No full-text available
To read the full-text of this research,
you can request a copy directly from the authors.
Asian Network for Surveillance of Resistant Pathogens (ANSORP) Study Group. Clinical outcomes and risk factors of community-acquired pneumonia caused by gram-negative bacilli
Abstract
To identify specific risk factors and clinical outcomes of community-acquired pneumonia (CAP) caused by gram-negative bacilli
(GNB), we compared the clinical features and outcomes of patients with CAP due to GNB with those of patients with non-GNB
pneumonia. We performed a prospective observational study of 912 cases of adult CAP in Asian countries from January 2002 to
December 2004. Systemic laboratory evaluation for determining the etiology and clinical evaluation were performed. Of 912
cases with CAP, 93 (10.1%) cases were caused by GNB: 59 with K. pneumoniae, 25 P. aeruginosa, 7 Enterobacter species, 1 Acinetobacter baumannii, and 1 Serratia marcescens. CAP caused by GNB was more frequently associated with septic shock, malignancy, cardiovascular diseases, smoking, hyponatremia,
and dyspnea, according to multivariate analysis (P < 0.05). Overall 30-day mortality rate was 7.3% (65/885). Mortality was significantly higher in the GNB group than in the
non-GNB group [18.3% (17/93) vs. 6.1% (48/792); P < 0.001]. GNB as a causative microorganism was found to be one of the independent risk factors for mortality (adjusted OR = 2.63,
95% CI 1.02–6.78, P = 0.046) with nursing home residence, mechanical ventilation, cardiovascular disease, respiratory rate > 30/min, and hyponatremia
(all P < 0.05). GNB was not only a frequent etiology of severe CAP but also an independent risk factor for mortality. Data suggest
that an initial empirical antimicrobial coverage of GNB including P. aeruginosa should be seriously considered in cases of severe pneumonia, especially in patients with underlying malignancy, underlying
cardiovascular diseases, smoking, septic shock, and hyponatremia.
... Prospective European studies have reported an overall GNB prevalence lower than 5% of all-CAP aetiologies. [28][29][30] However, some recent studies conducted in Asian countries reported higher prevalences, ranging from around 10% to 20% in China and Japan 22,27,[33][34][35]37 up to 30% in Taiwan. 36 The most frequent GNB isolated were P. aeruginosa, 28,33,37 K. pneumoniae 22,27,31,34,36 and E. coli. ...
... [28][29][30] However, some recent studies conducted in Asian countries reported higher prevalences, ranging from around 10% to 20% in China and Japan 22,27,[33][34][35]37 up to 30% in Taiwan. 36 The most frequent GNB isolated were P. aeruginosa, 28,33,37 K. pneumoniae 22,27,31,34,36 and E. coli. 29,32 The presence of HCAP, 28,30,[32][33][34]39 chronic respiratory disease 28,29,33 and aspiration 30,39 were the risk factors more strongly related to the presence of GNB CAP. ...
... 26 Several studies have reported increased mortality among patients suffering CAP due to GNB compared with those with another aetiologies. 27,29,32,[37][38][39] However, the presence of MDR-GNB and its impact on clinical outcomes have been poorly evaluated. Prina et al. demonstrated that the presence of P. aeruginosa, Enterobacter ESBL and methicillin-resistant S. aureus (MRSA) were independently associated with increased risk of 30-day mortality. ...
Respiratory infections are a major cause of global mortality and morbidity. In recent years, an increased incidence of multidrug-resistant (MDR) Gram-negative bacteria (GNB) has been described. Microorganisms such as Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae or Acinetobacter baumannii have been identified as causative pathogens of different respiratory tract infections. Several studies have detected MDR-GNB in patients with community-acquired and nosocomial pneumonia. Furthermore, MDR-GNB have also been isolated in patients with chronic obstructive pulmonary disease and bronchiectasis having acute or chronic bronchial infection. Prevalence varies depending on the geographical area but MDR-GNB has been reported in the Asia-Pacific region, Europe and the United States, reaching rates of 70% in hospital-acquired infection. The presence of MDR-GNB has been related to poor clinical outcomes, including increased mortality, although data regarding this relationship are limited. This is probably linked to inappropriate selection of empiric antibiotic treatment; this poses a threat of widespread resistance. GNB antibiotic resistance and the absence of new antibiotics are a major concern given limited treatment options; an aspect that deserves future research. We review current literature, highlight prevalence of MDR-GNB in different respiratory infections and explore their impact on clinical outcomes.
... 6 The presence of P. aeruginosa has been associated with more severe illness 7 and poorer clinical outcomes. [7][8][9][10] The antibiotic management for P. aeruginosa is different from the standard treatment that covers the most common microorganism causing CAP (e.g. Streptococcus pneumoniae), 11 and is extrapolated from ventilator-associated pneumonia (VAP) and health care-associated pneumonia (HCAP) data. ...
... These risk factors include structural lung diseases, such as bronchiectasis and repeated exacerbations of severe chronic obstructive pulmonary disease (COPD), leading to frequent steroid or antibiotic use or prior antibiotic therapy. 12 Guideline recommendations and the evidence to support the treatment regimen for CAP due to P. aeruginosa are based on observational studies, and limited by a small sample size [7][8][9][10] and the possibility of including patients with HCAP. 7,8 The aim of our study was to evaluate the risk factors for CAP due to P. aeruginosa and the impact of antimicrobial therapy in patients hospitalized with CAP due to P. aeruginosa. ...
... 12 Guideline recommendations and the evidence to support the treatment regimen for CAP due to P. aeruginosa are based on observational studies, and limited by a small sample size [7][8][9][10] and the possibility of including patients with HCAP. 7,8 The aim of our study was to evaluate the risk factors for CAP due to P. aeruginosa and the impact of antimicrobial therapy in patients hospitalized with CAP due to P. aeruginosa. ...
Current guidelines recommend empirical treatment against Pseudomonas aeruginosa in community-acquired pneumonia (CAP) patients with specific risk factors. However, evidence to support these recommendations is limited. We evaluate the risk factors and the impact of antimicrobial therapy in patients hospitalized with CAP due to P. aeruginosa.
We performed a retrospective population-based study of >150 hospitals. Patients were included if they had a diagnosis of CAP and P. aeruginosa was identified as the causative pathogen. Univariate and multivariate analyses were performed using the presence of risk factors and 30-day mortality as the dependent measures.
Seven hundred eighty-one patients with P. aeruginosa pneumonia were identified in a cohort of 62 689 patients with pneumonia (1.1%). Of these, 402 patients (0.6%) were included in the study and 379 (0.5%) were excluded due to health care-associated pneumonia or immunosuppression. In patients with CAP due to P. aeruginosa, 272 (67.8%) had no documented risk factors. These patients had higher rates of dementia and cerebrovascular disease. Empirical antibiotic therapy against P. aeruginosa within the first 48 h of presentation was independently associated with lower 30-day mortality in patients with CAP due to P. aeruginosa (hazard ratio (HR) 0.42, 95% confidence interval (CI): 0.23-0.76) and in patients without risk factors for P. aeruginosa CAP (HR 0.40, 95% CI: 0.21-0.76).
Risk factor recommended by current guidelines only detect one third of the patients admitted with CAP due to P. aeruginosa. Risk factors did not define the whole benefit observed due to empirical therapy covering P. aeruginosa.
Published 2015. This article is a U.S. Government work and is in the public domain in the USA.
... [34]. Установлено, что наиболее частыми возбудителями ТВП у пациентов, не отвечающих на стартовую антибактериальную терапию (АБТ) являются клебсиелла и синегнойная палочка, и вообще, выявление грамотрицательных бактерий в качестве этиологического агента ВП является независимым фактором риска летального исхода [58]. ...
... В целом по стране она составляет 78,8% [17,41,61]. Очевидную угрозу представляет распространение энтеробактерий, продуцирующих β-лактамазы расширенного спектра и метилрезистентные штаммы золотистого стафилококка [58]. ...
Thanks to a large number of studies on community-acquired pneumonia (CAP) by scientists around the world, new data are emerging on various aspects of the problem. Therefore, it is necessary to regularly update knowledge on this issue. Despite the tendency to decrease in recent years, the incidence of CAP is 5-10 cases per 1 thousand of the population. In the structure of the general morbidity of respiratory diseases, CAP ranks 2nd in the adult population and 1st in children. Mortality from CAP ranges from 5% to 25-50% depending on the severity, mechanisms of development and personality of the patient (age, nutritional status, concomitant diseases, immune system, etc.), increasing with the growth of diseases of the upper respiratory tract caused by pneumotropic viruses. The clinical lecture presents current data on the features of etiology, previously little known mechanisms of the pathogenesis of CAP, the clinic of typical bacterial, viral, fungal, mycoplasmic and parasitic CAP, as well as the features of the disease in patients with severe immune disorders (AIDS, other diseases/pathological conditions) and aspiration pneumonia. In short form there are discussed the main recommendations for the treatment of CAP in various clinical groups: outpatients, persons with mild CAP, patients with severe CAP with suspected infection with Pseudomonas aeruginosa and aspiration.
... While some previous studies have identified underlying pulmonary disease as a risk factor for GNB in CAP, 2,30 others have not. 1,7 A large proportion of our cohort had an underlying pulmonary condition. The most frequent pathogens in this group were H. influenzae and S. pneumoniae, regardless of whether the underlying condition was bronchiectasis or chronic bronchitis/asthma. ...
... Alcohol consumption was mainly associated with S. pneumoniae in our study. 7 Several GNB have been shown to cause necrotic pulmonary infections and cavitary lesions on the chest X-ray. 17,19 Even with the large proportion of TB cases in our cohort-a well-known phenomenon in countries with a high burden of TB-we did not observe an association with GNB. ...
Background:
In Western settings, community-acquired pneumonia (CAP) due to Gram-negative bacilli (GNB) is relatively rare. Previous studies from Asia, however, indicate a higher prevalence of GNB in CAP, but data, particularly from Southeast Asia, are limited.
Methods:
This is a prospective observational study of 1451 patients ≥15 y of age with CAP from two hospitals in Cambodia between 2007 and 2010. The proportion of GNB was estimated. Risk factors and clinical characteristics of CAP due to GNB were assessed using logistic regression models.
