In this systematic review, we estimated the total number of episodes of bloodstream infection (BSI) and deaths from BSI per year in North America and Europe, using data from population-based settings. Then, we estimated the number of episodes and deaths from nosocomial BSI from population-based studies and nosocomial infection surveillance systems. We estimated 575 000-677 000 episodes of BSI per year in North America (536 000-628 000 in the USA and 40 000-49 000 in Canada) and 79 000-94 000 deaths (72 000-85 000 in the USA and 7000-9000 in Canada), using estimates from three population-based studies. We estimated over 1 200 000 episodes of BSI and 157 000 deaths per year in Europe, using estimates from one population-based study in each of the following countries: Denmark (9100 episodes and 1900 deaths), Finland (8700 episodes and 1100 deaths) and England (96 000 episodes and 12 000-19 000 deaths). There were substantial differences in estimates of nosocomial BSI between population-based and nosocomial infection surveillance data. BSI has a major impact on the morbidity and mortality of the general population, as it ranks among the top seven causes of death in all included countries in North America and Europe. However, it is difficult to obtain precise estimates of nosocomial BSI, owing to the limited number of studies. This review highlights the need for a greater focus on BSI research in order to reduce the overall burden of disease by improving the outcome of patients with BSI. It also emphasizes the role of infection control and prevention methods in reducing the burden of nosocomial BSI.

Intra-abdominal infections (IAI) are an important cause of morbidity and are frequently associated with poor prognosis, particularly in high-risk patients. The cornerstones in the management of complicated IAIs are timely effective source control with appropriate antimicrobial therapy. Empiric antimicrobial therapy is important in the management of intra-abdominal infections and must be broad enough to cover all likely organisms because inappropriate initial antimicrobial therapy is associated with poor patient outcomes and the development of bacterial resistance. The overuse of antimicrobials is widely accepted as a major driver of some emerging infections (such as C. difficile), the selection of resistant pathogens in individual patients, and for the continued development of antimicrobial resistance globally. The growing emergence of multi-drug resistant organisms and the limited development of new agents available to counteract them have caused an impending crisis with alarming implications, especially with regards to Gram-negative bacteria. An international task force from 79 different countries has joined this project by sharing a document on the rational use of antimicrobials for patients with IAIs. The project has been termed AGORA (Antimicrobials: A Global Alliance for Optimizing their Rational Use in Intra-Abdominal Infections). The authors hope that AGORA, involving many of the world's leading experts, can actively raise awareness in health workers and can improve prescribing behavior in treating IAIs.

The bloodstream infection mortality risk score (BSIMRS) predicts the outcome of patients with Gram-negative bloodstream infections (BSI) with high discrimination. This retrospective cohort study examined the impact of inappropriate antimicrobial therapy on mortality in adult patients with Gram-negative BSI admitted to Palmetto Health Hospitals in Columbia, SC, USA, from 1 January 2011 to 31 December 2012 after stratification by predicted prognosis at initial presentation using BSIMRS. A multivariate Cox regression model was used to identify independent risk factors for 28-day mortality overall and within each predefined BSIMRS category (<5, 5 to 9, and ≥10). Relative risk reduction (RRR), absolute risk reduction (ARR), and number needed to treat (NNT) were calculated from a predictive logistic regression model of mortality. Overall, 390 unique patients with first episodes of Gram-negative BSI were identified. The median age was 66 years, and 229 (59%) were women. There was significant association between inappropriate antimicrobial therapy and mortality in patients with BSIMRS of 5 to 9 (adjusted hazard ratio [aHR], 3.55; 95% confidence intervals [CI], 1.22 to 8.31; P = 0.02) and BSIMRS of ≥10 (aHR, 4.99; 95% CI, 1.09 to 22.87; P = 0.04) but not in those with BSIMRS of <5 (aHR, 3.34; 95% CI, 0.17 to 22.77; P = 0.34). RRR, ARR, and NNT were 0.25, 0.02, and 63 for BSIMRS of <5; 0.56, 0.32, and 3 for BSIMRS of 5 to 9; and 0.39, 0.39, and 3 for BSIMRS of ≥10, respectively. There is a significant benefit from appropriate antimicrobial therapy in patients with Gram-negative BSI with guarded (BSIMRS of 5 to 9) and poor (BSIMRS of ≥10) predicted prognosis. Survival difference remains unclear among those with good predicted prognosis (BSIMRS of <5) at initial presentation.

