Healthcare-associated Pneumonia Criteria Research Articles

Risk factors for community-onset pneumonia caused by drug-resistant pathogens: A prospective cohort study

Introduction: There is no consensual definition of risk factors for drug resistant pathogens (DRP) in community-onset pneumonia (COP). Healthcare-associated pneumonia criteria have been abandoned because they were found to have weak discriminative power. Our aim was to identify risk factors for DRP in COP. Methods: Prospective cohort study, conducted over a two years’ period, in a community-based hospital, including all adult patients with COP criteria. Univariate and multivariate logistic regression modeling were performed to understand the association of risk factors (demographic, clinical and epidemiological) with COP by a DRP (PES: Pseudomonas aeruginosa, extended-spectrum ß-lactamase producing Enterobacteriaceae, Methicillin-resistant Staphylococcus aureus; and other non-fermenting gram-negative bacteria, namely Acinetobacter baumannii). Results: A total of 660 cases of COP were included, with a mean (±SD) age of 74±15 years and 58.9% of males. Microbiological documentation was possible in 32.6% of the cases. There were 197 cases selected for further analysis, of which 37 were cases of PES. The multivariate logistic regression model retained antibiotic use in the previous 90 days (adjusted OR=4.411, 95%CI [1.745-11.148]) and being bed-ridden (adjusted OR=5.492, 95%CI [2.121-14.222]), adjusted for Charlson's Index, CURB 65 and provenience from a long-term care facility. The area under the ROC curve for this model was 0.832, 95%CI [0.756-0.908], higher than the application of the HCAP criteria (AUROC = 0.676, 95%CI [0.582-0.770]). Conclusion: In this study, antibiotic use in the previous 90 days and being bed-ridden were independently associated with COP caused by DRP, after adjustment for Charlson's Index, CURB 65 and provenience from a long-term care facility.

1482. Local validation of the drug resistance in pneumonia clinical prediction score at a large academic medical center and a community hospital

BackgroundCommunity-acquired pneumonia (CAP) is responsible for ~1 million emergency department (ED) visits yearly and the leading cause of infection-related deaths. Given that increasing antibiotic resistance rates complicate appropriate empiric antibiotic selection, clinicians may benefit from tools to help identify patients at risk for drug-resistant pathogens (DRPs). Limitations of traditional tools, such as healthcare-associated pneumonia criteria (HCAP), have led to development of novel scoring tools such as the drug resistance in pneumonia (DRIP) score. Webb et al. showed the DRIP score was more predictive of CAP caused by DRPs than HCAP criteria. The objective of this study was to validate the DRIP score in a local population of hospitalized patients at an academic and a community medical center.MethodsPatients who presented to the ED between May 2017 and May 2019 were included in this retrospective review. Patients were included if they were ≥ 18 years diagnosed with CAP by radiographic evidence with respiratory culture positivity and susceptibility results. Exclusion criteria were: presence of non-bacterial non-respiratory pathogens, patients with cystic fibrosis, lung transplant or systemic co-infections. The primary outcome was validation of the DRIP score by comparing the sensitivity, specificity, negative and positive predictive values (NPV/PPV) to the derivation and validation study by Webb et al. Secondary outcomes were the percentage of CAP cases with DRPs and the predictability of DRP using the DRIP score versus HCAP criteria.ResultsA total of 164 patients were included; 60.4% were male with a median age of 70 years. The primary outcome shown in Table 1 demonstrated similar sensitivity, specificity, NPV, and PPV of the DRIP score to those in the study by Webb et al. Staphylococcus aureus (32.9%) and Streptococcus pneumoniae (27.4%) were the most commonly isolated pathogens and CAP due to DRPs occurred in 30.5% of patients. The DRIP score also demonstrated improved performance in predicting DRPs in CAP compared to the HCAP Criteria as shown in Table 2.Table 1. DRIP Score Validation Table 2. Predictability of the DRIP score vs. HCAP criteria ConclusionOur results further validate the DRIP score derived by Webb et al. in predicting DRPs in CAP. These results encourage a local prospective evaluation of the DRIP score as an antimicrobial stewardship tool.Disclosures All Authors: No reported disclosures