Results:
The prevalence of GNB was 8.6% in all CAP patients and 15.8% among those with a valid respiratory sample. GNB infection was independently associated with diabetes, higher leucocyte count and CAP severity. Mortality was higher in patients with CAP due to GNB.
Conclusions:
We found a high proportion of GNB in a population hospitalized for CAP in Cambodia. Given the complex antimicrobial sensitivity patterns of certain GNBs and the rapid emergence of multidrug-resistant GNB, microbiological laboratory capacity should be strengthened and prospective clinical trials comparing empiric treatment algorithms according to the severity of CAP are needed.
... Mycoplasma pneumoniae, Chlamydophila pneumoniae, Legionella spp.), and viruses. S. pneumoniae is the leading cause of CAP [Mü ller et al. 2010;Restrepo et al. 2010;Dambrava et al. 2008;Garcia-Vidal et al. 2008;Kang et al. 2008;Restrepo et al. 2008;Valencia et al. 2007;Carratala et al. 2005;Ruiz et al. 1999], and has also been identified as an important complication of severe and fatal cases of the 2009 H1N1 influenza virus infection along with S. aureus [CDC, 2010]. Gram-negative enteric bacilli, atypical zoonotic pathogens like Chlamydophila psittaci, Coxiella burnetii, and Francisella tularensis (tularemia), are uncommon causes of CAP [Dambrava et al. 2008]. ...
... Others risk factors associated with Pseudomonas infection are corticosteroid therapy 10 mg prednisone/day, broad-spectrum antibiotic therapy for 7 days in the past month, and malnutrition [Mandell et al. 2007]. Underlying malignancy, cardiovascular disease, and smoking are risk factors for Gram-negative pneumonia [Kang et al. 2008]. In a cohort of 3272 hospitalized CAP patients, history of COPD, current use of corticosteroids, prior antibiotic therapy, tachypnea 30/min, and septic shock on admission were associated with Gram-negative bacilli causing pneumonia, and these patients had a significantly longer hospital stay and increased mortality (36% versus 7%; p < 0.001) than those patients without these organisms [Falguera et al. 2009a]. ...
Community-acquired pneumonia (CAP) is a leading cause of morbidity and mortality worldwide, affecting approximately 5.6 million patients annually in the USA, where the annual cost exceeds US$12 billion. Optimal management should be based on knowledge of the most likely etiologic pathogens for each patient, based on an assessment of specific risk factors. It is also essential to assess severity of illness, to determine the appropriate site of care, and to order appropriate diagnostic testing. New developments in CAP management have focused on recognizing newly identified pathogens, such as methicillin-resistant Staphylococcus aureus and novel H1N1 influenza, understanding when to utilize new microbiological diagnostic techniques, and how to use biomarkers to direct the appropriate utilization of antibiotics and to define the duration of therapy. This paper reviews recent advances in our knowledge about the diagnosis and optimal management of CAP.
... One cell of Serratia is able to cause complete lysis in ten human erythrocytes within two hours in a liquid assay or haemolysis assay by suspending eryrthrocytes in citrate buffer (Marty et al., 2002). The community acquired pneumonia caused by gram negative bacilli was more frequently associated within septic shock, malignancy, cardiovascular disease, smoking, hyponatremia and dyspnea (Kang et al., 2008). The antimicrobial suspectibility profile of S. marcescens showed reduced susceptibility to ciproflacin, gentamicin, and piperacillin-tazobactam led an outbreak of multiple resistant S. marcescens (Knowles et al., 2000). ...
... Most of the studies for risk factors of pneumonia were hospital-based and represented only a small proportion of pneumonia cases. Few studies had focused on the risk factors that were associated with progression to severe or very severe pneumonia [6][7][8]. ...
Objective: To identify the risk factors for pneumonia and severe
pneumonia in children.
Design: Prospective cohort study.
Setting: Five tertiary-care teaching hospitals in India .
Participants: Children 2 to 59 months of age suffering from acute
respiratory infection (ARI).
Main outcome measures: Risk factors for the development of
WHO defined pneumonia and severe pneumonia.
Result: A total of 18159 children screened, and 7026 (39%)
children with ARI were enrolled. According to the WHO criteria,
938 (13.4%) and 6088 (86.6%) of the enrolled children had
pneumonia and no pneumonia, respectively. Out of 938 children
with pneumonia, 347 (36.9%) had severe pneumonia. On
univariate analysis, younger age, male gender and low weight for
height, were significant risk factors for pneumonia. On
multivariate analysis, one-unit increase in age in months (OR =
0.97; 95% CI: 0.97-0.98) and weight for height z-score (OR =
0.76; 95% CI: 0.72-0.79) had a protective effect.
Conclusions: Young age and undernutrition (low weight for
height/length) in children are significant independent risk factors
for pneumonia.
... Так, наиболее частыми возбудителями тяжелой ВП у пациентов, не ответивших на стартовую анти бактериальную терапию и нуждающихся в искусст венной вентиляции легких, в исследовании C.L.Wu et al. являлись K. рneumoniae (25 %) и P. aeruginosa (22,5 %) [22]. В другой работе наличие грамотрица тельных палочек в качестве этиологического агента ВП являлось независимым фактором риска леталь ного исхода [23]. Аналогичная связь была продемон стрирована в работе F. Paganin et al.: тяжелая ВП, ассоциированная с K. рneumoniae, сопровождалась до стоверно более высокой летальностью по сравнению с ВП пневмококковой этиологии [24]. ...
... In that publication, however, P. aeruginosa failed to be an independent predictor of death. 25 Similar effect on mortality related to GNB was found in Asian countries 27 and South America. 28 Unfortunately, there are no specific measures to prevent pneumonia caused by GNB in the community setting. ...
Early introduction of appropriate antibiotherapy is one of the major prognostic-modifying factors in community acquired pneumonia (CAP). Despite established guidelines for empirical therapy, several factors may influence etiology and, consequently, antibiotic choices. The aims of this study were to analyze the etiology of CAP in adults admitted to a northern Portugal University Hospital and evaluate the yield of the different methods used to reach an etiological diagnosis, as well as analyze of the impact of patient demographic and clinical features on CAP etiology.
We retrospectively analyzed 1901 cases of CAP with hospitalization. The diagnostic performance increased significantly when blood and sputum cultures were combined with urinary antigen tests. The most frequent etiological agent was Streptococcus pneumoniae (45.7%), except in August, when it was overtaken by gram-negative bacilli (GNB) and Legionella pneumophila infections. Viral infections were almost exclusive to winter and spring. A negative microbiological result was associated with increasing age, non-smoking and lack of both blood/sputum cultures. Younger age was a predictor for S. pneumoniae, Influenza and L. pneumophila infections. Active smoking without any previously known respiratory disease was a risk factor for legionellosis. COPD was associated with Haemophilus influenzae cases, while dementia was typical in GNB and S. aureus patients. Diabetes mellitus (DM) and heart disease were negative predictors of S. pneumoniae and H. influenzae, respectively. P. aeruginosa was an independent risk factor for mortality (OR 13.02, 95% CI 2.94–57.7).
This study highlights the importance of a comprehensive microbiological diagnostic workup and provides clues to predicting the most probable CAP causative agents, based on a patient's clinical profile. These may be taken into account when establishing first line antibiotherapy.
... 17,20,24,26,28,31 The median prevalence for Enterobacteriaceae CAP is 3.9% (range: 0.9-19%) in CAP patients and 11.9% (range: 1.6-37.9%) in patients with culture positive CAP. 3,[15][16][17][18][19][20][23][24][25][26][27][28][29][30][31][32][33][34][35] The incidence of Enterobacteriaceae is two to three folds higher in patients in the ICU setting compared with patients in non-ICU settings. 53,61 Of note, the rate is insignificant in ambulatory patients helping the clinician to focus the concern of this group of pathogen only to those in the hospital setting. ...
In recent decades, there has been a growing interest about the role of gram negative bacteria in community-acquired pneumonia (CAP), especially Pseudomonas aeruginosa, Enterobacteriaceae, and Acinetobacter baumannii. The prevalence of these pathogens differs largely according to the local ecology and the geographical location. Identifying gram negative bacteria, and in particular resistant gram negative bacteria, is of paramount importance in patients with CAP because these pathogens are associated with higher clinical severity and unfavorable outcomes. The use of individualized risk factors to predict each pathogen is a helpful strategy that needs to be locally validated. However, it should be taken into account that most of the risk factors identified in the literature are heterogeneously defined or lack consistency. New diagnostic techniques, such as molecular testing, are promising methods for early detection of these gram negative pathogens. The increasing mechanisms of resistance to antibiotics of these pathogens have limited our therapeutic approach. This narrative review focuses on the epidemiology, risk factors, diagnosis, and therapeutic options for the most relevant gram negative bacteria that cause CAP.
... Pneumonia due to P aeruginosa occurs in several distinct syndromes such as community-acquired pneumonia (CAP) and bacteremia in neutropenic hosts, and in intubated patients [12] In CAP, coverage of P aeruginosa is controversial due to the different rates of prevalence reported in the literature [13][14][15][16][17][18]. Factors such as structural lung diseases (especially bronchiectasis), repeated exacerbations of severe chronic obstructive pulmonary disease (COPD), chronic oral steroid administration, alcoholism and frequent (> 4 courses per year) or recent antibiotic therapy have been associated with P aeruginosa isolates [1,2,4,19]. ...
Background:
Antipseudomonal antibiotics should be restricted to patients at risk of Pseudomonas aeruginosa infection. However, the indications in different guidelines on community-acquired pneumonia (CAP) are discordant. Our objectives were to assess the prevalence of antipseudomonal antibiotic prescriptions and to identify determinants of empirical antibiotic choices in the emergency department.
Methods:
Observational, retrospective, one-year cohort study in hospitalized adults with pneumonia. Antibiotic choices and clinical and demographic data were recorded on a standardized form. Antibiotics with antipseudomonal activity were classified into two groups: a) β-lactam antipseudomonals (β-APS), including carbapenems, piperacillin / tazobactam or cefepime (in monotherapy or combination) and b) monotherapy with antipseudomonal quinolones.
