呼吸道感染的诊治进展.ppt

下呼吸道感染的诊治进展,北京大学第一医院呼吸内科 王广发,Pathogens of LRT Infection,细菌 需氧G+球菌 需氧G-杆菌 厌氧菌病毒真菌支原体立克次体衣原体原虫Pneumocystis carinii,Ten Leading Causes of Death,United States,1997,1 Heart disease 726,974 2 Malignant neoplasms 539,577 3 Cerebrovascular 159,791 4 Bronchitis,Emphysema,Asthma 109,029 5 Unintentional injury and adverse effects 95,644 6 Pneumonia&Influenza 86,449 7 Diabetes 62,636 8 Suicide 30,535 9 Nephritis 25,331 10 Liver disease 25,175,National Center for Health Statistics(NCHS)Vital Statistics System,Gilbert,K and Fine,MJ(1994).Semin Respir Infect 9(3):140-52,Deaths per 100,000,Pneumonia mortality rates per 100,000 patients in the United States from 1900-1990,0,20,40,60,80,100,120,140,160,180,200,1900,1910,1920,1930,1940,1950,1960,1970,1980,1990,Lack of effective therapy;increase in mortality,Community Acquired PneumoniaMortality,Changes of hosts in recent years,人口老龄化低免疫人群的不断增加肾上腺皮质激素、免疫抑制剂降低了宿主免疫功能有创医疗技术广泛应用增加了细菌入侵的途径某些疾病的日益增多糖尿病、AIDS,Changes of Pathogens in Bacterial Pneumonia,病原的多样化革兰氏阴性杆菌性肺炎日益多见原先认为不致病的微生物发现具有致病性新病原的出现-军团菌细菌耐药成为日益普遍的现象(MRSA,ESBL),细菌耐药,甲氧西林耐药的金黄色葡萄球菌（MRSA）甲氧西林耐药的表皮葡萄球菌（MRSE）万古霉素中度敏感的金葡菌（VISA）万古霉素耐药的肠球菌（VRE）青霉素耐药的肺炎链球菌（PRSP）超广谱-内酰胺酶（ESBLs）AmpC碳青霉烯酶,多重耐药菌的分离率 1999年 NNIS调查资料与1994年资料的比较,万古霉素耐药肠球菌：从15%到 26%甲氧西林耐药金黄色葡萄球菌：从38%到55%克雷伯菌对三代头孢菌素的耐药率：从7%到9%铜绿假单胞菌对亚胺培南的耐药率：从12%到19%铜绿假单胞菌对喹诺酮类耐药率：从12%到23%肠杆菌属细菌对三代头孢菌素的耐药率：从34%到 37%,获得性细菌耐药,直接从另一株细菌获得耐药质粒，质粒上携带有耐药基因通过病毒转染从其他细菌获得耐药基因染色体突变从死细菌中获得DNA,万古霉素耐药的肠球菌,万古霉素的用量,万古霉素的用量Kg,耐药率%,产 ESBL菌株分离率的地区差异(1998-2000),0,5,10,15,20,25,30,35,40,45,澳大利亚,日本,台湾,中国,香港,菲律宾,新加坡,大肠杆菌,肺炎克雷伯杆菌,南非,SENTRY,ESBL 阳性百分比,产 ESBL 的地区差异(1998-2000),0,10,20,30,40,50,60,阴沟肠杆菌,粘质沙雷杆菌,澳大利亚,日本,台湾,中国,香港,菲律宾,新加坡,南非,SENTRY,ESBL 阳性百分比,在中国十家医院用E-test法评估六种广谱b-内酰胺药对分离细菌株的体外活性,细菌 数 主要细菌 大肠埃希菌 107肠杆菌属 109 阴沟肠杆菌 克雷伯菌属 120 肺炎克雷伯菌 沙雷菌属 88 黏质沙雷菌 枸橼酸菌属 100 弗劳地枸橼酸菌吲哚阳性变形杆菌属 76 普通变形，摩根绿脓假单胞菌 100 不动杆菌属 99 鲍曼不动杆菌金黄色葡萄球菌(Oxs)101凝固酶阴性葡萄球菌 37 表皮葡萄球菌总计 937,北京协和医院陈民钧教授等,937株细菌对六种药物的总体敏感性排序,药物总体敏感率 亚胺培南96.5马斯平(头孢吡肟)89.1头孢哌酮/舒巴坦85.8头孢他啶75.5头孢曲松66.9哌拉西林57.1,北京协和医院陈民钧教授等,北京协和医院陈民钧教授等,药名耐药中介 MIC50 MIC90头孢吡肟17.011.0364头孢他啶 18.00.01.564头孢曲松50.047.0 32512 亚胺培南21.0 7.0332头孢哌酮/舒巴坦17.0 11.0464哌拉西林 23.0 0.0 8 512,六种抗微生物药对100株铜绿假单胞菌的活性,细菌的进化与耐药,inactivation,impermeability,efflux,A,B,By-pass,Altered target,细菌对抗生素的耐药机制,细胞内药物浓度降低 外排增多 四环素（tetA）氟喹诺酮类（norA）外膜通透性降低 内酰胺类（OmpF;OprD)氟喹诺酮类（OmpF）细胞膜运输能力降低 氨基糖甙类（低能量）药物失活 内酰胺类（内酰胺酶）氨基糖甙类（修饰酶）磷霉素（谷胱甘肽结合）氯霉素（灭活酶）靶位修饰 氟喹诺酮类（旋转酶修饰）利福平（DNA聚合酶结合）内酰胺类（PBP改变）大环内酯类（rRNA甲基化）靶位旁路 糖肽类（vanA、vanB）甲氧苄定（胸腺嘧啶缺陷株）,内酰胺酶的分类（1）,1973年 