Validation of the Drip Score at A Community-Teaching Hospital

Rationale Recent data suggest that health care–associated pneumonia (HCAP) criteria has poor predictive value in determining risk for drug-resistant pathogens (DRPs) and leads to increased use of broad-spectrum antibiotics. The Drug Resistance in Pneumonia (DRIP) Score highlights a selective set of criteria to predict pneumonia risk. Validation studies show conflicting results on the impact of antibiotic selection based on the DRIP score. Methods This was a retrospective chart review of hospitalized patients from March 2018 to April 2018 who were started on antibiotics for a respiratory tract infection. The HCAP criteria and DRIP scores were calculated and antibiotic selection was analyzed. The primary focus was to determine if utilization of the DRIP score could modify antipseudomonal beta-lactam (APBL) prescribing patterns. Results A total of 82 patients were included in the study. Sixty-four (78%) patients had a DRIP score <4 with 19 (30%) receiving an APBL. There were 18 patients with a DRIP score >4, and 7 (39%) patients received non-APBL antibiotics. The HCAP criteria and subsequent prescribing was also analyzed. Forty-nine patients were identified as not meeting HCAP criteria. Of these patients, 12 (24%) received APBL. Thirty-three patients met HCAP criteria, and 15 (45%) received a non-APBL. If HCAP criteria were used to guide antibiotic prescribing, we would see a net increase of 3% in APBL use; whereas if DRIP scores were implemented, we would see a net decrease of 14% in APBL use. Conclusions Our study indicates that implementation of the DRIP score would result in decreased empiric APBL use.

Strategies for prediction of drug-resistant pathogens and empiric antibiotic selection in community-acquired pneumonia

Although most patients with community-acquired pneumonia (CAP) are appropriately treated with narrow-spectrum antibiotics, predicting which patients require coverage of drug-resistant pathogens (DRP) remains a challenge. The 2019 American Thoracic Society/Infectious Diseases Society of America CAP guidelines endorse using locally validated prediction models for DRP. Here we review risk factors for DRP and provide a summary of available risk prediction models. Both inadequate initial empiric spectrum as well as unnecessary broad-spectrum antibiotic use are associated with poor outcomes in CAP. Multiple prediction models for DRP-based patient-level risk factors have been published, with some variation in included predictor variables and test performance characteristics. Seven models have been robustly externally validated, and implementation data have been published for two of these models. All models demonstrated better performance than the healthcare-associated pneumonia criteria, with most favoring sensitivity over specificity. We also report validation of the novel, risk factor-based treatment algorithm proposed in the American Thoracic Society/Infectious Diseases Society of America guidelines which strongly favors specificity over sensitivity, especially in nonsevere pneumonia. Using patient-level risk factors to guide the decision whether to prescribe broad-spectrum antibiotics is a rational approach to treatment. Several viable candidate prediction models are available. Hospitals should evaluate the local performance of existing scores before implementing in routine clinical practice.

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

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). We conducted a quasi-experimental, pre-post implementation study of ePNa with DRIP score (2015) vsePNa 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. 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. Electronic calculation of the DRIP score was more effective than HCAP criteria for guiding appropriate broad-spectrum antibiotic use in community-onset pneumonia.

Treatment Trends and Outcomes in Healthcare-Associated Pneumonia.

The American Thoracic Society and Infectious Diseases Society of America guidelines for management of healthcare-associated pneumonia (HCAP), first published in 2005, have been controversial regarding the selection of empiric broad-spectrum antibiotics, whether the criteria for HCAP predicts the likelihood of infection with multidrug resistant organisms, and whether HCAP patients have improved outcomes when treated with empiric broad-spectrum antibiotics. A retrospective cohort study at 488 US hospitals from July 2007 to November 2011. Patients who met criteria for HCAP were included. Guideline-concordant antibiotics were assessed based on guideline recommendations. We assessed changes in hospital rates of concordant antibiotic use over time and their correlation with outcomes. Among 149,963 patients with HCAP, 19.6% received fully guideline-concordant antibiotics, 21.7% received partially concordant antibiotics, and 58.9% received discordant antibiotics. Guideline concordance increased over time. Rates of fully or partially concordant antibiotics varied across hospitals (median 36.4%; interquartile range 25.8%-49.1%). Among patients who received discordant antibiotics, 81.5% were treated according to community-acquired pneumonia (CAP) guidelines. On average, the rate of guideline concordance increased by 2.2% per 6-month interval, while hospital level rates of mortality, excess length of stay, and progression to respiratory failure did not change. In this large, nationally representative cohort, only 1 in 5 patients with risk factors for HCAP received treatment that was fully in accordance with guidelines, and many received CAP therapy instead. At the hospital level, increases in the use of concordant antibiotics were not associated with declines in mortality, excess length of stay, or progression to respiratory failure.

