鲍曼不动杆菌呼吸机相关性肺炎的危险因素分析

目的 研究重症监护病房鲍曼不动杆菌(Acinetobacter baumannii,Ab)呼吸机相关性肺炎(VAP)的危险因素,为临床防治VAP提供依据.方法 采用回顾性方法,调查2008年1月至2011年12月重症监护病房鲍曼不动杆菌感染VAP患者的危险因素.采用x2检验进行单因素分析.结果 共调查389例患者,VAP发病率为28.8％(112例),病死率为32.1％(36例).VAP的发生与APACHEⅡ评分、机械通气时间、机械通气方式、抗生素联合使用、昏迷、留置胃管、年龄、以及使用糖皮质激素有关.结论 VAP的发生与多种临床因素相关,加强危险因素监测,严格落实无菌操作制度,集束化管理有助于减少VAP的发生.     

Oral health care and aspiration pneumonia in frail older people: a systematic literature review

Objective: To systematically review the literature on oral health care interventions in frail older people and the effect on the incidence of aspiration pneumonia. Background: Oral health care seems to play an important role in the prevention of aspiration pneumonia in frail older people. Methods: Pubmed, Web of Science, Cochrane Library, EMBASE and CINAHL were searched for eligible intervention studies. Only publications with regard to hospitalized or institutionalized older people, who were not dependent on mechanical ventilation were eligible. Two authors independently assessed the publications for their methodological quality. Results: Five publications were included and reviewed. Two studies showed that improvement of oral health care diminished the risk of developing aspiration pneumonia and the risk of dying from aspiration pneumonia directly. The three studies remaining showed that adequate oral health care decreased the amount of potential respiratory pathogens and suggested a reduction in the risk of aspiration pneumonia by improving the swallowing reflex and cough reflex sensitivity. Conclusions: According to the results of the current systematic literature review oral health care, consisting of tooth brushing after each meal, cleaning dentures once a day, and professional oral health care once a week, seems the best intervention to reduce the incidence of aspiration pneumonia.     

NK1.1(+) cells regulate neutrophil migration in mice with Acinetobacter baumannii pneumonia

Acinetobacter baumannii is a major cause of both community-associated and nosocomial infections worldwide. These infections are difficult to treat because the bacterium rapidly develops resistance to multiple antibiotics. However, little is known about the nature of the innate cellular response to A. baumannii infection. In the present study, we identified the cells infiltrating the lungs of mice with Acinetobacter pneumonia and analyzed their response to infection. Normal mice eradicated the A. baumannii infection within 3 days of inoculation. Neutrophils were rapidly recruited to the lungs, followed by macrophages and NK1.1(+) cells. Neutrophil-depleted mice showed acute and severe symptoms, and all of the mice died within 3 days of inoculation. The majority of macrophage-depleted mice responded in a similar manner to the control mice. These results indicate that neutrophils are essential for the elimination of A. baumannii. Half of NK1.1(+) cell-depleted mice died within 1 day of inoculation and the number of infiltrating neutrophils was lower than that in control mice up until 3 days post-inoculation. Moreover, the expression levels of keratinocyte chemoattractant protein (KC) decreased in NK1.1(+) cell-depleted mice. These results indicate that NK1.1(+) cells recruit neutrophils during the early phase of Acinetobacter infection by increasing KC expression.     

鲍曼不动杆菌临床分布、耐药性分析和肺部感染病例的预后研究

目的了解浙江大学医学院附属第一医院临床分离鲍曼不动杆菌的分布情况、耐药状况以及肺部感染病例的临床预后,为临床鲍曼不动杆菌感染的治疗提供参考。方法分析该院2013年1月至2013年6月培养到的非重复鲍曼不动杆菌420株的临床分布和耐药性,回顾性分析鲍曼不动杆菌肺炎并接受头孢哌酮/舒巴坦治疗患者的临床资料。结果 420株鲍曼不动杆菌来源以重症监护室（ICU）为主,占45.96%。其次为外科（神经外科、肝胆外科）,占36.19%。标本构成中以呼吸道标本最高（66.90%）,其次为血培养（8.81%）。共有79例（18.8%）患者≥2个部位分离到鲍曼不动杆菌,其中62例（78.5%）呼吸道是首发的分离部位、之后出现第二个部位培养阳性。体外药敏显示,鲍曼不动杆菌对阿米卡星、替加环素、左氧氟沙星、头孢哌酮/舒巴坦、氨苄西林/舒巴坦、亚胺培南和美罗培南的耐药率分别为5.2%、15.9%、35.6%、64.2%、71.1%、79.1%和88.9%。选取其中诊断为肺炎患者72例。72例患者粗死亡14例（19.4%）。患者病情好转组治疗初C反应蛋白平均水平为69.5 mg/L、死亡组为137.6 mg/L,经比较差异有统计学意义（P〈0.05）;患者病情好转组治疗初APACHE II为16.4、死亡组为19.7,经比较两组差异有统计学意义（P〈0.05）。结论入住重症监护室、外科手术后患者是鲍曼不动杆菌分离的主要人群,18.8%的患者在多个部位培养到鲍曼不动杆菌,鲍曼不动杆菌耐药率高,抗菌药物选择困难。治疗初期C反应蛋白和APACHE II水平对预后有参考价值。     