Results:
Data were recorded from 549 adults with pneumonia, with Pseudomonas aeruginosa being isolated in only nine (1.6%). Most (85%) prescriptions were compliant with SEPAR guidelines and 207 (37%) patients received antibiotics with antipseudomonal activity (14% β-APS and 23% levofloxacin). The use of β-APS was independently associated with ICU admission (OR 8.16 95% CI 3.69-18.06) and prior hospitalization (OR 6.76 95% CI 3.02-15.15), while levofloxacin was associated with negative pneumococcal urine antigen tests (OR 3.41 95% CI 1.70-6.85) but negatively associated with ICU admission (OR 0.26 95% CI 0.08-0.86). None of these factors were associated with P aeruginosa episodes. In univariate analysis, prior P aeruginosa infection/colonization (2/9 vs 6/372, p = 0.013), severe COPD (3/9 vs 26/372, p = 0.024), multilobar involvement (7/9 vs 119/372, p = 0.007) and prior antibiotic (6/9 vs 109/372, p = 0.025) were significantly associated with P aeruginosa episodes.
Conclusions:
Antipseudomonal prescriptions were common, in spite of the very low incidence of Pseudomonas aeruginosa. The rationale for prescription was influenced by both severity-of-illness and pneumococcal urine antigen test (levofloxacin) and prior hospitalization and ICU admission (β-APS). However, these factors were not associated with P aeruginosa episodes. Only prior P aeruginosa infection/colonization and severe COPD seem to be reliable indicators in clinical practice.
... The page number in the footer is not for bibliographic referencing www.tandfonline.com/ojid 10 underlying malignancy or cardiovascular disease and structural lung disease e.g., cystic fibrosis (13). ...
... Similarly, the likely pathogen involved is also determined by the associated co-morbidity and age of the patient [1]. K. pneumoniae is among the common gram-negative bacteria encountered by physicians worldwide and is frequent etiology of severe CAP cases [3,4]. Moreover, it has been proven to be an independent risk factor for mortality in severe CAP cases. ...
... Five cases of CAP caused by A. baumannii have been reported in Korea; in all cases, A. baumannii was identified in sputum cultures, blood cultures, or biopsy. Fortunately, the A. baumannii was susceptible to piperacillin/tazobactam, ceftazidime, cefepime, meropenem, and tobramycin [9][10][11][12][13]. In our case, susceptibility tests showed that the A. baumannii was resistant to piperacillin/tazobactam, ceftazidime, cefepime, imipenem, meropenem, and tobramycin but susceptible to colistin, tigecycline, minocycline, amikacin, and gentamicin. ...
Acinetobacter baumannii is an aerobic Gram-negative coccobacillus that causes nosocomial pneumonia in patients on mechanical ventilation or previously treated with broad-spectrum antibiotics. Nevertheless, community-acquired pneumonia (CAP) caused by A. baumannii, especially multi-drug resistant (MDR) strains, is rare. We experienced the first case of CAP caused by MDR A. baumannii in Korea in a 78-year-old man. This case shows that MDR A. baumannii can cause CAP in Korea.
... Anaerobic bacteria may cause pneumonia particularly in patients at increased risk of aspiration. Pseudomonas aeruginosa is another uncommon bacterial cause of CAP and may be considered in individuals with severe pneumonia, especially those with underlying malignancy or cardiovascular disease and structural lung disease e.g., cystic fibrosis (13). ...
... P. aeruginosa has been recognized as an infrequent cause of CAP with an incidence between 0.4 and 6.9% in patients who require hospitalization and it is considered a more severe illness with poor clinical outcomes [76,[86][87][88]. ...
Purpose of review:
The increase in drug-resistant community-acquired pneumonia (CAP) is an important problem all over the world. This article explores the current state of antimicrobial resistance of different bacteria that cause CAP and also assesses risk factors to identify those pathogens.
Recent findings:
In the last two decades, it has been documented that there is a significant increase in drug-resistant Streptococcus pneumoniae and other bacteria causing CAP. The most important risk factors are overuse of antibiotics, prior hospitalization, and lung comorbidities. The direct consequences can be severe, including prolonged stays in hospital, increased costs, and morbi-mortality. However, drug-resistant CAP declined after the introduction of the pneumococcal conjugate vaccine. This review found an increase in resistance to the antibiotics used in CAP, and the risk factor can be used for identifying patients with drug-resistant CAP and initiate appropriate treatment. Judicious use of antibiotics and the development of effective new vaccines are needed.
... Although these tools are more objective measures than dyspnea, the latter symptom is easily assessed. In previous studies, dyspnea has been observed more frequently in pneumococcal pneumonia than in pneumonia due to atypical pathogens (17), in CAP caused by Gram-negative bacilli versus other types of pathogens (18), and in CAP with asthma versus CAP without asthma (19). These earlier findings suggested the potential role of dyspnea as a predictor of mortality. ...
Objective:
The optimal prognostic model for community-acquired pneumonia (CAP) remains unclear. In this study, we sought to identify independent predictors of 30-day mortality in patients with CAP and to determine whether adding specific prognostic factors to each of the two clinical prediction scores could improve the prognostic yield.
Methods:
This retrospective study involved 797 CAP patients who had been hospitalized at a tertiary referral center. The patients were categorized into two groups: those who survived and those who had died on or before 30 days after admission. Select clinical parameters were then compared between the two groups.
Results:
During the 30-day period, there were 72 deaths (9%). We constructed two models for a multivariate analysis: one was based on a high CURB-65 score (3-5) and the other on a high pneumonia severity index (PSI) class (V). In both models, a high CURB-65 score or a high PSI class, along with the presence of dyspnea, high Eastern Cooperative Oncology Group (ECOG) performance status (3-4), and a low serum albumin level, were independent predictors of 30-day mortality. In both the CURB-65-based and PSI-based models, the addition of dyspnea, high ECOG performance status, and hypoalbuminemia (<3 g/dL) enhanced the prognostic assessment, and subsequently, the c-statistics calculated with the use of three- or four- predictor combinations exceeded 0.8.
Conclusion:
In addition to the CURB-65 or PSI, the clinical factors of dyspnea, the ECOG performance status, and serum albumin level may be independent predictors of 30-day mortality in CAP patients. When combined with the CURB-65 or PSI, these parameters provide additional evidence for predicting poor prognoses.
... Similarly, the authors found that chronic respiratory disease and enteral tube feeding administration were independent risk factors for P. aeruginosa pneumonia. Other studies have evaluated risk factors for P. aeruginosa pneumonia infection along with other Gramnegative bacilli [41,42]. ...
Purpose of review:
Identification of patients with multidrug-resistant (MDR) pathogens at initial diagnosis is essential for the appropriate selection of empiric treatment of patients with pneumonia coming from the community. The term Healthcare-Associated Pneumonia (HCAP) is controversial for this purpose. Our goal is to summarize and interpret the data addressing the association of MDR pathogens and community-onset pneumonia.
Recent findings:
Most recent clinical studies conclude that HCAP risk factor does not accurately identify resistant pathogens. Several risk factors related to MDR pathogens, including new ones that were not included in the original HCAP definition, have been described and different risk scores have been proposed. The present review focuses on the most recent literature assessing the importance of different risk factors for MDR pathogens in patients with pneumonia coming from the community. These included generally MDR risk factors, specific risk factors related to methicillin-resistant Staphylococcus aureus or Pseudomonas aeruginosa and clinical scoring systems develop to assess the MDR risk factors and its application in clinical practice.
Summary:
Different MDR risk factors and prediction scores have been recently developed. However, further research is needed in order to help clinicians in distinguishing between different MDR pathogens causing pneumonia.
... One cell of Serratia is able to cause complete lysis in ten human erythrocytes within two hours in a liquid assay or haemolysis assay by suspending eryrthrocytes in citrate buffer (Marty et al., 2002). The community acquired pneumonia caused by gram negative bacilli was more frequently associated within septic shock, malignancy, cardiovascular disease, smoking, hyponatremia and dyspnea (Kang et al., 2008). The antimicrobial suspectibility profile of S. marcescens showed reduced susceptibility to ciproflacin, gentamicin, and piperacillin-tazobactam led an outbreak of multiple resistant S. marcescens (Knowles et al., 2000). ...
Among the 100 isolates, a bacterial strain TW1 was isolated from the urine tract specimens of infected women admitted at Government hospital, Namakkal District in Tamil Nadu, India, using caprylate thallious agar medium. The organism was characterized by all biochemical tests and showed similarity with Serratia marcescens. The genomic level confirmation done with 16s rDNA primer by submitting the genomic sequence to Gene Bank under ACC.No-GU046545 after comparing, showed 98% sequence similarity with S. marcescens and thus, the strain was named Serrtia marcescens TW1.
... However, most of the published P aeruginosa CAP studies are limited by single-center design and relatively small sample sizes. 13,29,30 The use of ICD-9-CM codes enabled us to obtain signifi cant amounts of information from a large national cohort of patients in a closed health system, which is a major strength of this study. The process of medical coding introduces opportunities for human error, but the use of ICD-9-CM codes for selecting patients with pneu monia has favorable positive and negative predictive values (85.5% and 97.2%, respectively), indicating a relatively low likelihood of misclassifi cation. ...
Several studies described a clinical benefit of macrolides due to their immunomodulatory properties in different respiratory diseases. We aim to assess the effect of macrolide therapy on mortality for patients hospitalized due to Pseudomonas aeruginosa Community-acquired pneumonia (CAP).
We performed a retrospective population-based study of >150 hospitals in the US Veterans Health Administration. Patients were included if they had a diagnosis of CAP and P. aeruginosa was identified as the causative pathogen. Patients with healthcare-associated pneumonia and immunosuppression were excluded. Macrolide therapy was considered when administered in the first 48 hours of admission. Univariate and multivariable analyses were performed using 30-day mortality as the dependent measure.
We included 402 patients with P. aeruginosa CAP. 171 patients (42.5%) received a macrolide during the first 48 hours of admission. These patients were older and white. Macrolide use was not associated with lower 30-day mortality (HR 1.14, 95% CI 0.70-1.83, p=0.5). In addition, macrolide treated patients had no differences in ICU admission, use of mechanical ventilation, use of vasopressors and length of stay (LOS), when compared to patients that did not receive macrolides. A subgroup analyses among ICU P. aeruginosa CAP patients showed no differences on baseline characteristics and outcomes.
Macrolide therapy in the first 48 hours of admission is not associated with decreased 30-day mortality, ICU admission, need for mechanical ventilation and LOS in P. aeruginosa CAP hospitalized patients. Further larger cohort studies research should address the benefit of macrolides as immunomodulators in patients with P. aeruginosa CAP.
