Proposed changes to management of lower respiratory tract infections in response to the Clostridium difficile epidemic

Risk assessment and prediction of nosocomial infections based on surveillance data using machine learning methods

BACKGROUND

Nosocomial infections with heavy disease burden are becoming a major threat to the health care system around the world. Through long-term, systematic, continuous data collection and analysis, Nosocomial infection surveillance (NIS) systems are constructed in each hospital; while these data are only used as real-time surveillance but fail to realize the prediction and early warning function. Study is to screen effective predictors from the routine NIS data, through integrating the multiple risk factors and Machine learning (ML) methods, and eventually realize the trend prediction and risk threshold of Incidence of Nosocomial infection (INI).

METHODS

We selected two representative hospitals in southern and northern China, and collected NIS data from 2014 to 2021. Thirty-nine factors including hospital operation volume, nosocomial infection, antibacterial drug use and outdoor temperature data, etc. Five ML methods were used to fit the INI prediction model respectively, and to evaluate and compare their performance.

RESULTS

Compared with other models, Random Forest showed the best performance (5-fold AUC = 0.983) in both hospitals, followed by Support Vector Machine. Among all the factors, 12 indicators were significantly different between high-risk and low-risk groups for INI (P < 0.05). After screening the effective predictors through importance analysis, prediction model of the time trend was successfully constructed (R2 = 0.473 and 0.780, BIC = -1.537 and -0.731).

CONCLUSIONS

The number of surgeries, antibiotics use density, critical disease rate and unreasonable prescription rate and other key indicators could be fitted to be the threshold predictions of INI and quantitative early warning.

Systemic steroid therapy for pneumonic chronic obstructive pulmonary disease exacerbation: A retrospective cohort study

The effectiveness of systemic steroid therapy on mortality in patients with pneumonic chronic obstructive pulmonary disease (COPD) exacerbation is unclear. We evaluated the association between systemic steroid therapy and 30-day mortality after adjusting for known confounders, using data from the Health, Clinic, and Education Information Evaluation Institute in Japan, which longitudinally followed up patients in the same hospital. We selected patients aged ≥40 years admitted for pneumonic COPD exacerbation. The exclusion criteria were censoring within 24 h, comorbidity with other respiratory diseases, and daily steroid use. Systemic steroid therapy was defined as oral/parenteral steroid therapy initiated within two days of admission. The primary outcome was the 30-day mortality rate. To account for known confounders, each patient was assigned an inverse probability of treatment weighting. The outcome was evaluated using logistic regression. Among 3,662 patients showing pneumonic COPD exacerbation, 30-day mortality in the steroid therapy and non-steroid therapy groups was 27.6% (169/612) and 21.9% (668/3,050), respectively. Systemic steroid therapy indicated a slightly higher estimated probability of 30-day mortality (difference in the estimated probabilities, 2.65%; 95% confidence interval, -1.23 to 6.54%, p-value = 0.181). Systemic steroid therapy within two days of admission was associated with higher 30-day mortality rates in pneumonic COPD exacerbation. Further validation studies based on chart reviews will be needed to cope with residual confounders.

Identify Drug-Resistant Pathogens in Patients with Community-Acquired Pneumonia

A substantial increase in broad-spectrum antibiotics as empirical therapy in patients with community-acquired pneumonia (CAP) has occurred over the last 15 years. One of the driving factors leading to that has been some evidence showing an increased incidence of drug-resistant pathogens (DRP) in patients from a community with pneumonia, including methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa. Research has been published attempting to identify DRP in CAP through the implementation of probabilistic approaches in clinical practice. However, recent epidemiological data showed that the incidence of DRP in CAP varies significantly according to local ecology, healthcare systems and countries where the studies were performed. Several studies also questioned whether broad-spectrum antibiotic coverage might improve outcomes in CAP, as it is widely documented that broad-spectrum antibiotics overuse is associated with increased costs, length of hospital stay, drug adverse events and resistance. The aim of this review is to analyze the different approaches used to identify DRP in CAP patients as well as the outcomes and adverse events in patients undergoing broad-spectrum antibiotics.

Association of fluoroquinolones or cephalosporin plus macrolide with Clostridioides difficile infection (CDI) after treatment for community-acquired pneumonia

OBJECTIVE

Clostridioides difficile infection (CDI) is the most common cause of gastroenteritis, and community-acquired pneumonia (CAP) is the most common infection treated in hospitals. American Thoracic Society (ATS)/Infectious Diseases Society of America (IDSA) CAP guidelines recommend empiric therapy with a respiratory fluoroquinolone or cephalosporin plus macrolide combination, but the CDI risk of these regimens is unknown. We examined the association between each antibiotic regimen and the development of hospital-onset CDI.

METHODS

We conducted a retrospective cohort study using data from 638 US hospitals contributing administrative including 177 also contributing microbiologic data to Premier, Inc. We included adults admitted with pneumonia and discharged from July 2010 through June 2015 with a pneumonia diagnosis code who received ≥3 days of either empiric regimen. Hospital-onset CDI was defined by a diagnosis code not present on admission and positive laboratory test on day 4 or later or readmission for CDI. Mixed propensity-weighted multiple logistic regression was used to estimate the associations of CDI with antibiotic regimens.

RESULTS

Our sample included 58,060 patients treated with either cephalosporin plus macrolide (36,796 patients) or a fluoroquinolone alone (21,264 patients) and with microbiological data; 127 (0.35%) patients who received cephalosporin plus macrolide and 65 (0.31%) who received a fluoroquinolone developed CDI. After adjustment for patient demographics, comorbidities, risk factors for antimicrobial resistance, and hospital characteristics, CDI risks were similar for fluoroquinolones versus cephalosporin plus macrolide (odds ratio [OR], 0.98; 95% confidence interval [CI], 0.70-1.38).

CONCLUSION

Among patients with CAP at US hospitals, CDI was uncommon, occurring in ∼0.33% of patients. We did not detect a significant association between the choice of empiric guideline recommended antibiotic therapy and the development of CDI.

Clostridioides difficile infection after pneumonia in older patients: Which antibiotic is at lower risk?

BACKGROUND

Clostridioides difficile infection (CDI) is a frequent and severe complication of antibiotic treatment in older patients hospitalized for acute pneumonia (AP).

AIMS

We aimed to assess the burden and risk factors of CDI and to determine which of the usual antibiotics regimens is at lower risk for post-AP CDI incidence.

METHODS

Among patients aged >75y hospitalized for AP in all departments of a university hospital between 2007 and 2017, all the 92 patients developing a CDI were compared with 213 patients without CDI. Factors associated with 1) in-hospital and one-year mortality, 2) CDI incidence were assessed using logistic regression models.

