Prospective audit of bacteraemia management in a university hospital ICU using a general strategy of short-course monotherapy

Antibiotic Therapy Strategies for Treating Gram-Negative Severe Infections in the Critically Ill: A Narrative Review

INTRODUCTION

Not enough data exist to inform the optimal duration and type of antimicrobial therapy against GN infections in critically ill patients.

METHODS

Narrative review based on a literature search through PubMed and Cochrane using the following keywords: "multi-drug resistant (MDR)", "extensively drug resistant (XDR)", "pan-drug-resistant (PDR)", "difficult-to-treat (DTR) Gram-negative infection," "antibiotic duration therapy", "antibiotic combination therapy" "antibiotic monotherapy" "Gram-negative bacteremia", "Gram-negative pneumonia", and "Gram-negative intra-abdominal infection".

RESULTS

Current literature data suggest adopting longer (≥10-14 days) courses of synergistic combination therapy due to the high global prevalence of ESBL-producing (45-50%), MDR (35%), XDR (15-20%), PDR (5.9-6.2%), and carbapenemases (CP)/metallo-β-lactamases (MBL)-producing (12.5-20%) Gram-negative (GN) microorganisms (i.e., Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumanii). On the other hand, shorter courses (≤5-7 days) of monotherapy should be limited to treating infections caused by GN with higher (≥3 antibiotic classes) antibiotic susceptibility. A general approach should be based on (i) third or further generation cephalosporins ± quinolones/aminoglycosides in the case of MDR-GN; (ii) carbapenems ± fosfomycin/aminoglycosides for extended-spectrum β-lactamases (ESBLs); and (iii) the association of old drugs with new expanded-spectrum β-lactamase inhibitors for XDR, PDR, and CP microorganisms. Therapeutic drug monitoring (TDM) in combination with minimum inhibitory concentration (MIC), bactericidal vs. bacteriostatic antibiotics, and the presence of resistance risk predictors (linked to patient, antibiotic, and microorganism) should represent variables affecting the antimicrobial strategies for treating GN infections.

CONCLUSIONS

Despite the strategies of therapy described in the results, clinicians must remember that all treatment decisions are dynamic, requiring frequent reassessments depending on both the clinical and microbiological responses of the patient.

Short course antibiotic treatment of Gram-negative bacteraemia (GNB5): a study protocol for a randomised controlled trial

INTRODUCTION

Prolonged use of antibiotics is closely related to antibiotic-associated infections, antimicrobial resistance and adverse drug events. The optimal duration of antibiotic treatment for Gram-negative bacteremia (GNB) with a urinary tract source of infection is poorly defined.

METHODS AND ANALYSIS

Investigator-initiated multicentre, non-blinded, non-inferiority randomised controlled trial with two parallel treatment arms. One arm will receive shortened antibiotic treatment of 5 days and the other arm will receive antibiotic treatment of 7 days or longer. Randomisation will occur in equal proportion (1:1) no later than day 5 of effective antibiotic treatment as determined by antibiogram. Immunosuppressed patients and those with GNB due to non-fermenting bacilli (Acinetobacter spp, Pseudomonas spp), Brucella spp, Fusobacterium spp or polymicrobial growth are ineligible.The primary endpoint is 90-day survival without clinical or microbiological failure to treatment. Secondary endpoints include all-cause mortality, total duration of antibiotic treatment, hospital readmission and Clostridioides difficile infection. Interim safety analysis will be performed after the recruitment of every 100 patients. Given an event rate of 12%, a non-inferiority margin of 10%, and 90% power, the required sample size to determine non-inferiority is 380 patients. Analyses will be performed on both intention-to-treat and per-protocol populations.

ETHICS AND DISSEMINATION

The study is approved by the Danish Regional Committee on Health Research (H-19085920) and the Danish Medicines Agency (2019-003282-17). The results of the main trial and each of the secondary endpoints will be submitted for publication in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

ClinicalTrials.Gov:NCT04291768.