Türkiye'de sağlık bakımı ile ilişkili pnömoni olgularının klinik özellikleri ve sonuçları

Pneumonia in cases with preceding hospitalization, hemodialysis, intravenous therapy, wound care, or chemotherapy within the prior 30 days and residence in nursing homes are defined as healthcare associated pneumonia (HCAP). The aim of this study was to compare the demographic and laboratory data, isolated causative agents and prognosis of patients with community-acquired pneumonia (CAP) and HCAP in a large population in Turkey. The data of 785 cases (average age 65.3 ± 16.4, 530 male) registered to Turkish Thoracic Society Respiratory Infections Study Group CAP database (TURCAP) were examined. The demographic data, clinical history, pneumonia severity scores (PSI), laboratory and radiologic findings of the CAP and HCAP patients were compared. Out of 785 cases, 207 (26.4%) were diagnosed with HCAP and 578 (73.6%) with CAP. Among HCAP cases, 140/207 (67.6%) had preceding hospitalization in the last 90 days, 28/207 (13.5%) were on a hemodialysis program during the previous 30 days and 22/207 (10.6%) were staying in nursing homes. Patients with HCAP more frequently had comorbidities (93.2% vs. 81.6%; p= 0.001) and higher PSI scores (103.9 ± 37.2 vs. 94.6 ± 35.4; p= 0.002) compared to patients with CAP. A causative microorganism was isolated in only 12.1% (70/578) of CAP and 14.5% (30/207) of HCAP patients. The length of stay in hospital was higher in HCAP than CAP (8.6 ± 5.5 vs. 7.5 ± 6.1 days, p= 0.03); however the rates of treatment failure, intensive care unit admission and mortality were similar. In comparison to CAP, HCAP patients tend to have more severe disease, despite have no difference in mortality. The current criteria for HCAP do not predict worse clinical outcomes. Further work is required to define local risk factors for multidrug-resistant pathogens.

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.

Impact of the Joint Commission Pneumonia Core Measure on Antibiotic Use and Selection for Community-Acquired Pneumonia in the Emergency Room.

Prior to 2012, The Joint Commission (TJC) pneumonia core measure (PN-5) required antibiotic administration for suspected community-acquired pneumonia (CAP) within 6 hours of arrival to the emergency room (ER). In 2012, TJC issued PN-6 requiring antibiotic administration within 24 hours of presentation. Though PN-6 was anticipated to reduce overuse and inappropriate antibiotic use and improve appropriate antibiotic selection, the impact of PN-5 and PN-6 on optimizing care for CAP in the ER remains unknown. To investigate the impact of TJC pneumonia core measures on antibiotic use in the ER for suspected CAP. In this single-center study, medical records of patients 18 years old and older diagnosed with CAP in the ER during 2011 (PN-5) and 2012 (PN-6) and admitted for 1 day or longer were reviewed. Exclusion criteria included criteria for health care-associated pneumonia. Comparisons between groups were performed using descriptive statistics and contingency table analysis with chi-square or Fisher exact tests for categorical variables and t tests for continuous variables. Statistical analyses were performed using Microsoft Excel 2010 and SAS version 9.4. Antibiotic use was comparable between PN-5 and PN-6. Approximately half of patients in each group received an appropriate empiric CAP regimen (52% vs 54%; P = .807). Among inappropriate regimens, the most common reason was use of a beta-lactam alone (69% vs 83%; P = .26). More patients had an ultimate diagnosis of CAP with PN-6 (78% vs 86%; P = .3). Changes in pneumonia core measure requirements did not have a significant impact on appropriate antibiotic use in the ER.

Comparison of clinical prediction models for resistant bacteria in community-onset pneumonia.