FINDINGS

In patients with and without CDI after AP, mortality rates were respectively at 34% vs 20% in hospital and 63% vs 42% at one-year. After adjustment for confounders, CDI was associated with a two-fold risk of in-hospital and one-year mortality after pneumonia (Respective Odds Ratio (95% Confidence Interval), OR (95%CI): 1.95 (1.06-3.58) and 2.02 (1.43-7.31)). High number of antibiotics (Per antibiotic, OR (95%CI): 1.89 (1.18-3.06)), rather than antibiotics duration (Per day, OR 95%CI): 1.04 (0.96-1.11)) was associated with a higher risk of CDI. Compared with other antibiotics, use of penicillin + beta-lactamase inhibitors was associated with a lower risk of CDI (OR (95%CI): 0.43 (0.19 -0.99)) CONCLUSION: In older inpatients, CDI highly increase the burden of AP at both short and long term. If confirmed, these results suggest the preferential use of penicillin + beta-lactamase inhibitors for a lower incidence of CDI in older inpatients with AP.

Broad-spectrum antibiotic use and poor outcomes in community-onset pneumonia: a cohort study

QUESTION

Is broad-spectrum antibiotic use associated with poor outcomes in community-onset pneumonia after adjusting for confounders?

METHODS

We performed a retrospective, observational cohort study of 1995 adults with pneumonia admitted from four US hospital emergency departments. We used multivariable regressions to investigate the effect of broad-spectrum antibiotics on 30-day mortality, length of stay, cost and Clostridioides difficile infection (CDI). To address indication bias, we developed a propensity score using multilevel (individual provider) generalised linear mixed models to perform inverse-probability of treatment weighting (IPTW) to estimate the average treatment effect in the treated. We also manually reviewed a sample of mortality cases for antibiotic-associated adverse events.

RESULTS

39.7% of patients received broad-spectrum antibiotics, but drug-resistant pathogens were recovered in only 3%. Broad-spectrum antibiotics were associated with increased mortality in both the unweighted multivariable model (OR 3.8, 95% CI 2.5-5.9; p<0.001) and IPTW analysis (OR 4.6, 95% CI 2.9-7.5; p<0.001). Broad-spectrum antibiotic use by either analysis was also associated with longer hospital stay, greater cost and increased CDI. Healthcare-associated pneumonia was not associated with mortality independent of broad-spectrum antibiotic use. In manual review we identified antibiotic-associated events in 17.5% of mortality cases.

CONCLUSION

Broad-spectrum antibiotics appear to be associated with increased mortality and other poor outcomes in community-onset pneumonia.

CRP-guided antibiotic treatment in acute exacerbations of COPD in hospital admissions

The role of antibiotics in acute exacerbations of chronic obstructive pulmonary disease (COPD) is controversial and a biomarker identifying patients who benefit from antibiotics is mandatory. We performed a randomised, controlled trial in patients with acute exacerbations of COPD, comparing C-reactive protein (CRP)-guided antibiotic treatment to patient reported symptoms in accordance with the Global Initiative for Chronic Obstructive Lung Disease (GOLD) strategy, in order to show a reduction in antibiotic prescription.Patients hospitalised with acute exacerbations of COPD were randomised to receive antibiotics based either on the GOLD strategy or according to the CRP strategy (CRP ≥50 mg·L^-1).In total, 101 patients were randomised to the CRP group and 119 to the GOLD group. Fewer patients in the CRP group were treated with antibiotics compared to the GOLD group (31.7% versus 46.2%, p=0.028; adjusted odds ratio (OR) 0.178, 95% CI 0.077-0.411, p=0.029). The 30-day treatment failure rate was nearly equal (44.5% in the CRP group versus 45.5% in the GOLD-group, p=0.881; adjusted OR 1.146, 95% CI 0.649-1.187, p=0.630), as was the time to next exacerbation (32 days in the CRP group versus 28 days in the GOLD group, p=0.713; adjusted hazard ratio 0.878, 95% CI 0.649-1.187, p=0.398). Length of stay was similar in both groups (7 days in the CRP group versus 6 days in the GOLD group, p=0.206). On day-30, no difference in symptom score, quality of life or serious adverse events was detected.Use of CRP as a biomarker to guide antibiotic treatment in severe acute exacerbations of COPD leads to a significant reduction in antibiotic treatment. In the present study, no differences in adverse events between both groups were found. Further research is needed for the generalisability of these findings.

Antibiotic Use and Outcomes After Implementation of the Drug Resistance in Pneumonia Score in ED Patients With Community-Onset Pneumonia

BACKGROUND

To guide rational antibiotic selection in community-onset pneumonia, we previously derived and validated a novel prediction tool, the Drug-Resistance in Pneumonia (DRIP) score. In 2015, the DRIP score was integrated into an existing electronic pneumonia clinical decision support tool (ePNa).

METHODS

We conducted a quasi-experimental, pre-post implementation study of ePNa with DRIP score (2015) vs ePNa with health-care-associated pneumonia (HCAP) logic (2012) in ED patients admitted with community-onset pneumonia to four US hospitals. Using generalized linear models, we used the difference-in-differences method to estimate the average treatment effect on the treated with respect to ePNa with DRIP score on broad-spectrum antibiotic use, mortality, hospital stay, and cost, adjusting for available patient-level confounders.

RESULTS

We analyzed 2,169 adult admissions: 1,122 in 2012 and 1,047 in 2015. A drug-resistant pathogen was recovered in 3.2% of patients in 2012 and 2.8% in 2015; inadequate initial empirical antibiotics were prescribed in 1.1% and 0.5%, respectively (P = .12). A broad-spectrum antibiotic was administered in 40.1% of admissions in 2012 and 33.0% in 2015 (P < .001). Vancomycin days of therapy per 1,000 patient days in 2012 were 287.3 compared with 238.8 in 2015 (P < .001). In the primary analysis, the average treatment effect among patients using the DRIP score was a reduction in broad-spectrum antibiotic use (OR, 0.62; 95% CI, 0.39-0.98; P = .039). However, the average effects for ePNa with DRIP on mortality, length of stay, and cost were not statistically significant.

CONCLUSIONS

Electronic calculation of the DRIP score was more effective than HCAP criteria for guiding appropriate broad-spectrum antibiotic use in community-onset pneumonia.

