基层医院社区获得性肺炎人群的病原学分布及耐药性分析

目的探讨基层医院社区获得性肺炎(CAP)患者的病原学分布情况和常见细菌的耐药性,为基层医院CAP的治疗提供依据。方法选择2010年1月—2013年12月在我院住院治疗的CAP患者360例,对患者的呼吸道分泌物进行病原学培养,分离鉴别细菌,并进行药物敏感性试验;同时检测患者急性期、恢复期肺炎支原体、肺炎衣原体抗体水平。结果 186例(51.67%)CAP患者病原学检测阳性,其中18.82%为混合感染,位于前4位的病原体为肺炎支原体、流感嗜血杆菌、肺炎克雷伯菌、肺炎链球菌及肺炎衣原体。流感嗜血杆菌对氨苄西林的耐药率为42.85%。肺炎克雷伯菌对氨苄西林和部分第三代头孢耐药;青霉素耐药的肺炎链球菌株(PRSP)为29.17%,肺炎链球菌对阿莫西林、头孢曲松等敏感率高。结论流感嗜血杆菌、肺炎克雷伯菌和肺炎链球菌是CAP最常见的致病细菌,但非典型病原体也在CAP中占据重要地位,对各种常用抗菌药物有不同的耐药性。     

社区获得性肺炎病原菌构成及耐药分析

目的研究社区获得性肺炎(CAP)的常见病原菌分布及其耐药性。方法对220例CAP患者同时通过痰培养和血清学检测进行病原菌检测,并用琼脂稀释法检测其最低抑菌浓度(MIC)。结果肺炎链球菌(12.3%)是最常见的病原菌,其后依次为嗜肺军团菌(9.1%)、流感嗜血杆菌(8.6%)、肺炎克雷伯菌(6.8%)和金黄色葡萄球菌(4.1%)。其中肺炎链球菌呈高度多重耐药,对克林霉素、阿奇霉素、四环素等药物的耐药率高达75%以上;流感嗜血杆菌对复方新诺明、氨苄西林、氨苄西林/舒巴坦、头孢呋辛等耐药率较高;肺炎克雷伯菌对左氧氟沙星、莫西沙星、环丙沙星、阿莫西林/克拉维酸、亚胺培南及哌拉西林/他唑巴坦等的敏感性较高。结论肺炎链球菌仍为CAP的重要病原体,多重耐药肺炎链球菌耐药形势严峻。喹诺酮类药物在肺炎链球菌所致CAP治疗中占有重要位置。     

深圳地区社区获得性肺炎病原学分布前瞻性研究

目的：了解深圳地区成人社区获得性肺炎病原的分布情况，为经验治疗提供依据。方法：采用前瞻性方法对40例成人社区获得性肺炎患者留取痰标本进行细菌培养，采用血清学方法检测非典型病原体。结果：40例患者病原学检测阳性32例（80％），其中常见细菌阳性23例（57．5％），病原菌中肺炎链球菌为主；其次为流感嗜血杆菌、副流感嗜血杆菌及铜绿假单胞菌。非典型病原体9例（25％），包括肺炎支原体、细菌合并肺炎支原体感染及肺炎衣原体等。结论：肺炎链球菌是深圳地区社区获得性肺炎的主要致病菌。     