Six recently published algorithms classify pneumonia patients presenting from the community into high- and low-risk groups for resistant bacteria. Our objective was to compare performance of these algorithms for identifying patients infected with bacteria resistant to traditional community-acquired pneumonia antibiotics. This was a retrospective study of consecutive adult patients diagnosed with pneumonia in an emergency department and subsequently hospitalized. Each patient was classified as high or low risk for resistant bacteria according to the following algorithms: original health care-associated pneumonia (HCAP) criteria, Summit criteria, Brito and Niederman strategy, Shorr model, Aliberti model, and Shindo model. The reference for comparison was detection of resistant bacteria, defined as methicillin-resistant Staphylococcus aureus or Gram-negative bacteria resistant to ceftriaxone or levofloxacin. A total of 614 patients were studied, including 36 (5.9%) with resistant bacteria. The HCAP criteria classified 304 (49.5%) patients as high risk, with an area under the receiver operating characteristic curve (AUC) of 0.63 (95% confidence interval [CI]=0.54 to 0.72), sensitivity of 0.69 (95% CI=0.52 to 0.83), and specificity of 0.52 (95% CI=0.48 to 0.56). None of the other algorithms improved both sensitivity and specificity or significantly improved the AUC. Compared to the HCAP criteria, the Shorr and Aliberti models classified more patients as high risk, resulting in higher sensitivity and lower specificity. The Shindo model classified fewer patients as high risk, with lower sensitivity and higher specificity. All algorithms for identification of resistant bacteria included in this study had suboptimal performance to guide antibiotic selection. New strategies for selecting empirical antibiotics for community-onset pneumonia are necessary.

Association of guideline-based antimicrobial therapy and outcomes in healthcare-associated pneumonia.

Guidelines for treatment of healthcare-associated pneumonia (HCAP) recommend empirical therapy with broad-spectrum antimicrobials. Our objective was to examine the association between guideline-based therapy (GBT) and outcomes for patients with HCAP. We conducted a pharmacoepidemiological cohort study at 346 US hospitals. We included adults hospitalized between July 2007 and June 2010 for HCAP, defined as patients admitted from a nursing home, with end-stage renal disease or immunosuppression, or discharged from a hospital in the previous 90 days. Outcome measures included in-hospital mortality, length of stay and costs. Of 85 097 patients at 346 hospitals, 31 949 (37.5%) received GBT (one agent against MRSA and at least one against Pseudomonas). Compared with patients who received non-GBT, those who received GBT had a heavier burden of chronic disease and more severe pneumonia. GBT was associated with higher mortality (17.1% versus 7.7%, P < 0.001). Adjustment for demographics, comorbidities, propensity for treatment with GBT and initial severity of disease decreased, but did not eliminate, the association (OR 1.39, 95% CI 1.32-1.47). Using an adaptation of an instrumental variable analysis, GBT was not associated with higher mortality (OR 0.93, 95% CI 0.75-1.16). Adjusted length of stay and costs were also higher with GBT. Among patients who met HCAP criteria, GBT was not associated with lower adjusted mortality, length of stay or costs in any analyses. Better criteria are needed to identify patients at risk for MDR infections who might benefit from broad-spectrum antimicrobial coverage.

Outcomes of patients with healthcare-associated pneumonia: worse disease or sicker patients?

Healthcare-associated pneumonia (HCAP) is an entity distinct from community-acquired pneumonia (CAP). HCAP has a higher case-fatality rate, due either to HCAP organisms or to the health status of HCAP patients. The contribution of HCAP criteria to case-fatality rate is unknown. We conducted a retrospective review of adult patients admitted with a diagnosis of pneumonia from July 2007 through November 2011 to 491 US hospitals. HCAP was defined as having at least 1 of the following: prior hospitalization within 90 days, hemodialysis, admission from a skilled nursing facility, or immune suppression. We compared characteristics of patients with CAP and patients with HCAP and explored the contribution of HCAP criteria to case-fatality rate in a hierarchical generalized linear model. Of 436,483 patients hospitalized with pneumonia, 149,963 (34.4%) had HCAP. Compared to CAP patients, HCAP patients were older, had more comorbidities, and were more likely to require intensive care unit (ICU) care. In-hospital case-fatality rate was higher among patients with HCAP, compared to those with CAP (11.1% vs 5.1%, P < .001). After adjustment for demographics, comorbidities, presence of other infections, early ICU admission, chronic and acute medications, early tests and therapies, and length of stay, HCAP remained associated with increased case-fatality rate (odds ratio [OR], 1.35 [95% confidence interval (CI), 1.32-1.39]); odds of death increased for each additional HCAP criterion (OR [95% CI]: 1 criterion, 1.27 [1.23-1.31], 2 criteria, 1.55 [1.49-1.62], and 3 or more criteria, 1.88 [1.72-2.06]). After adjustment for differences in patient characteristics, HCAP was associated with greater case-fatality rate than CAP. This difference may be due to HCAP organisms or to HCAP criteria themselves.