... Deze risicofactoren zijn echter vooral bij ziekenhuispatiënten onderzocht en dus niet per se representatief voor alle pneumoniepatiënten. [5][6][7] In de schaarse onderzoeken in de eerstelijnsgezondheidszorg zijn wel onafhankelijke risicofactoren gevonden: hogere leeftijd, roken, contact met kinderen, COPD, astma, een voorgeschiedenis van pneumonie en eerdere luchtweginfecties. 8,9 In die onderzoeken ging het dan weer vooral om oudere patiënten. ...
Teepe J, Grigoryan L, Verheij T. Risicofactoren voor pneumonie bij kinderen en jongvolwassenen. Huisarts Wet 2011;54(2):56–9.
Achtergrond Buiten het ziekenhuis opgelopen longontstekingen, community-acquired pneumonieën (CAP), komen veel voor bij kinderen en jongvolwassenen, en zijn vooral bij jonge kinderen soms levensbedreigend.
In de huisartsenpraktijk is wel onderzoek gedaan naar de risicofactoren voor CAP, maar dat onderzoek richtte zich vooral op
oudere patiënten.
Methode Wij hebben met een patiënt-controleonderzoek geprobeerd de determinanten van CAP bij kinderen en jongvolwassenen te
bepalen. Onze patiënten waren 107 kinderen (0–15 jaar) en 156 jongvolwassenen (16–40 jaar) bij wie tussen 1998 en 2008 de
diagnose pneumonie was gesteld. Voor elke patiënt selecteerden we drie controlepersonen uit dezelfde leeftijdsgroep. Met behulp
van logistische regressieanalyse zijn we vervolgens nagegaan welke kenmerken samenhingen met het optreden van een pneumonie.
Resultaten Bij kinderen bleken lagere leeftijd, astma en eerder doorgemaakte bovensteluchtweginfecties onafhankelijke risicofactoren
voor pneumonie. Bij jongvolwassenen waren dit hogere leeftijd, astma, drie of meer kinderen thuis, huidig roken en drie of
meer doorgemaakte bovensteluchtweginfecties.
Conclusie Drie van de genoemde bevindingen zijn opmerkelijk. Ten eerste dat de kans op een CAP ook voor jongvolwassenen al
stijgt met de leeftijd, ten tweede dat die kans eveneens groter wordt als er jonge kinderen in huis zijn, en ten derde dat
herhaalde bovensteluchtweginfecties zowel voor kinderen als voor jongvolwassenen de kans op een pneumonie verhogen, mogelijk
omdat zij de infectiegevoeligheid vergroten. Hoe deze factoren de etiologie van CAP precies beïnvloeden is echter nog onvoldoende
duidelijk. Dat zou nader onderzocht moeten worden om diagnostiek en behandeling te kunnen verbeteren.
... Identifying risk factors is important for improving insight into the aetiology of pneumonia and permitting adequate and timely diagnosis. Most risk factors for CAP have been derived from studies that included hospitalised patients, representing only a small proportion of pneumonia cases [5][6][7]. The few available studies in primary care found increasing age, cigarette smoking, contact with children, chronic bronchitis, asthma, a history of pneumonia and previous respiratory infection to be independent risk factors for CAP [8,9]. ...
Most studies on determinants of community-acquired pneumonia (CAP) in primary care have focused primarily on the elderly. Using a case–control study in four Dutch healthcare centres, determinants of CAP among children and young adults were identified.
Cases included 156 young adults (aged 16–40 yrs) and 107 children (aged 0–15 yrs) diagnosed with CAP during 1999–2008. For each case, three controls were selected from the same age group. Separate logistic regression analyses were used to identify determinants in young adults and children.
Lower age, asthma and previous upper respiratory tract infections (URTIs) were independently associated with CAP in children. Increasing age, asthma, three or more children at home, current smoking and three or more previous URTIs were independent determinants of CAP in young adults.
The present study has three remarkable findings: 1) increasing age was an independent determinant of CAP in young adults; 2) having young children increased the risk of the development of CAP in young adults; and 3) the number of previous URTIs was independently associated with CAP in both children and young adults, possibly due to higher infection susceptibility. Further studies are required in order to better understand the aetiology of CAP and permit better diagnosis and treatment of this serious condition.
... 14,15 The final clinical outcome was mortality, with the use of mechanical ventilation as one significant independent risk factor for fatality. [16][17][18] We hypothesized that schizophrenia was associated with greater risk of adverse clinical outcomes. ...
Despite the recent attention to patient safety and quality of care, no prior studies have addressed outcomes of hospitalization for pneumonia among patients with schizophrenia. This study investigated the extent to which clinical outcomes of pneumonia were different among patients with schizophrenia. This study used data from the Taiwan National Health Insurance Research Database. Of the total of 81,599 patients admitted with a principal diagnosis of pneumonia from 2002 to 2004, 949 had previously been admitted with a principal or secondary diagnosis of schizophrenia within the 2 years of their index pneumonia admission. We randomly selected 2847 pneumonia patients matched with the study group in terms of gender, age, year of admission, length of stay, and Charlson Comorbidity Index score as the comparison cohort. Conditional logistic regression models were used for analysis. Findings indicated a higher prevalence of adverse outcomes among patients with schizophrenia. Patients with schizophrenia were independently associated with a 1.81 times greater risk of intensive care unit admission (95% confidence interval [CI] = 1.37-2.40), a 1.37 times greater risk of acute respiratory failure (95% CI = 1.08-1.88), and a 1.34-fold greater risk of mechanical ventilation (95% CI = 1.04-1.92) after adjusting for characteristics of patients, physicians, hospitals, and potential clustering effects. Adjusted odds ratios were further evident among those treated in private hospitals and in regional/district hospitals. Significant barriers to prompt and appropriate medical care for pneumonia persist for patients with schizophrenia. Careful monitoring of physical health and proper integration between psychiatrists and physicians should be stressed to reduce poor clinical outcomes in this vulnerable population.
... coamoxiclav) as well as second generation cephalosporins. CAP due to Gram-negative organisms tends to be more severe than other causes of CAP, 19 emphasizing the importance of appropriate empirical therapy. Furthermore, in 25-70% of cases of CAP no microbiological diagnosis can be found, and in Europe these cases are assumed to be mainly due to S. pneumoniae. ...
... These include all pathogens which are only rarely implicated (mainly in at-risk populations), and which are associated with considerable pathogenicity but require a very different antimicrobial coverage, such as Enterobacteriaceae (EB) and Pseudomonas aeruginosa (PA). A landmark Spanish study found these pathogens in ,10% of the study population [2], a finding confirmed in a recent Korean study [3]. In contrast, others found these pathogens in ,1-3% [4][5][6][7]. ...
The aim of the present study was to determine the relevance of the presence of Enterobacteriaceae (EB) and Pseudomonas aeruginosa (PA) in patients with community-acquired pneumonia (CAP) and how the true incidence of these pathogens can be assessed.
Based on prospective data from 5,130 patients with CAP included in the German Competence Network for Community-Acquired Pneumonia (CAPNETZ), the incidence, clinical characteristics, outcome and predictors of patients with CAP due to EB and PA were studied applying strict case definitions.
The incidence of EB was 67 (1.3%) out of 5,130, including 27 patients with bacteraemia. PA was found in 22 (0.4%) out of 5,130 patients. These microorganisms were judged to be indeterminate pathogens in an additional 172 and 27 isolates, respectively. Patients with indeterminate pathogens differed considerably from those with definite isolates in terms of clinical presentation, comorbidity, pneumonia severity and outcome. Independent risk factors for EB included cardiac and cerebrovascular disease, and for PA chronic respiratory disease and enteral tube feeding. The 30-day mortality was significantly higher in patients with definite pathogens.
In the present large population, the incidence of CAP due to EB/ PA was low. The risk of the presence of these pathogens can be assessed using several predictors, which may identify those patients in need of an extended diagnostic work-up and initial antimicrobial treatment.
Objective
To identify the risk factors for pneumonia and severe pneumonia in children.DesignProspective cohort study.SettingFive tertiary-care teaching hospitals in India.ParticipantsChildren 2 to 59 months of age suffering from acute respiratory infection (ARI).Main outcome measuresRisk factors for the development of WHO defined pneumonia and severe pneumonia.ResultA total of 18159 children screened, and 7026 (39%) children with ARI were enrolled. According to the WHO criteria, 938 (13.4%) and 6088 (86.6%) of the enrolled children had pneumonia and no pneumonia, respectively. Out of 938 children with pneumonia, 347 (36.9%) had severe pneumonia. On univariate analysis, younger age, male gender and low weight for height, were significant risk factors for pneumonia. On multivariate analysis, one-unit increase in age in months (OR = 0.97; 95% CI: 0.97–0.98) and weight for height z-score (OR = 0.76; 95% CI: 0.72–0.79) had a protective effect.Conclusions
Young age and undernutrition (low weight for height/length) in children are significant independent risk factors for pneumonia.
Renal infections have a spectrum of presentations, varying from minimal symptoms or asymptomatic to frank sepsis and septic shock. Urinary tract infections (UTI) are among the most common human infections and add substantial morbidity and financial burden on society. The common pathologies include acute and chronic bacterial pyelonephritis, emphysematous pyelonephritis, xanthogranulomatous pyelonephritis, renal abscess, pyonephrosis, and genitourinary tuberculosis involving the kidney. Advances in the understanding of the microbiology and the pathophysiology of UTI have improved the management of renal infections, with introduction of more effective antibiotics and better and judicious usage of drugs and combinations of endoscopic, percutaneous, or surgical interventions. In this chapter, the authors review the common pathologies and their management.
Community-acquired pneumonia refers to an infection of the lung parenchyma acquired outside a healthcare setting. The term severe CAP (SCAP) signifies a more serious form of community-acquired pneumonia that requires admission to the intensive care unit and has a high risk of mortality. SCAP is an important cause of morbidity and mortality in both the developed and the developing world. The common causative pathogens of SCAP include pneumococcus, Hemophilus influenzae, and atypical bacterial organisms, and less commonly, gram-negative bacilli and Staphylococcus aureus, particularly in hosts with risk factors for these pathogens. An initial diagnosis can usually be made clinically based on the presentation, and confirmed with the help of a chest radiograph. Scoring systems may be used to assess the severity, mortality risk and requirement of admission to the intensive care unit. Empirical antibiotic treatment must be instituted at the earliest after sending blood and respiratory samples for microbiological analysis and antibiotics may be changed according to the results. Supportive and adjunctive treatments are instituted, as required. Personalized management based on various novel strategies may improve the management of SCAP in the future. In this chapter, we present a detailed discussion of the epidemiology, pathogenesis, diagnostic evaluation and treatment of SCAP.