The burden of community-acquired bacterial pneumonia in the era of antibiotic resistance

INTRODUCTION

Community-acquired pneumonia (CAP) is a significant global health problem and leading cause of death and hospitalization in both the US and abroad. Increasing macrolide resistance among Streptococcus pneumoniae and other pathogens results in a greater disease burden, along with changing demographics and a higher preponderance of comorbid conditions. Areas covered: This review summarizes current data on the clinical and economic burden of CAP, with particular focus on community-acquired bacterial pneumonia (CABP). Incidence, morbidity and mortality, and healthcare costs for the US and other regions of the world are among the topics covered. Major factors that are believed to be contributing to the increased impact of CABP, including antimicrobial resistance, the aging population, and the incidence of comorbidities are discussed, as well as unmet needs in current CABP management. Expert commentary: The clinical and economic burden of CABP is staggering, far-reaching, and expected to increase in the future as new antibiotic resistance mechanisms emerge and the world's population ages. Important measures must be initiated to stabilize and potentially decrease this burden. Urgent needs in CABP management include the development of new antimicrobials, adjuvant therapies, and rapid diagnostics.

A Pilot Feasibility Study in Establishing the Role of Ultrasound-Guided Pleural Biopsies in Pleural Infection (The AUDIO Study)

BACKGROUND

Pleural infection is a common complication of pneumonia associated with high mortality and poor clinical outcome. Treatment of pleural infection relies on the use of broad-spectrum antibiotics because reliable pathogen identification occurs infrequently. We performed a feasibility interventional clinical study assessing the safety and significance of ultrasound (US)-guided pleural biopsy culture to increase microbiological yield. In an exploratory investigation, the 16S ribosomal RNA technique was applied to assess its utility on increasing speed and accuracy vs standard microbiological diagnosis.

METHODS

Twenty patients with clinically established pleural infection were recruited. Participants underwent a detailed US scan and US-guided pleural biopsies before chest drain insertion, alongside standard clinical management. Pleural biopsies and routine clinical samples (pleural fluid and blood) were submitted for microbiological analysis.

RESULTS

US-guided pleural biopsies were safe with no adverse events. US-guided pleural biopsies increased microbiological yield by 25% in addition to pleural fluid and blood samples. The technique provided a substantially higher microbiological yield compared with pleural fluid and blood culture samples (45% compared with 20% and 10%, respectively). The 16S ribosomal RNA technique was successfully applied to pleural biopsy samples, demonstrating high sensitivity (93%) and specificity (89.5%).

CONCLUSIONS

Our findings demonstrate the safety of US-guided pleural biopsies in patients with pleural infection and a substantial increase in microbiological diagnosis, suggesting potential niche of infection in this disease. Quantitative polymerase chain reaction primer assessment of pleural fluid and biopsy appears to have excellent sensitivity and specificity.

Health care-associated pneumonia in the intensive care unit: Guideline-concordant antibiotics and outcomes

PURPOSE

Recent data have not demonstrated improved outcomes when guideline-concordant (GC) antibiotics are given to patients with health care-associated pneumonia (HCAP). This study was designed to evaluate the relationship between health outcomes and GC therapy in patients admitted to an intensive care unit (ICU) with HCAP.

MATERIALS AND METHODS

We performed a population-based cohort study of patients admitted to greater than 150 hospitals in the US Veterans Health Administration system to compare baseline characteristics, bacterial pathogens, and health outcomes in ICU patients with HCAP receiving GC-HCAP therapy, GC community-acquired pneumonia (GC-CAP) therapy, or non-GC therapy. The primary outcome was 30-day patient mortality. Risk factors for the primary outcome were assessed in a multivariable logistic regression model.

RESULTS

A total of 3593 patients met inclusion criteria and received GC-HCAP therapy (26%), GC-CAP therapy (23%), or non-GC therapy (51%). Patients receiving GC-HCAP had higher 30-day patient mortality compared to GC-CAP patients (34% vs 22%; P< .0001). After controlling for confounders, risk factors for 30-day patient mortality were vasopressor use (odds ratio, 1.67; 95% confidence interval, 1.30-2.13), recent hospital admission (1.53; 1.15-2.02), and receipt of GC-HCAP therapy (1.51; 1.20-1.90).

CONCLUSIONS

Our data do not demonstrate improved outcomes among ICU patients with HCAP who received GC-HCAP therapy.

Empiric antibiotic selection and risk prediction of drug-resistant pathogens in community-onset pneumonia

PURPOSE OF REVEIW

Empiric antibiotic selection in community-onset pneumonia is complicated by uncertainty regarding risk of drug-resistant pathogens (DRPs). The healthcare-associated pneumonia (HCAP) criteria have limited predictive value and lead to unnecessary antibiotic use. Better methods of predicting risk of DRP and selecting empiric antibiotics are needed. Here we give an update on risk factors for DRP, available risk prediction models, and treatment strategy in patients with pneumonia.

RECENT FINDINGS

Evidence supporting factors that contribute to risk of DRP has improved since the advent of HCAP. Many of these risk factors have been reproducibly identified in heterogeneous populations. Newer methods of predicting DRP based on these factors demonstrate better performance than HCAP. Recent innovations include the potential to discriminate between risk for methicillin-resistant Staphylococcus aureus and other DRP, and use of severity as a modifier of treatment threshold. However, there is wide variation in included predictor variables, and at proposed thresholds most scores still favor overtreatment.

SUMMARY

Until reliable molecular diagnostics are available, additional development and validation of decision support models integrating local resistance rates, estimated DRP risk, severity, and threshold for anti-DRP antibiotics are needed. Once optimized models are identified, implementation studies will be needed to confirm safety and efficacy.

Derivation and Multicenter Validation of the Drug Resistance in Pneumonia Clinical Prediction Score

