Is healthcare-associated pneumonia a distinct entity needing specific therapy?

Risk of Multidrug-Resistant Pathogens in Severe Community-Acquired Pneumonia

Severe community-acquired pneumonia (SCAP) is difficult to treat when caused by difficult-to-treat (DTR) pathogens because of limited treatment options and poorer clinical outcomes. Over time, several predictive scoring systems based on risk factors for infection with multidrug resistant pathogens have been developed. We reviewed the available tools for identifying DTR pathogens as the cause of SCAP, both predictive scoring systems and rapid diagnostic methods, to develop management strategies aimed at early identification of DTR pathogens, reducing broad-spectrum antibiotic use and improving clinical outcomes. The scoring systems reviewed show considerable heterogeneity among them at the level of the region studied, the definition of risk factors, as well as which DTR pathogens are the target pathogens. The models described have shown limited effectiveness in reducing inappropriate antibiotic treatment or improving patient outcomes by themselves. However, predictive models could serve as a first step in identifying DTR pathogen infections as part of a larger detection algorithm. Rapid diagnostic tools, such as multiplex polymerase chain reaction, would be useful for the rapid identification of pneumonia-causing pathogens and their resistance mechanisms. In resource-limited settings, rapid tests should be limited to patients at high risk of developing SCAP due to DTR pathogens. We propose an integrative algorithm based on the different scores, taking into account local epidemiological data, where ideally each center should have an antimicrobial stewardship program.

Hospital-acquired and ventilator-associated pneumonia caused by multidrug-resistant Gram-negative pathogens: Understanding epidemiology, resistance patterns, and implications with COVID-19

The ongoing spread of antimicrobial resistance has complicated the treatment of bacterial hospital-acquired pneumonia (HAP) and ventilator-associated pneumonia (VAP). Gram-negative pathogens, especially those with multidrug-resistant profiles, including Escherichia coli, Klebsiella pneumoniae, Enterobacter spp., Pseudomonas aeruginosa, and Acinetobacter spp., are important culprits in this type of infections. Understanding the determinants of resistance in pathogens causing pneumonia is ultimately stressing, especially in the shadows of the COVID-19 pandemic, when bacterial lung infections are considered a top priority that has become urgent to revise. Globally, the increasing prevalence of these pathogens in respiratory samples represents a significant infection challenge, with major limitations of treatment options and poor clinical outcomes. This review will focus on the epidemiology of HAP and VAP and will present the roles and the antimicrobial resistance patterns of implicated multidrug-resistant (MDR) Gram-negative pathogens like carbapenem-resistant Acinetobacter baumannii (CRAB), carbapenem-resistant Pseudomonas aeruginosa (CRPA), carbapenem-resistant Enterobacterales (CRE), as well as colistin-resistant Gram-negative pathogens and extended-spectrum β-lactamase (ESBL)-producing Enterobacterales. While emerging from the COVID-19 pandemic, perspectives and conclusions are drawn from findings of HAP and VAP caused by MDR Gram-negative bacteria in patients with COVID-19.

Evaluating a novel swallowing assessment as a predictor of mortality and recurring pneumonia in elderly patients with pneumonia

BACKGROUND

Assessment of swallowing functions in elderly people with pneumonia is important. Videofluoroscopic and videoendoscopic examinations have been known as reliable assessments of swallowing functions. However, it is often difficult to use these tools in patients with pneumonia due to their poor condition and/or inadequate hospital facilities. We have previously constructed the Assessment of Swallowing Ability for Pneumonia (ASAP) as a straightforward evaluation for swallowing function. This study investigates the efficacy of the ASAP in predicting several outcomes in elderly patients with pneumonia.

METHODS

Elderly patients with pneumonia (n = 130) who were admitted to Tobata Kyoritsu Hospital from January to June 2016 were enrolled prospectively. Associations between their ASAP scores and in-hospital mortality, recurrence of pneumonia within 30 days, 6-month mortality, and detection of antibiotic-resistant bacteria were evaluated.

RESULTS

Lower ASAP scores were associated with higher rates of in-hospital mortality, recurrence of pneumonia, and 6-month mortality. The areas under the curve were 0.84 (95% confidence interval [CI], 0.72-0.96) for in-hospital mortality, 0.76 (95% CI, 0.67-0.85) for recurrence of pneumonia, 0.74 (95% CI, 0.64-0.84) for 6-month mortality, and 0.67 (95% CI, 0.52-0.82) for detection of antibiotic-resistant bacteria. Multivariate analysis showed that a lower ASAP score was an independent risk factor for in-hospital mortality, recurrence of pneumonia, and 6-month mortality.

CONCLUSIONS

The ASAP was useful for predicting short- and long-term mortalities and recurrence of pneumonia.

Incidence of Antibiotic Treatment Failure in Patients with Nursing Home-Acquired Pneumonia and Community Acquired Pneumonia

Purpose: Nursing home-acquired pneumonia (NHAP) patients are at higher risk of multi-drug resistant infection (MDR) than those with community-acquired pneumonia (CAP). Recent evidence suggests a single risk factor for MDR does not accurately predict the need for broad-spectrum antibiotics. The goal of this study was to compare the rate antibiotic failure between NHAP and CAP patients. Methods: Demographic characteristics, co-morbidities, clinical and laboratory variables, antibiotic therapy, and mortality data were collected retrospectively for all patients with pneumonia admitted to an Internal Medicine Service between April 2017 and April 2018. Results: In total, 313 of 556 patients had CAP and 243 had NHAP. NHAP patients were older, and were more likely to be dependent, to have recent antibiotic use, and to experience treatment failure (odds ratio (OR) 1.583; 95% CI 1.102–2.276; p = 0.013). In multivariate analysis, patient’s origin did not predict treatment failure (OR 1.083; 95% CI 0.726–1.616; p = 0.696). Discussion: Higher rates of antibiotic failure and mortality in NHAP patients were explained by the presence of other risk factors such as comorbidities, more severe presentation, and age. Admission from a nursing home is not a sufficient condition to start broader-spectrum antibiotics.

Health Care-Associated Pneumonia: Is It Still a Useful Concept?