Available online
This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause.
The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal
INTRODUCTION: Non-classical pathogens including Klebsiella spp. have been observed infrequently as part of large cystic fibrosis (CF) cohort studies, but there are sparse data regarding their impact on clinical outcomes.
OBJECTIVES: This study was conducted to elucidate the clinical impact of Klebsiella species infections in CF patients.
METHODS: Adult patients attending a Canadian CF clinic with Klebsiella spp. positive sputum cultures from 1978–2013 were assessed. Infection was categorized as transient or prolonged (≥50% positive cultures in one year). Rates of pulmonary exacerbations (PEx) at incident infection and risk factors for developing prolonged infections were determined. Isolates were genotyped and tested for antibiotic susceptibility and hypermucoviscosity.
RESULTS: Thirty unique infections among 25 patients (8% of clinic population) were detected, in which 9 K. pneumoniae, 17 K. oxytoca and 4 K. ozaenae species were identified. Four patients developed prolonged infection, however, all but one subsequently cleared. Incident infection was associated with increased risk of PEx compared to clinic visits before but not after isolation. Patients progressing to prolonged infections did not differ in demographics, comorbidities or treatments, compared to transiently infected individuals. Hypermucoviscosity and multi-drug resistance were uncommon. Individuals were infected with only single strains of Klebsiella at a time and no evidence of cross infection was observed.
CONCLUSIONS: Klebsiella infections are rare at any individual time point in CF. However, they are observed in almost 10% of a patient cohort followed longitudinally and are not clearly associated with either acute or sub-acute clinical deterioration.
Pneumonia is a leading cause of death worldwide, ranking third both globally and in Taiwan. This guideline was prepared by the 2017 Guidelines Recommendations for Evidence-based Antimicrobial agents use in Taiwan (GREAT) working group, formed under the auspices of the Infectious Diseases Society of Taiwan (IDST). A consensus meeting was held jointly by the IDST, Taiwan Society of Pulmonary and Critical Care Medicine (TSPCCM), the Medical Foundation in Memory of Dr. Deh-Lin Cheng, the Foundation of Professor Wei-Chuan Hsieh for Infectious Diseases Research and Education and CY Lee's Research Foundation for Pediatric Infectious Diseases and Vaccines. The final guideline was endorsed by the IDST and TSPCCM. The major differences between this guideline and the 2007 version include the following: the use of GRADE methodology for the evaluation of available evidence whenever applicable, the specific inclusion of healthcare-associated pneumonia as a category due to the unique medical system in Taiwan and inclusion of recommendations for treatment of pediatric pneumonia. This guideline includes the epidemiology and recommendations of antimicrobial treatment of community-acquired pneumonia, hospital-acquired pneumonia, ventilator-associated pneumonia, healthcare-associated pneumonia in adults and pediatric pneumonia.
Community-acquired pneumonia is common and important infectious disease in adults. This work represents an update to 2009 treatment guideline for community-acquired pneumonia in Korea. The present clinical practice guideline provides revised recommendations on the appropriate diagnosis, treatment, and prevention of community-acquired pneumonia in adults aged 19 years or older, taking into account the current situation regarding community-acquired pneumonia in Korea. This guideline may help reduce the difference in the level of treatment between medical institutions and medical staff, and enable efficient treatment. It may also reduce antibiotic resistance by preventing antibiotic misuse against acute lower respiratory tract infection in Korea.
Pseudomonas aeruginosa is a significant causative bacterium in hospital-acquired pneumonia and nursing and healthcare-associated pneumonia, but it seems to be rare in community-acquired pneumonia (CAP). We report two cases of severe CAP due to P. aeruginosa. Case 1: A 52-year-old man was referred to our hospital for chest and back pain. He was being treated for diabetes mellitus and had a long history of smoking. Chest images showed consolidation in the right upper lobe. Soon after hospitalization, he developed sepsis shock and died seven hours later. Case 2: A 73-year-old man with a history of heavy smoking was referred to our hospital for right chest pain. Chest images showed right upper lobe pneumonia. Although wide-spectrum antimicrobial agents were administrated, he died ten hours after admission. In both cases, there was a rapid progression to death, despite administration of a broad spectrum of antibiotics and treatment for sepsis. In cases of CAP involving the right upper lobe, the possibility of bacteremia and rapid progress should be considered.
Book chapter discussing the epidemiology, etiology, diagnosis, treatment, and prevention of acute pneumonia.
The aim of our study was to determine the bacteriological and clinical profile of community acquired pneumonia patients requiring hospital admission. CAP was defined as per BTS guidelines. 65/104 cases of study group turned out to be culture positive for definitive bacterial etiology. The Commonest cause for CAP was Streptococcus pneumoniae (19/65) followed by, Klebsiella pneumoniae (17/65), Staphylococcus aureus (13/65), Pseudomonas aeruginosa (8/65), Escherichia coli (4/65), Acinetobactor spp. (3/65). Smoking (52%) and chronic alcoholism (28%) were major risk factors and COPD (23%) and Diabetes mellitus (19%) were major co-morbidities associated with CAP in the study group. The mortality was 8% cases after therapy and Pseudomonas aeruginosa was commonest cause of it. Death occurred exclusively in elderly people, all of whom were suffering from co- morbidities and had an initial CURB-65 a score of three. Limitation of our study was the inability to isolate atypical micro organisms. This emphasizes the need for further studies.
Acinetobacter baumannii is a significant pathogen in nosocomial infections, especially in intensive care units. However, community-acquired A. baumannii (CAAB) pneumonia is an uncommon disease. Most of the CAAB pneumonia in the literature is characterized by an abrupt onset and rapid progression to respiratory failure and hemodynamic instability. In our case, a 51-year-old man without underlying diseases developed severe pneumonia. Respiratory distress rapidly worsened and mechanical ventilation was applied. Extra-corporeal membrane oxygenation was applied due to refractory septic shock. Fully sensitive A. baumannii pneumonia was confirmed by the sputum culture and blood culture. The patient was effectively treated by the meropenem. However, the patient died of uncontrolled ventilator-associated pneumonia, developed on the 10th hospital day, and refractory septic shock. We report the case of severe CAAB pneumonia with bacteremia in a patient without underlying diseases in Korea.
Acinetobacter baumannii infections have become significant pathogen in hospitalized patients, especially in the intensive care unit setting. Community-acquired Acinetobacter meningitis in adults is a very rare infection of the central nervous system. Most community-acquired Acinetobacter infections have been reported from countries with a tropical or subtropical climate. Acinetobacter infections mainly affect patients with some form of comorbidity and are also associated with heavy smoking and excess alcohol consumption. In our case, a 62-year-old male patient with DM, hypertension, and excess alcohol consumption developed meningitis. Bulging membrane and inflammation were observed in the right ear. A. baumannii meningitis was confirmed by blood, CSF, and ear discharge culture. The patient was treated effectively with meropenem for 21 days. After antibiotic treatment, follow-up cultures of CSF, blood, and ear discharge showed a negative result, and the CSF cell profile was normalized. However, the patient died of recurrent pneumonia on hospital day 45. We report on a case of community-acquired Acinetobacter meningitis in an adult in Korea.
Acinetobacter baumannii (A. baumannii) has emerged as one of the most problematic pathogens for health care institutions globally. Its ability to survive for prolonged periods throughout a hospital environment acting in synergy with the emerging resistance profile potentiates its ability for nosocomial spread. The organism commonly targets the most vulnerable hospitalized patients, those who are critically ill. Hospital-acquired pneumonia is still the most common infection caused by this organism. However, in more recent times, bloodstream infections and infections involving the skin and soft tissue, urinary tract and central nervous system, have emerged as highly problematic for some institutions. A. baumannii community-acquired pneumonia is a distinct clinical syndrome in tropical areas.
Reported strains resistant to all known antibiotics make A. baumannii one of the organisms threatening the current antibiotic era. Given the range and diversity of resistance determinants identified in this specie, antibiotics selection for empirical treatment is challenging. Carbapenems have been thought of as the agents of choice; however, the clinical utility of this class is threatened by the emergence of resistances favored by their increasing use related to the emergence of multi resistant enterobacteria. Currently, combination therapies and use of old antibiotics like colistin are frequently the only possibilities.
During the last decade, Acinetobacter baumannii (AB) has been increasingly responsible for infections occurring in three particular contexts (in terms of patients and environment). Community AB pneumonia is severe infections, mainly described around the Indian Ocean, and which mainly concern patients with major co-morbidities. AB is also responsible for infections occurring among soldiers wounded in action during operations conducted in Iraq or Afghanistan. Lastly, this bacterium is responsible for infections occurring among casualties from natural disasters like earthquakes and tsunamis. Those infections are often due to multidrug-resistant strains, which can be implicated in nosocomial outbreaks when patients are hospitalized in a local casualty department or during their repatriation thereafter. The source of the contaminations which lead to AB infections following injuries (warfare or natural disasters) is still poorly known. Three hypotheses are usually considered: a contamination of wounds with environmental bacteria, a wound contamination from a previous cutaneous or oropharyngeal endogenous reservoir, or hospital acquisition. The implication of telluric or agricultural primary reservoirs in human AB infections is a common hypothesis which remains to be demonstrated by further specifically designed studies.
Background
Prolonged life expectancy has currently increased the proportion of the very elderly among patients with community-acquired pneumonia (CAP). The aim of this study was to determine the influence of age and comorbidity on microbial patterns in patients over 65 years of age with CAP.
Methods
This study was a prospective observational study of adult patients with CAP (excluding those in nursing homes) over a 12-year period. We compared patients aged 65 to 74 years, 75 to 84 years, and > 85 years for potential differences in clinical presentation, comorbidities, severity on admission, microbial investigations, causes, antimicrobial treatment, and outcomes.
