The role of atypical pathogens in community-acquired pneumonia

The term atypical pneumonia was first used in 1938, and by the 1970s it was widely used to refer to pneumonia due to Mycoplasma pneumoniae, Legionella pneumophila (or other Legionella species), and Chlamydophila pneumoniae. However, in the purest sense all pneumonias other than the classic bacterial pneumonias are atypical. Currently many favor abolition of the term atypical pneumonia.This review categorizes atypical pneumonia pathogens as conventional ones; viral agents and emerging atypical pneumonia pathogens. We emphasize viral pneumonia because with the increasing availability of multiplex polymerase chain reaction we can identify the agent(s) responsible for viral pneumonia. By using a sensitive assay for procalcitonin one can distinguish between viral and bacterial pneumonia. This allows pneumonia to be categorized as bacterial or viral at the time of admission to hospital or at discharge from the emergency department and soon thereafter further classified as to the etiology, which should be stated as definite or probable.     

Microbiologic diagnosis of community-acquired pneumonia in adults

Microbiological analysis allows us to identify the etiology of pneumonia and its in vitro susceptibility pattern. Antibiotic treatment directed against a known pathogen enables us to narrow antibacterial spectrum of action, and to reduce costs, drug adverse effects risk and antibiotic resistance. However it is unnecessary to perform extended microbiological studies in all patients with community acquired pneumonia (CAP). Etiological studies must be based in pneumonia severity, epidemiological risk factors and clinical response to empirical treatment. Routine microbiological analysis for ambulatory patients is not recommended. In patients with persistent cough and worsening in their general conditions, a sputum sample must be obtained to perform an acid-fast smear and Mycobacterium culture. The risk of complications and death of patients hospitalized with CAP justifies basic microbiological exploration (sputum Gram staining and culture, blood cultures, pleural fluid culture) intending to obtain a more accurate etiology of pulmonary infection and to guide specific antibiotic treatment. Paired serum samples obtained to document atypical pathogen infections (Mycoplasma pneumoniae, Chlamydia pneumoniae) and urine sample to detect Legionella pneumophila antigenuria are recommended in all CAP severely ill patients that are admitted to ICU, in those not responding to betalactamic drug treatment and in selected patients with specific epidemiological risks. A microbiological study would be useful in management of patients with severe CAP pneumonia outbreaks with clinical-epidemiological particular characteristics, and in-patients with empirical antimicrobial treatment failure.     

Inflammatory biomarkers for the diagnosis, monitoring and follow-up of community-acquired pneumonia: clinical evidence and perspectives

Community-acquired pneumonia (CAP) is defined as an infection of the alveolar or gas-exchanging portions of the lungs occurring outside the hospital, with clinical symptoms accompanied by the presence of an infiltrate in the chest radiograph. Due to the high prevalence and the large demand of healthcare resources, an accurate clinical and therapeutic decision making is crucial in patients with CAP. As such, there is increasing interest on the use of traditional and innovative biomarkers such as procalcitonin (PCT) and C-reactive protein (CRP). At variance with other traditional inflammatory and innovative biomarkers, PCT might help limiting unnecessary antibiotic use, reduce bacterial resistance and decrease medical costs and drug-related adverse events. PCT however carries some additional advantages over CRP, such as the greater specificity for infections and a more narrow range of normal concentrations.     

The role of new therapies for severe community-acquired pneumonia

PURPOSE OF REVIEW: Community-acquired pneumonia (CAP) is associated with significant morbidity and mortality and is the most common cause of death from infectious diseases. CAP patients requiring intensive care unit (ICU) admission carry the highest mortality rates. This paper aims to review the current literature regarding epidemiology, risk factors, severity criteria and reasons for admitting the hospitalized patient to the ICU, and the empiric and specific antibiotic therapeutic regimens employed. RECENT FINDINGS: Multiple sets of clinical practice guidelines have been published in the past few years addressing the treatment of CAP. The guidelines all agree that CAP patients admitted to the hospital represent a major concern, and appropriate empiric therapy should be instituted to improve clinical outcomes. SUMMARY: The cost, morbidity and mortality of CAP patients requiring ICU admission remain unacceptably high. These are heterogeneous groups of patients, so it is important to use risk-stratification based on clinical parameters and prediction tools. Appropriate antibiotic therapy is an important component in the management of both groups of patients. In particular, it is essential to administer an appropriate antimicrobial agent from the initiation of therapy, so that the risks of treatment failure and the morbidity of CAP may be minimized.     