"Health care-associated pneumonia (HCAP) was introduced into guidelines because of concerns about the increasing prevalence of drug-resistant pathogens (DRPs) not covered by standard empirical therapy. We now know that DRPs are very localized phenomena with low rates in most sites. Although HCAP risk factors are associated with a higher mortality, this is driven by comorbidities rather than the pathogens. Empirical coverage of DRPs has generally not resulted in better patient outcomes. A far more nuanced approach must be taken for patients with risk factors for DRPs taking into account the local cause and severity of disease.

Impact of additional antibiotics on in-hospital mortality in tuberculosis isolated general bacteria: A propensity score analysis

Whether or not additional antibiotics with anti-tuberculosis agents are required to treat bacterial co-infection with pulmonary tuberculosis is unclear. We aimed to assess the impact of additional antibiotics on mortality in pulmonary tuberculosis patients whose sputum cultures were positive for general bacteria as a surrogate definition of bacterial pneumonia. This study was a single-center retrospective cohort using a propensity score analysis. We included patients who were admitted for pulmonary tuberculosis and whose sputum cultures were positive for general bacteria. The mortality of patients who received additional antibiotics was analyzed after adjusting for other variables, including the propensity score predicting treatment with additional antibiotics. We assessed 68 and 55 tuberculosis patients treated with and without general antibiotics, respectively. Additional antibiotics tended to be administered to patients with a high level of C-reactive protein and neutrophil count, poor performance status, hypoxemia and hypoalbuminemia (C-statistics of area under receiver operating characteristic curve to the propensity score; 0.884, p < 0.001). In the multivariate analysis, advanced age and not the use of additional antibiotics was associated with in-hospital mortality. Additional antibiotics with anti-tuberculosis agents may not improve the prognosis of pulmonary tuberculosis patients whose sputum cultures were positive for general bacteria. Isolation of general bacteria does not equate to complication with bacterial pneumonia, so physicians should not administer general antibiotics to TB patients based solely on the results of sputum culture for general bacteria. A prospective study is needed to verify these results using a more accurate definition of pulmonary tuberculosis complicated with bacterial pneumonia.

Healthcare-associated pneumonia: is there any reason to continue to utilize this label in 2019?

BACKGROUND

There is an ongoing controversy on the role of the healthcare-associated pneumonia (HCAP) label in the treatment of patients with pneumonia.

OBJECTIVE

To provide an update of the literature on patients meeting criteria for HCAP between 2014 and 2018.

SOURCES

The review is based on a systematic literature search using PubMed-Central full-text archive of biomedical and life sciences literature at the U.S. National Institutes of Health's National Library of Medicine (NIH/NLM).

CONTENT

Studies compared clinical characteristics of patients with HCAP and community-acquired pneumonia (CAP). HCAP patients were older and had a higher comorbidity. Mortality rates in HCAP varied from 5% to 33%, but seemed lower than those cited in the initial reports. Criteria behind the HCAP classification differed considerably within populations. Microbial patterns differed in that there was a higher incidence of methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa, and, to a lesser extent, enterobacteriaceae. Definitions and rates of multidrug-resistant (MDR) pneumonia also varied considerably. Broad-spectrum guideline-concordant treatment did not reduce mortality in four observational studies. The HCAP criteria performed poorly as a predictive tool to identify MDR pneumonia or pathogens not covered by treatment for CAP. A new score (Drug Resistance in Pneumonia, DRIP) outperformed HCAP in the prediction of MDR pathogens. Comorbidity and functional status, but not different microbial patterns, seem to account for increased mortality.

IMPLICATIONS

HCAP should no longer be used to identify patients at risk of MDR pathogens. The use of validated predictive scores along with implementation of de-escalation strategies and careful individual assessment of comorbidity and functional status seem superior strategies for clinical management.

Risk Factors and Outcomes for Ineffective Empiric Treatment of Sepsis Caused by Gram-Negative Pathogens: Stratification by Onset of Infection

Sepsis and septic shock remain serious consequences of infections, with reported mortality rates in excess of 40 percent. Timely antibiotic therapy in cases of sepsis and septic shock is recognized as an important determinant of outcome. However, the administration of ineffective empirical treatment (IET) (an initial antibiotic regimen that is not active against the identified pathogen[s] based on in vitro susceptibility testing results) is associated with excess mortality compared to effective empirical treatment (EET). We examined all hospitalized patients at Barnes-Jewish Hospital with a sterile site (blood or pleural, abdominal, cerebrospinal, synovial, and pericardial fluid) culture positive for Gram-negative (GN) bacteria combined with a primary or secondary ICD-9-CM code for severe sepsis (995.92) or septic shock (785.52) between January 2010 and October 2015. Variables significantly associated with early-onset (<48 h of hospitalization) IET of GN sterile site sepsis and septic shock included age, recent hospitalization, and prior intravenous antibiotics. Late-onset IET was associated with increasing numbers of hospitalization days before infection onset and prior intravenous antibiotic administration. For patients with early-onset infection, we found no difference in rates of survival between patients receiving IET and EET. However, patients in the late-onset infection group receiving IET had a statistically lower rate of survival than those receiving EET. These data suggest that risk factors and outcomes for IET can vary based on the time of onset of infection. Our results also highlight the importance of prior intravenous antibiotic exposure as a risk factor for IET in infections by GN bacteria regardless of the time of onset of infection.

Empiric Antibiotic Therapy of Nosocomial Bacterial Infections

Broad-spectrum antibiotics are commonly used by physicians to treat various infections. The source of infection and causative organisms are not always apparent during the initial evaluation of the patient, and antibiotics are often given empirically to patients with suspected sepsis. Fear of attempting cephalosporins and carbapenems in penicillin-allergic septic patients may result in significant decrease in the spectrum of antimicrobial coverage. Empiric antibiotic therapy should sufficiently cover all the suspected pathogens, guided by the bacteriologic susceptibilities of the medical center. It is important to understand the major pharmacokinetic properties of antibacterial agents for proper use and to minimize the development of resistance. In several septic patients, negative cultures do not exclude active infection and positive cultures may not represent the actual infection. This article will review the important differences in the spectrum of commonly used antibiotics for nosocomial bacterial infections with a particular emphasis on culture-negative sepsis and colonization.

Application of a Risk Score to Identify Older Adults with Community-Onset Pneumonia Most Likely to Benefit From Empiric Pseudomonas Therapy

STUDY OBJECTIVE

To assess the impact of empiric Pseudomonas pharmacotherapy on 30-day mortality in hospitalized patients with community-onset pneumonia stratified according to their risk (low, medium, or high) of drug-resistant pathogens.

