Impact of bacteremia prediction rule in CAP: Before and after study

European society of clinical microbiology and infectious diseases guidelines for antimicrobial stewardship in emergency departments (endorsed by European association of hospital pharmacists)

SCOPE

This European Society of Clinical Microbiology and Infectious Diseases guideline provides evidence-based recommendations to support a selection of appropriate antibiotic use practices for patients seen in the emergency department (ED) and guidance for their implementation. The topics addressed in this guideline are (a) Do biomarkers or rapid pathogen tests improve antibiotic prescribing and/or clinical outcomes? (b) Does taking blood cultures in common infectious syndromes improve antibiotic prescribing and/or clinical outcomes? (c) Does watchful waiting without antibacterial therapy or with delayed antibiotic prescribing reduce antibiotic prescribing without worsening clinical outcomes in patients with specific infectious syndromes? (d) Do structured culture follow-up programs in patients discharged from the ED with cultures pending improve antibiotic prescribing?

METHODS

An expert panel was convened by European Society of Clinical Microbiology and Infectious Diseases and the guideline chair. The panel selected in consensus the four most relevant antimicrobial stewardship topics according to pre-defined relevance criteria. For each main question for the four topics, a systematic review was performed, including randomized controlled trials and observational studies. Both clinical outcomes and stewardship process outcomes related to antibiotic use were deemed relevant. The literature searches were conducted between May 2021 and March 2022. In April 2022, the panel members were formally asked to suggest additional studies that were not identified in the initial searches. Data were summarized in a meta-analysis if possible or otherwise summarized narratively. The certainty of the evidence was classified according to the Grading of Recommendations Assessment, Development and Evaluation criteria. The guideline panel reviewed the evidence per topic critically appraising the evidence and formulated recommendations through a consensus-based process. The strength of the recommendations was classified as strong or weak. To substantiate the implementation process, implementation trials or observational studies describing facilitators/barriers for implementation were identified from the same searches and were summarized narratively.

RECOMMENDATIONS

The recommendations on the use of biomarkers and rapid pathogen diagnostic tests focus on the initiation of antibiotics in patients admitted through the ED. Their effect on the discontinuation or de-escalation of antibiotics during hospital stay was not reported, neither was their effect on hospital infection prevention and control practices. The recommendations on watchful waiting (i.e. withholding antibiotics with some form of follow-up) focus on specific infectious syndromes for which the primary care literature was also included. The recommendations on blood cultures focus on the indication in three common infectious syndromes in the ED explicitly excluding patients with sepsis or septic shock. Most recommendations are based on very low and low certainty of evidence, leading to weak recommendations or, when no evidence was available, to best practice statements. Implementation of these recommendations needs to be adapted to the specific settings and circumstances of the ED. The scarcity of high-quality studies in the area of antimicrobial stewardship in the ED highlights the need for future research in this field.

Clinical effects of bacteremia in sepsis patients with community-acquired pneumonia

BACKGROUND

Data regarding the clinical effects of bacteremia on severe community-acquired pneumonia (CAP) are limited. Thus, we investigated clinical characteristics and outcomes of severe CAP patients with bacteremia compared with those of subjects without bacteremia. In addition, we evaluated clinical factors associated with bacteremia at the time of sepsis awareness.

METHODS

We enrolled sepsis patients diagnosed with CAP at emergency departments (EDs) from an ongoing nationwide multicenter observational registry, the Korean Sepsis Alliance, between September 2019 and December 2020. For evaluation of clinical factors associated with bacteremia, we divided eligible patients into bacteremia and non-bacteremia groups, and logistic regression analysis was performed using the clinical characteristics at the time of sepsis awareness.

RESULT

During the study period, 1,510 (47.9%) sepsis patients were caused by CAP, and bacteremia was identified in 212 (14.0%) patients. Septic shock occurred more frequently in the bacteremia group than in the non-bacteremia group (27.4% vs. 14.8%; p < 0.001). In multivariable analysis, hematologic malignancies and septic shock were associated with an increased risk of bacteremia. However, chronic lung disease was associated with a decreased risk of bacteremia. Hospital mortality was significantly higher in the bacteremia group than in the non-bacteremia group (27.3% vs. 40.6%, p < 0.001). The most prevalent pathogen in blood culture was Klebsiella pneumoniae followed by Escherichia coli in gram-negative pathogens.