Richmond&Sykes：酶作用底物、是否被邻氯西林抑制、1976年Matthew&Harris：等电聚焦法、等电点 质粒介导酶:TEM、SHV、HMS、PSE、OXA 染色体介导酶：K1、D31、P991978年Ambler&Scott：氨基酸序列分析 A、B、C、D,内酰胺酶分类（2）,1981年Mitsuhashi&Inoue：酶作用底物 青霉素酶 Pcase(、）头孢菌素酶 Case 头孢呋辛酶 Cxase1989年Bush K：作用底物、是否被CA抑制、酶产生菌及分离率（是否常见）Group 1,2,3,4,内酰胺酶分类（3）Bush,Jacoby&Medeiros(BJM，1995),Routs of Bacteria invading into the lung,口咽部污染分泌物的误吸空气中细菌的吸入细菌血行播散临近组织直接侵入肺脏,Predisposing Factors of lower respiratory tract infection,Pathogenic diagnosis of LRT Infection,痰涂片：简便、快捷 WBC25/LPF，鳞状上皮107/ml致病菌 细菌含量104/ml污染菌,Pathogenic diagnosis of LRT Infection,胸水和血培养：30%菌血症，10%胸水 特异性高，应用范围有限。环甲膜穿刺：分泌物少可注入生理盐水 污染机会少，假阴性率1%，假阳性率21%上气道细菌定植，有一定并发症经皮肺穿刺：污染机会很少，存在并发症，假阴性较多。,Pathogenic diagnosis of LRT Infection,纤维支气管镜：支气管分泌物、肺灌洗、保护性毛刷、保护性肺灌洗,标本30分钟内送检或冷藏保存定量培养PSB103cfu/mlBAL104cfu/mlPSB涂片敏感性20-100%特异性95-100%,PSB的假阴性,在肺炎早期采样取材部位未受累标本处理不当标本于抗生素使用后采取,纤维支气管镜PSB或BAL 指导治疗,Fagon J-Y.Ann Intern Med.2000 Apr 18;132:621-30,(P=0.022),(P 0.001),(P 0.001),气管插管和气管切开者的病原学诊断,Nonbronchoscopic(NB)procedures,e.g.,NB-pBAL or NB-PSB,which utilize blind catheterization of the distal airways,and quantitative culture of endotracheal aspirateEndotracheal aspirate culture appears to be the most practical,Pathogenic diagnosis of LRT Infection,免疫学检查：抗原、抗体 对某些菌有诊断价值 嗜肺军团杆菌 铜绿假单胞菌exotoxin A 特异性LPS抗体 肺炎链球菌分子生物学技术：DNA、PCR 敏感性高、快速，假阳性多开胸或胸腔镜肺活检：慎重考虑,Noninfectious Causes Of Fever And Pulmonary Infiltrates,Chemical aspiration without infection Atelectasis Pulmonary embolism Acute respiratory distress syndrome(ARDS)Pulmonary hemorrhage Long contusion Infiltrative tumor Radiation Pneumonitis Drug reaction Vasculitis Cardiogenic pulmonary edema,下呼吸道感染的治疗,对症及支持治疗,1.休息2.饮食：水电解质平衡、营养3.降温：指征体温超过38.5，物理或药物4.镇咳：严重时用，复方甘草片、咳快好、可待因5.化痰：雾化吸入及化痰6.胸膜痛：止痛7.低氧：吸氧,营养支持,感染时呈负氮平衡消耗增加营养不良时免疫功能减退：淋巴细胞减少 巨噬细胞、中性粒细胞功能受损 免疫球蛋白、补体等物质合成减少 IL-1细胞因子产生减少改善营养状态可改善生存率,改善粘液纤毛的动力学,体位引流改善痰液的粘度：化痰药恢复粘液纤毛的功能 恢复粘液中的盐分含量：痰液的弹性增加吸入移动容易：高张NaCl Na+阻断剂,合理使用抗生素,临床知识药代动力学知识药效和微生物学知识药物不良反应的考虑,抗菌药物的疗效,药物能够抵达感染部位并保持有效的组织浓度对病原菌有灭活或杀死作用不损害宿主的防御机制，最好能够提高防御功能针对性强，对机体的内外环境影响小,抗菌药物的分类（根据药物对细菌的作用）,繁殖期杀菌药-内酰胺类、糖肽类、氟喹诺酮静止期杀菌药氨基甙类和多粘菌素快效抑菌剂 大环内酯、四环素、氯霉素、林可霉素慢效抑菌药磺胺,抗生素对宿主防御功能的影响,对杀菌作用的影响大环内酯类增强头孢菌素类增强青霉素类降低MBC对粘液纤毛功能的影响大环内酯类增强喹诺酮类保护头孢菌素类保护,对氧化爆发的影响大环内酯类抑制呼吸爆发恢复缺损的功能头孢菌素清洁保护上皮细胞对吞噬作用的影响大环内酯类增强头孢菌素类增强青霉素类无影响,联合用药,目的：提高疗效、延缓耐药、降低毒性指征：病因未明的严重感染 单药难以控制的严重感染 免疫功能损害者出现的严重感染 多种病原混合感染 长期用药易产生耐药者 降低毒性较大药物的剂量,协同作用：繁殖期杀菌药+静止期杀菌药杀菌机制不同的增殖期杀菌药内酰胺类+氨基甙内酰胺类+氟喹诺酮内酰胺类+酶抑制剂拮抗作用繁殖期杀菌药+快效抑菌,抗生素应用中的注意事项,根据实验室或临床做出的病原推断选用抗生素最好有药敏结果的指导应了解所选药物的剂量、特点、副作用选用药物、疗程、给药方式应考虑到病情的严重性应注意患者的年龄特点、基础病及用药历史应了解所在地区病原的耐药情况,抗生素治疗失败的原因,药物的吸收、分布不良药物稳定性差感染部位难以进入药物相互作用病原菌对抗生素耐药诊断错误,各类抗菌素在支气管分泌物中的浓度,抗菌素后效应Post