DESIGN

Retrospective cohort study.

DATA SOURCE

Veterans Health Administration database.

PATIENTS

A total of 50,119 patients who were at least 65 years of age, hospitalized with pneumonia, and received antibiotics within 48 hours of admission between fiscal years 2002 and 2007. Patients were stratified into empiric Pseudomonas therapy (31,027 patients) and no Pseudomonas therapy (19,092 patients) groups based on antibiotics received during their first 48 hours of admission.

MEASUREMENTS AND MAIN RESULTS

A clinical prediction scoring system developed in 2014 that stratifies patients with community-onset pneumonia according to their risk of drug-resistant pathogens was used to identify patients who were likely to benefit from empiric Pseudomonas therapy as well as those in whom antipseudomonal therapy could be spared; patients were classified into low-risk (68%), medium-risk (21%), and high-risk (11%) groups. Of the 50,119 patients, 62% received Pseudomonas therapy. All-cause 30-day mortality was the primary outcome. Empiric Pseudomonas therapy (adjusted odds ratio 0.72, 95% confidence interval 0.62-0.84) was associated with lower 30-day mortality in the high-risk group but not the low- or medium-risk groups.

CONCLUSION

Application of a risk score for patients with drug-resistant pathogens can identify patients likely to benefit from empiric Pseudomonas therapy. Widespread use of this score could reduce overuse of anti-Pseudomonas antibiotics in low- to medium-risk patients and improve survival in high-risk patients.

Healthcare-associated Pneumonia: Clinical Features and Retrospective Analysis Over 10 Years

Background:

Healthcare-associated pneumonia (HCAP) is associated with drug-resistant pathogens and high mortality, and there is no clear evidence that this is due to inappropriate antibiotic therapy. This study was to elucidate the clinical features, pathogens, therapy, and outcomes of HCAP, and to clarify the risk factors for drug-resistant pathogens and prognosis.

Methods:

Retrospective observational study among hospitalized patients with HCAP over 10 years. The primary outcome was 30-day all-cause hospital mortality after admission. Demographics (age, gender, clinical features, and comorbidities), dates of admission, discharge and/or death, hospitalization costs, microbiological results, chest imaging studies, and CURB-65 were analyzed. Antibiotics, admission to Intensive Care Unit (ICU), mechanical ventilation, and pneumonia prognosis were recorded. Patients were dichotomized based on CURB-65 (low- vs. high-risk).

Results:

Among 612 patients (mean age of 70.7 years), 88.4% had at least one comorbidity. Commonly detected pathogens were Acinetobacter baumannii, Pseudomonas aeruginosa, and coagulase-negative staphylococci. Initial monotherapy with β-lactam antibiotics was the most common initial therapy (50%). Mean age, length of stay, hospitalization expenses, ICU admission, mechanical ventilation use, malignancies, and detection rate for P. aeruginosa, and Staphylococcus aureus were higher in the high-risk group compared with the low-risk group. CURB-65 ≥3, malignancies, and mechanical ventilation were associated with an increased mortality. Logistic regression analysis showed that cerebrovascular diseases and being bedridden were independent risk factors for HCAP.

Conclusion:

Initial treatment of HCAP with broad-spectrum antibiotics could be an appropriate approach. CURB-65 ≥3, malignancies, and mechanical ventilation may result in an increased mortality.

Prognostic implications of aspiration pneumonia in patients with community acquired pneumonia: A systematic review with meta-analysis

Aspiration pneumonia is thought to be associated with a poor outcome in patients with community acquired pneumonia (CAP). However, there has been no systematic review regarding the impact of aspiration pneumonia on the outcomes in patients with CAP. This review was conducted using the MOOSE guidelines: Patients: patients defined CAP. Exposure: aspiration pneumonia defined as pneumonia in patients who have aspiration risk. Comparison: confirmed pneumonia in patients who were not considered to be at high risk for oral aspiration. Outcomes: mortality, hospital readmission or recurrent pneumonia. Three investigators independently identified published cohort studies from PubMed, CENTRAL database, and EMBASE. Nineteen studies were included for this systematic review. Aspiration pneumonia increased in-hospital mortality (relative risk, 3.62; 95% CI, 2.65–4.96; P < 0.001, seven studies) and 30-day mortality (3.57; 2.18–5.86; P < 0.001, five studies). In contrast, aspiration pneumonia was associated with decreased ICU mortality (relative risk, 0.40; 95% CI, 0.26–0.60; P < 0.00001, four studies). Although there are insufficient data to perform a meta-analysis on long-term mortality, recurrent pneumonia, and hospital readmission, the few reported studies suggest that aspiration pneumonia is also associated with these poor outcomes. In conclusion, aspiration pneumonia was associated with both higher in-hospital and 30-day mortality in patients with CAP outside ICU settings.

Risk factors for drug-resistant pathogens in immunocompetent patients with pneumonia: Evaluation of PES pathogens

RATIONALE

The new acronym, PES pathogens (Pseudomonas aeruginosa, Enterobacteriaceae extended-spectrum beta-lactamase-positive, and methicillin-resistant Staphylococcus aureus), was recently proposed to identify drug-resistant pathogens associated with community-acquired pneumonia.

OBJECTIVES

To evaluate the risk factors for antimicrobial-resistant pathogens in immunocompetent patients with pneumonia and to validate the role of PES pathogens.

METHODS

A retrospective analysis of a prospective observational study of immunocompetent patients with pneumonia between March 2009 and June 2015 was conducted. We clarified the risk factors for PES pathogens.

RESULTS

Of the total 1559 patients, an etiological diagnosis was made in 705 (45.2%) patients. PES pathogens were identified in 51 (7.2%) patients, with 53 PES pathogens (P. aeruginosa, 34; ESBL-positive Enterobacteriaceae, 6; and MRSA, 13). Patients with PES pathogens had tendencies toward initial treatment failure, readmission within 30 days, and a prolonged hospital stay. Using multivariate analysis, female sex (adjusted odds ratio [AOR] 1.998, 95% confidence interval [CI] 1.047-3.810), admission within 90 days (AOR 2.827, 95% CI 1.250-6.397), poor performance status (AOR 2.380, 95% CI 1.047-5.413), and enteral feeding (AOR 5.808, 95% CI 1.813-18.613) were independent risk factors for infection with PES pathogens. The area under the receiver operating characteristics curve for the risk factors was 0.66 (95% CI 0.577-0.744).