2005-2006年中国社区呼吸道感染细菌耐药性监测

目的调查2005—2006年社区呼吸道感染常见病原菌对头孢克洛及其他5种抗菌药物的耐药性。方法收集2005年10月—2006年8月全国6个地区6所医院社区呼吸道感染患者中分离的流感嗜血杆菌(280株)、肺炎链球菌(105株)、卡他莫拉菌(61株)、β溶血链球菌(30株)和MSSA(30株)共506株。菌株统一由北京医院作复检并用E试验测定头孢克洛等6种抗菌药物的MIC。结果流感嗜血杆菌是社区获得性肺炎(CAP)和慢性支气管炎急性发作(AECB)等感染的最重要的病原菌。分别占CAP56.9%(202株)和AECB64.5%(93株)。药敏结果显示,青霉素敏感的肺炎链球菌(PSSP)为50.5%,青霉素中介肺炎链球菌(PISP)为31.4%,青霉素耐药肺炎链球菌(PRSP)为18.1%。青霉素不敏感率以上海和广州最高(78.6%),其他依次为四川(50%)、天津(46.7%)、浙江(37.5%)和北京(21.1%)。有21.1%的流感嗜血杆菌和93.4%的卡他莫拉菌产生β内酰胺酶。流感嗜血杆菌对头孢克洛、头孢丙烯、阿奇霉素、氨苄西林和莫西沙星分别有98.6%、97.8%、98.6%、85.8%和100%的敏感率。阿奇霉素对肺炎链球菌、β溶血链球菌和MSSA耐药率分别高达94.3%、60%和56.7%。头孢克洛对流感嗜血杆菌和卡他莫拉菌的MIC值低于头孢丙烯1/2。结论与2003年监测结果比较,肺炎链球菌对青霉素的耐药率有较快的增长;流感嗜血杆菌和卡他莫拉菌的产酶率呈上升趋势;肺炎链球菌、β溶血链球菌和MSSA3种革兰阳性球菌对阿奇霉素的耐药率升高;头孢克洛对社区呼吸道感染常见病原菌保持70%~100%的敏感性,提示仍可作为轻中度社区呼吸道感染的选用药物。     

2004-2005年中国社区获得呼吸道感染常见病原菌耐药性研究

目的调查中国6所教学医院2004--2005年分离的社区获得呼吸道感染常见病原菌的耐药性。方法收集2004年7月-2005年3月全国6个地区6所医院社区获得呼吸道感染患者中分离的510株肺炎链球菌、流感嗜血杆菌、卡他莫拉菌、p溶血链球菌及MSSA、非产ESBLs的肺炎克雷伯菌和大肠埃希菌，以琼脂稀释法测定头孢泊肟等9种抗菌药物的MIC。结果肺炎链球菌中，青霉素敏感肺炎链球菌（PSSP）、青霉素中介肺炎链球菌（PISP）、青霉素耐药肺炎链球菌（PRSP）对头孢泊肟的敏感率分别为98．9％、42．2％、6．4％。肺炎链球菌对莫西沙星的敏感率为100％；对米诺环素的敏感率为94．6％；对阿奇霉素的敏感率仅为10．7％；流感嗜血杆菌、MSSA、非产ESBL的肺炎克雷伯菌和大肠埃希菌对头孢泊肟、头孢丙烯、头孢克洛、莫西沙星和米诺环素的敏感率在51．3％～100％。结论呼吸道病原菌特别是肺炎链球菌、流感嗜血杆菌的耐药率与往年监测结果相比较呈增加趋势；头孢泊肟对呼吸道病原菌的抗菌活性优于头孢丙烯和头孢克洛。     

北京部分地区成年患者社区获得性肺炎的病原学及耐药性分析

目的调查研究北京部分地区成年患者社区获得性肺炎的病原学分布及耐药性情况。方法收集389例成年社区获得性肺炎患者的痰液及385例血液标本。痰细菌培养阳性及肺炎支原体和衣原体的血清学试验阳性结果作为感染指征;细菌药敏试验采用纸片扩散法。结果 389例痰液标本中共培养分离出171株细菌,其中最主要的是肺炎链球菌（34/171）,其次是肺炎克雷伯菌（29/171）及金黄色葡萄球菌（22/171）。对385例患者进行非典型病原菌的血清学检测,分别检出104例肺炎支原体和32例肺炎衣原体。分离的肺炎链球菌对红霉素及青霉素的耐药率分别为70.6%和41.2%。结论成年CAP患者中感染率居前3位的细菌为肺炎链球菌、肺炎克雷伯菌及金黄色葡萄球菌。同样,也存在着大量的非典型病原菌感染及混合感染。除了肺炎链球菌对大环内酯类的耐药率较高外,主要致病性细菌的耐药率普遍较低。     