社区获得性肺炎诊疗新进展

近年来,社区获得性肺炎流行调查显示其患病率及病死率逐渐增高,重症患者增多。而在临床诊疗上,存在病原学诊断不清、对血清学检测意义认识不足、严重程度评估欠准确、抗生素不合理应用等现象。本文参阅了大量近年来国内外发表的有关社区获得性肺炎的最新文献,在血清学、病原学、抗生素合理使用、是否应用激素、辅助治疗及诊治前沿新进展等方面进行综述。     

Clinical and radiological diagnosis of community-acquired pneumonia in adults

Community acquired pneumonia in adults is an acute disease characterized by worsening in general conditions, fever, chills, cough, mucopurulent sputum and dyspnea; associated with tachycardia, tachypnea, fever and focal signs in pulmonary examination. The probability of pneumonia in a patient with acute respiratory symptoms depends on the disease prevalence in the environment where it is acquired and on clinical features. It is estimated that pneumonia prevalence is 3-5% in patients with respiratory disease seen in outpatient facilities. Clinical diagnosis of pneumonia without radiological confirmation lacks specificity because clinical presentation (history and physical examination) does not allow to differentiate pneumonia from other acute respiratory diseases (upper respiratory infections, bronchitis, influenza). Diagnosis must be based in clinical-radiological findings: clinical history and physical examination suggest the presence of pulmonary infection but accurate diagnosis is established when chest X ray confirms the existence of pulmonary infiltrates. Clinical findings and chest X ray do not permit to predict with certainty the etiology of pulmonary infection. Radiology is useful to confirm clinical suspicion, it establishes pneumonia location, its extension and severity; furthermore, it allows differentiation between pneumonia and other diseases, to detect possible complications, and may be useful in follow up of high risk patients. The resolution of radiological infiltrates often ensues several weeks or months after clinical recovery, especially in the elderly and in multilobar pneumonia cared for in intensive care units.     

社区获得性肺炎的诊治进展

社区获得性肺炎的诊断和治疗方法近年来在不断完善,但是社区获得性肺炎的正确诊断及合理化治疗仍然是临床医师需要面临的问题.本文对社区获得性肺炎的诊治进展情况进行介绍.     

Severe community-acquired pneumonia. Risk factors and follow-up epidemiology.

The aim of the study was to determine risk factors for severe community-acquired pneumonia (CAP) as well as to compare microbial patterns of severe CAP to a previous study from our respiratory intensive care unit (ICU) originating from 1984 to 1987. Patients admitted to the ICU according to clinical judgment were defined as having severe CAP. For the study of risk factors, a hospital-based case-control design was used, matching each patient with severe CAP to a patient hospitalized with CAP but not requiring ICU admission. Microbial investigation included noninvasive and invasive techniques. Overall, 89 patients with severe CAP were successfully matched to a control patient. The presence of an alcohol ingestion of >/= 80 g/d (odds ratio [OR] 3.9, 95% confidence interval [CI] 1.4 to 10.6, p = 0.008) was found to be an independent risk factor for severe CAP and prior ambulatory antimicrobial treatment (OR 0.37, 95% CI 0.17 to 0.79, p = 0.009) to be protective. Streptococcus pneumoniae (24%) continued to be the most frequent pathogen; however, 48% of strains were drug-resistant. "Atypical" bacterial pathogens were significantly more common (17% versus 6%, p = 0.006) and Legionella spp. less common (2% versus 14%, p = 0.004) than in our previous study, whereas gram-negative enteric bacilli (GNEB) and Pseudomonas aeruginosa continued to represent important pathogens (6% and 5%, respectively). Our findings provide additional evidence for the importance of the initiation of early empiric antimicrobial treatment for a favorable outcome of CAP. Variations of microbial patterns are only in part due to different epidemiological settings. Therefore, initial empiric antimicrobial treatment will also have to take into account local trends of changing microbial patterns.     