Antibiotic Effect,PAE,内酰胺类 对G（+）菌PAE为2-6小时 对G（-）菌很短或无氨基甙类、大环内酯类 对G（+）菌、G（-）菌PAE1-6小时或更长，抗菌素后白细胞增强作用（PALE）,CAP与HAP的区别,CAP：住院48小时以内及住院前出现的肺部炎症HAP：住院48小时以后出现的肺部炎症CAP与HAP的发生率：7-8：1,社会获得性肺炎与医院获得性肺炎的特征,Community-acquired pneumonia(CAP)constitutes a major socioeconomic burden,Epidemiology,IncidenceGeneral population1-11.6 per 1000/year 65 years25-44 per 1000/year 65 years(institutionalized)68-114 per 1000/yearHospitalizationGPs office17-35%MortalityOverall1-3%Hospitalized patients6-24%Requiring ICU22-57%,Niederman,MS,et al(1986).Crit Care Clin.2(3):471-95.Marrie,TJ(1994).Clin Infect Dis 18(4):501-13;Marrie TJ 9(1998).Infect Dis Clin North Am 2(3):723-40,0,5,10,15,20,25,30,S.pneumoniaeC.pneumoniae*ViralM.pneumoniaeLegionella sp.H.influenzaeG-neg enterobacteriaC psittaciCoxiella burnetiiStaph aureusM.catarrhalisOther,Data from 26 prospective studies(5961 adults)from 10 countries.*Data from six studies Woodhead,MA(1998),Community Acquired Pneumonia:Bacteriology in Hospitalized Pts,Common pathogens associated with CAP,*Excluding Pneumocystis.,File TM,Tan JS.Curr Opin Pulm Med.1997;3:89-97.,Streptococcus Pneumoniae,为G（+）球菌，呼吸道寄生有多糖体荚膜（86种亚型）80%为1-8型多见,以1-3型最多,3型毒力最强不产生具有组织破坏作用的毒素不形成空洞,右上叶后段肺炎,Mortality of Pneumococcol Pneumonia in Pre-antibiotic and antibiotic era,S.pneumoniae:prevalence of penicillin-intermediate and-resistant strains,SW USA12%28%,NE USA10%20%,Brazil29%1%,Mexico27%25%,South Africa55%25%,Saudi Arabia44%18%,Hong Kong6%74%,pen-I(penicillin MIC 0.121 g/ml),pen-R(penicillin MIC 2 g/ml),The Alexander Project 1999,SmithKline Beecham data on file,UK6%8%,Belgium6%13%,Spain10%37%,France17%45%,Germany1%4%,Poland5%17%,Switzerland3%11%,Italy7%6%,Portugal 13%10%,Czech Republic1%2%,Slovak Republic15%15%,S.pneumoniae:prevalence of penicillin-intermediate and-resistant strains,pen-I(penicillin MIC 0.121 g/ml),pen-R(penicillin MIC 2 g/ml),The Alexander Project 1999,SmithKline Beecham data on file,Penicillin Non-SusceptibleStreptococcus pneumoniae in the US,%of isolates resistant to penicillin*,Year,*MIC 0.1 to 1.0 g/mL(intermediate)and 2.0 g/mL(high level)penicillin resistance,Appelbaum PC.Clin Infect Dis.1992;15:77-83.Breiman RF,et al.JAMA.1994;271:1831-1835.Doern GV,et al.Antimicrob Agents Chemother.1996;40:1208-1213.Thornsberry C,et al.Diagn Microbiol Infect Dis.1997;29:249-257.Thornsberry C,et al.J Antimicrob Chemother.1999;44:749-759.Thornsberry C,et al.In:Abstracts of