2007年全国CHINET链球菌属分布及耐药性监测

目的 了解全国不同地区12所医院2007年临床分离链球菌属的耐药性.方法 收集12所医院2007年度临床分离链球菌属1 821株,采用纸片扩散法( K-B 法)作药敏试验,并采用CLSI 2007 年的判断标准.结果 1 821株链球菌中肺炎链球菌占38.1 %(694/1 821) ,β溶血性链球菌占44.0 %(802/1 821),草绿色链球菌群17.8%(325/1 821).肺炎链球菌中儿童和成人患者青霉素敏感株(PSSP)的检出率分别为11.5 %和73.7%,儿童分离株中青霉素不敏感株(PISP和PRSP)的检出率分别为69.2 %和19.3 %,成人分离株中PISP和PRSP的检出率分别为13.8%和12.6%.802株β溶血性链球菌中A群占61.2%(491/802),B群23.3%(187/802),C、G、F群共占11.2%(90/802).A及B群对红霉素耐药率高,分别为93.6%和42.9%,其他菌群的耐药率为51.0%～ 64.7% ,5种菌群对青霉素保持较高敏感性.无菌部位草绿色链球菌群对青霉素、红霉素耐药率分别为20.0%和63.3%.未发现对万古霉素、利奈唑胺、替考拉宁耐药的链球菌菌株.结论 肺炎链球菌及β溶血链球菌仍是我国常见病原菌,儿童患者肺炎链球菌对青霉素的耐药率高于成人.我国β溶血链球菌对红霉素的耐药率高且存在群间差异.     

肺炎链球菌对大环内酯类抗生素耐药的研究进展

肺炎链球菌是社区获得性肺炎（CAP）的重要病原菌。大环内酯类抗生素对敏感的革兰阳性菌有效，且对非典型病原体也有较好疗效，被广泛用于治疗CAP和其他呼吸道感染的经验性治疗。肺炎链球菌对大环内酯类抗生素耐药问题也随之成为全球性问题，近10年来逐年加重，以亚洲国家（地区）的肺炎链球菌对大环内酯类抗生素耐药最为严重。本文就肺炎链球菌对大环内酯类抗生素耐药现状、     

85株呼吸道感染肺炎链球菌的耐药性分析

目的了解和分析临床患者呼吸道感染肺炎链球菌的耐药性,为临床治疗肺炎链球菌感染合理应用抗菌药物提供理论依据。方法对浠水县巴驿卫生院2980例呼吸道感染患者的呼吸道分泌物进行细菌培养鉴定及药敏试验,用K-B法做药敏试验,E-test法检测青霉素。结果培养出85例肺炎链球菌,其中青霉素耐药菌株占16.47%,青霉素敏感菌株占62.35%。感染肺炎链球菌的儿童患者中对红霉素和克林霉素的耐药率为96.23%,对磺胺类的耐药率为84.93%;成人患者对红霉素和克林霉素的耐药率为68.75%,对磺胺类的耐药率为65.62%;未见对万古霉素耐药的菌株。儿童患者青霉素耐药率为20.76%,比成年患者耐药率（9.38%）更高。结论临床上感染肺炎链球菌的呼吸道患者对青霉素耐药率较高,尤其儿童患者耐药情况更严重,且存在多重耐药现象,应引起临床医生重视。     

医师问答

1．氟喹诺酮类与第三代头孢菌素联合阿奇霉素治疗需住院的社区获得性肺炎（CAP）患者。孰劣孰优？CAP最常见的病原菌为肺炎链球菌，其次为流感嗜血杆菌、卡他莫拉菌和金葡菌，也可为不典型病原体如军团菌、支原体、衣原体。左氧氟沙星、加替沙星、莫西沙星、吉米沙星等氟喹诺酮类新品种对肺炎链球菌等呼吸道感染常见病原菌的抗菌作用强，同时对肺炎支原体、肺炎衣原体、军团菌等不典型病原体也具有良好抗微生物活性。大环内酯类则因对支原体属、衣原体属及军团菌属等不典型病原体具良好抗微生物活性，     

Sputum specimens can be obtained from patients with community-acquired pneumonia in primary care

OBJECTIVE: To improve the aetiological diagnosis in community-acquired pneumonia (CAP) increased efforts were made to obtain expectorated sputum specimens from patients with CAP. DESIGN: A prospective, clinical study. Patients were encouraged to cough spontaneously and to expectorate a sputum specimen. If unsuccessful, they were asked to inhale nebulized hypertonic saline to induce secretion and cough. SETTING: One primary health care centre in Orebro, Sweden. SUBJECTS: Patients attending the Health Centre with acute symptoms of CAP. MAIN OUTCOME MEASURES: Availability and quality of sputum specimen from patients with CAP in primary care. RESULTS: 177 patients were included, 63% were women and the mean age was 51 years. 28% were smokers and 46% showed infiltrates on chest X-ray. Sputum specimens were obtained from 125 patients. Fifty-nine were expectorated spontaneously and 66 were induced. Ninety-one of the specimens were found to be acceptable, whereas 34 were discarded. Potential pathogens were found in 57% of the 91 specimens. CONCLUSION: Acceptable sputum specimens can be obtained with some effort from approximately half of the patients in primary care. Sputum culture might improve the knowledge of the bacterial aetiology of CAP in selected patients and in epidemiological studies.     