The health care-associated pneumonia (HCAP) criteria have a limited ability to predict pneumonia caused by drug-resistant bacteria and favor the overutilization of broad-spectrum antibiotics. We aimed to derive and validate a clinical prediction score with an improved ability to predict the risk of pneumonia due to drug-resistant pathogens compared to that of HCAP criteria. A derivation cohort of 200 microbiologically confirmed pneumonia cases in 2011 and 2012 was identified retrospectively. Risk factors for pneumonia due to drug-resistant pathogens were evaluated by logistic regression, and a novel prediction score (the drug resistance in pneumonia [DRIP] score) was derived. The score was then validated in a prospective, observational cohort of 200 microbiologically confirmed cases of pneumonia at four U.S. centers in 2013 and 2014. The DRIP score (area under the receiver operator curve [AUROC], 0.88 [95% confidence interval {CI}, 0.82 to 0.93]) performed significantly better (P = 0.02) than the HCAP criteria (AUROC, 0.72 [95% CI, 0.64 to 0.79]). At a threshold of ≥4 points, the DRIP score demonstrated a sensitivity of 0.82 (95% CI, 0.67 to 0.88), a specificity of 0.81 (95% CI, 0.73 to 0.87), a positive predictive value (PPV) of 0.68 (95% CI, 0.56 to 0.78), and a negative predictive value (NPV) of 0.90 (95% CI, 0.81 to 0.93). By comparison, the performance of HCAP criteria was less favorable: sensitivity was 0.79 (95% CI, 0.67 to 0.88), specificity was 0.65 (95% CI, 0.56 to 0.73), PPV was 0.53 (95% CI, 0.42 to 0.63), and NPV was 0.86 (95% CI, 0.77 to 0.92). The overall accuracy of the HCAP criteria was 69.5% (95% CI, 62.5 to 75.7%), whereas that of the DRIP score was 81.5% (95% CI, 74.2 to 85.6%) (P = 0.005). Unnecessary extended-spectrum antibiotics were recommended 46% less frequently by applying the DRIP score (25/200, 12.5%) than by use of HCAP criteria (47/200, 23.5%) (P = 0.004), without increasing the rate at which inadequate treatment recommendations were made. The DRIP score was more predictive of the risk of pneumonia due to drug-resistant pathogens than HCAP criteria and may have the potential to decrease antibiotic overutilization in patients with pneumonia. Validation in larger cohorts of patients with pneumonia due to all causes is necessary.

Risk factors for Clostridium difficile infection in hospitalized patients with community-acquired pneumonia

OBJECTIVES

Clostridium difficile infection (CDI) is strongly associated with anti-biotic treatment, and community-acquired pneumonia (CAP) is the leading indication for anti-biotic prescription in hospitals. This study assessed the incidence of and risk factors for CDI in a cohort of patients hospitalized with CAP.

METHODS

We analysed data from a prospective, observational cohort of patients with CAP in Edinburgh, UK. Patients with diarrhoea were systematically screened for CDI, and risk factors were determined through time-dependent survival analysis.

RESULTS

Overall, 1883 patients with CAP were included, 365 developed diarrhoea and 61 had laboratory-confirmed CDI. The risk factors for CDI were: age (hazard ratio [HR], 1.06 per year; 95% confidence interval [CI], 1.03-1.08), total number of antibiotic classes received (HR, 3.01 per class; 95% CI, 2.32-3.91), duration of antibiotic therapy (HR, 1.09 per day; 95% CI, 1.00-1.19 and hospitalization status (HR, 13.1; 95% CI, 6.0-28.7). Antibiotic class was not an independent predictor of CDI when adjusted for these risk factors (P > 0.05 by interaction testing).

CONCLUSIONS

These data suggest that reducing the overall antibiotic burden, duration of antibiotic treatment and duration of hospital stay may reduce the incidence of CDI in patients with CAP.

Usefulness of midregional proadrenomedullin to predict poor outcome in patients with community acquired pneumonia

Background

midregional proadrenomedullin (MR-proADM) is a prognostic biomarker in patients with community-acquired pneumonia (CAP). We sought to confirm whether MR-proADM added to Pneumonia Severity Index (PSI) improves the potential prognostic value of PSI alone, and tested to what extent this combination could be useful in predicting poor outcome of patients with CAP in an Emergency Department (ED).

Methods

Consecutive patients diagnosed with CAP were enrolled in this prospective, single-centre, observational study. We analyzed the ability of MR-proADM added to PSI to predict poor outcome using receiver operating characteristic (ROC) curves, logistic regression and risk reclassification and comparing it with the ability of PSI alone. The primary outcome was “poor outcome”, defined as the incidence of an adverse event (ICU admission, hospital readmission, or mortality at 30 days after CAP diagnosis).

Results

226 patients were included; 33 patients (14.6%) reached primary outcome. To predict primary outcome the highest area under curve (AUC) was found for PSI (0.74 [0.64-0.85]), which was not significantly higher than for MR-proADM (AUC 0.72 [0.63-0.81, p > 0.05]). The combination of PSI and MR-proADM failed to improve the predictive potential of PSI alone (AUC 0.75 [0.65-0.85, p=0.56]). Ten patients were appropriately reclassified when the combined PSI and MR-proADM model was used as compared with the model of PSI alone. Net reclassification improvement (NRI) index was statistically significant (7.69%, p = 0.03) with an improvement percentage of 3.03% (p = 0.32) for adverse event, and 4.66% (P = 0.02) for no adverse event.

Conclusion

MR-proADM in combination with PSI may be helpful in individual risk stratification for short-term poor outcome of CAP patients, allowing a better reclassification of patients compared with PSI alone.

Randomized double blind placebo-controlled study to demonstrate that antibiotics are not needed in moderate acute exacerbations of COPD--the ABACOPD study

Background

Antibiotic-resistant strains of pathogenic bacteria are increasingly prevalent in hospitals and the community. Acute exacerbations of COPD (AE-COPD) often result in administration of antibiotics although more than half of exacerbations are associated with detection of respiratory viruses and potentially pathogenic bacteria can only be detected in 20-30% of cases. There is a paucity of placebo-controlled clinical trials and up to today no single study has been powered sufficiently to prove the efficacy of antibiotic treatment in AE-COPD. Most studies so far did not include current standards of care comprising administration of systemic corticosteroids.

Methods/Design

A total of 980 patients with moderate acute exacerbations will be included in 22 German centers (hospitals and private practices). Patients will receive a standardized treatment for exacerbation including systemic corticosteroids, inhaled bronchodilators and supplementary oxygen if needed and will be randomized to additional treatment with placebo or antibiotic (oral sultamicillin) for five days.

The primary endpoint is clinical failure defined by need for additional antibiotic treatment until day 30. Secondary endpoints will assure that management of AE-COPD without antibiotics does not result either in increased occurrence of relapse, new exacerbations, prolonged recovery, or unwanted long-term consequences.

Discussion

ABACOPD will be the first sufficiently powered double-blind placebo-controlled study in the field to systematically assess the question whether antibiotics, known to increase antibiotic resistance, are really needed in a well-defined patient cohort receiving state-of-the art treatment in all other aspects.

Trial registration number

ClinicalTrials.gov: NCT01892488.

Predicting risk of drug-resistant organisms in pneumonia: moving beyond the HCAP model

BACKGROUND

Clinical management of community-acquired pneumonia (CAP) is increasingly complicated by antibiotic resistance. CAP due to pathogens resistant to guideline-recommended drugs (CAP-DRP) has increased. 2005 ATS/IDSA guidelines introduced a new category, healthcare-associated pneumonia (HCAP), and recommend extended-spectrum antibiotic treatment for patients meeting HCAP criteria. However, the predictive value of the HCAP model is limited and data suggest that outcomes are not improved using HCAP guideline-concordant therapy. Better methods to predict risk of CAP-DRP are needed.