the 39th ICAAC,1999,abstract 820.Selman,L.In:Abstracts of the 40th ICAAC,2000,abstract 1789.Selman,L.In:Abstracts of the 40th ICAAC,2000,abstract 1800.Selman,L.In:Abstracts of the 38th IDSA,2000,abstract 200233.Data on file at Ortho-McNeil Pham.,Streptococcus pneumoniae strains recovered from LRT with intermediate and high levels of resistance,Doern GV,Emerging Infectious Diseases 5(6),1999.CDC,多药耐药的肺炎链球菌常见耐药类型,penicillin and TMP/SMX(6.9%)penicillin,macrolide,and chloramphenicol(4.6%)penicillin,macrolide,tetracycline,and TMP/SMX(3.6%)penicillin,macrolide,tetracycline,TMP/SMX,and chloramphenicol(5.4%),Doern GV,Emerging Infectious Diseases 5(6),1999.CDC,The prevalence of macrolide-resistant S.pneumoniae:19921999,Prevalence of macrolide resistance(erythro MIC 1 g/ml;%),Year,Felmingham et al.J Chemother 1999;11:521The Alexander Project 1998/1999.Data available on request from SmithKline BeechamThe Alexander Project 1997(),喹诺酮耐药的肺炎链球菌,喹诺酮耐药逐渐增加(cipro MIC 4 mg/L)0%in 1993,3.7%in 1998,成人耐药的增多与氟喹诺酮类使用量相关 处方量每年0.8%增至5.5%(1988-1997)喹诺酮耐药存在差异:cipro levofloxacin sparfloxacin grepafloxacin trovafloxacin gatifloxacin moxifloxacin gemifloxacin42.9%对青霉素耐药的肺炎链球菌对环丙沙星也耐药,中国5个城市肺炎链球菌对6种抗生素的敏感率（MIC90）,Penicillins Alteration in penicillin-binding proteins(PBPs)Cephalosporins Alterations in PBP2x,PBP1aMacrolides Efflux pump alteration(mef E)Ribosomal methylase(erm AM)Spontaneous mutations Fluoroquinolones Alterations in DNA gyrase(gyr A and gyr B)Alteration in topoisomerase IV(par C and par E),Mechanisms of Antibiotic Resistance in S pneumoniae,肺炎链球菌肺炎的治疗,青霉素G为首选药物青霉素过敏者红霉素、洁霉素、一代头孢菌素对青霉素中中介（MIC0.1-2ug/ml）加大剂量，每日600万单位。对青霉素高度耐药（MIC 2ug/ml）头孢曲松/头孢噻肟、新喹诺酮类、万古霉素，亚胺培南、万古霉素、壁霉素、利福平,G-，含荚膜，营养条件要求高，在巧克力平板生长，根据荚膜分为A、B、C、D、E、F6个血清型，B型致病力最强也最常见感染率20%+发病机理：内毒素-致病过程有重要作用 荚膜其有抗吞噬作用 菌毛粘附定植 IgA蛋白酶支气管肺炎，叶或段的浸润影、空洞、脓胸治疗：AM/CL,TMP/SMX,oral ceph2/3,Cefotaxime,Ceftriaxone、IMP,MER,Ciprofloxacin,流感嗜血杆菌(Haemophilus influenzae),H.influenzae Resistance Trust IV 2000,Abstracts of the 40th ICAAC,2000,abstract 1800.Selman,L.In:Abstracts of the 38th IDSA,2000,abstract 200233Data on file Ortho-McNeil Pharmaceutical,H.influenzaeIncreasing Beta Lactamase Production,1997-1998年亚欧流感嗜血杆菌药敏检测,Atypical Pneumonia,The term atypical pneumonia is commonly used to describe a form of pneumonia in which systemic symptoms are usually more pronounced than respiratory symptoms.,Atypical Respiratory Pathogens,Mycoplasma pneumoniaeLegionella speciesChlamydia pneumoniae Others:respiratory viruses,(influenza A and B,parainfluenza