CONCLUSIONS

We believe the definition of PES pathogens is an appropriate description of drug-resistant pathogens associated with pneumonia in immunocompetent patients. The frequency of PES pathogens is quite low. However, recognition is critical because they can cause refractory pneumonia and different antimicrobial treatment is required.

Expanded CURB-65: a new score system predicts severity of community-acquired pneumonia with superior efficiency

Aim of this study was to develop a new simpler and more effective severity score for community-acquired pneumonia (CAP) patients. A total of 1640 consecutive hospitalized CAP patients in Second Affiliated Hospital of Zhejiang University were included. The effectiveness of different pneumonia severity scores to predict mortality was compared, and the performance of the new score was validated on an external cohort of 1164 patients with pneumonia admitted to a teaching hospital in Italy. Using age ≥ 65 years, LDH > 230 u/L, albumin < 3.5 g/dL, platelet count < 100 × 10⁹/L, confusion, urea > 7 mmol/L, respiratory rate ≥ 30/min, low blood pressure, we assembled a new severity score named as expanded-CURB-65. The 30-day mortality and length of stay were increased along with increased risk score. The AUCs in the prediction of 30-day mortality in the main cohort were 0.826 (95% CI, 0.807–0.844), 0.801 (95% CI, 0.781–0.820), 0.756 (95% CI, 0.735–0.777), 0.793 (95% CI, 0.773–0.813) and 0.759 (95% CI, 0.737–0.779) for the expanded-CURB-65, PSI, CURB-65, SMART-COP and A-DROP, respectively. The performance of this bedside score was confirmed in CAP patients of the validation cohort although calibration was not successful in patients with health care-associated pneumonia (HCAP). The expanded CURB-65 is objective, simpler and more accurate scoring system for evaluation of CAP severity, and the predictive efficiency was better than other score systems.

Current and Future Considerations for the Treatment of Hospital-Acquired Pneumonia

Hospital-acquired pneumonia (HAP) and health-care-associated pneumonia (HCAP) are leading causes of death, morbidity, and resource utilization in hospitalized patients, and are associated with a broad range of Gram-positive and Gram-negative pathogens. Here, we discuss the different definitions of HAP and HCAP, review current guidelines regarding the treatment of these conditions, highlight the shortcomings of current therapeutic options, and discuss new antibiotic treatments. To optimize therapeutic outcomes in patients with HAP/HCAP, initial antimicrobial treatment must be appropriate and should be given as soon as possible; inappropriate or delayed therapy greatly increases morbidity and mortality. Selection of the most appropriate antimicrobial agent depends on the causative pathogen(s); initial broad-spectrum therapy is commonly recommended and should cover all pathogens that may be present. Treatment selection should also take into consideration the following factors: knowledge of underlying local risk factors for antimicrobial resistance, disease staging, and risk factors related to specific pathogens such as Pseudomonas aeruginosa, Acinetobacter spp., and methicillin-resistant Staphylococcus aureus (MRSA). Guidelines consistently emphasize the importance of treating HAP and HCAP with early and appropriate broad-spectrum antibiotics, and recent developments in this field have resulted in the availability of several additional treatment options. Telavancin shows potent activity against Gram-positive bacteria including MRSA and can be administered once daily; it was approved in the USA and European Union for the treatment of HAP after demonstrating non-inferiority to vancomycin. Ceftobiprole medocaril exhibits rapid antimicrobial activity against a broad range of both Gram-positive and Gram-negative pathogens, including MRSA. It was approved for the treatment of HAP (excluding ventilator-associated pneumonia) and community-acquired pneumonia in Europe in 2013. These new treatments may offer effective alternative therapeutic options for the management of HAP.

FUNDING

Basilea Pharmaceutica Ltd., Basel, Switzerland.

Risk factors associated with potentially antibiotic-resistant pathogens in community-acquired pneumonia

RATIONALE

To identify pathogens that require different treatments in community-acquired pneumonia (CAP), we propose an acronym, "PES" (Pseudomonas aeruginosa, Enterobacteriaceae extended-spectrum β-lactamase-positive, and methicillin-resistant Staphylococcus aureus).

OBJECTIVES

To compare the clinical characteristics and outcomes between patients with CAP caused by PES versus other pathogens, and to identify the risk factors associated with infection caused by PES.

METHODS

We conducted an observational prospective study evaluating only immunocompetent patients with CAP and an established etiological diagnosis. We included patients from nursing homes. We computed a score to identify patients at risk of PES pathogens.

MEASUREMENT AND MAIN RESULTS

Of the 4,549 patients evaluated, we analyzed 1,597 who presented an etiological diagnosis. Pneumonia caused by PES was identified in 94 (6%) patients, with 108 PES pathogens isolated (n = 72 P. aeruginosa, n = 15 Enterobacteriaceae extended-spectrum β-lactamase positive, and n = 21 methicillin-resistant Staphylococcus aureus). These patients were older (P = 0.001), had received prior antibiotic treatment more frequently (P < 0.001), and frequently presented with acute renal failure (P = 0.004). PES pathogens were independently associated with increased risk of 30-day mortality (adjusted odds ratio = 2.51; 95% confidence interval = 1.20-5.25; P = 0.015). The area under the curve for the score we computed was 0.759 (95% confidence interval, 0.713-0.806; P < 0.001).

CONCLUSIONS

PES pathogens are responsible for a small proportion of CAP, resulting in high mortality. These pathogens require a different antibiotic treatment, and identification of specific risk factors could help to identify these microbial etiologies.

Antimicrobial de-escalation of treatment for healthcare-associated pneumonia within the Veterans Healthcare Administration

OBJECTIVES

The objective of this study was to measure quantitatively antimicrobial de-escalation utilizing electronic medication administration data based on the spectrum of activity for antimicrobial therapy (i.e. spectrum score) to identify variables associated with de-escalation in a nationwide healthcare system.