METHODS

We reviewed currently published literature on the performance status of HCAP as a predictive tool and studies describing additional risk factors for CAP-DRP. We also summarize the performance characteristics of the currently published alternative clinical prediction scores and compare them to that of the HCAP model.

RESULTS

In addition to the five risk factors incorporated in HCAP, at least 13 other factors have been identified. The independent predictive value of any single factor is low, but accumulating factors results in increased risk of CAP-DRP. The performance characteristics of 9 clinical prediction scores are reviewed. Nearly all of the scores outperformed HCAP in their study populations. However, no single model has yet demonstrated adequate specificity to minimize unnecessary antibiotic use, while retaining sufficient sensitivity to prevent inadequate initial empiric antibiotic therapy when validated across a wide range of CAP-DRP prevalence.

CONCLUSIONS

Additional development and validation of prediction scores based upon more refined risk factors for CAP-DRP is needed. Once an accurate, adequately validated prediction score is available, an interventional trial will be needed to determine clinical impact.

Risk of Clostridium difficile infection in hospitalized patients receiving metronidazole for a non-C difficile infection

BACKGROUND & AIMS

Antibiotics often are given to prevent infections but also constitute a risk factor for Clostridium difficile infection (CDI). Metronidazole is an effective treatment for CDI. We investigated whether prophylactic administration of metronidazole to patients before they receive other antibiotics reduces the risk of CDI.

METHODS

We performed a retrospective cohort analysis of data collected from 12,026 high-risk patients admitted to Cleveland Clinic Foundation Hospitals from 2008 through 2012. High-risk patients were defined as age 55 or older who received a broad-spectrum antibiotic (piperacillin-tazobactam or ciprofloxacin) and a gastric acid suppressant (a proton pump inhibitor or a histamine-2 receptor blocker) during their hospitalization. Development of CDI was compared between patients who received metronidazole for non-CDI indications before broad-spectrum antibiotics (n = 811) and those who did not (n = 11,215). Logistic regression was used to control for patient demographics and comorbidities.

RESULTS

The rate of CDI was 1.4% (n = 11) among the patients who received metronidazole for non-CDI indications and 6.5% (n = 728) among those who did not. This was observed to be an 80% reduction in CDI among patients who received metronidazole (odds ratio, 0.21; 95% confidence interval, 0.11-0.38; P < .001), adjusted for age, sex, and comorbidities.

CONCLUSIONS

Based on a retrospective analysis, metronidazole might be used to prevent CDI in certain high-risk patients. Prospective controlled trials are necessary before making further recommendations.

Role of doxycycline in Clostridium difficile infection acquisition

OBJECTIVE

To evaluate and review the literature surrounding the potential protective benefit of tetracyclines, particularly doxycycline, in reducing Clostridium difficile infection (CDI) acquisition.

DATA SOURCES

MEDLINE/PubMed, Google Scholar, and International Pharmaceutical Abstracts were searched through January 2014 using the search terms doxycycline, tetracycline, and Clostridium difficile.

STUDY SELECTION AND DATA EXTRACTION

Relevant studies, case reports, and review articles were screened for inclusion. Bibliographies of articles were extensively reviewed for additional sources.

DATA SYNTHESIS

Doxycycline is a second-generation tetracycline antibiotic indicated for use in a variety of clinical syndromes and has activity against aerobic Gram-positive and -negative, anaerobic, and atypical bacteria as well as protozoan parasites. Although not used therapeutically to treat CDI, doxycycline may prevent or attenuate the virulence factors of toxigenic C difficile. Current literature does not indicate an increased risk of development of CDI with doxycycline use. In 3 retrospective studies, the use of doxycycline was associated with a protective effect.

CONCLUSIONS

Doxycycline has been shown to have potential protective effects against the development of CDI. Although further randomized placebo-controlled studies are needed, available data suggest that the use of doxycycline in place of alternative antimicrobials, when appropriate, may be a useful antimicrobial stewardship strategy aimed at reducing the incidence of CDI.

Evaluation of an early step-down strategy from intravenous anidulafungin to oral azole therapy for the treatment of candidemia and other forms of invasive candidiasis: results from an open-label trial

Background

Hospitalized patients are at increased risk for candidemia and invasive candidiasis (C/IC). Improved therapeutic regimens with enhanced clinical and pharmacoeconomic outcomes utilizing existing antifungal agents are still needed.

Methods

An open-label, non-comparative study evaluated an intravenous (IV) to oral step-down strategy. Patients with C/IC were treated with IV anidulafungin and after 5 days of IV therapy had the option to step-down to oral azole therapy (fluconazole or voriconazole) if they met prespecified criteria. The primary endpoint was the global response rate (clinical + microbiological) at end of treatment (EOT) in the modified intent-to-treat (MITT) population (at least one dose of anidulafungin plus positive Candida within 96 hours of study entry). Secondary endpoints included efficacy at other time points and in predefined patient subpopulations. Patients who stepped down early (≤ 7 days’ anidulafungin) were identified as the "early switch" subpopulation.

Results

In total, 282 patients were enrolled, of whom 250 were included in the MITT population. The MITT global response rate at EOT was 83.7% (95% confidence interval, 78.7–88.8). Global response rates at all time points were generally similar in the early switch subpopulation compared with the MITT population. Global response rates were also similar across multiple Candida species, including C. albicans, C. glabrata, and C. parapsilosis. The most common treatment-related adverse events were nausea and vomiting (four patients each).

Conclusions

A short course of IV anidulafungin, followed by early step-down to oral azole therapy, is an effective and well-tolerated approach for the treatment of C/IC.

Trial registration

ClinicalTrials.gov: NCT00496197

Antibiotic intravenous-to-oral switch guidelines: barriers to adherence and possible solutions

Objectives

To identify reasons for poor adherence to antibiotic intravenous-to-oral switch guidelines and to explore the possible solutions. To rate the importance of the barriers and solutions identified, as perceived by a multidisciplinary expert panel.

Methods

Three-round Delphi study in an expert panel comprising doctors, nurses and pharmacists, with concurrent semi-structured interviews.

Key findings

The three rounds of the Delphi were completed by 13 out of the 30 healthcare professionals invited to participate. No nurses were included in the final round. Consensus was achieved for 28 out of 35 statements, with the most important barrier being that of inappropriate antibiotic review at the weekend, and the most important solution being to raise guideline awareness. The findings from the seven interviews (three doctors, two pharmacists and two nurses) complemented those from the Delphi study, although they provided more specific suggestions on how to improve the adherence to guidelines.