viruses,and respiratory syncytial virus),Chlamydia psittaci(鹦鹉热衣原体),and Coxiella burnetii(伯氏柯克斯体),Mycoplasma pneumoniae,为能在无细胞培养基上生长的最小微生物，无细胞壁，结构简单，营养要求高，生长需要胆固醇对四环素和大环内酯类敏感肺炎支原体能产生过氧化氢及超氧化物溶血素与呼吸道上皮粘附获取外源营养物质可以进入细胞内生长造成上皮细胞及其纤毛的损伤容易与其它病原同时感染宿主,美国每年2百万例肺炎支原体感染其中约5%导致肺炎，相当于 2例/1000人口/年 约20%肺炎支原体的感染没有症状，多数呼吸道症状轻微肺炎支原体可以引起爆发流行（a report by the Centers for Disease Control and Prevention of an outbreak in Colorado）,Mycoplasma pneumoniae,肺炎支原体(Mycoplasma pneumoniae),年轻人及儿童多见，秋季发病多，潜伏期2-3周体温在37.8-39，可伴有头痛、肌痛病理以间质性炎症为主咳痰：少量粘液毯或干咳胸片多表现为斑片状，有时呈网状、云雾状、粟粒状或间质浸润WBC正常或轻度升高冷凝集试验补体依赖性抗体,中耳炎,溶血,神经系统的损害-周围神经炎、脑膜炎、脊髓炎、神经根炎Erythromycin,Tetracycline疗程：7-10d,支原体肺炎,Cold Agglutinin,Blood are collected in Wasserman tube containing NaEDTADefinite floccular agglutination seen with unaided eye(upper panel)Disappears upon warming to 37(bottom panel),Legionella Species,革兰氏阴性杆菌、需氧、不产生芽孢、无荚膜军团菌超过40种 嗜肺军团杆菌（Legionella pneumophila）为主要多数军团菌肺炎（军团病）的病原 L.pneumophila:15个血清型，1型最常见L.pneumophila serogroup 1 可通过尿液检测抗原,Dieterle stain of sputum,Legionella,被吞噬后，在呼吸道巨噬细胞胞体内繁殖释放细胞毒素杀死吞噬细胞释放到细胞外在潮湿环境中繁殖，传播水源、空调器、雾化器污染中央空调系统可引发爆发流行危险因素：高龄、酗酒、吸烟、慢性疾病、器官移植死亡率：免疫功能正常者5-25%,嗜肺军团杆菌(Legionella pneumophila),夏秋发病多，潜伏期2-10天，可伴有消化、神经系统症状、相对缓脉，临床分型流感样型（Pontiac fever）、肺炎型病理：融合的支气管肺炎伴小脓腔形成干咳或血丝痰，WBC1-2万培养方法：BCYE培养基或PCYE培养基抗体：间接荧光抗体大于等于1：128或恢复期血清大于等于1：256，两次抗体滴度增加4倍以上检测痰液、组织和尿中的抗原有重要的诊断价值BAL等的Gimsa染色可以发现细菌并发症：Empyema,Cavitation,Endocarditis,Pericarditis,myositis,ARF红霉素每日2-4g，疗程：3wtrovafloxacin,levofloxacin,moxifloxacin and rifampicin,X线特点：1、病变双侧、多发；2、进展迅速；3、多样性：大片、斑片、斑点结节状、条索、纱网状4、空洞出现快而闭合慢；5、炎症吸收慢,嗜肺军团杆菌(Legionella pneumophila),军团菌肺炎,入院日,入院第3日,入院第5日,Chlamydia pneumoniae,1986年首次发现为呼吸道病原预先存在于细胞内An obligate,intracellular bacterium.双相生长周期在细胞内以网状体形式繁殖释放抗原到上皮表面引起炎症反应并导致纤毛运动障碍C.pneumoniae 缺乏细胞壁为成人及儿童肺炎的常见病原超过50%的成人曾有过感染,Chlamydia pneumoniae,并非终生免疫潜伏期：2-4周 症状通常轻微，也可病程迁延发热及咳嗽为常见的症状，胸部体检可有湿性罗音C.pneumoniae pneumonia:双相病程 咽炎痊愈 1-3周后肺炎病死率:住院患者9.8%Chlamydial complement fixation antibody testing：IgM or IgG elevations that take a minimum of 2-3 weeks to rise after acute infection.,Pneumonia of Mixed Etiology,Atypical pathogens frequently appear as mixed infections1/32/3 are likely coinfections,with S.pneumoniae the presence of at least one other pathogen in:33-64%of M.pneumoniae infections48-74%of C.pneumoniae infections54-63%of Legionella infections,Treatment of Atypical pathogens,Since C.pneumoniae and M.pneumoniae lack a peptidoglycan wall,-lactam antimicrobial agents are ineffective against them.C.pneumoniae and Legionella species