Guideline-Concordant Antimicrobial Therapy for Healthcare-Associated Pneumonia: A Systematic Review and Meta-analysis

Efficacy and validity of guideline-concordant treatment according to the JRS guidelines for the managements of pneumonia in adults updated in 2017 for nursing and healthcare-associated pneumonia. A propensity-matching score analysis

INTRODUCTION

Patients with nursing and healthcare-associated pneumonia (NHCAP) commonly receive empiric antibiotic therapy according to the guideline's recommendation corresponding to the patient's deteriorated conditions. However, it is unclear whether guideline-concordant treatment (GCT) could be effective or not.

PATIENTS AND METHODS

To evaluate the efficacy and validity of GCT according to the current guideline for pneumonia, we conducted this retrospective study. NHCAP patients who were admitted to our institute between 2014 and 2017 were enrolled. Based on the initial antibiotic treatment, these patients were divided into two groups, the GCT group (n = 83) and the non-GCT group (n = 146). Propensity score matching (PSM) was used to balance the baseline characteristics and potential confounders between the two groups. After PSM, patients' characteristics, microbial profiles, and clinical outcomes were evaluated.

RESULTS

Both groups were well-balanced after PSM, and 78 patients were selected from each group. There were no differences in patients' characteristics or microbial profiles between the two groups. As for outcomes, there were no differences in 30-day, in-hospital mortality rate, duration of antibiotic treatment, or admission. The severity of pneumonia was more severe in patients with the GCT group than those with the non-GCT group. Anti-pseudomonal agents as initial treatment were more frequently seen in patients with the GCT group than those in the non-GCT group.

CONCLUSION

Unlike previous studies, GCT's recommendation for management of pneumonia by the JRS in 2017 would appear to be valid and does not increase the mortality rate.

Identification of hospitalized patients with community-acquired infection in whom treatment guidelines do not apply: a validated model

OBJECTIVES

To develop and validate a clinical model to identify patients admitted to hospital with community-acquired infection (CAI) caused by pathogens resistant to antimicrobials recommended in current CAI treatment guidelines.

METHODS

International prospective cohort study of consecutive patients admitted with bacterial infection. Logistic regression was used to associate risk factors with infection by a resistant organism. The final model was validated in an independent cohort.

RESULTS

There were 527 patients in the derivation and 89 in the validation cohort. Independent risk factors identified were: atherosclerosis with functional impairment (Karnofsky index <70) [adjusted OR (aOR) (95% CI) = 2.19 (1.41-3.40)]; previous invasive procedures [adjusted OR (95% CI) = 1.98 (1.28-3.05)]; previous colonization with an MDR organism (MDRO) [aOR (95% CI) = 2.67 (1.48-4.81)]; and previous antimicrobial therapy [aOR (95% CI) = 2.81 (1.81-4.38)]. The area under the receiver operating characteristics (AU-ROC) curve (95% CI) for the final model was 0.75 (0.70-0.79). For a predicted probability ≥22% the sensitivity of the model was 82%, with a negative predictive value of 85%. In the validation cohort the sensitivity of the model was 96%. Using this model, unnecessary broad-spectrum therapy would be recommended in 30% of cases whereas undertreatment would occur in only 6% of cases.

CONCLUSIONS

For patients hospitalized with CAI and none of the following risk factors: atherosclerosis with functional impairment; previous invasive procedures; antimicrobial therapy; or MDRO colonization, CAI guidelines can safely be applied. Whereas, for those with some of these risk factors, particularly if more than one, alternative antimicrobial regimens should be considered.

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.

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

BACKGROUND

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

OBJECTIVE

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

SOURCES

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

CONTENT

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

IMPLICATIONS

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

Short-course versus long-course therapy of the same antibiotic for community-acquired pneumonia in adolescent and adult outpatients

BACKGROUND

Community-acquired pneumonia (CAP) is a lung infection that can be acquired during day-to-day activities in the community (not while receiving care in a hospital). Community-acquired pneumonia poses a significant public health burden in terms of mortality, morbidity, and costs. Shorter antibiotic courses for CAP may limit treatment costs and adverse effects, but the optimal duration of antibiotic treatment is uncertain.

OBJECTIVES

To evaluate the efficacy and safety of short-course versus longer-course treatment with the same antibiotic at the same daily dosage for CAP in non-hospitalised adolescents and adults (outpatients). We planned to investigate non-inferiority of short-course versus longer-term course treatment for efficacy outcomes, and superiority of short-course treatment for safety outcomes.

SEARCH METHODS

We searched CENTRAL, which contains the Cochrane Acute Respiratory Infections Group Specialised Register, MEDLINE, Embase, five other databases, and three trials registers on 28 September 2017 together with conference proceedings, reference checking, and contact with experts and pharmaceutical companies.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing short- and long-courses of the same antibiotic for CAP in adolescent and adult outpatients.

DATA COLLECTION AND ANALYSIS

We planned to use standard Cochrane methods.

MAIN RESULTS

Our searches identified 5260 records. We did not identify any RCTs that compared short- and longer-courses of the same antibiotic for the treatment of adolescents and adult outpatients with CAP.We excluded two RCTs that compared short courses (five compared to seven days) of the same antibiotic at the same daily dose because they evaluated antibiotics (gemifloxacin and telithromycin) not commonly used in practice for the treatment of CAP. In particular, gemifloxacin is no longer approved for the treatment of mild-to-moderate CAP due to its questionable risk-benefit balance, and reported adverse effects. Moreover, the safety profile of telithromycin is also cause for concern.We found one ongoing study that we will assess for inclusion in future updates of the review.

AUTHORS' CONCLUSIONS

We found no eligible RCTs that studied a short-course of antibiotic compared to a longer-course (with the same antibiotic at the same daily dosage) for CAP in adolescent and adult outpatients. The effects of antibiotic therapy duration for CAP in adolescent and adult outpatients remains unclear.

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.

Clinical evaluation of the need for carbapenems to treat community-acquired and healthcare-associated pneumonia

Carbapenems have an overall broad antibacterial spectrum and should be protected against from the acquisition of drug resistance. The clinical advantages of carbapenem in cases of pneumonia have not been certified and the need for antipseudomonal antimicrobial agents to treat healthcare-associated pneumonia (HCAP) remains controversial. We introduced an antimicrobial stewardship program for carbapenem and tazobactam/piperacillin use and investigated the effects of this program on the clinical outcomes of 591 pneumonia cases that did not require intensive care unit management, mechanical ventilation or treatment with vasopressor agents [221 patients with community-acquired pneumonia (CAP) and 370 patients with HCAP]. Compared with the pre-intervention period, age, comorbidities and the severity and etiology of pneumonia did not differ during the intervention period. Carbapenems were rarely used during the intervention period in cases of pneumonia (CAP: 12% vs. 1%, HCAP: 13% vs. 1%), while antipseudomonal beta-lactam use was reduced from 33% to 8% among cases with HCAP. This reduction in the rate of carbapenem administration did not have an impact on the prognosis in the cases of CAP, and the in-hospital mortality was lower among the patients with HCAP during the intervention period (15% vs. 5%, p = 0.013). The causes of death in the cases of HCAP were not directly related to pneumonia during the intervention period. The current study shows that carbapenem use can be avoided in cases of CAP or HCAP that are not in a critical condition. The frequent use of antipseudomonal beta-lactams does not improve the clinical outcomes of HCAP.

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

OBJECTIVES

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.

PATIENTS AND METHODS

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.

RESULTS

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.

CONCLUSIONS

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.

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.