METHODS

A retrospective cohort study of patients hospitalized for healthcare-associated pneumonia was conducted in Veterans Affairs Medical Centers (n = 119). Patients hospitalized for healthcare-associated pneumonia on acute-care wards between 5 and 14 days who received antimicrobials for ≥ 3 days during calendar years 2008-11 were evaluated. The spectrum score method was applied at the patient level to measure de-escalation on day 4 of hospitalization. De-escalation was expressed in aggregate and facility-level proportions. Logistic regression was used to assess variables associated with de-escalation. ORs with 95% CIs were reported.

RESULTS

Among 9319 patients, the de-escalation proportion was 28.3% (95% CI 27.4-29.2), which varied 6-fold across facilities [median (IQR) facility-level de-escalation proportion 29.1% (95% CI 21.7-35.6)]. Variables associated with de-escalation included initial broad-spectrum therapy (OR 1.5, 95% CI 1.4-1.5 for each 10% increase in spectrum), collection of respiratory tract cultures (OR 1.1, 95% CI 1.0-1.2) and care in higher complexity facilities (OR 1.3, 95% CI 1.1-1.6). Respiratory tract cultures were collected from 35.3% (95% CI 32.7-37.7) of patients.

CONCLUSIONS

De-escalation of antimicrobial therapy was limited and varied substantially across facilities. De-escalation was associated with respiratory tract culture collection and treatment in a high complexity-level facility.

Application of a methicillin-resistant Staphylococcus aureus risk score for community-onset pneumonia patients and outcomes with initial treatment

BACKGROUND

Community-onset (CO) methicillin-resistant Staphylococcus aureus (MRSA) pneumonia is an evolving problem, and there is a great need for a reliable method to assess MRSA risk at hospital admission. A new MRSA prediction score classifies CO-pneumonia patients into low, medium, and high-risk groups based on objective criteria available at baseline. Our objective was to assess the effect of initial MRSA therapy on mortality in these three risk groups.

METHODS

We conducted a retrospective cohort study using data from the Veterans Health Administration (VHA). Patients were included if they were hospitalized with pneumonia and received antibiotics within the first 48 h of admission. They were stratified into MRSA therapy and no MRSA therapy treatment arms based on antibiotics received in the first 48 h. Multivariable logistic regression was used to adjust for potential confounders.

RESULTS

A total of 80,330 patients met inclusion criteria, of which 36% received MRSA therapy and 64% did not receive MRSA therapy. The majority of patients were classified as either low (51%) or medium (47%) risk, with only 2% classified as high-risk. Multivariable logistic regression analysis demonstrated that initial MRSA therapy was associated with a lower 30-day mortality in the high-risk group (adjusted odds ratio 0.57; 95% confidence interval 0.42-0.77). Initial MRSA therapy was not beneficial in the low or medium-risk groups.

CONCLUSIONS

This study demonstrated improved survival with initial MRSA therapy in high-risk CO-pneumonia patients. The MRSA risk score might help spare MRSA therapy for only those patients who are likely to benefit.

Trends in Antibiotic Use and Nosocomial Pathogens in Hospitalized Veterans With Pneumonia at 128 Medical Centers, 2006-2010

BACKGROUND

In 2005, pneumonia practice guidelines recommended broad-spectrum antibiotics for patients with risk factors for nosocomial pathogens. The impact of these recommendations on the ability of providers to match treatment with nosocomial pathogens is unknown.

METHODS

Among hospitalizations with a principal diagnosis of pneumonia at 128 Department of Veterans Affairs medical centers from 2006 through 2010, we measured annual trends in antibiotic selection; initial blood or respiratory cultures positive for methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa, and Acinetobacter species; and alignment between antibiotic coverage and culture results for MRSA and P. aeruginosa, calculating sensitivity, specificity, and diagnostic odds ratio using a 2 × 2 contingency table.

RESULTS

In 95 511 hospitalizations for pneumonia, initial use of vancomycin increased from 16% in 2006 to 31% in 2010, and piperacillin-tazobactam increased from 16% to 27%, and there was a decrease in both ceftriaxone (from 39% to 33%) and azithromycin (change from 39% to 36%) (P < .001 for all). The proportion of hospitalizations with cultures positive for MRSA decreased (from 2.5% to 2.0%; P < .001); no change was seen for P. aeruginosa (1.9% to 2.0%; P = .14) or Acinetobacter spp. (0.2% to 0.2%; P = .17). For both MRSA and P. aeruginosa, sensitivity increased (from 46% to 65% and 54% to 63%, respectively; P < .001) and specificity decreased (from 85% to 69% and 76% to 68%; P < .001), with no significant changes in diagnostic odds ratio (decreases from 4.6 to 4.1 [P = .57] and 3.7 to 3.2 [P = .95], respectively).

CONCLUSIONS

Between 2006 and 2010, we found a substantial increase in the use of broad-spectrum antibiotics for pneumonia despite no increase in nosocomial pathogens. The ability of providers to accurately match antibiotic coverage to nosocomial pathogens remains low.

Individualizing risk of multidrug-resistant pathogens in community-onset pneumonia

Introduction

The diffusion of multidrug-resistant (MDR) bacteria has created the need to identify risk factors for acquiring resistant pathogens in patients living in the community.

Objective

To analyze clinical features of patients with community-onset pneumonia due to MDR pathogens, to evaluate performance of existing scoring tools and to develop a bedside risk score for an early identification of these patients in the Emergency Department.

Patients and Methods

This was an open, observational, prospective study of consecutive patients with pneumonia, coming from the community, from January 2011 to January 2013. The new score was validated on an external cohort of 929 patients with pneumonia admitted in internal medicine departments participating at a multicenter prospective study in Spain.

Results

A total of 900 patients were included in the study. The final logistic regression model consisted of four variables: 1) one risk factor for HCAP, 2) bilateral pulmonary infiltration, 3) the presence of pleural effusion, and 4) the severity of respiratory impairment calculated by use of PaO2/FiO2 ratio. A new risk score, the ARUC score, was developed; compared to Aliberti, Shorr, and Shindo scores, this point score system has a good discrimination performance (AUC 0.76, 95% CI 0.71-0.82) and calibration (Hosmer-Lemeshow, χ2 = 7.64; p = 0.469). The new score outperformed HCAP definition in predicting etiology due to MDR organism. The performance of this bedside score was confirmed in the validation cohort (AUC 0.68, 95% CI 0.60-0.77).