Results
We studied a total of 2,149 patients: 759 patients (35.3%) aged 65 to 74 years, 941 patients (43.7%) aged 75 to 84 years, and 449 patients (20.8%) aged > 85 years. At least one comorbidity was present in 1,710 patients (79.6%). Streptococcus pneumoniae was the most frequent pathogen in all age groups, regardless of comorbidity. Staphylococcus aureus, Enterobacteriaceae, and Pseudomonas aeruginosa accounted for 9.1% of isolates, and Haemophilus influenzae, 6.4%. All these pathogens were isolated only in patients with at least one comorbidity. Mortality increased with age (65-74 years, 6.9%; 75-84 years, 8.9%; > 85 years, 17.1%; P < .001) and was associated with increased comorbidities (neurologic; OR, 2.1; 95% CI, 1.5-2.1), Pneumonia Severity Index IV or V (OR, 3.2; 95% CI, 1.8-6.0), bacteremia (OR, 1.7; 95% CI, 1.1-2.7), the presence of a potential multidrug-resistant (MDR) pathogen (S aureus, P aeruginosa, Enterobacteriaceae; OR, 2.4; 95% CI, 1.3-4.3), and ICU admission (OR, 4.2; 95% CI, 2.9-6.1) on multivariate analysis.
Conclusions
Age does not influence microbial cause itself, whereas comorbidities are associated with specific causes such as H influenzae and potential MDR pathogens. Mortality in the elderly is mainly driven by the presence of comorbidities and potential MDR pathogens.
Community-acquired pneumonia remains a common illness with substantial morbidity and mortality. Current management challenges focus on identifying the likely etiologic pathogens based on an assessment of host risk factors, while attempting to make a specific etiologic diagnosis, which is often not possible. Therapy is necessarily empiric and focuses on pneumococcus and atypical pathogens for all patients, with consideration of other pathogens based on specific patient risk factors. It is important to understand the expected response to effective therapy, and to identify and manage clinical failure at the earliest possible time point. Prevention is focused on smoking cessation and vaccination against pneumococcus and influenza.
Antimicrobial resistance is a global problem and the prevalence is high in many Asian countries.
A prospective observational study of the prevalence of bacterial pathogens and their antimicrobial susceptibilities in patients with acute exacerbations of chronic bronchitis (AECB) was conducted in Indonesia, Philippines, Korea, Thailand, Malaysia, Taiwan and Hong Kong from August 2006 to April 2008. The diagnosis of AECB was based on increased cough and worsening of two of following: dyspnoea, increased sputum volume or purulence. Patients who had taken antibiotics within 72 h of presentation were excluded. All bacterial strains were submitted to a central laboratory for re-identification and antimicrobial susceptibility testing to 16 antimicrobial agents according to Clinical and Laboratory Standards Institute.
Four hundred and seven isolates were identified among 447 patients of AECB. The most frequent organisms isolated were Klebsiella pneumoniae and associated species (n = 91 + 17), Haemophilus influenzae (n = 71), Pseudomonas aeruginosa (n = 63), Streptococcus pneumoniae (n = 32), Acinetobacter baumannii (n = 22) and Moraxella catarrhalis (n = 21). According to Clinical and Laboratory Standards Institute susceptibility breakpoints, 85.7% and >90% of these pathogens were susceptible to levofloxacin and cefepime respectively. Other options with overall lower susceptibilities include imipenem, ceftazidime, ceftriaxone and amoxicillin/clavulanate.
Gram-negative bacteria including Klebsiella spp., P. aeruginosa and Acinetobacter spp. constitute a large proportion of pathogens identified in patients with AECB in some Asian countries. Surveillance on the local prevalence and antibiotic resistance of these organisms is important in guiding appropriate choice of antimicrobials in the management of AECB.
Many studies have evaluated the clinical characteristics of Gram-negative bacteria (GNB) pneumonia. However, in most cases the bacteriological diagnosis is based on unreliable respiratory samples, and research rarely focuses on only bacteraemic patients. The aim of this study was to describe the incidence, clinical characteristics, outcomes, and factors associated with severity during the hospital stay of patients diagnosed with bacteraemic community-acquired pneumonia (CAP) due to GNB.
Patients consecutively admitted with bacteraemic CAP due to GNB were enrolled in the study, with exclusion of additional foci of infection.
CAP due to GNB accounted for 1.2% of the total CAP cases admitted and 3.5% of those with a confirmed aetiological diagnosis. Fifty-one patients were studied (mean age: 73 ± 11.3 years). Escherichia coli (30 cases; 58.8%) and Klebsiella pneumoniae (9 cases; 17.6%) were the most commonly isolated strains. The main symptoms were fever, cough, and dyspnoea. Eleven (21.6%) patients presented mental confusion, ten (19.6%) followed a severe clinical course, and six (11.8%) died. Absence of fever, radiologically multilobar involvement, and the prescription of an inadequate empirical antimicrobial therapy were independent factors associated with severity during the hospital stay.
Bacteraemic CAP due to GNB is an uncommon entity. Among the patients studied, E. coli was the main GNB found. A total of 19.6% of patients followed a severe clinical course. The factors identified in this study may alert physicians to a group of patients at risk of suffering complications during their hospital stay.
We describe a case of fulminant community-acquired pneumonia probably caused by Acinetobacter lwoffii. A 63-year-old woman was admitted with an acute respiratory illness and consolidation in the right upper lobe. She deteriorated rapidly despite antibiotic therapy, and required ventilatory support. The patient died of multiple organ failure and intractable shock, 7 days after admission to hospital; her disease was probably caused by A. lwoffii.
Patients with community-acquired Acinetobacter baumannii (AB) pneumonia have been reported from subtropical countries. We investigated the epidemiology, clinical and microbiological characteristics of community-acquired pneumonia (CAP) due to AB in Singapore.
A retrospective case series was performed over a 21-month period at two institutions.
From 1 January 2007 to 30 September 2008, eight patients were diagnosed with CAP due to AB. Seven had bacteraemia and five were sputum culture-positive. The median age at presentation was 58.5 years (range 45-76 years). Five patients (71.4%) acquired the pneumonia in the warmer months of June to September. Presentation was acute, with a median duration of 2.5 days (range 1-7 days). The median Acute Physiology and Chronic Health Evaluation II score was 28.5 (range 6-36). Six patients presented with septic shock, lactic acidosis, acute kidney injury and respiratory failure, necessitating ICU care; five of these patients eventually died. All patients received empirical antibiotics, including third-generation cephalosporins, which were inactive against the organism. All isolates were susceptible to ampicillin/sulbactam, ciprofloxacin, co-trimoxazole, aminoglycosides and imipenem.
Community-acquired AB pneumonia have a fulminant course. In a region endemic for melioidosis and severe community-acquired Klebsiella pneumoniae, the challenge lies in rapid identification and initiation of appropriate empirical antibiotics to improve the survival of patients with AB CAP.
Over a period of 4 consecutive yr, 92 nonimmunosuppressed patients (21 women and 71 men aged 53 +/- 16 yr, means = SD) with critical acute respiratory failure (PaO2/FiO2, 209 +/- 9 mm Hg) caused by severe community-acquired pneumonia were admitted to the respiratory intensive care unit (RICU) of a general hospital. The most frequent underlying clinical condition was chronic obstructive pulmonary disease (44 patients, 48%). A total of 56 patients (61%) required mechanical ventilation for a mean period of 10.7 +/- 12.5 days, 29 of them (52%) needing PEEP (9.9 +/- 3.8 cm H2O). A group of 23 (25%) patients had criteria of adult respiratory distress syndrome (ARDS). A causal microorganism was identified in 48 patients (52%), the two most frequent etiologies being Streptococcus pneumoniae (14, 15%) and Legionella pneumophila (13, 14%). Pseudomonas aeruginosa (5, 5%) was always associated with bronchiectasis. Mortality due to severe community-acquired pneumonia was 22% (20 patients). According to univariate analysis, mortality was associated with anticipated death within 4 to 5 yr, inadequate antibiotic treatment before RICU admission, mechanical ventilation requirements, use of PEEP, FIO2 greater than 0.6, coexistence of ARDS, radiographic spread of the pneumonia during RICU admission, septic shock, bacteremia, and P. aeruginosa as the cause of the pneumonia. Further, recursive partitioning analysis selected two factors significantly related to the prognosis: the radiographic spread of the pneumonia during RICU admission and the presence of septic shock.(ABSTRACT TRUNCATED AT 250 WORDS)
The aim of this study was to determine the etiology of community-acquired pneumonia (CAP) and the impact of age, comorbidity, and severity on microbial etiologies of such pneumonia. Overall, 395 consecutive patients with CAP were studied prospectively during a 15-mo period. Regular microbial investigation included examination of sputum, blood culture, and serology. Sampling of pleural fluid, transthoracic puncture, tracheobronchial aspiration, and protected specimen brush (PSB) sampling were performed in selected patients. The microbial etiology was determined in 182 of 395 (46%) cases, and 227 pathogens were detected. The five most frequent pathogens were Streptococcus pneumoniae (65 patients [29%]), Haemophilus influenzae (25 patients [11%]), Influenza virus A and B (23 patients [10%]), Legionella sp. (17 patients [8%]), and Chlamydia pneumoniae (15 patients [7%]). Gram-negative enteric bacilli (GNEB) accounted for 13 cases (6%) and Pseudomonas aeruginosa for 12 cases of pneumonia (5%). Patients aged < 60 yr were at risk for an "atypical" bacterial etiology (odds ratio [OR]: 2.3; 95% confidence interval [CI]: 1.2 to 4.5), especially Mycoplasma pneumoniae (OR: 5.3; 95% CI: 1.7 to 16.8). Comorbid pulmonary, hepatic, and central nervous illnesses, as well as current cigarette smoking and alcohol abuse, were all associated with distinct etiologic patterns. Pneumonia requiring admission to the intensive care unit was independently associated with the pathogens S. pneumoniae (OR: 2.5; 95% CI: 1.3 to 4.7), gram-negative enteric bacilli, and P. aeruginosa (OR: 2.5; 95% CI: 0.99 to 6.5). Clinical and radiographic features of "typical" pneumonia were neither sensitive nor specific for the differentiation of pneumococcal and nonpneumococcal etiologies. These results support a management approach based on the associations between etiology and age, comorbidity, and severity, instead of the traditional syndromic approach to CAP.
To survey the etiology and epidemiology of community-acquired pneumonia (CAP) in relation to age, comorbidity, and severity and to investigate prognostic factors.
Prospective epidemiologic study, single center.