Fluoroquinolones in the management of community‐acquired pneumonia

Aims: Review of the current guidelines for the use of respiratory fluoroquinolones in the management of community‐acquired pneumonia (CAP). Methods: Data were collected from recent clinical trials on fluoroquinolone therapy in patients with CAP and from updated recommendations of antimicrobial therapy in managing CAP, with a focus on current North American guidelines. Results: Randomised clinical trials of respiratory fluoroquinones (moxifloxacin, levofloxacin and gemifloxacin) in the treatment of CAP were identified and analysed. The bacteriology of CAP, and susceptibility rates, resistance rates and pharmacokinetic and pharmacodynamic properties of fluoroquinolones against causative pathogens in CAP, and adverse event profiles of these agents were described. Respiratory fluoroquinones have broad‐spectrum antibacterial activities against common causative pathogens in CAP and provide an important treatment option as monotherapy for outpatients with comorbidities and inpatients who are not admitted to the intensive care unit (ICU), including those with risk factors of drug‐resistant Streptococcus pneumoniae. For treatment of ICU patients with severe CAP, it is recommended that fluoroquinolones be used in combination with a β‐lactam. Recent studies also demonstrated a more rapid resolution of clinical symptoms with the use of highly potent respiratory fluoroquinolones. Discussion: Appropriate use of fluoroquinolone agents may shorten the duration of antimicrobial therapy and the length of hospital stay and contribute to the decreased development of resistance in patients with CAP. Adverse event profiles of these agents should be considered to facilitate the selection of an appropriate fluoroquinolone for appropriate CAP patients. Conclusion: The fluoroquinolone class, specifically those with adequate activity against respiratory pathogens, represents an important and convenient treatment option for patients with CAP.     

Etiology and outcomes of veterans with spinal cord injury and disorders hospitalized with community-acquired pneumonia

OBJECTIVE: To determine whether documentation of a causative organism for community-acquired pneumonia (CAP) is associated with outcomes, including mortality and length of stay (LOS), in hospitalized veterans with spinal cord injuries and disorders (SCI&D). DESIGN: Retrospective cohort study. SETTING: Patients with SCI&D admitted with CAP to any Veterans Affairs medical center between September 1998 and October 2000. PARTICIPANTS: Hospital administrative data on 260 patients with SCI&D and a CAP diagnosis. INTERVENTIONS: Not applicable. MAIN OUTCOMES MEASURES: All-cause, 30-day mortality and hospital LOS. RESULTS: An organism was documented by International Classification of Diseases, 9th Revision , discharge codes in 24% of cases. Streptococcus pneumoniae and Pseudomonas aeruginosa accounted for 32% and 21%, respectively, of the identified bacterial pathogens. The overall mortality rate was 8.5%. No significant association was found between etiologic diagnosis of CAP and 30-day mortality. Lower mortality was associated with treatment at a designated SCI center (relative risk=.35; confidence interval, .12-.99). Pathogen-based CAP diagnosis was significantly associated with longer LOS (adjusted r 2 =.023, P =.024). CONCLUSIONS: There was no association between etiologic diagnosis of CAP and 30-day mortality among people with SCI&D. Documentation of CAP etiology was associated with the variance in LOS. Pneumococcal vaccination and antibiotic therapy with antipseudomonal activity may be particularly prudent in these patients given the high frequency of these pathogens among SCI&D patients with CAP.     