Cardiac complications in patients with community-acquired pneumonia: a systematic review and meta-analysis of observational studies

Background

Community-acquired pneumonia (CAP) is a leading cause of morbidity and mortality. CAP can trigger acute cardiac events. We sought to determine the incidence of major cardiac complications in CAP patients to characterize the magnitude of this problem.

Methods and Findings

Two investigators searched MEDLINE, Scopus, and EMBASE for observational studies of immunocompetent adults with clinical and radiological evidence of CAP that reported any of the following: overall cardiac complications, incident heart failure, acute coronary syndromes (ACS), or incident cardiac arrhythmias occurring within 30 days of CAP diagnosis. At a minimum, studies had to establish enrolment procedures and inclusion and exclusion criteria, enrol their patients sequentially, and report the incidence of cardiac complications as a function of their entire cohorts. Studies with focus on nosocomial or health care–associated pneumonia were not included. Review of 2,176 citations yielded 25 articles that met eligibility and minimum quality criteria. Seventeen articles (68%) reported cohorts of CAP inpatients. In this group, the pooled incidence rates for overall cardiac complications (six cohorts, 2,119 patients), incident heart failure (eights cohorts, 4,215 patients), acute coronary syndromes (six cohorts, 2,657 patients), and incident cardiac arrhythmias (six cohorts, 2,596 patients), were 17.7% (confidence interval [CI] 13.9–22.2), 14.1% (9.3–20.6), 5.3% (3.2–8.6), and 4.7% (2.4–8.9), respectively. One article reported cardiac complications in CAP outpatients, four in low-risk (not severely ill) inpatients, and three in high-risk inpatients. The incidences for all outcomes except overall cardiac complications were lower in the two former groups and higher in the latter. One additional study reported on CAP outpatients and low-risk inpatients without discriminating between these groups. Twelve studies (48%) asserted the evaluation of cardiac complications in their methods but only six (24%) provided a definition for them. Only three studies, all examining ACS, carried out risk factor analysis for these events. No study analyzed the association between cardiac complications and other medical complications or their impact on other CAP outcomes.

Conclusions

Major cardiac complications occur in a substantial proportion of patients with CAP. Physicians and patients need to appreciate the significance of this association for timely recognition and management of these events. Strategies aimed at preventing pneumonia (i.e., influenza and pneumococcal vaccination) in high-risk populations need to be optimized. Further research is needed to understand the mechanisms underlying this association, measure the impact of cardiac complications on other CAP outcomes, identify those patients with CAP at high risk of developing cardiac complications, and design strategies to prevent their occurrence in this population. Please see later in the article for the Editors'' Summary     

重症监护病房呼吸机相关性肺炎中鲍曼不动杆菌耐药性的动态分析

目的探讨重症监护病房呼吸机相关性肺炎(VAP)中鲍曼不动杆菌(Acinetobacter baumannii,Ab)的分布特点和耐药性,为临床防治鲍曼不动杆菌感染提供依据。方法对机械通气>48 h的79例患者的气管抽吸物(ETA)进行细菌定量培养和药敏测定。结果回顾性分析79例VAP患者ETA培养出病原菌214株,其中鲍曼不动杆菌79株(36.9%)。鲍曼不动杆菌对常见抗菌药物的耐药率呈上升趋势,出现较多多重耐药和泛耐药菌株。头孢哌酮/舒巴坦和亚胺培南的耐药率分别是55.6%和68.4%,均呈上升趋势。结论鲍曼不动杆菌是VAP常见病原菌之一,鲍曼不动杆菌的耐药性呈上升趋势,特别是多重耐药和泛耐药菌株,应引起高度重视。     

Interspecies transformation of Acinetobacter: genetic evidence for a ubiquitous genus