Conclusion

Physicians working in ED should adopt simple risk scores, like ARUC score, to select the most appropriate antibiotic regimens. This individualized approach may help clinicians to identify those patients who need an empirical broad-spectrum antibiotic therapy.

Detection of pneumonia associated pathogens using a prototype multiplexed pneumonia test in hospitalized patients with severe pneumonia

Severe pneumonia remains an important cause of morbidity and mortality. Polymerase chain reaction (PCR) has been shown to be more sensitive than current standard microbiological methods – particularly in patients with prior antibiotic treatment – and therefore, may improve the accuracy of microbiological diagnosis for hospitalized patients with pneumonia. Conventional detection techniques and multiplex PCR for 14 typical bacterial pneumonia-associated pathogens were performed on respiratory samples collected from adult hospitalized patients enrolled in a prospective multi-center study. Patients were enrolled from March until September 2012. A total of 739 fresh, native samples were eligible for analysis, of which 75 were sputa, 421 aspirates, and 234 bronchial lavages. 276 pathogens were detected by microbiology for which a valid PCR result was generated (positive or negative detection result by Curetis prototype system). Among these, 120 were identified by the prototype assay, 50 pathogens were not detected. Overall performance of the prototype for pathogen identification was 70.6% sensitivity (95% confidence interval (CI) lower bound: 63.3%, upper bound: 76.9%) and 95.2% specificity (95% CI lower bound: 94.6%, upper bound: 95.7%). Based on the study results, device cut-off settings were adjusted for future series production. The overall performance with the settings of the CE series production devices was 78.7% sensitivity (95% CI lower bound: 72.1%) and 96.6% specificity (95% CI lower bound: 96.1%). Time to result was 5.2 hours (median) for the prototype test and 43.5 h for standard-of-care. The Pneumonia Application provides a rapid and moderately sensitive assay for the detection of pneumonia-causing pathogens with minimal hands-on time.

Trial Registration

Deutsches Register Klinischer Studien (DRKS) DRKS00005684

Risk factors for acquiring potentially drug-resistant pathogens in immunocompetent patients with pneumonia developed out of hospital

BACKGROUND

The concept of healthcare-associated pneumonia (HCAP) exists to identify patients infected with highly resistant pathogens who are exposed to the healthcare environment. However, many studies have included immunosuppressed patients who were excluded from the original concept.

OBJECTIVES

The risk factors of potentially drug-resistant (PDR) pathogens in patients with pneumonia developed outside the hospital were reevaluated after excluding the patients who had immunosuppression.

METHODS

This was a retrospective study of prospectively collected data from all consecutive patients with pneumonia who were admitted to hospital via the emergency department between January 2008 and December 2011.

RESULTS

Pathogens were isolated in a total of 315 patients with pneumonia from our cohort; 33% with PDR pathogens did not meet the criteria for HCAP, but 44% without PDR pathogens did meet the criteria. Variables independently associated with PDR included nursing home residency, hospitalization in the preceding 90 days, antibiotics in the 30 days prior to pneumonia, poor function status and chronic lung disease. The new predictive scoring system based on the logistic regression model had a higher predictive power for the risk of PDR pathogens than the presence of the risk factors or the HCAP criteria.

CONCLUSIONS

Functional status, pulmonary comorbidity and previous exposure to the healthcare environment were significantly associated with acquiring PDR pathogens in immunocompetent patients with pneumonia that developed out of hospital. However, a risk stratification model was more accurate than the presence of the risk factors or the HCAP criteria for assessing the probability of PDR pathogens.

Epidemiology and predictors of multidrug-resistant community-acquired and health care-associated pneumonia

There are limited U.S. data describing the risk factors for multidrug-resistant organism (MDRO) isolation in community-acquired pneumonia (CAP) and health care-associated pneumonia (HCAP). However, concern for the presence of these pathogens drives the prescribing of empiric broad-spectrum antibiotics for CAP and HCAP. A retrospective study of all adults hospitalized with community-onset pneumonia (CAP and HCAP) at a large U.S. medical center from January 2010 to December 2011 was conducted. The objective was to ascertain the rate of pneumonia caused by MDROs and to evaluate whether HCAP is a risk factor for MDRO pneumonia. Univariate and propensity score-adjusted multivariate analyses were performed. A total of 521 patients (50.5% CAP and 49.5% HCAP) were included. The most common etiologies of pneumonia were primary viral and Streptococcus pneumoniae. MDROs were isolated in 20 (3.8%) patients overall, and MDROs occurred in 5.9% and 1.9% of HCAP and CAP patients, respectively. The presence of an MDRO was not associated with HCAP classification (odds ratio [OR]=1.95; 95% confidence interval [95% CI], 0.66 to 5.80; P=0.23) or with most of its individual components (hemodialysis, home infusion, home wound care, and ≥48-h hospitalization in the last 90 days). Independent predictors of MDRO included the following: Pseudomonas aeruginosa colonization/infection in the previous year (OR=7.43; 95% CI, 2.24 to 24.61; P<0.001), antimicrobial use in the previous 90 days (OR=2.90; 95% CI, 1.13 to 7.45; P=0.027), admission from a nursing home (OR=4.19; 95% CI, 1.55 to 11.31; P=0.005), and duration of hospitalization in the previous 90 or 180 days (P=0.013 and P=0.002, respectively). MDROs were uncommon in HCAP and CAP. HCAP did not predict MDRO isolation. Local etiology of community onset pneumonia and specific MDRO risk factors should be integrated into therapeutic decisions to prevent empirical overprescribing of antibiotics for methicillin-resistant Staphylococcus aureus (MRSA) and P. aeruginosa.

Healthcare-associated pneumonia: a US disease or relevant to the Asia Pacific, too?

The term 'health care-associated pneumonia' (HCAP) was introduced by the American Thoracic Society and the Infectious Diseases Society of America in 2005 to describe a distinct entity of pneumonia that resembles hospital-acquired pneumonia rather than community-acquired pneumonia (CAP) in terms of occurrence of drug-resistant pathogens and mortality in patients that--while not hospitalized in the traditional sense--have been in recent contact with the health-care system. It was proposed that HCAP should be treated empirically with therapy for drug-resistant pathogens. Over the last few years, there has been increasing controversy over whether HCAP is a helpful definition, or leads to unnecessary and potentially problematic overtreatment. The term HCAP has been extensively criticized in Europe. While most studies have shown that HCAP is associated with more frequent drug-resistant pathogens and higher mortality than CAP, there is no clear evidence that this is due to inappropriate antibiotic therapy. Therapy consistent with HCAP treatment guidelines has also not been found to improve mortality. Based on current evidence, we suggest broad-spectrum antibiotic therapy to treat possible pathogens not usually covered in CAP be based on assessment of individual risk factors rather than applying a HCAP classification system in the Asia-Pacific Region.