A prospective comparison of nursing- and healthcare-associated pneumonia (NHCAP) with community-acquired pneumonia (CAP)

Nursing- and healthcare-associated pneumonia (NHCAP) has been proposed by the Japanese Respiratory Society as a new category of pneumonia considering the characteristics of the Japanese medical care environment. It is necessary to ascertain the epidemiology and clinical outcomes of NHCAP. A prospective study was conducted of patients with pneumonia who were hospitalized at our hospital from August 2011 to July 2012. We compared 192 cases of NHCAP with 114 cases of community-acquired pneumonia (CAP). Compared with CAP, NHCAP had a higher disease severity, higher 30-day mortality rate (10.9 vs. 3.5 %, P = 0.022), and longer length of hospital stay (median, 12 vs. 8 days, P < 0.001). Streptococcus pneumoniae was the most frequent causative pathogen in both NHCAP and CAP (33.9 vs. 34.8 %, P = 0.896). The incidence of atypical pathogens in NHCAP was low (1.7 %). Multidrug-resistant (MDR) pathogens were isolated more frequently in NHCAP than in CAP, but there was no significant difference (11.0 vs. 4.5 %, P = 0.135). Among 192 NHCAP patients, 122 (63.5 %) were aspiration pneumonia. Aspiration pneumonia was associated with poor outcomes and was considered a major characteristic of NHCAP. Our study suggested that many patients with NHCAP do not need broad-spectrum antibiotic therapy targeting MDR pathogens. Excess mortality in NHCAP patients is the result of patient backgrounds or disease severity rather than the presence of MDR pathogens.     

白细胞不增高的社区获得性肺炎病原分析及临床特征

目的：分析外周血白细胞正常或降低的社区获得性肺炎(CAP)病因及临床特点。方法：采用标准的培养技术及血清学方法检测89例白细胞不高的CAP患者呼吸道及血液标本的常见病原体，并分析其临床资料。结果：89例中军团菌属最多，占28．1％(25／89)，病毒占18．0％(16／89)，其中主要为流感病毒A(6例)、流感病毒B(7例)，肺炎支原体占18．0％(16／89)，细菌占4．3％(3／89)，肺炎衣原体最少(1／89)，有38．2％(34／89)的患者不能明确病原体，多种病原体混合感染占25．8％。病毒性肺炎、军团菌肺炎及肺炎支原体肺炎的临床症状、体征、外周血白细胞、胸部影像均无特异性，其鉴别须靠病原微生物检查。结论:外周血白细胞正常或降低的CAP病因主要为非典型病原体和病毒，对这类CAP的经验治疗应以大环内酯类抗生素或抗病毒药物为主。     

老年与非老年社区获得性肺炎患者的临床特点比较

目的 探讨老年与非老年社区获得性肺炎（CAP）患者的临床特点。 方法 检索我院2014年4月~2017年4月呼吸内科电子病历系统,纳入CAP患者292例,比较其一般项目、住院时间、入院时患者首发症状、痰培养结果、抗生素应用情况、临床及实验室资料。 结果 292例CAP患者,年龄14～89岁（49.10±19.4岁）,住院时间9.11±3.23 d,细菌培养率为11.64%,老年组与非老年组患者的基础合并症、痰培养、中性粒细胞数、降钙素原、红细胞沉降率差异有统计学意义（P<0.05）,两组患者的住院时间、C反应蛋白、入院症状差异无统计学意义（P>0.05）。老年组患者与非老年组患者的B类酰胺类、喹诺酮类、大环内酯类使用差异无统计学意义,林可酰胺类使用差异有统计学意义（P<0.05）。 结论 老年组CAP患者常合并各种基础疾病,老年组患者的降钙素原敏感度、痰培养阳性率高于非老年组患者,病原体检出阳性率低。       

Selective use of blood cultures in emergency department pneumonia patients

Our objectives were to identify factors associated with positive blood cultures and to evaluate blood culture use in the management of hospitalized pneumonia patients to limit their use. A retrospective chart review was conducted at a community teaching hospital. Emergency Department patients with an admission diagnosis of pneumonia during calendar years 2001-2002 were included. Patients younger than age 18 years and those with a non-pneumonia discharge diagnosis were excluded. Of 684 eligible patients, 23 (3.4%) had true positive blood cultures. All organisms were sensitive to empiric antibiotics. Three risk factors were associated with positive blood cultures: oxygen saturation < 90%, serum sodium < 130 and respiratory rate > 30 breaths/min. No patient had antibiotic coverage broadened based on blood culture results. Positive blood culture rates were low and did not affect the clinical management of pneumonia patients. We recommend eliminating blood cultures in community-acquired pneumonia (CAP) patients, but obtaining blood cultures in patients at risk for multi-drug resistant pathogens, such as health-care-associated pneumonia (HCAP) patients.     