OBJECTIVE: To develop a risk score to predict probability of bloodstream infections (BSIs) due to extended-spectrum β-lactamase–producingEnterobacteriaceae(ESBLE).DESIGN: Retrospective case-control study.SETTING: Two large community hospitals.PATIENTS: Hospitalized adults withEnterobacteriaceaeBSI between January 1, 2010, and June 30, 2015.METHODS: Multivariate logistic regression was used to identify independent risk factors for ESBLE BSI. Point allocation in extended-spectrum β-lactamase prediction score (ESBL-PS) was based on regression coefficients.RESULTS: Among 910 patients withEnterobacteriaceaeBSI, 42 (4.6%) had ESBLE bloodstream isolates. Most ESBLE BSIs were community onset (33 of 42; 79%), and 25 (60%) were due toEscherichia coli. Independent risk factors for ESBLE BSI and point allocation in ESBL-PS included outpatient procedures within 1 month (adjusted odds ratio [aOR], 8.7; 95% confidence interval [CI], 3.1–22.9; 1 point), prior infections or colonization with ESBLE within 12 months (aOR, 26.8; 95% CI, 7.0–108.2; 4 points), and number of prior courses of β-lactams and/or fluoroquinolones used within 3 months of BSI: 1 course (aOR, 6.3; 95% CI, 2.7–14.7; 1 point), ≥2 courses (aOR, 22.0; 95% CI, 8.6–57.1; 3 points). The area under the receiver operating characteristic curve for the ESBL-PS model was 0.86. Patients with ESBL-PSs of 0, 1, 3, and 4 had estimated probabilities of ESBLE BSI of 0.7%, 5%, 24%, and 44%, respectively. Using ESBL-PS ≥3 to indicate high risk provided a negative predictive value of 97%.CONCLUSIONS: ESBL-PS estimated patient-specific risk of ESBLE BSI with high discrimination. Incorporation of ESBL-PS with acute severity of illness may improve adequacy of empirical antimicrobial therapy and reduce carbapenem utilization.Infect Control Hosp Epidemiol2017;38:266–272

Antimicrobial Stewardship Programs (ASPs) have been promoted to optimize antimicrobial usage and patient outcomes, and to reduce the emergence of antimicrobial-resistant organisms. However, the best strategies for an ASP are not definitively established and are likely to vary based on local culture, policy, and routine clinical practice, and probably limited resources in middle-income countries. The aim of this study is to evaluate structures and resources of antimicrobial stewardship teams (ASTs) in surgical departments from different regions of the world. A cross-sectional web-based survey was conducted in 2016 on 173 physicians who participated in the AGORA (Antimicrobials: A Global Alliance for Optimizing their Rational Use in Intra-Abdominal Infections) project and on 658 international experts in the fields of ASPs, infection control, and infections in surgery. The response rate was 19.4%. One hundred fifty-six (98.7%) participants stated their hospital had a multidisciplinary AST. The median number of physicians working inside the team was five [interquartile range 4–6]. An infectious disease specialist, a microbiologist and an infection control specialist were, respectively, present in 80.1, 76.3, and 67.9% of the ASTs. A surgeon was a component in 59.0% of cases and was significantly more likely to be present in university hospitals (89.5%, p < 0.05) compared to community teaching (83.3%) and community hospitals (66.7%). Protocols for pre-operative prophylaxis and for antimicrobial treatment of surgical infections were respectively implemented in 96.2 and 82.3% of the hospitals. The majority of the surgical departments implemented both persuasive and restrictive interventions (72.8%). The most common types of interventions in surgical departments were dissemination of educational materials (62.5%), expert approval (61.0%), audit and feedback (55.1%), educational outreach (53.7%), and compulsory order forms (51.5%). The survey showed a heterogeneous organization of ASPs worldwide, demonstrating the necessity of a multidisciplinary and collaborative approach in the battle against antimicrobial resistance in surgical infections, and the importance of educational efforts towards this goal.