Conclusion

This study, using a combination of quantitative and qualitative methods, has identified several barriers to explore further and offered many practical solutions to improve practice. The importance of a multidisciplinary approach to address guideline non-adherence was emphasised. Clinical guidelines must be well publicised and well written to prevent a feeling of guideline saturation in the healthcare populous. Novel approaches may have to be investigated in order to further encourage adherence with antibiotic intravenous-to-oral switch guidelines.

External validation of the CURSI criteria (confusion, urea, respiratory rate and shock index) in adults hospitalised for community-acquired pneumonia

Background

For patients hospitalised due to community-acquired pneumonia (CAP), mortality risk is usually estimated with prognostic scores such as CRB-65 or CURB-65. For elderly patients, a new score referred to as CURSI has been proposed which uses shock index (SI) instead of the blood pressure (B) and age (65) criteria. The new score has not been externally validated to date.

Methods

We used data from a hospital-based CAP registry to compare the ability of CURSI, CURB-65 and CRB-65 to predict mortality at day 30 after hospital admission. Patients were stratified by score points as well as score-point-based risk categories, and mortality for each group was assessed. To compare test performance, receiver-operating characteristic (ROC) curves were constructed, and the areas under the curve (AUROC) were calculated with 95% confidence intervals (CI).

Results

We analysed 553 inpatients (45% females, median age 78 years) hospitalised between 2005 and 2009 for CAP. Overall, mortality at day 30 was 11% (59/553). The study sample was characterised by advanced comorbidity (chronic heart failure: 22%, chronic kidney failure: 27%) and functional impairment (nursing home residency: 26%, dementia: 31%). All risk scores were significantly associated with 30-day mortality. The AUROC values with 95% CI using score points for risk prediction were as follows: 0.63 [0.56-0.71] for CRB-65, 0.68 [0.61-0.75] for CURB-65 and 0.68 [0.61-0.75] for CURSI. The CURSI-defined low-risk group (0 or 1 score point) had a higher mortality (8%) than the low-risk groups defined by CURB-65 and CRB-65 (4% and 3%, respectively). Lowering the cut-off for the CURSI-defined low-risk group (0 point only) would lower the mortality to 4%, making it comparable to the CURB-65-defined low-risk group.

Conclusions

In our study, the CURSI-defined low-risk group had a higher 30-day mortality than the low-risk groups defined by CURB-65 and CRB-65. Lowering the cut-off value for the CURSI low-risk group would result in a mortality comparable to the CURB-65-defined low risk group. Even then, however, CURSI does not perform better than the established risk scores.

The role of healthcare strategies in controlling antibiotic resistance

In an interview in March 2013, the Chief Medical Officer described antibiotic resistance as a 'ticking time bomb' and ranked it along with terrorism on a list of threats to the nation. Her report Infections and the Rise of Antimicrobial Resistance (Department of Health, 2011) highlighted that, while a new infectious disease has been discovered nearly every year over the past three decades, there have been very few new antibiotics developed, leaving our armoury nearly empty. Antibiotic resistance is a universal problem that needs to be tackled by a wide variety of strategies and players. Our approach to tackling resistance to antibiotic agents must therefore also be dynamic. As well as reducing environmental use, we also need to lower antibiotic use in the healthcare setting. Healthcare workers have a huge role to play in combating antibiotic resistance. This article focuses on several issues related to antibiotic resistance, including antibiotic modes of action and the properties that confer resistance on bacteria. It includes information on antibiotic usage and describes current healthcare strategies we can adopt to help reduce the development of resistance.

Inappropriate use of antibiotics and Clostridium difficile infection

We assessed appropriateness of preceding and concurrent antibiotics in 126 consecutive patients with hospital-associated Clostridium difficile infection. In 93 (73.8%) episodes, at least 1 preceding course of antibiotics was inappropriate. We provided feedback on concurrent antibiotics on the day of diagnosis during the final 8 months: 17 of 74 (23.0%) patients were on inappropriate antibiotics. Our recommendations were well received. Reviewing C difficile-infected patients allowed for identification of opportunities to improve antibiotic utilization and potentially improved patient outcomes.

A multidisciplinary intervention to reduce antibiotic duration in lower respiratory tract infections

OBJECTIVES

Prolonged antibiotic courses are common in patients with lower respiratory tract infections (LRTIs) and contribute to antibiotic resistance and side effects. This study describes a multidisciplinary intervention to reduce antibiotic duration in LRTI patients.

METHODS

This was a prospective before-and-after intervention study conducted from November 2011 to December 2012. Antibiotic duration was recorded for 6 months for all LRTI admissions (pneumonia, exacerbation of chronic obstructive pulmonary disease, exacerbation of asthma, and other LRTIs), followed by the introduction of an intervention intended to reduce the duration of antibiotic treatment. The intervention incorporated an antibiotic duration based on the CURB65 score, automatic stop dates and pharmacist feedback to prescribers.

RESULTS

Two hundred and eighty-one patients were included in the pre-intervention group and 221 in the post-intervention group. The intervention resulted in a reduction in the duration of antibiotic treatment from 8.3 to 6.8 days (P < 0.001, 18.1% relative reduction). The rate of antibiotic-related adverse effects reduced from 31% to 19% (P = 0.03, 39.3% relative reduction). There was no increase in mortality or length of stay

CONCLUSIONS

A simple intervention can significantly reduce antibiotic duration and antibiotic-related side effects.

Pneumonia in low and middle income countries: progress and challenges

Pneumonia remains the leading cause of childhood mortality and the most common reason for adult hospitalisation in low and middle income countries, despite advances in preventative and management strategies. In the last decade, pneumonia mortality in children has fallen to approximately 1.3 million cases in 2011, with most deaths occurring in low income countries. Important recent advances include more widespread implementation of protein-polysaccharide conjugate vaccines against Haemophilus influenzae type B and Streptococcus pneumoniae, implementation of case-management algorithms and better prevention and treatment of HIV. Determining the aetiology of pneumonia is challenging in the absence of reliable diagnostic tests. High uptake of new bacterial conjugate vaccines may impact on pneumonia burden, aetiology and empiric therapy but implementation in immunisation programmes in many low and middle income countries remains an obstacle. Widespread implementation of currently effective preventative and management strategies for pneumonia remains challenging in many low and middle income countries.