生物标志物在社区获得性肺炎诊治中的应用进展

社区获得性肺炎（community acquired pneumonia,CAP）是威胁人类健康尤其是老年人群的常见疾病之一.随着耐药菌株不断涌现,临床抗感染的治疗效果不尽人意,CAP的病死率居高不下,是感染性疾病死亡的首要原因.由于CAP在世界范围内的高发病率和病死率给社会带来巨大的经济负担,世界各国相关权威机构为了提高CAP的诊治水平,改善患者的预后,节约有限的医疗卫生资源,纷纷出台CAP的诊治指南并不断修订.在CAP整个治疗过程中,病情评估、预后预测、抗生素的使用是最重要的几个环节,关系到CAP的治疗成败,而越来越多的生物标记物被用于这几个环节中,现对此领域最新进展做一综述.     

降钙素原、C 反应蛋白在诊断社区获得性肺炎中的价值评价

目的探讨降钙素原（PCT）、白细胞介素（IL）-6、C 反应蛋白（CRP）、外周血白细胞（WBC）在诊断社区获得性肺炎（CAP）中的诊断价值。方法共纳入因急性发热入院患者共107例,CAP 组59例、急性上呼吸道感染（简称上感）组48例。比较 PCT、IL-6、CRP、WBC 在两组间的差异。根据受试者工作特征曲线（ROC）下面积（AUC）,评价4个参数对诊断 CAP 的价值,并得出最佳的诊断截点值。结果PCT、CRP、WBC 在 CAP 组较上感组明显增高,差异均有统计学意义（P＜0．05）。PCT、IL-6、CRP、WBC 预测 CAP 的 AUC 分别为0．89、0．79、0．91、0．77。PCT、CRP 曲线下面积均高于 IL-6、WBC,差异有统计学意义（P ＜0．05）,表明 PCT 和 CRP 对诊断 CAP 可能具有较高的准确性。PCT ＝0．3 ng／ml 时预测 CAP 的敏感度为77．8％,特异度为85．4％,推荐为最佳截点值。CRP ＝120 mg／L 时,其预测 CAP 的敏感度为84．4％,特异度为93．3％,推荐为最佳截点值。结论PCT、CRP 可能是诊断 CAP 有效的生物标志物,可作为传统诊断模式的有效补充。     

甘露聚糖结合凝集素与社区获得性肺炎研究进展

社区获得性肺炎(CAP)是发病率及病死率很高的疾病,应加强研究CAP的危险因素,寻找干预措施降低CAP的病死率.甘露聚糖结合凝集素(MBL)是一种存在于血清中的C型凝集素,通过结合病原生物表面的甘露聚糖等糖基受体而直接介导调理吞噬作用和(或)通过MBL途径激活补体,在机体的固有性免疫防御中发挥重要作用.MBL基因突变可致血清MBL水平低下和功能缺损,使个体易患某些感染性疾病.本文简述了MBL结构和功能,并综述国内外有关MBL不足或缺失对CAP易感性及严重程度的影响及MBL在医学领域的应用.     

Utility of radiography and clinical features in the diagnosis of community-acquired pneumonia

This article reviews the approach to the differential diagnosis of community-acquired pneumonia using clinical clues and radiography. Evidence is reviewed that indicates that the etiology of such pneumonias is changing. The basic clinical patterns, including bacterial, nonbacterial, and mixed presentations are discussed, as well as how aspiration, diabetes, and alcoholism affect the differential diagnosis.     