[Empiric therapy protocol for nosocomial pneumonia]

La neumonía nosocomial representa una de las complicaciones infecciosas más frecuentes en los pacientes ingresados en los hospitales, asociando una elevada morbilidad y mortalidad. El tratamiento de estos enfermos se establece de forma empírica, debe ser lo más precoz posible para mejorar su pronóstico clínico y además en la mayoría de los casos no se obtiene una documentación microbiológica sobre la etiología de los mismos, por lo que queda bien establecida la necesidad de contar con protocolos de actuación claros y dirigidos a todos los profesionales médicos que se encargan de la atención de estos pacientes.

The management of community-acquired pneumonia in the elderly

Pneumonia is one of the main causes of morbidity and mortality in the elderly. The elderly population has exponentially increased in the last decades and the current epidemiological trends indicate that it is expected to further increase. Therefore, recognizing the special needs of older people is of paramount importance. In this review we address the main differences between elderly and adult patients with pneumonia. We focus on several aspects, including the atypical clinical presentation of pneumonia in the elderly, the methods to assess severity of illness, the appropriate setting of care, and the management of comorbidities. We also discuss how to approach the common complications of severe pneumonia, including acute respiratory failure and severe sepsis. Moreover, we debate whether or not elderly patients are at higher risk of infection due to multi-drug resistant pathogens and which risk factors should be considered when choosing the antibiotic therapy. We highlight the differences in the definition of clinical stability and treatment failure between adults and elderly patients. Finally, we review the main outcomes, preventive and supportive measures to be considered in elderly patients with pneumonia.

Healthcare-associated Pneumonia and Aspiration Pneumonia

Healthcare-associated pneumonia (HCAP) is a new concept of pneumonia proposed by the American Thoracic Society/Infectious Diseases Society of America in 2005. This category is located between community-acquired pneumonia and hospital-acquired pneumonia with respect to the characteristics of the causative pathogens and mortality, and primarily targets elderly patients in healthcare facilities. Aspiration among such patients is recognized to be a primary mechanism for the development of pneumonia, particularly since the HCAP guidelines were published. However, it is difficult to manage patients with aspiration pneumonia because the definition of the condition is unclear, and the treatment is associated with ethical aspects. This review focused on the definition, prevalence and role of aspiration pneumonia as a prognostic factor in published studies of HCAP and attempted to identify problems associated with the concept of aspiration pneumonia.

Clinical implications for patients treated inappropriately for community-acquired pneumonia in the emergency department

Background

Community-acquired pneumonia (CAP) is one of the most common infections presenting to the emergency department (ED). Increasingly, antibiotic resistant bacteria have been identified as causative pathogens in patients treated for CAP, especially in patients with healthcare exposure risk factors.

Methods

We retrospectively identified adult subjects treated for CAP in the ED requiring hospital admission (January 2003-December 2011). Inappropriate antibiotic treatment, defined as an antibiotic regimen that lacked in vitro activity against the isolated pathogen, served as the primary end point. Information regarding demographics, severity of illness, comorbidities, and antibiotic treatment was recorded. Logistic regression was used to determine factors independently associated with inappropriate treatment.

Results

The initial cohort included 259 patients, 72 (27.8%) receiving inappropriate antibiotic treatment. There was no difference in hospital mortality between patients receiving inappropriate and appropriate treatment (8.3% vs. 7.0%; p = 0.702). Hospital length of stay (10.3 ± 12.0 days vs. 7.0 ± 8.9 days; p = 0.017) and 30-day readmission (23.6% vs. 12.3%; p = 0.024) were greater among patients receiving inappropriate treatment. Three variables were independently associated with inappropriate treatment: admission from long-term care (AOR, 9.05; 95% CI, 3.93-20.84), antibiotic exposure in the previous 30 days (AOR, 1.85; 95% CI, 1.35-2.52), and chronic obstructive pulmonary disease (AOR, 2.05; 95% CI, 1.52-2.78).

Conclusion

Inappropriate antibiotic treatment of presumed CAP in the ED negatively impacts patient outcome and readmission rate. Knowledge of risk factors associated with inappropriate antibiotic treatment of presumed CAP could advance the management of patients with pneumonia presenting to the ED and potentially improve patient outcomes.

Community-Acquired Pneumonia

Community-acquired pneumonia (CAP) is a leading cause of morbidity and mortality in the world, with an annual incidence ranking from 1.6 to 10.6 per 1.000 people in Europe. The incidence is age related, peaking over 65 years. Up to 75 % of CAP patients with pulmonary diseases need hospitalization, and up to a 10 % of these are admitted to an intensive care unit (ICU) due to complications like sepsis, septic shock, and acute respiratory distress syndrome (ARDS) [1–3]. Up to 8 % of CAP patients die within 90 days of disease onset; 21 % die within a year [4] making CAP the most frequent cause of death from infection in Europe and the third most common cause of death in general [5]. Mortality is highest in ICU patients.

Risk factors for drug-resistant pathogens in community-acquired and healthcare-associated pneumonia

RATIONALE

Identification of patients with drug-resistant pathogens at initial diagnosis is essential for treatment of pneumonia.

OBJECTIVES

To elucidate clinical features of community-acquired pneumonia (CAP) and healthcare-associated pneumonia (HCAP), and to clarify risk factors for drug-resistant pathogens in patients with CAP and HCAP.

METHODS

A prospective observational study was conducted in hospitalized patients with pneumonia at 10 institutions in Japan. Pathogens identified as not susceptible to ceftriaxone, ampicillin-sulbactam, macrolides, and respiratory fluoroquinolones were defined as CAP drug-resistant pathogens (CAP-DRPs).