CONCLUSION

The incidence of bacteremia in severe CAP was low at 14.0%, but the occurrence of bacteremia was associated with increased hospital mortality. In severe CAP, hematologic malignancies and septic shock were associated with an increased risk of bacteremia.

Implementation of Prediction Models in the Emergency Department from an Implementation Science Perspective-Determinants, Outcomes, and Real-World Impact: A Scoping Review

STUDY OBJECTIVE

Prediction models offer a promising form of clinical decision support in the complex and fast-paced environment of the emergency department (ED). Despite significant advancements in model development and validation, implementation of such models in routine clinical practice remains elusive. This scoping review aims to survey the current state of prediction model implementation in the ED and to provide insights on contributing factors and outcomes from an implementation science perspective.

METHODS

We searched 4 databases from their inception to May 20, 2022: MEDLINE (through PubMed), Embase, Scopus, and CINAHL. Articles that reported implementation outcomes and/or contextual determinants under the Reach, Effectiveness, Adoption, Implementation Maintenance (RE-AIM)/Practical, Robust, Implementation, and Sustainability Model (PRISM) framework were included. Characteristics of studies, models, and results of the RE-AIM/PRISM domains were summarized narratively.

RESULTS

Thirty-six reports on 31 implementations were included. The most common prediction models implemented were early warning scores. The most common implementation strategies used were training stakeholders, infrastructural changes, and using evaluative or iterative strategies. Only one report examined ED patients' perspectives, whereas the rest were focused on the experience of health care workers or organizational stakeholders. Key determinants of successful implementation include strong stakeholder engagement, codevelopment of workflows and implementation strategies, education, and usability.

CONCLUSION

Examining ED prediction models from an implementation science perspective can provide valuable insights and help guide future implementations.

A Fatal Case of Pseudomonas aeruginosa Community-Acquired Pneumonia in an Immunocompetent Patient: Clinical and Molecular Characterization and Literature Review

Rare cases of Pseudomonas aeruginosa community-acquired pneumonia (PA-CAP) were reported in non-immunocompromised patients. We describe a case of Pseudomonas aeruginosa (PA) necrotizing cavitary CAP with a fatal outcome in a 53-year-old man previously infected with SARS-CoV-2, who was admitted for dyspnea, fever, cough, hemoptysis, acute respiratory failure and a right upper lobe opacification. Six hours after admission, despite effective antibiotic therapy, he experienced multi-organ failure and died. Autopsy confirmed necrotizing pneumonia with alveolar hemorrhage. Blood and bronchoalveolar lavage cultures were positive for PA serotype O:9 belonging to ST1184. The strain shares the same virulence factor profile with reference genome PA01. With the aim to better investigate the clinical and molecular characteristics of PA-CAP, we considered the literature of the last 13 years concerning this topic. The prevalence of hospitalized PA-CAP is about 4% and has a mortality rate of 33-66%. Smoking, alcohol abuse and contaminated fluid exposure were the recognized risk factors; most cases presented the same symptoms described above and needed intensive care. Co-infection of PA-influenza A is described, which is possibly caused by influenza-inducing respiratory epithelial cell dysfunction: the same pathophysiological mechanism could be assumed with SARS-CoV-2 infection. Considering the high rate of fatal outcomes, additional studies are needed to identify sources of infections and new risk factors, along with genetic and immunological features. Current CAP guidelines should be revised in light of these results.

Adherence to use of blood cultures according to current national guidelines and their impact in patients with community acquired pneumonia: A retrospective cohort

BACKGROUND

Community acquired pneumonia (CAP) is the most frequent cause of mortality secondary to infectious etiologies. Recommendations about the use of blood cultures in the diagnosis and treatment of CAP has been a contentious topic of debate and ever-changing recommendations.

METHODS

A cohort study was conducted in a community teaching hospital. All the patients that were admitted with a diagnosis of CAP, between January and December of 2019 were included. Sociodemographic and clinical characteristics were obtained. Blood cultures results were obtained, and it was evaluated if they were done in compliance with current recommendations by the Infectious Disease Society of America (IDSA).