The availability of a strain of Acinetobacter competent for transformation has made it possible to demonstrate the genetic relatedness of a large variety of gram-negative, oxidase-negative, nonmotile, and aerobic coccobacilli originally classified into eleven different genera. Deoxyribonucleic acid (DNA) species from 265 such strains are capable of transforming stable auxotrophs of the competent Acinetobacter to prototrophy. The compositions of these DNA species vary from 40 to 46.8% guanine plus cytosine. Strains with widely differing phenotypic properties are also included in this collection of acinetobacters. DNA species from all oxidase-positive strains of Moraxella and from a variety of common bacteria are unable to transform the competent Acinetobacter. Although acinetobacters are usually considered to be unable to reduce nitrate to nitrite, six strains known to carry out this reduction have been shown to be authentic acinetobacters since their DNA species readily transform the competent Acinetobacter auxotrophs to prototrophy. In contrast to previous findings that acinetobacters rarely grow with glucose as a sole carbon source, the results of the present study show that 17 of the 265 strains grow readily in a glucosemineral medium, and 48 other strains can mutate spontaneously to grow in such a medium. A second competent strain of Acinetobacter, originally unable to use glucose, d-xylose, or d-ribose as carbon sources, has been transformed for ability to dissimilate these compounds using DNA species from strains that normally grow on these sugars. Although most of the 265 Acinetobacter strains studied were originally grown on complex media when isolated from human sources, only nine of these strains require growth factors in order to grow in a mineral medium containing a single carbon and energy source. A simple transformation assay has been devised for rapid examination of large numbers of strains to determine whether or not they are acinetobacters. This assay, which is suitable for routine diagnostic work, includes a procedure for preparation of crude transforming DNA from a small quantity of bacterial paste. Samples of DNA prepared from Acinetobacter cultures that had died on slants and plates were still able to effect transformation of the competent auxotrophs to prototrophy.     

The correct approach to community-acquired pneumonia in immunocompetent adults: review of current guidelines

Community-acquired pneumonia (CAP) often represents a clinical emergency requiring prompt and adequate antimicrobial treatment. The choice of antimicrobials, however, is difficult due to the variety of potential pathogens and to the spread of drug-resistance. Hence, a correct therapeutic approach should be based on the knowledge of the most frequently reported etiologies for the different clinical conditions, specific patient risk factors and the treatment setting (home, hospital, intensive or non intensive care unit) chosen accordingly. The awareness of the local drug-resistance epidemiology and individual patient characteristics, such as age, history of antibiotic treatments and related adverse events, underlying diseases, concurrent therapies and expected adherence to treatment should also be considered. Lastly, an adequate CAP management should address other issues, including therapy duration, monitoring of its efficacy and adverse effects, and supportive measures. The guidelines for CAP management aim to provide the physician with the necessary knowledge and criteria to assist him in these crucial decisions, and their adoption result in a significant reduction of mortality, frequency and length of hospitalization, and costs. Herein, the authors review and discuss some of the main current guidelines for CAP management, highlighting their differences and similarities.     

Differences in Acinetobacter baumannii strains and host innate immune response determine morbidity and mortality in experimental pneumonia

Despite many reports documenting its epidemicity, little is known on the interaction of Acinetobacter baumannii with its host. To deepen our insight into this relationship, we studied persistence of and host response to different A. baumannii strains including representatives of the European (EU) clones I-III in a mouse pneumonia model. Neutropenic mice were inoculated intratracheally with five A. baumannii strains and an A. junii strain and at several days morbidity, mortality, bacterial counts, airway inflammation, and chemo- and cytokine production in lungs and blood were determined. A. baumannii RUH875 and RUH134 (EU clone I and II, respectively) and sporadic strain LUH8326 resulted in high morbidity/mortality, whereas A. baumannii LUH5875 (EU clone III, which is less widespread than clone I and II) caused less symptoms. A. baumannii type strain RUH3023(T) and A. junii LUH5851 did not cause disease. All strains, except A. baumannii RUH3023(T) and A. junii LUH5851, survived and multiplied in the lungs for several days. Morbidity and mortality were associated with the severity of lung pathology and a specific immune response characterized by low levels of anti-inflammatory (IL-10) and specific pro-inflammatory (IL-12p40 and IL-23) cytokines at the first day of infection. Altogether, a striking difference in behaviour among the A. baumannii strains was observed with the clone I and II strains being most virulent, whereas the A. baumannii type strain, which is frequently used in virulence studies appeared harmless.     

Priapism: a review

Priapism is persistent penile erection in the absence of sexual stimulation. The pattern of blood flow to the penis that occurs during normal erection is altered so that sustained priapism may result in edema, increased risk of abrasion, tissue drying and necrosis of the penis. Numerous causes have been reported in animals and humans. The prognosis depends on the type of priapism and the amount of time that passes before therapeutic intervention. Surgical methods, such as aspiration and shunting procedures, have traditionally been used to treat priapism but carry a risk of postsurgical complications. Use of alpha-agonists for treatment of priapism in humans is often successful and avoids the risks of impotence and other surgical complications. Investigation of the use of alpha-agonists for treatment of priapism in animals should be considered.     

Characterisation of a siderophore from Acinetobacter calcoaceticus

Abstract The Gram-negatice bacterium Acinetobacter calcoaceticus was examined for production of siderophores and iron-repressible outer membrane proteins following growth in iron-restricted media. The iron chelator, 2,3-dihydroxybenzoic acid was identified in the culture supernatant bu ¹H nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry (MS). A group of outer membrane proteins between 80 and 85 kDa were induced under iron restriction.