can reside in or replicate within cells,necessitating the use of antimicrobials that are active intracellularly.Suitable treatment options are macrolides,fluoroquinolones,or members of the new ketolide class of antimicrobials.Tetracyclines may be used to treat C.pneumoniae or M.pneumoniae,Treatment of CAP,Empiric therapy and pathogen-directed therapyInitiation of prompt antimicrobial therapy is crucial to minimize morbidity,mortality,and health care costs.Antibiotic administration within 8 hours of hospital arrival has been associated with a lower 30-day mortality.Delaying antibiotic administration may increase complications or result in prolonged hospitalizations,Community-Acquired Pneumonia(CAP)Year 2002Antibiotic Selection and Management Update,Evaluation,Risk Stratification,and Current Antimicrobial Treatment Guidelinesfor Hospital-Based Management of CAP:Outcome-Effective Strategies Based onNew NCCLS Breakpoints and Recent Clinical Studies The ASCAP Panel*Consensus Report,2002,Antibiotic Selection for Community-Acquired Pnuemonia,Factors Associated with an Increased Risk for Mortality of CAP,Increasing age(65)AlcoholismChronic lung diseaseImmunodeficiencySpecific laboratory abnormalities(azotemia and hypoxemia),High Risk for Mortality(Radiograph),Bilateral effusionsModerate-size pleural effusionsMulti-lobar involvementBilateral infiltrates,Point Scoring System for Prediction Rule(Pneumonia Severity Index,PSI),*Oxygen saturation 90%is also considered abnormal.,Fine MJ et al.N Engl J Med,Risk classification of patients with CAP,Males ages older than 70 years and females ages older than80 years would be assigned to Class,Patient Management,Outpatient management Class&Brief inpatient observation Class Trditional hospitalization Class&,重症肺炎(The Definition of ATS Guidelines),至少存在下列情况之一：呼吸频率大于 30次/分严重呼吸衰竭(PaO2/FIO2250)需要机械通气者双侧或多个叶的浸润阴影出现休克需要使用升压药者少尿(尿量20ml/hour),98%in sensitivity and 32%in specificity for the need for ICU,CAP year 2002 Antibiotic Selection and Management UpdateTable 1.ASCAP 2002 Guidelines Empiric Antimicrobial Therapy of Choice forOutpatient and In-Hospital Management of Patients with CAP,(To be continued),CAP year 2002 Antibiotic Selection and Management UpdateTable 1.ASCAP 2002 Guidelines Empiric Antimicrobial Therapy of Choice forOutpatient and In-Hospital Management of Patients with CAP,(To be continued),Table 1.ASCAP 2002 Guidelines Empiric Antimicrobial Therapy of Choice forOutpatient and In-Hospital Management of Patients with CAP,Table