A Critical Evaluation of Healthcare-Associated Pneumonia and the Need for Anti-pseudomonal Therapy, Including Double Coverage

In 2005, healthcare-associated pneumonia (HCAP) was described as a distinct entity, reflecting the concern that patients with HCAP have mortality rates and microbiologic culprits more akin to patients with hospital-acquired pneumonia (HAP) and, thus, warrant treatment similar to HAP, including empiric broad spectrum antibiotics. Increasing evidence suggests that the HCAP definition and criteria are insufficient predictors of which patients are at highest risk of being infected with a multi-drug resistant organism (MDRO); this lack of accuracy leads to overuse of broad spectrum antibiotics. New risk stratification schemes have been proposed that may supplant our current reliance on HCAP criteria for identifying patients who may be infected with an MDRO. Regardless of the risk stratification method used, antibiotic decisions must account for local MDRO prevalence rates. In settings where P. aeruginosa resistance to anti-pseudomonal therapies is high or in patients who are critically ill, empiric combination therapy for P. aeruginosa may be considered. However, therapy should be narrowed to a single agent once an effective agent has been identified from culture susceptibility data.

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 Outcome of Pneumonia Caused by Methicillin-Resistant Staphylococcus aureus (MRSA) in Canadian Hospitals

BackgroundMRSA remains a leading cause of hospital-acquired (HAP) and healthcare-associated pneumonia (HCAP). We describe the epidemiology and outcome of MRSA pneumonia in Canadian hospitals, and identify factors contributing to mortality.MethodsProspective surveillance for MRSA pneumonia in adults was done for one year (2011) in 11 Canadian hospitals. Standard criteria for MRSA HAP, HCAP, ventilator-associated pneumonia (VAP), and community-acquired pneumonia (CAP) were used to identify cases. MRSA isolates underwent antimicrobial susceptibility testing, and were characterized by pulsed-field gel electrophoresis (PFGE) and Panton-Valentine leukocidin (PVL) gene detection. The primary outcome was all-cause mortality at 30 days. A multivariable analysis was done to examine the association between various host and microbial factors and mortality.ResultsA total of 161 patients with MRSA pneumonia were identified: 90 (56%) with HAP, 26 (16%) HCAP, and 45 (28%) CAP; 23 (14%) patients had VAP. The mean (± SD) incidence of MRSA HAP was 0.32 (± 0.26) per 10,000 patient-days, and of MRSA VAP was 0.30 (± 0.5) per 1,000 ventilator-days. The 30-day all-cause mortality was 28.0%. In multivariable analysis, variables associated with mortality were the presence of multiorgan failure (OR 8.1; 95% CI 2.5-26.0), and infection with an isolate with reduced susceptibility to vancomycin (OR 2.5, 95% CI 1.0-6.3).ConclusionsMRSA pneumonia is associated with significant mortality. Severity of disease at presentation, and infection caused by an isolate with elevated MIC to vancomcyin are associated with increased mortality. Additional studies are required to better understand the impact of host and microbial variables on outcome.

Validation of a scoring tool to predict drug-resistant pathogens in hospitalised pneumonia patients