RESULTS

721 patients were included in the study. Median age was 68 years and 50% of the patients were male (n = 293). Patients presented from home (84%) and the most common comorbidities were hypertension and diabetes (68% and 31%). 96 patients had positive blood culture and 34% (n = 247) of all the blood cultures were adequately ordered. 80 patients died or went to hospice and the median length of hospital stay in our cohort was 7 days. The multivariate model showed that mortality was associated with positive blood cultures (OR = 3.1 95%CI 1.63-5.87) and appropriateness of blood cultures (OR = 2.96 95% CI 1.2-5.7).

CONCLUSION

Adequate use of blood cultures in patients with CAP might have some association with the outcomes of this disease. However, a prospective study evaluating the utility of this test following current IDSA recommendations is needed to understand their impact in mortality and morbidity.

The Shapiro-Procalcitonin algorithm (SPA) as a decision tool for blood culture sampling: validation in a prospective cohort study

PURPOSE

Blood cultures (BC) are the gold standard for bacteremia detection despite a relatively low diagnostic yield and high costs. A retrospective study reported high predictive values for BC positivity when combining the clinical Shapiro score with procalcitonin (PCT).

METHODS

Single-center, prospective cohort study between 01/2016 and 02/2017 to validate SPA algorithm, including a modified Shapiro score ≥ 3 points (S) PLUS admission PCT > 0.25 µg/l (P), or presence of overruling safety criteria (A) in patients with systemic inflammatory response syndrome. The diagnostic yield of SPA compared to non-standardized clinical judgment in predicting BC positivity was calculated and results presented as odds ratios (OR) with 95% confidence intervals.

RESULTS

Of 1438 patients with BC sampling, 215 (15%) had positive BC which increased to 31% (173/555) in patients fulfilling SP criteria (OR for BC positivity 9.07 [6.34-12.97]). When adding 194 patients with overruling safety criteria (i.e., SPA), OR increased to 11.12 (6.99-17.69), although BC positivity slightly decreased to 26%. With an area under the receiver operating curve of 0.742, SPA indicated better diagnostic performance than its individual components. Positive BC in 689 patients not fulfilling SPA (sampling according to non-standardized clinical judgment) were rare (3%; OR for BC positivity 0.09 [0.06-0.14]). Eight out of 21 missed pathogens were still identified by sampling the primary infection focus.

CONCLUSIONS

This study validates the high predictive value of SPA for bacteremia, increasing true BC positivity from 15 to 26%. Restricting BC sampling to SPA would have reduced BC sampling by 48%, while still detecting 194/215 organisms (90%), which makes SPA a valuable diagnostic stewardship tool.

The change in age distribution of CAP population in Korea with an estimation of clinical implications of increasing age threshold of current CURB65 and CRB65 scoring system

Background

CURB65 and CRB65 score are simple and popular methods to estimate the mortality in patients with community-acquired pneumonia (CAP). Although there has been a global increase in life expectancy and population ageing, we are still using the same age threshold derived from patients in late 1990s to calculate the scores. We sought to assess the implication of using higher age threshold using Korean population data and a single center hospital records.

Methods

Using Korean National Health Insurance Service-National Sample Cohort (NHIS-NSC), we analyzed annual age distribution of CAP patients in Korea from 2005 to 2013 and report how patients aged >65 years increased over time. We also assessed annual change in test characteristics of various age threshold in Korean CAP population. Using a single center hospital registry of CAP patients (2008–2017), we analyzed test characteristics of CURB65 and CRB65 scores with various age thresholds.

Results

116,481 CAP cases were identified from NHIS-NSC dataset. The proportion of patients aged >65 increased by 1.01% (95% CI, 0.70%-1.33%, P<0.001) every year. In the sample Korean population dataset, age threshold showed its peak AUROC (0.829) at 70. In the hospital dataset, 7,197 cases were included for analysis. The AUROC of both CRB65 and CURB65 was maximized at 71. When CRB71 was applied instead of CRB65 for hospital referral using score <1 to define a low-risk case, the potential hospital referral was significantly decreased (72.9% to 64.6%, P<0.001) without any significant increase in 1-month mortality in the low risk group (0.6% to 0.7%, P = 0.690).

Conclusion

There was a significant age shift in CAP population in Korea. Increasing the current age threshold of CURB65 (or CRB65) could be a viable option to reduce ever-increasing hospital referrals and admissions of CAP patients.