Health care-associated pneumonia and community-acquired pneumonia: a single-center experience

Pneumonia occurring outside of the hospital setting has traditionally been categorized as community-acquired pneumonia (CAP). However, when pneumonia is associated with health care risk factors (prior hospitalization, dialysis, residing in a nursing home, immunocompromised state), it is now more appropriately classified as a health care-associated pneumonia (HCAP). The relative incidences of CAP and HCAP among patients requiring hospital admission is not well described. The objective of this retrospective cohort study, involving 639 patients with culture-positive CAP and HCAP admitted between 1 January 2003 and 31 December 2005, was to characterize the incidences, microbiology, and treatment patterns for CAP and HCAP among patients requiring hospital admission. HCAP was more common than CAP (67.4% versus 32.6%). The most common pathogens identified overall included methicillin-resistant Staphylococcus aureus (24.6%), Streptococcus pneumoniae (20.3%), Pseudomonas aeruginosa (18.8%), methicillin-sensitive Staphylococcus aureus (13.8%), and Haemophilus influenzae (8.5%). The hospital mortality rate was statistically greater among patients with HCAP than among those with CAP (24.6% versus 9.1%; P < 0.001). Administration of inappropriate initial antimicrobial treatment was statistically more common among HCAP patients (28.3% versus 13.0%; P < 0.001) and was identified as an independent risk factor for hospital mortality. Our study found that the incidence of HCAP was greater than that of CAP among patients with culture-positive pneumonia requiring hospitalization at Barnes-Jewish Hospital. Patients with HCAP were more likely to initially receive inappropriate antimicrobial treatment and had a greater risk of hospital mortality. Health care providers should differentiate patients with HCAP from those with CAP in order to provide more appropriate initial antimicrobial therapy.     

The role of viruses in the aetiology of community-acquired pneumonia in adults

BACKGROUND: The role of viruses in community-acquired pneumonia may have been previously underestimated. We aimed to study the incidence and clinical characteristics of community-acquired pneumonia (CAP) due to respiratory viruses in adults adding PCR to routine conventional laboratory tests. METHODS: Consecutive adult patients diagnosed of CAP from January 2003 to March 2004 were included. Conventional tests including cultures of blood, sputum, urine antigen detection of Streptococcus pneumoniae and Legionella pneumophila, and paired serologies were routinely performed. Nasopharyngeal swabs were processed for study of respiratory viruses through antigen detection by indirect immunofluorescence assay, isolation of viruses in cell culture and detection of nucleic acids by two independent multiplex RT-PCR assays. According to the aetiology, patients were categorized in 4 groups: group 1, only virus detected; group 2, only bacteria detected; group 3, viral and bacterial; and group 4, unkown aetiology. RESULTS: Of 340 patients diagnosed with CAP, 198 had nasopharyngeal swabs available and were included in this study. Aetiology was established in 112 (57%) patients: group 1, n=26 (13%); group 2, n=66 (33%); group 3, n=20 (10%). The most common aetiological agent was S. neumoniae (58 patients, 29%), followed by respiratory viruses (46 patients, 23%). Forty-eight respiratory viruses were identified: influenza virus A (n=16), respiratory syncytial virus A (n=5), adenovirus (n=8), parainfluenza viruses (n=5), enteroviruses (n=1), rhinoviruses (n=8) and coronavirus (n=5). There were two patients coinfected by two respiratory viruses. Serology detected 6 viruses, immunofluorescence 8, viral culture 12, and PCR 45. For the viruses that could be diagnosed with conventional methods, the sensitivity and specificity of RT-PCR was 85% and 92%, respectively. The only clinical characteristic that significantly distinguished viral from bacterial aetiology was a lower number of leukocytes (P=0.004). CONCLUSION: PCR revealed that viruses represent a common aetiology of CAP. There is an urgent need to reconsider routine laboratory tests for an adequate diagnosis of respiratory viruses, as clinical characteristics are unable to reliably distinguish viral from bacterial aetiology.