Health care-associated pneumonia (HCAP) affects a heterogeneous group of patients in frequent contact with health care systems. However, HCAP criteria poorly predict infection with drug-resistant (DR) pathogens. To validate our previously reported risk-scoring model (predictive of DR pathogen infection) in patients admitted to hospital with pneumonia. We evaluated 580 patients admitted with culture-positive bacterial pneumonia. We identified risk factors, evaluated the risk-scoring model's capacity to predict infection by DR pathogens and compared the model's diagnostic accuracy with that of current HCAP criteria. DR pathogens were observed in 227/580 patients (39.1%). Of 269 HCAP patients, 153 (56.9%) were infected with DR pathogens. Overtreatment was more common in HCAP than in community-acquired pneumonia (58.7% vs. 41.2%, P < 0.001). Recent hospitalisation, admission from a long-term care facility, recent antibiotic treatment and tube feeding were independently associated with DR pathogens. For pathogen prediction, the risk-scoring model showed better diagnostic accuracy than HCAP criteria (area under receiver operating-characteristic curve = 0.723 vs. 0.673, P < 0.001). According to current HCAP criteria, half of the HCAP patients were treated unnecessarily with broad-spectrum antibiotics. Risk scoring by stratifying risk factors could improve the identification of patients likely to be infected with DR pathogens.

Compliance with established pneumonia core measures at MD Anderson Cancer Center in the emergency center.

189 Background: Pneumonia is the major cause of death due to infectious diseases in the United States. In the cancer patient, pneumonia is the overall leading infectious cause of death. Pneumonia Core Measures (PCM) and Clinical Pathways are frequently used by healthcare organizations to ensure the delivery of high-quality care and pathogen-directed therapy. A multidisciplinary team was organized at the University of Texas MD Anderson Cancer Center (MDACC) Emergency Center (EC) into a Pneumonia Team to optimize care and to enhance compliance with current PCM. Methods: A retrospective review of EC patients during pneumonia season was completed. Results: Three areas for improvement in the EC were identified. The areas include lack of EC staff’s knowledge on PCM, lack of standardized order-sets for pathogen-directed treatment, and cancer patients presenting with pneumonia syndromes that fall outside established Community-Acquired Pneumonia (CAP) guidelines. The identified problems were addressed through three strategies: Intense EC staff education initially and yearly prior to pneumonia season (September-March). Microbiologic analysis of the pathogens responsible for the pneumonias in our unique cancer population at MDACC. Development and implementation of an institutional pneumonia algorithm and an order-set. The Pneumonia Team also identified a gap between our patient population and the current PCM. Pneumonia patients at MDACC EC are divided into two distinct groups, solid tumor and hematologic cancers. The microbiology analyzed in both groups is consistent with Healthcare-Associated Pneumonia (HCAP) and not CAP. Microbiology analysis identified gram positive, gram negative, fungal, viral and multi-drug resistant organisms. The initial analysis demonstrated that 87% of our patients met criteria for HCAP and only 12% met CAP. Based on this percentage, antibiotic selection for our CAP patients comprises a small portion of our total population. Conclusions: Our current algorithm and order-set optimize care and minimize variation to match our patient population. These findings provide important considerations for policy makers in regard to pneumonia measurements in a cancer setting.

Guideline-concordant antibiotic therapy and clinical outcomes in healthcare-associated pneumonia

The 2005 ATS/IDSA guidelines defined healthcare-associated pneumonia (HCAP) as a novel category of pneumonia in patients with significant healthcare exposure in whom the risk of drug resistant bacteria may be higher. In this study, we compare clinical outcomes in patients with HCAP who were treated with guideline-concordant antibiotic regimens with those who were not. Medical records of 100 patients meeting HCAP criteria admitted to an academic tertiary care hospital between January 2009 and January 2011 were retrospectively reviewed. Cases were divided into guideline-concordant and guideline-discordant groups based on antibiotic therapy. Demographic, microbiological and clinical outcome data were compared for both groups. Patients in this cohort had multiple co-morbidities, severe pneumonia (mean PSI score 124.1), and significant mortality (22%). 21 of the 100 cases (21.0%) were culture positive, of which 11 (53.8%) represented drug-resistant pathogens. No statistically significant differences for any of the four clinical outcome measures were detected between the guideline-concordant therapy group and guideline-discordant group. In multivariate regression analysis controlling for possible confounders, similar results were observed, with the exception that length of stay was significantly longer (3.99 days, p<0.001) in the discordant group. Three or more HCAP criteria (OR 10.89) and wound care (OR 6.32) were characteristics found to be associated with increased risk for drug-resistant pathogens. In our cohort, the HCAP model identified a population with significant co-morbidities and increased risk for drug-resistant pathogens, severe pneumonia, and increased mortality. However, clinical outcomes were not significantly improved with guideline-concordant antibiotic therapy.