莫西沙星与左氧氟沙星治疗社区获得性肺炎的临床研究

目的探讨莫西沙星和左氧氟沙星治疗社区获得性肺炎的疗效。方法选择社区获得性肺炎患者120例,随机分成莫西沙星组60例和左氧氟沙星组60例,分别给予治疗7 d,运用药物经济学的成本-效果分析方法进行评价。结果莫西沙星组和左氧氟沙星组治疗有效率分别为98.33%和71.67%,细菌清除率分别为91.67和65.57%,不良反应发生率分别为8.33%和13.33%,成本-效果比分别为21.87%和10.26%。结论莫西沙星组的治疗有效率和细菌清除率明显优于左氧氟沙星组（P〈0.01）,莫西沙星治疗社区获得性肺炎在临床治疗中是优选方案。     

社区获得性肺炎非典型病原体的诊断方法进展

社区获得性肺炎（community-acquired pneumonia,CAP）是指在医院外罹患的肺实质感染性（含肺泡壁,即广义上的肺间质）炎症,包括具有明确潜伏期的病原体感染,在入院后潜伏期内发病的肺炎.CAP严重威胁人类健康,在世界不同的国家和地区有较高的发病率.引起CAP的主要病原体有细菌、病毒以及非典型病原体等,其中仍以肺炎链球菌和流感嗜血杆菌为代表的细菌较常见.     

糖皮质激素在重症肺炎中的辅助治疗作用

重症社区获得性肺炎(severe community-acquired pneumonia,SCAP)是一种常见疾病,尽管目前临床诊断、治疗等已取得了很大进步,但其住院率及病死率仍居高不下.本综述简述了SCAP的炎症反应机制、糖皮质激素在炎症反应中的作用及其在重症肺炎治疗中的进展,并就治疗方面一直存在的争议进行了探讨,提出了糖皮质激素在重症肺炎综合治疗中的作用已日渐突出,且短疗程、小剂量应用糖皮质激素是有利的.     

Lung ultrasound in the diagnosis of stroke-associated pneumonia

Pneumonia is a common complication in stroke patients; it is associated with an adverse outcome, prolonged hospital stay and increased health costs. The aim of this study was to assess the ability of lung ultrasound to rule in or rule out pneumonia in patients with stroke. Patients with ischemic or hemorrhagic stroke were included in the study if they had a clinical suspicion of pneumonia. Lung ultrasound imaging and chest X-ray studies were performed within 24 h from the onset of symptoms of pneumonia; the sonographer and radiologists were unaware of the chest X-ray study and ultrasound imaging results, respectively. In case of discordant results, lung computed tomography (CT) was performed if a definitive diagnosis was required to optimize clinical management. Seventy patients were included in the study. Among 24 patients with unilaterally positive chest X-ray studies, the ultrasound imaging was unilaterally positive in 19 cases (79.2 %), bilaterally positive in 3 cases (12.5 %) and negative in 2 cases (8.3 %). Among 44 patients with negative chest X-ray studies, ultrasound imaging was unilaterally positive in 17 cases (38.6 %), bilaterally positive in 2 cases (4.6 %), negative in 19 cases (43.2 %) and non-conclusive in 6 cases (13.6 %). A lung CT scan was performed in 9 of the 21 discordant cases, and it always confirmed the ultrasound imaging results. Ultrasound imaging and chest X-ray studies were concordant in 42 out of 63 cases, 66.7 % (Pearson χ² = 11.97, p = 0.001). In conclusions, this study shows the utility of LUS imaging to rule in or rule out pneumonia in patients with stroke. We believe that lung ultrasound imaging can help clinicians in the diagnosis of stroke-associated pneumonia.     

Surgical drainage of lung abscess complicating acute community-acquired pneumonia

Two cases of severe community-acquired pneumonia requiring IPPV and complicated by the development of lung abscess were successfully treated with early surgical drainage. This procedure may be a life-saving measure in certain instances.     

儿童社区获得性肺炎护理吸痰方法对病原学诊断的影响

通过痰细菌培养来协助儿童社区获得性肺炎的病原学诊断有一定的临床意义,适当的护理吸痰方法、技巧和流程有助于提高肺炎患儿痰细菌培养的可靠性.该文就儿科常用吸痰方法和技巧,及其对肺炎患儿痰细菌培养结果的影响作一综述.