MEASUREMENTS AND MAIN RESULTS

In total, 1,413 patients (887 CAP and 526 HCAP) were analyzed. CAP-DRPs were more frequently found in patients with HCAP (26.6%) than in patients with CAP (8.6%). Independent risk factors for CAP-DRPs were almost identical in patients with CAP and HCAP. These included prior hospitalization (adjusted odds ratio [AOR], 2.06; 95% confidence interval [CI], 1.23-3.43), immunosuppression (AOR, 2.31; 95% CI, 1.05-5.11), previous antibiotic use (AOR, 2.45; 95% CI, 1.51-3.98), use of gastric acid-suppressive agents (AOR, 2.22; 95% CI, 1.39-3.57), tube feeding (AOR, 2.43; 95% CI, 1.18-5.00), and nonambulatory status (AOR, 2.45; 95% CI, 1.40-4.30) in the combined patients with CAP and HCAP. The area under the receiver operating characteristic curve for counting the number of risk factors was 0.79 (95% CI, 0.74-0.84).

CONCLUSIONS

The clinical profile of HCAP was different from that of CAP. However, physicians can predict drug resistance in patients with either CAP or HCAP by taking account of the cumulative number of the risk factors. Clinical trial registered with https://upload.umin.ac.jp/cgi-open-bin/ctr/ctr.cgi?function=brows&action=brows&type=summary&recptno=R000004001&language=E ; number UMIN000003306.

Microbial aetiology of healthcare associated pneumonia in Spain: a prospective, multicentre, case-control study

INTRODUCTION

Healthcare-associated pneumonia (HCAP) is actually considered a subgroup of hospital-acquired pneumonia due to the reported high risk of multidrug-resistant pathogens in the USA. Therefore, current American Thoracic Society/Infectious Diseases Society of America guidelines suggest a nosocomial antibiotic treatment for HCAP. Unfortunately, the scientific evidence supporting this is contradictory.

METHODS

We conducted a prospective multicentre case-control study in Spain, comparing clinical presentation, outcomes and microbial aetiology of HCAP and community-acquired pneumonia (CAP) patients matched by age (±10 years), gender and period of admission (±10 weeks).

RESULTS

476 patients (238 cases, 238 controls) were recruited for 2 years from June 2008. HCAP cases showed significantly more comorbidities (including dysphagia), higher frequency of previous antibiotic use in the preceding month, higher pneumonia severity score and worse clinical status (Charslon and Barthel scores). While microbial aetiology did not differ between the two groups (HCAP and CAP: Streptococcus pneumoniae: 51% vs 55%; viruses: 22% vs 12%; Legionella: 4% vs 9%; Gram-negative bacilli: 5% vs 4%; Pseudomonas aeruginosa: 4% vs 1%), HCAP patients showed worse mortality rates (1-month: HCAP, 12%; CAP 5%; 1-year: HCAP, 24%; CAP, 9%), length of hospital stay (9 vs 7 days), 1-month treatment failure (5.5% vs 1.5%) and readmission rate (18% vs 11%) (p<0.05, each).

CONCLUSIONS

Despite a similar clinical presentation, HCAP was more severe due to patients' conditions (comorbidities) and showed worse clinical outcomes. Microbial aetiology of HCAP did not differ from CAP indicating that it is not related to increased mortality and in Spain most HCAP patients do not need nosocomial antibiotic coverage.

Pneumonia burden in elderly patients: a classification algorithm using administrative data

BACKGROUND

Pneumonia has traditionally been classified into two subtypes: community-acquired pneumonia (CAP) and nosocomial pneumonia (NP). Recently, a new entity has been defined, called healthcare-associated pneumonia (HCAP). Few studies have investigated the potential of population-based, electronic, healthcare databases to identify the incidences of these three subtypes of pneumonia. The aim of this study was to estimate the burden of the three subtypes of pneumonia in elderly patients (aged 65+ years) in a large region of central Italy.

METHODS

A retrospective cohort study was performed using linked regional Hospital Information System and Mortality Register. All episodes of pneumonia in elderly patients, who were discharged from the hospital in 2006-2008, were selected for the study. Following a validated ICD-9-coding algorithm, incidents of pneumonia events were classified into three groups (HCAP; probable nosocomial pneumonia, PNP; and CAP). Hospitalisation rates were calculated by age group (65-79, 80+), gender, and year, using the population from the Institute of Statistics (ISTAT) census estimates as denominators.

RESULTS

A total of 26,239 pneumonia events occurred in 24,338 patients residing in the Lazio region, aged 65+ years: 2257 HCAP, 6775 PNP, and 17,107 CAP. For all subtypes, the proportion of males was greater than females. Comorbidity status was more severe in HCAP than in the other categories. In-hospital mortality, 30-day mortality, and length of hospital stay were twice higher in HCAP than in CAP episodes. The annual incidence rates were 0.7, 2.1, and 5.4 episodes per 1000 residents for HCAP, PNP, and CAP, respectively. From 2006 to 2008, incidence rates slightly increased for all three subtypes.

CONCLUSION

Health care databases can be used to give a timely and inexpensive picture of the epidemiology of pneumonia. HCAP represents a distinct category of pneumonia, with the longest stay, highest mortality, and the greatest comorbidity.

Is the present definition of health care-associated pneumonia the best way to define risk of infection with antibiotic-resistant pathogens?

Health care-associated pneumonia (HCAP) is associated with an increased risk of infection with multidrug-resistant pathogens compared with community-acquired pneumonia. Recent studies suggest that the designation of HCAP is a poor predictor of resistant pathogens and that antibiotic coverage for multidrug-resistant pathogens is not necessary in all patients with HCAP. This article reviews existing literature on HCAP, discusses the utility of the current definition of HCAP in identifying patients at risk for potentially drug-resistant pathogens, and compares how well the current HCAP designation predicts the risk of drug-resistant pathogens with other proposed algorithms for doing so.

Does health care associated pneumonia really exist?

The most recent ATS guidelines for nosocomial pneumonia of 2005 describe a new clinical category of patients, Health Care-Associated Pneumonia which includes a number of very heterogeneous conditions possibly associated with a high risk of multi-drug resistant (MDR) infections and of mortality. This paper aims at reviewing the current literature on HCAP and examines the controversial issues of HCAP etiology and outcomes, underlining the need of a profound revision of the HCAP concept in the face of the poor and contrasting scientific evidence supporting its basis.