Clinical Scoring for Risk of Resistant Organisms in Pneumonia: Right Idea, Wrong Interpretation

To the Editor—In their recent article, Shorr and colleagues present a new clinical tool to predict risk of drug-resistant bacterial pneumonia in patients presenting to emergency departments [1]. Improving risk assessment and minimizing inappropriate antibiotic use are necessary given the increasing prevalence of resistant pathogens and the risk of selecting for further resistance through overuse of broad-spectrum antibiotics, but this new risk score has several weaknesses. A weighted risk score is an attractive strategy to improve clinical decision making, but the authors overstate its advantages over the existing healthcare-associated pneumonia (HCAP) definition. Although the authors assert that their new risk score is superior to HCAP criteria because it incorporates weighting of risk factors, the cutoff of 0 turns the risk score into a dichotomous tool by which the presence of any risk factor yields a score considered positive rather than a stratified risk score. Under this conclusion, the predictive ability of the new tool is comparable (but not superior) to the current HCAP definition. Using a dichotomous risk tool ignores the information contained in a scoring system, and such a tool cannot be compared directly with the HCAP criteria. To compare the two, cutoff points should be contrasted for persons meeting 1, 2, or more HCAP or risk score criteria. The authors could further improve the predictive ability of their score by presenting likelihood ratios for each of the risk scores of the new tool. The authors present single positive and negative predictive values based on a risk score of 0, but these statistics could be calculated for other scores as well. Because of the effect of prevalence on the performance of diagnostic tests, we are concerned that the prevalence of drug-resistant pathogens reported in the study is inaccurate due to verification bias that occurs when the action of performing a test is affected by the pretest probability of disease [2]. The authors report a 47% prevalence of drug-resistant pathogens, likely an overestimation. A medical history suggesting a person had high risk for drug-resistant bacterial infection might influence physicians’ decisions to obtain cultures, a criterion for inclusion in the study. Persons without significant healthcare exposure might be deemed low-risk by clinicians, who would not order cultures, leading to underrepresentation of these patients in this study. Verification bias results in overestimation of the sensitivity and underestimation of the specificity of the new risk score. Unfortunately it is difficult to confirm that verification bias has occurred; however, the authors could have performed sensitivity analyses or controlled for culture collection to assess this problem. Finally, the most appropriate cutoff for risk score is determined by weighing the costs of further testing or broad-spectrum antibiotic use in patients who do not need them against benefits of appropriate early therapy in those infected with drug-resistant pathogens. This balance will depend on the clinical characteristics and risk factors of the patients, societal views of medical care, and economic considerations. Although the HCAP definition reaches an imperfect balance, the authors’ clinical risk score fails to improve upon that standard.

Poor prediction of potentially drug-resistant pathogens using current criteria of health care-associated pneumonia

Health care-associated pneumonia (HCAP) includes a broad range of patients having frequent or chronic contact with health care systems. However, the relationship between current defining criteria for HCAP and the risk of potentially drug-resistant (PDR) pathogens is controversial. We retrospectively evaluated patients admitted to Severance Hospital in South Korea with culture-positive pneumonia from January 2008 to December 2009. We analyzed the associations between risk factors for HCAP and infection with PDR pathogens, and developed a new scoring system to predict infection with PDR pathogens. Among 339 patients, PDR pathogens were observed in 122 (36.0%). PDR pathogens were more common in HCAP than community-acquired pneumonia (CAP) (48.5% versus 23.8%, P<0.001). In a logistic regression, prior hospitalization within 90 days of pneumonia (OR=2.51, P=0.003), recent treatment with antimicrobials (OR=2.35, P=0.039), and nasogastric tube feeding (OR=15.28, P<0.001) were independently associated with PDR pathogens. For the prediction of PDR pathogens, the sensitivity and specificity of current HCAP criteria were 66.4% and 60.4%, respectively, and 68.0% and 67.3%, respectively, for the new scoring system. Moreover, the new scoring system showed better diagnostic accuracy than current HCAP criteria (area under curve=0.711 versus 0.634, P<0.001). The current HCAP criteria are poor predictors of PDR pathogens and all patients with HCAP should not be empirically treated for these pathogens. To avoid excessive antibiotic use, individual risk stratification approaches should be considered.