from indwelling central venous catheters in hospitalized patients with cancer.Ann Intern Med 1999;131:641-647.能否从中心静脉插管取血进行培养中心静脉插管取血培养若阳性,需要进行细致的临床判断和确认通过导管取血进行培养可以作为除外血行性感染的方法DesJardin JA,Falagas ME,Ruthazer R,et al.Clinical utility of blood cultures drawn from indwelling central venous catheters in hospitalized patients with cancer.Ann Intern Med 1999;131:641-647.血行性感染的常见致病菌细菌细菌明确感染明确感染%细菌污染细菌污染%不确定不确定%金黄色葡萄球菌87.26.46.4大肠杆菌99.3007凝固酶阴性葡萄球菌12.481.95.8肺炎克氏菌100.000肠球菌69.916.114.0铜绿假单胞菌96.41.81.8肺炎链球菌100.000白色念珠菌90.0010.0草绿色念珠菌38.049.312.7阴沟肠杆菌100.000 如何鉴别真正的致病菌和污染菌常见致病菌(95%)金黄色葡萄球菌大肠杆菌肠杆菌铜绿假单胞菌肺炎链球菌白色念珠菌常见污染菌(5%)棒状杆菌属芽孢杆菌属疮疱丙酸杆菌Towns ML,Quartey SM,Weinstein MP,et al.The clinical significance of positive blood cultures:a prospective,multicenter evaluation,abstr.C-232.In Abstracts of the 93rd General Meeting of the American Society for Microbiology 1993.American Society for Microbiology,Washington,D.C.Weinstein MP,Towns ML,Quartey SM,et al.The clinical significance of positive blood cultures in the 1990s:a prospective comprehensive evaluation of the microbiology,epidemiology,and outcome of bacteremia and fungemia in adults.Clin Infect Dis 1997;24:584-602.血培养:常见污染菌Geffers C,Farr BM.Positive predictive value of a percutaneously drawn blood culture growing skin flora varies markedly by organism.Infect Control Hosp Epidemiol 2005;26(6):507-509 鉴别困难的分离株Towns ML,Quartey SM,Weinstein MP,et al.The clinical significance of positive blood cultures:a prospective,multicenter evaluation,abstr.C-232.In Abstracts of the 93rd General Meeting of the American Society for Microbiology 1993.American Society for Microbiology,Washington,D.C.Weinstein MP,Towns ML,Quartey SM,et al.The clinical significance of positive blood cultures in the 1990s:a prospective comprehensive evaluation of the microbiology,epidemiology,and outcome of bacteremia and fungemia in adults.Clin Infect Dis 1997;24:584-602.真正菌血症的比例(%)草绿色链球菌38%肠球菌78%凝固酶阴性葡萄球菌15%多种细菌培养阳性血行性感染通常为单一致病菌血培养分离出多种细菌可能为污染菌6 21%的菌血症为多种细菌引起尤其在高危患者不能仅仅根据血培养分离多种细菌判定为污染菌血培养阳性次数污污染率染率至少两套血培养阳性两套血培养仅一套阳性仅一套血培养阳性0%20%40%60%80%Series1,至少两套血培养阳性,27.8%Series1,两套血培养仅一套阳性,75.2%Series1,仅一套血培养阳性,66.9%PPVPPV仅一套血培养两套血培养三套血培养0%20%40%60%Series1,仅一套血培养,55%Series1,两套血培养,20%Series1,三套血培养,5%Schifman RB,Strand CL,Meier FA,et al.Blood culture contamination:a College of American Pathologists Q-Probes study involving 640 institutions and 497134 specimens from adult patients.Arch Pathol Lab Med 1998;122:216-221.Tokars JI.Predictive value of blood cultures positive for coagulase-negative staphylococci:implications for patient care and health care quality assurance.Clin Infect Dis 2004;39:333-341血培养次数333所小型公立医院和私立医院仅仅留取一套血培养的比例12.7%(42.5 3.4%)留取一套血培养比例较低专职的静脉取血人员医院规定至少留取两套血培养医嘱仅留取一套血培养时提醒医生针对留取一套血培养的质控体系Novis DA,Dale JC,Schifman RB,et al.Solitary blood cultures:a College of American Pathologists Q-Probes study of 132,778 blood culture sets in 333 small hospitals.Arch Pathol Lab Med 2001;125:1290-1294.根据阳性培养数鉴别污染菌血培养瓶数培养阳性数临床感染%细菌污染%不明确%1109732129532260337310100032750253310000根据阳性培养数鉴别污染菌一套血培养通常包括需氧和厌氧培养同一套血培养中阳性培养瓶数不应作为鉴别污染菌和致病菌的依据如果某种细菌更容易在需氧条件下生长血培养阳性时间细菌量较大时生长速度更快培养3 5天后阳性者多为污染菌临床试验结果相互矛盾即便致病菌和污染菌培养阳性时间存在差异,临床意义也不明确(数据范围重叠)专家建议:血培养阳性时间不应作为鉴别污染菌和致病菌的标准Weinstein MP.Blood culture contamination:persisting problems and partial progress.J.Clin.Microbiol.2003;41:2275-2278血培养瓶中细菌生长量用于鉴别细菌定植与感染下呼吸道泌尿系静脉导管有关污染菌与菌血症的鉴别缺乏资料 如何鉴别致病菌和污染菌病史体格检查体温外周血白细胞计数和分类病程其他部位培养结果血培养阳性率Weinstein MP,Reller LB,Murphy JR,et al.The clinical significance of positive blood cultures:a comprehensive analysis of 500 episodes of bacteremia and fungemia in adults.I.Laboratory and epidemiologic observations.Rev Infect Dis 1983;5:35-53.致病菌和污染菌的鉴别真正菌血症污染菌分离有毒力的菌株肺炎链球菌克雷白菌属假单胞菌属金黄色葡萄球菌肠杆菌科念珠菌属存在危险因素免疫抑制假体留置导管多部位分离相同菌株培养时间长后续培养没有可重复性分离多种微生物临床情况不提示存在感染分离皮肤定植菌凝固酶阴性葡萄球菌类白喉杆菌杆菌属Shafazand S,Weinacker AB.Blood cultures in the critical care unit.Chest 2002;122:1727-1736外周血培养采集规范通过新的外周静脉留取血标本对血培养瓶进行消毒使用酒精消毒静脉穿刺部位消毒后不要再次触摸穿刺部位Qamruddin A,Khanna N,Orr D.Peripheral blood culture contamination in adults and venepuncture technique:prospective cohort study.J Clin Pathol 2008;61:509-513血培养污染率的影响因素非非污染染污染染污染率染率(%)OR(95%CI)采血者医生486458.41护士266227.60.89(0.51 1.56)未说明/其他580619.5规范依从性依从22762.61不依从4785510.34.35(1.84 12.54)资料不全627679.7Qamruddin A,Khanna N,Orr D.Peripheral blood culture contamination in adults and venepuncture