Procalcitonin, pyuria and proadrenomedullin in the management of urinary tract infections--'triple p in uti': study protocol for a randomized controlled trial

Background

Urinary tract infections (UTIs) are among the most common infectious diseases and drivers of antibiotic use and in-hospital days. A reduction of antibiotic use potentially lowers the risk of antibiotic resistance. An early and adequate risk assessment combining medical, biopsychosocial and functional risk scores has the potential to optimize site-of-care decisions and thus allocation of limited health-care resources. The aim of this factorial design study is twofold: first, for Intervention A, it investigates antibiotic exposure of patients treated with a protocol based on the type of UTI, procalcitonin (PCT) and pyuria. Second, for Intervention B, it investigates the usefulness of the prognostic biomarker proadrenomedullin (ProADM) integrated into an interdisciplinary assessment bundle for site-of-care decisions.

Methods and design

This randomized controlled open-label trial has a factorial design (2 × 2). Randomization of patients will be based on a pre-specified computer-generated randomization list and independent for the two interventions. Adults with UTI presenting to the emergency department (ED) will be screened and enrolled after providing informed consent.

For our first Intervention (A), we developed a protocol based on previous observational research to recommend initiation and duration of antibiotic use based on the clinical presentation of UTI, pyuria and PCT levels. For our second intervention (B), an algorithm was developed to support site-of care decisions based on the prognostic marker ProADM and distinct nursing factors on days 1 and 3. Both interventions will be compared with a control group conforming to the guidelines.

The primary endpoints for the two interventions will be: (A) overall exposure to antibiotics and (B) length of physician-led hospitalization within a follow-up of 30 days. Endpoints are assessed at discharge from hospital, and 30 and 90 days after admission. We plan to screen 300 patients and enroll 250 for an anticipated estimated loss of follow-up of 20%. This will provide adequate power for the two interventions.

Discussion

This trial investigates two strategies for improved individualized medical care in patients with UTI. The minimally effective duration of antibiotic therapy is not known for UTIs, which is important for reducing the selection pressure for antibiotic resistance, costs and drug-related side effects. Triage decisions must be improved to reflect the true medical, biopsychosocial and functional risks in order to allocate patients to the most appropriate care setting and reduce hospital-acquired disability.

Trial registration

Trial registration number: ISRCTN13663741

Time to first antibiotics for pneumonia is not associated with in-hospital mortality

BACKGROUND

Time to first antibiotic (TTFA) is postulated to impact pneumonia mortality. The Joint Commission/Centers for Medicare and Medicaid Services national quality standards previously indicated that TTFA should be <6 h (modified from <4 h when the study was initiated, now eliminated as a time measure entirely).

OBJECTIVE

The purpose of this article was to determine whether TTFA is associated with inpatient mortality.

METHODS

The records of 444 consecutive patients admitted with pneumonia at a single institution were retrospectively reviewed for a correlation between TTFA and inpatient complications, including death. Statistical significance was set at p < 0.01 due to multiple comparisons.

RESULTS

Patients whose TTFA was <4 h had more complications (27% vs. 3%; p < 0.01) including death, intensive care unit admission, and intubation. These patients were judged sicker on arrival (median Emergency Severity Index 2 vs. 3; p < 0.001) and were more likely to be triaged to a critical care bed (36% vs. 5%; p < 0.001). Shortness of breath was the only presenting factor that was more frequent in the TTFA <4-h group (61% vs. 16%; p < 0.01).

CONCLUSIONS

Shorter TTFA is not associated with improved inpatient mortality. TTFA should not be considered to be a marker of quality of care but rather a reflection of patient disease severity.

The potential impact of biomarker-guided triage decisions for patients with urinary tract infections

OBJECTIVES

Current guidelines provide limited evidence as to which patients with urinary tract infection (UTI) require hospitalisation. We evaluated the currently used triage routine and tested whether a set of criteria including biomarkers like proadrenomedullin (proADM) and urea have the potential to improve triage decisions.

METHODS

Consecutive adults with UTI presenting to our emergency department (ED) were recruited and followed for 30 days. We defined three virtual triage algorithms, which included either guideline-based clinical criteria, optimised admission proADM or urea levels in addition to a set of clinical criteria. We compared actual treatment sites and observed adverse events based on the physician judgment with the proportion of patients assigned to treatment sites according to the three virtual algorithms. Adverse outcome was defined as transfer to the intensive care unit (ICU), death, recurrence of UTI or rehospitalisation for any reason.

RESULTS

We recruited 127 patients (age 61.8 ± 20.8 years; 73.2 % females) and analysed the data of 123 patients with a final diagnosis of UTI. Of these 123 patients, 27 (22.0 %) were treated as outpatients. Virtual triage based only on clinical signs would have treated only 22 (17.9 %) patients as outpatients, with higher proportions of outpatients equally in both biomarker groups (29.3 %; p = 0.02). There were no significant differences in adverse events between outpatients according to the clinical (4.5 %), proADM (2.8 %) or urea groups (2.8 %). The mean length of stay was 6.6 days, including 2.2 days after reaching medical stability.

CONCLUSIONS

Adding biomarkers to clinical criteria has the potential to improve risk-based triage without impairing safety. Current rates of admission and length of stay could be shortened in patients with UTI.

Biomarker-enhanced triage in respiratory infections: a proof-of-concept feasibility trial

Concerns about inadequate performance and complexity limit routine use of clinical risk scores in lower respiratory tract infections. Our aim was to study feasibility and effects of adding the biomarker proadrenomedullin (proADM) to the confusion, urea >7 mmol·L⁻¹, respiratory rate ≥30 breaths·min⁻¹, blood pressure <90 mmHg (systolic) or ≤60 mmHg (diastolic), age ≥65 years (CURB-65) score on triage decisions and length of stay.

In a randomised controlled proof-of-concept intervention trial, triage and discharge decisions were made for adults with lower respiratory tract infection according to interprofessional assessment using medical and nursing risk scores either without (control group) or with (proADM group) knowledge of proADM values, measured on admission, and on days 3 and 6. An adjusted generalised linear model was calculated to investigate the effect of our intervention.

On initial presentation the algorithms were overruled in 123 (39.3%) of the cases. Mean length of stay tended to be shorter in the proADM (n=154, 6.3 days) compared with the control group (n=159, 6.8 days; adjusted regression coefficient -0.19, 95% CI -0.41–0.04; p=0.1). This trend was robust in subgroup analyses and for overall length of stay within 90 days (7.2 versus 7.9 days; adjusted regression coefficient -0.18, 95% CI -0.40–0.05; p=0.13). There were no differences in adverse outcomes or readmission.

Logistic obstacles and overruling are major challenges to implement biomarker-enhanced algorithms in clinical settings and need to be addressed to shorten length of stay.

Proof-of-concept trial: how to shorten LOS in patients with LRTIs by reducing medically unnecessary days in the hospitalhttp://ow.ly/nI7z4

Can we use severity assessment tools to increase outpatient management of community-acquired pneumonia?