University hospital at Buenos Aires, Argentina.
Outpatients and inpatients fulfilling clinical criteria of CAP.
Systematic laboratory evaluation for determining the etiology, and clinical evaluation stratifying patients into mild, moderate, and severe CAP (groups 1 to 3), a clinical rule used for hospitalization.
During a 12-month period, 343 patients (mean age, 64.4 years; range, 18 to 102 years) were evaluated. We found 167 microorganisms in 144 cases (yield, 42%). Streptococcus pneumoniae, the most common pathogen, was isolated in 35 cases (24%). Mycoplasma pneumoniae, present in 19 (13%), was second in frequency in group 1; Haemophilus influenzae, present in 17 cases (12%), was second in group 2; and Chlamydia pneumoniae, present in 12 cases (8%), was second in group 3. Etiology could not be determined on the basis of clinical presentation; identifying the etiology had no impact on mortality. Some findings were associated with specific causative organisms and outcome. A significantly lower number of nonsurvivors received adequate therapy (50% vs 77%).
Age, comorbidities, alcohol abuse, and smoking were related with distinct etiologies. PaO(2) to fraction of inspired oxygen ratio < 250, aerobic Gram-negative pathogen, chronic renal failure, Glasgow score < 15, malignant neoplasm, and aspirative pneumonia were associated with mortality by multivariate analysis. Local microbiologic data could be of help in tailoring therapeutic guidelines to the microbiologic reality at different settings. The stratification schema and the clinical rule used for hospitalization were useful.
All patients with severe pneumonias (community-acquired and nosocomial) who required treatment in the intensive care unit (ICU) were included in a 3-year prospective study. Predictive factors for a fatal outcome were analyzed in 127 patients. An etiologic diagnosis was made in 70 (55.1%) patients. Culture of sputum or tracheobronchial secretions were used only as criteria for microbiologic diagnosis of Legionella pneumophila. The pathogens most frequently identified were L pneumophila, Streptococcus pneumoniae, and Pseudomonas aeruginosa. Viruses were not detected as causative agents. A total of 54 patients died (mortality rate, 42.5%). The univariate analysis showed the following factors associated with mortality: advanced age (≥70 years); presence of septic shock, requirement of mechanical ventilation, and Simplified Acute Physiology Score [SAPS] index >12 at the time of admission to the ICU or when symptoms appeared in patients already admitted to the ICU; development of any complication during ICU hospitalization; and P aeruginosa as the etiologic agent of the pneumonia. When all variables were introduced by a stepwise method, the final model included advanced age (≥70 years), SAPS index >12, presence of septic shock, requirement of mechanical ventilation, bilateral pulmonary involvement, and P aeruginosa as the etiologic agent of pneumonia as prognostic factors associated with a fatal outcome.
A prospective study of 132 patients with severe community-acquired pneumonia (CAP) treated in the ICU was carried out to determine the causative agents, the value of the clinical, biological, and radiologic features in predicting the etiology, and to define prognostic factors. The study group included 98 men and 34 women (mean age: 5±18 years). The most frequent underlying condition was COPD (51 patients, 39 percent). On admission, 35 patients were in shock, 71 were mentally confused, and 81 (61 percent) required mechanical ventilation during their hospitalization. The clinical, laboratory, and radiologic parameters were of little value for predicting the etiology in patients with severe CAP. An etiologic diagnosis was made in 95 (72 percent) patients. The most frequent pathogens were Streptococcus pneumoniae (43 cases [45 percent]), Gram-negative bacilli (14 cases [15 percent]), and Haemophilus influenzae (14 cases [15 percent]) Mortality was 24 percent. It was significantly associated with a age more than 60 years, septic shock, impairment of alertness, mechanical ventilation requirement, bacteremic pneumonia, and S pneumoniae or Enterobacteriaceae as the causes of the pneumonia. Recommendations for antibiotic chemotherapy in patients with severe CAP admitted to the ICU are included.
All patients with severe pneumonias (community-acquired and nosocomial) who required treatment in the intensive care unit (ICU) were included in a 3-year prospective study. Predictive factors for a fatal outcome were analyzed in 127 patients. An etiologic diagnosis was made in 70 (55.1%) patients. Culture of sputum or tracheobronchial secretions were used only as criteria for microbiologic diagnosis of Legionella pneumophila. The pathogens most frequently identified were L pneumophila, Streptococcus pneumoniae, and Pseudomonas aeruginosa. Viruses were not detected as causative agents. A total of 54 patients died (mortality rate, 42.5%). The univariate analysis showed the following factors associated with mortality: advanced age (> or = 70 years); presence of septic shock, requirement of mechanical ventilation, and Simplified Acute Physiology Score [SAPS] index > 12 at the time of admission to the ICU or when symptoms appeared in patients already admitted to the ICU; development of any complication during ICU hospitalization; and P aeruginosa as the etiologic agent of the pneumonia. When all variables were introduced by a stepwise method, the final model included advanced age (> or = 70 years), SAPS index > 12, presence of septic shock, requirement of mechanical ventilation, bilateral pulmonary involvement, and P aeruginosa as the etiologic agent of pneumonia as prognostic factors associated with a fatal outcome.
A prospective study of 132 patients with severe community-acquired pneumonia (CAP) treated in the ICU was carried out to determine the causative agents, the value of the clinical, biological, and radiologic features in predicting the etiology, and to define prognostic factors. The study group included 98 men and 34 women (mean age: 58 +/- 18 years). The most frequent underlying condition was COPD (51 patients, 39 percent). On admission, 35 patients were in shock, 71 were mentally confused, and 81 (61 percent) required mechanical ventilation during their hospitalization. The clinical, laboratory, and radiologic parameters were of little value for predicting the etiology in patients with severe CAP. An etiologic diagnosis was made in 95 (72 percent) patients. The most frequent pathogens were Streptococcus pneumoniae (43 cases [45 percent]), Gram-negative bacilli (14 cases [15 percent]), and Haemophilus influenzae (14 cases [15 percent]) Mortality was 24 percent. It was significantly associated with a age more than 60 years, septic shock, impairment of alertness, mechanical ventilation requirement, bacteremic pneumonia, and S pneumoniae or Enterobacteriaceae as the causes of the pneumonia. Recommendations for antibiotic chemotherapy in patients with severe CAP admitted to the ICU are included.
There is considerable variability in rates of hospitalization of patients with community-acquired pneumonia, in part because of physicians' uncertainty in assessing the severity of illness at presentation.
From our analysis of data on 14,199 adult inpatients with community-acquired pneumonia, we derived a prediction rule that stratifies patients into five classes with respect to the risk of death within 30 days. The rule was validated with 1991 data on 38,039 inpatients and with data on 2287 inpatients and outpatients in the Pneumonia Patient Outcomes Research Team (PORT) cohort study. The prediction rule assigns points based on age and the presence of coexisting disease, abnormal physical findings (such as a respiratory rate of > or = 30 or a temperature of > or = 40 degrees C), and abnormal laboratory findings (such as a pH <7.35, a blood urea nitrogen concentration > or = 30 mg per deciliter [11 mmol per liter] or a sodium concentration <130 mmol per liter) at presentation.
There were no significant differences in mortality in each of the five risk classes among the three cohorts. Mortality ranged from 0.1 to 0.4 percent for class I patients (P=0.22), from 0.6 to 0.7 percent for class II (P=0.67), and from 0.9 to 2.8 percent for class III (P=0.12). Among the 1575 patients in the three lowest risk classes in the Pneumonia PORT cohort, there were only seven deaths, of which only four were pneumonia-related. The risk class was significantly associated with the risk of subsequent hospitalization among those treated as outpatients and with the use of intensive care and the number of days in the hospital among inpatients.
The prediction rule we describe accurately identifies the patients with community-acquired pneumonia who are at low risk for death and other adverse outcomes. This prediction rule may help physicians make more rational decisions about hospitalization for patients with pneumonia.
This is part of the series of practice guidelines commissioned by the Infectious Diseases Society of America through its Practice Guidelines Committee. The purpose of this guideline is to provide assistance to clinicians in the diagnosis and treatment of community-acquired pneumonia. The targeted providers are internists and family practitioners. The targeted groups are immunocompetent adult patients. Criteria are specified for determining whether the inpatient or outpatient setting is appropriate for treatment. Differences from other guidelines written on this topic include use of laboratory criteria for diagnosis and approach to antimicrobial therapy. Panel members and consultants are experts in adult infectious diseases. The guidelines are evidence based where possible. A standard ranking system is used for the strength of the recommendations and the quality of the evidence cited in the literature reviewed. The document has been subjected to external review by peer reviewers as well as by the Practice Guidelines Committee and was approved by the IDSA Council. An executive summary and tables highlight the major recommendations. The guidelines will be listed on the IDSA home page at http://www.idsociety.org.
In this prospective study, the authors assessed the incidence, aetiology, and outcome of patients with community-acquired pneumonia in the general population. From December 1993 to November 1995, a study was performed in a mixed residential-industrial urban population of the "Maresme" region in Barcelona, Spain. All subjects > or =14 yrs of age (annual average population size 74,368 inhabitants) with clinically suspected community-acquired pneumonia were registered. All cases were re-evaluated by chest radiographs on the 5th day of illness and at monthly intervals until complete recovery. Urine and blood samples were obtained for culture and antigen detection. When lower respiratory tract secretions were obtained, these were also cultured. There were 241 patients with community-acquired pneumonia, with an annual incidence rate of 1.62 cases (95% confidence interval, 1.42-1.82) per 1,000 inhabitants. Incidence rates increased by age groups and were higher in males than in females. Of 232 patients with aetiological data, 104 had an identifiable aetiology. A total of 114 pathogens were found (single pathogen 94, two pathogens 10). There were 81 episodes of bacterial infection and 33 of viral infection. The most common pathogens were Streptococcus pneumoniae, Chlamydia pneumoniae, and influenza A and B viruses. No case of Hantavirus infection was found. The rate of hospital admission was 61.4% with a mean+/-SD length of 11.7+/-10.1 days, a mean period of 23.0+/-14.3 days inactivity, and an overall mortality rate of 5%. The high rate of hospital admission, prolonged stay in hospital, and long period of inactivity all continue to constitute a social and health care burden of community-acquired pneumonia.
Inadequate antimicrobial treatment, generally defined as microbiological documentation of an infection that is not being effectively
treated, is an important factor in the emergence of infections due to antibiotic-resistant bacteria. Factors that contribute
to inadequate antimicrobial treatment of hospitalized patients include prior antibiotic exposure, use of broad-spectrum antibiotics,
prolonged length of stay, prolonged mechanical ventilation, and presence of invasive devices. Strategies to minimize inadequate
treatment include consulting an infectious disease specialist, using antibiotic practice guidelines, and identifying quicker
methods of microbiological identification. In addition, clinicians should determine the prevailing pathogens that account
for the community-acquired and nosocomial infections identified in their hospitals. Clinicians can improve antimicrobial treatment
by using empirical combination antibiotic therapy based on individual patient characteristics and the predominant bacterial
flora and their antibiotic susceptibility profiles. This broad-spectrum therapy can then be narrowed when initial culture
results are received. Further study evaluating the use of antibiotic practice guidelines and strategies to reduce inadequate
treatment is necessary to determine their impact on patient outcomes.
To study the validity of a recently developed community-acquired pneumonia (CAP) severity prediction rule in estimating mortality, to determine its utility in decision making regarding hospitalization, and to assess factors influencing this decision.
Retrospective chart review.
Two sites of the University Health Network, the Toronto General and Toronto Western Hospitals, tertiary-care teaching institutions with a sizable primary-care and secondary-care source of referrals, and a total of 900 beds.
Consecutive patients with CAP admitted between February and June 1996. Measurements and results: A single trained medical records extractor assembled data to compare our population to that used in developing the CAP prediction rule, in terms of mortality and to assess reasons for hospitalization. Two hundred fifty-five eligible patients were admitted, and 244 charts (96%) were available. Our patients tended to be older, with nearly four times as many residents of chronic care institutions (39% compared with 10%), and had a higher risk class distribution than the published cohort. Risk class-specific mortality was similar in four of five classes. Of the 71 patients in the low-risk classes, 67 had additional reasons for admission; 18 of which were psychosocial (homelessness, substance abuse, or inadequate home supports).
The CAP severity prediction rule estimates mortality well. Admission of low-risk patients was linked to psychosocial and other medical reasons not captured by this rule. The rule can be very useful in assessing the need for hospitalization; however, there remains a significant percentage of patients with a low severity score who may require hospitalization for psychosocial and economic considerations.
Initial empirical antimicrobial treatment of patients with community-acquired pneumonia (CAP) is based on expected microbial patterns. We determined the incidence of, prognosis of, and risk factors for CAP due to gram-negative bacteria (GNB), including Pseudomonas aeruginosa.
Consecutive patients with CAP hospitalized in our 1000-bed tertiary care university teaching hospital were studied prospectively. Independent risk factors for CAP due to GNB and for death were identified by means of stepwise logistic regression analysis.
From January 1, 1997, until December 31, 1998, 559 hospitalized patients with CAP were included. Sixty patients (11%) had CAP due to GNB, including P aeruginosa in 39 (65%). Probable aspiration (odds ratio [OR], 2.3; 95% confidence interval [CI], 1.02-5.2; P =.04), previous hospital admission (OR, 3.5; 95% CI, 1.7-7.1; P<.001), previous antimicrobial treatment (OR, 1.9; 95% CI, 1.01-3.7; P =.049), and the presence of pulmonary comorbidity (OR, 2.8; 95% CI, 1.5-5.5; P =.02) were independent predictors of GNB. In a subgroup analysis of P aeruginosa pneumonia, pulmonary comorbidity (OR, 5.8; 95% CI, 2.2-15.3; P<.001) and previous hospital admission (OR, 3.8; 95% CI, 1.8-8.3; P =.02) were predictive. Infection with GNB was independently associated with death (relative risk, 3.4; 95% CI, 1.6-7.4; P =.002).
In our setting, in every tenth patient with CAP, an etiology due to GNB has to be considered. Patients with probable aspiration, previous hospitalization or antimicrobial treatment, and pulmonary comorbidity are especially prone to GNB. These pathogens are also an independent risk factor for death in patients with CAP.
The objectives were to characterize the prognostic factors and evaluate the impact of inappropriate empiric antibiotic treatment and systemic response on the outcome of critically ill patients with community-acquired bloodstream infection (BSI).
A prospective, multicenter, observational study was carried out in 339 patients admitted in 30 ICUs for BSI.
Crude mortality was 41.5%. Septic shock was present in 184 patients (55%). The pathogens most frequently associated with septic shock or death were Escherichia coli, Staphylococcus aureus, and Streptococcus pneumoniae, which accounted for approximately half of the deaths. Antibiotic treatment was found to be inappropriate in 14.5% of episodes. Patients in septic shock with inappropriate treatment had a survival rate below 20%. Multivariate analysis identified a significant association between septic shock and four variables: age > or = 60 years (odds ratio [OR], 1.96), previous corticosteroid therapy (OR, 2.58), leukopenia (OR, 2.32), and BSI secondary to intra-abdominal (OR, 2.38) and genitourinary tract (OR, 2.29) infections. The variables that independently predicted death at ICU admission were APACHE (acute physiology and chronic health evaluation) II score > or = 15 (OR, 2.42), development of septic shock (OR, 3.22), and inappropriate empiric antibiotic treatment (OR, 4.11). This last variable was independently associated with an unknown source of sepsis (OR, 2.49). Mortality attributable to inappropriate antibiotic treatment increased with the severity of illness at ICU admission (10.7% for APACHE II score < 15 and 41.8% for APACHE II score > or = 25, p < 0.01).
Inappropriate antimicrobial treatment is the most important influence on outcome in patients admitted to the ICU for community-acquired BSI, particularly in presence of septic shock or high degrees of severity. Initial broad-spectrum therapy should be prescribed to septic patients in whom the source is unknown or in those requiring vasopressors.
Severe community-acquired pneumonia (CAP) is a life-threatening condition that requires intensive care unit (ICU) admission. Clinical presentation is characterized by the presence of respiratory failure, severe sepsis, or septic shock. Severe CAP accounts for approximately 5–35% of hospital-treated cases of pneumonia with the majority of patients having underlying comorbidities. The most common pathogens associated with this disease are Streptococcus pneumoniae, Legionella spp., Haemophilus influenzae, and Gram-negative enteric rods.
Microbial investigation is probably helpful in the individual case but is likely to be more useful for defining local antimicrobial policies. The early and rapid initiation of empiric antimicrobial treatment is critical for a favorable outcome. It should include intravenous β-lactam along with either a macrolide or a fluoroquinolone. Modifications of this basic regimen should be considered in the presence of distinct comorbid conditions and risk factors for specific pathogens. Other promising nonantimicrobial new therapies are currently being investigated.
The assessment of severity of CAP helps physicians to identify patients who could be managed safely in an ambulatory setting. It may also play a crucial role in decisions about length of hospital stay and time of switching to oral antimicrobial therapy in different groups at risk. The most important adverse prognostic factors include advancing age, male sex, poor health of patient, acute respiratory failure, severe sepsis, septic shock, progressive radiographic course, bacteremia, signs of disease progression within the first 48–72 hours, and the presence of several different pathogens such as S. pneumoniae, Staphylococcus aureus, Gram-negative enteric bacilli, or Pseudomonas aeruginosa. However, some important topics of severity assessment remain controversial, including the definition of severe CAP. Prediction rules for complications or death from CAP, although far from perfect, should identify the majority of patients with severe CAP and be used to support decision-making by the physician. They may also contribute to the evaluation of processes and outcomes of care for patients with CAP.
The aim of this multicenter study was to identify the causative pathogens of community-acquired pneumonia (CAP) in Shanghai, China, and to determine their susceptibility to antimicrobial agents. Pathogens obtained from 389 patients with documented CAP during 2001-2003 were identified by multiple diagnostic tools that included bacterial culture, polymerase chain reaction (PCR), and specific immunological assays. Susceptibility of the bacterial isolates was tested by the broth microdilution method. A specific pathogen was identified in 39.8% (155/389) of the patients: Haemophilus influenzae (n=80), Klebsiella spp. (n=15), Streptococcus pneumoniae (n=12), Staphylococcus aureus (n=6), Moraxella catarrhalis (n=1), other gram-negative organisms (n=9), and atypical pathogens that comprised Mycoplasma pneumoniae (n=42), Chlamydia pneumoniae (n=17), and Legionella pneumophila (n=2). Most H. influenzae isolates were susceptible to ampicillin (88.3%), and all were susceptible to macrolides. Of the S. pneumoniae isolates, 75% (9/12) were susceptible to penicillin, while 25% (3/12) were intermediately susceptible. H. influenzae and atypical pathogens are among the most important pathogens of CAP. Ampicillin, cephalosporins, and the newer fluoroquinolones can be used as empirical therapy for CAP in the Shanghai area. The efficacy of monotherapy with newer macrolides for CAP caused by S. pneumoniae requires further evaluation.
Appropriate antimicrobial treatment of community-acquired pneumonia (CAP) should be based on the distribution of aetiological pathogens, antimicrobial resistance of major pathogens, clinical characteristics and outcomes. We performed a prospective observational study of 955 cases of adult CAP in 14 hospitals in eight Asian countries. Microbiological evaluation to determine etiological pathogens as well as clinical evaluation was performed. Bronchopulmonary disease (29.9%) was the most frequent underlying disease, followed by cardiovascular diseases (19.9%), malignancy (11.7%) and neurological disorder (8.2%). Streptococcus pneumoniae (29.2%) was the most common isolate, followed by Klebsiella pneumoniae (15.4%) and Haemophilus influenzae (15.1%). Serological tests were positive for Mycoplasma pneumoniae (11.0%) and Chlamydia pneumoniae (13.4%). Only 1.1% was positive for Legionella pneumophila by urinary antigen test. Of the pneumococcal isolates, 56.1% were resistant to erythromycin and 52.6% were not susceptible to penicillin. Seventeen percent of CAP had mixed infection, especially S. pneumoniae with C. pneumoniae. The overall mortality rate was 7.3%, and nursing home residence, mechanical ventilation, malignancy, cardiovascular diseases, respiratory rate>30/min and hyponatraemia were significant independent risk factors for mortality by multivariate analysis (P<0.05). The current data provide relevant information about pathogen distribution and antimicrobial resistance of major pathogens of CAP as well as clinical outcomes of illness in Asian countries.