Outpatient management of community-acquired pneumonia (CAP) has several potential advantages, including significant cost-savings, a reduction in hospital-acquired infections and increased patient satisfaction. Despite the benefits, it is often difficult to identify which patients may be managed in the community without compromising patient safety. CAP severity scores, such as the pneumonia severity index (PSI) and the British Thoracic Society CURB65/CRB65 scores are designed to identify groups of patients at low risk of mortality who may be suitable for outpatient care. This review discusses the strengths and weaknesses of severity scores for use in determining site of care for patients with pneumonia. Use of the PSI in emergency departments has been shown to increase the proportion of patients treated in the community without increasing patient mortality or hospital readmissions. The CURB65 and CRB65 scores are less complex alternatives to the PSI that have been shown to perform similarly for prediction of 30-day mortality. All 3 scores identify populations at low risk of mortality who may be eligible for outpatient care. Nevertheless, a number of factors not included in severity scores may prevent discharge of these patients, including social factors, co-morbidities and severity markers not captured by severity scores. The limitations of severity scores are discussed along with recent attempts to improve predictive tools, with the development of new biomarkers and alternative scoring systems.

Synthesis of antifungal glucan synthase inhibitors from enfumafungin

An efficient, new, and scalable semisynthesis of glucan synthase inhibitors 1 and 2 from the fermentation product enfumafungin 3 is described. The highlights of the synthesis include a high-yielding ether bond-forming reaction between a bulky sulfamidate 17 and alcohol 4 and a remarkably chemoselective, improved palladium(II)-mediated Corey-Yu allylic oxidation at the highly congested C-12 position of the enfumafungin core. Multi-hundred gram quantities of the target drug candidates 1 and 2 were prepared, in 12 linear steps with 25% isolated yield and 13 linear steps with 22% isolated yield, respectively.

Seven-day antibiotic courses have similar efficacy to prolonged courses in severe community-acquired pneumonia--a propensity-adjusted analysis

There are no studies to guide the optimal duration of therapy in severe community-acquired pneumonia (CAP). The aim of this study was to determine whether 7 days of antibiotic treatment is equivalent to longer-course therapy in severe CAP. In this prospective observational study, we included patients with severe CAP (CURB65 score 3-5) admitted to the hospital with signs and symptoms consistent with pneumonia. A propensity score, derived through multiple logistic regression, was used to match patients into two groups: treated for 7 days vs. treated for >7 days. Patients who died, were admitted to the intensive-care unit, developed complicated pneumonia, failed to reach clinical stability or had positive cultures for microorganisms requiring prolonged treatment within the first 7 days were excluded. Patients outside the mutual range of the propensity score were also excluded. The primary outcome of this study was 30-day mortality. Secondary outcomes were subsequent requirement for mechanical ventilation and/or inotropic support and the development of complicated pneumonia or re-admission within 30 days. Four hundred and twelve patients were suitable for derivation of the propensity score. After matching on propensity score, 164 patients treated for 7 days were compared with 164 treated for >7 days; they were well matched in terms of age, gender, comorbidities, and physiological parameters. The results showed no significant differences in the primary and the secondary outcomes between the two groups. This study therefore suggests that, in the majority of severe CAP patients who have clinically responded, antibiotics can be safely discontinued at 7 days.

Bacteriological aetiology and antimicrobial treatment of pleural empyema

BACKGROUND

Our aims were to describe the aetiologies of culture-positive pleural infections and to evaluate the choice of empiric antimicrobial treatment regimens according to antimicrobial sensitivity, and to evaluate the possible influence of this on outcome.

METHODS

All cases over a 9-y period were identified from 3 hospitals using the laboratory databases of the clinical microbiology departments, and were verified by evaluating the medical records.

RESULTS

We identified 291 isolates in pleural fluid cultures from 158 patients. These included viridans streptococci (25%), Staphylococcus aureus (18%), anaerobic bacteria (17%), Enterobacteriaceae (12%), Staphylococcus epidermidis (10%), and Streptococcus pneumoniae (7%), with differences between nosocomial and community-acquired infections. The mortality (overall 27%) was highest among the patients with Enterobacteriaceae (50%) and S. aureus (36%) infections, and in patients with mixed infections (34%). The actual empiric treatment or the recommended penicillin plus metronidazole had low antimicrobial coverage (49%) compared to the proposed cefuroxime plus metronidazole (78%). Thoracentesis was often delayed (median 2 days). The adequacy of empiric antimicrobial therapy was independently correlated with mortality (odds ratio 0.43, 95% confidence interval 0.30-0.62).

CONCLUSIONS

The early diagnosis of pleural infection could be optimized. In this North-European patient population, we suggest that the recommended empiric antimicrobial treatment be changed to cefuroxime plus metronidazole for community-acquired and nosocomial infections.

Impact of different empirical antibiotic treatment regimens for community-acquired pneumonia on the emergence of Clostridium difficile

BACKGROUND

Treatment of community-acquired pneumonia (CAP) with newer fluoroquinolones may contribute to selection for Clostridium difficile. We studied the prevalence of C. difficile carriage and C. difficile infection (CDI) on admission, and nosocomial acquisition rates in patients hospitalized for CAP and compared different empirical treatment strategies.

METHODS

In a prospective study among patients admitted for antibiotic treatment of CAP, consecutive stool and skin samples were collected and cultured for C. difficile. Cultured isolates were typed by PCR ribotyping and characterized for toxinogenicity.

RESULTS

In total, 20 of 107 (18.7%) patients included carried C. difficile. Various ribotypes were found and 14 (70%) isolates were toxinogenic. On admission, prevalence of C. difficile carriage was 9.4% (n=9), of which 22% also carried C. difficile on the skin and one patient had mild CDI with persistent positive cultures. The overall nosocomial acquisition rate of C. difficile carriage was 11.2%. No nosocomially acquired CDI occurred. Acquisition rates of C. difficile were 11.9% (5/45) in moxifloxacin-, 11.1% (5/47) in β-lactam- and 9.0% (1/14) in β-lactam plus macrolide- or fluoroquinolone-treated patients (P=0.84). Risk factors for C. difficile carriage were intravenous antibiotic treatment >7 days [odds ratio (OR) 3.89; 95% confidence interval (CI) 1.30 to 11.79] and hospitalization during the past 3 months (OR 4.08; 95% CI 1.40 to 11.90).

CONCLUSIONS

In a non-outbreak setting with a low endemic rate, the prevalence of C. difficile carriage in patients admitted because of CAP is high and nosocomial acquisition rates for C. difficile colonization are 11%. Fluoroquinolones were not associated with increased acquisition rates for C. difficile as compared with other empirical regimens for CAP.