Assessment of a rapid diagnostic test to exclude bacteraemia and effect on clinical decision-making for antimicrobial therapy

Unnecessary antimicrobial treatment promotes the emergence of resistance. Early confirmation that a blood culture is negative could shorten antibiotic courses. The Cognitor Minus test, performed on blood culture samples after 12 hours incubation has a negative predictive value (NPV) of 99.5%. The aim of this study was to determine if earlier confirmation of negative blood culture result would shorten antibiotic treatment. Paired blood cultures were taken in the Critical Care Unit at a teaching hospital. The Cognitor Minus test was performed on one set >12 hours incubation but results kept blind. Clinicians were asked after 24 and 48 hours whether a result excluding bacteraemia or fungaemia would affect decisions to continue or stop antimicrobial treatment. Over 6 months, 125 patients were enrolled. The median time from start of incubation to Cognitor Minus test was 27.1 hours. When compared to 5 day blood culture results from both the control and test samples, Cognitor Minus gave NPVs of 99% and 100% respectively. Test results would have reduced antibiotic treatment in 14% (17/119) of patients at 24 and 48 hours (24% at either time) compared with routine blood culture. The availability of rapid tests to exclude bacteraemia may be of benefit in antimicrobial stewardship.

Short versus long duration antimicrobial treatment for community-onset bacteraemia: A propensity score matching study

The efficacy and safety of short-course intravenous (i.v.) antimicrobial therapy for bloodstream infections is unknown. Therefore, a retrospective 8-year cohort study including 1431 hospitalised adults was conducted to compare the outcomes of patients receiving short-course (5-10 days) and long-course (11-16 days) i.v. antibiotic therapy for community-onset bacteraemia. Of 1010 patients who received short-course therapy, 726 were matched with 363 patients in the long-course group through propensity score matching at a ratio of 1:2 based on independent predictors of 30-day mortality identified in the multivariate regression model. Following appropriate matching, similarities between the two groups in the proportion of baseline characteristics (age, sex, major co-morbidities, co-morbidity severity, bacteraemia severity at onset and major bacteraemia sources) and 30-day crude mortality rate after bacteraemia onset were observed. Notably, clinical outcomes within 30 days after the end of i.v. therapy, in terms of proportions of post-treatment overall infections (2.2% vs. 6.1%; P = 0.001), infections caused by antimicrobial-resistant pathogens (ARPs) (1.7% vs. 4.4%; P = 0.007), and thereby post-treatment crude mortality (1.4% vs. 3.6%; P = 0.009), were lower in the short-course group. In conclusion, for adults with community-onset uncomplicated bacteraemia, short-course (5-10 days) i.v. antibiotic treatment did not result in an increased risk of mortality but instead decreased the odds of overall and ARP infections after the treatment course.

Significant Publications on Infectious Diseases Pharmacotherapy in 2017

PURPOSE

The most significant peer-reviewed articles pertaining to infectious diseases (ID) pharmacotherapy, as selected by panels of ID pharmacists, are summarized.

SUMMARY

Members of the Houston Infectious Diseases Network (HIDN) were asked to nominate peer-reviewed articles that they believed most contributed to the practice of ID pharmacotherapy in 2017, including the areas of human immunodeficiency virus (HIV) and acquired immunodeficiency syndrome (AIDS). A list of 33 articles related to general ID pharmacotherapy and 4 articles related to HIV/AIDS was compiled. A survey was distributed to members of the Society of Infectious Diseases Pharmacists (SIDP) for the purpose of selecting 10 articles believed to have made the most significant impact on general ID pharmacotherapy and the single significant publication related to HIV/AIDS. Of 524 SIDP members who responded, 221 (42%) and 95 (18%) members voted for general pharmacotherapy- and HIV/AIDS-related articles, respectively. The highest ranked articles are summarized below.

CONCLUSION

Remaining informed on the most significant ID-related publications is a challenge when considering the large number of ID-related articles published annually. This review of significant publications in 2017 may aid in that effort.

Top Questions in Uncomplicated, Non-Staphylococcus aureus Bacteremia

The Infectious Diseases Society of America infection-specific guidelines provide limited guidance on the management of focal infections complicated by secondary bacteremias. We address the following 3 commonly encountered questions and management considerations regarding uncomplicated bacteremia not due to Staphylococcus aureus: the role and choice of oral antibiotics focusing on oral beta-lactams, the shortest effective duration of therapy, and the role of repeat blood cultures.

Comparing the Outcomes of Adults With Enterobacteriaceae Bacteremia Receiving Short-Course Versus Prolonged-Course Antibiotic Therapy in a Multicenter, Propensity Score-Matched Cohort

Background

The recommended duration of antibiotic treatment for Enterobacteriaceae bloodstream infections is 7-14 days. We compared the outcomes of patients receiving short-course (6-10 days) vs prolonged-course (11-16 days) antibiotic therapy for Enterobacteriaceae bacteremia.

Methods

A retrospective cohort study was conducted at 3 medical centers and included patients with monomicrobial Enterobacteriaceae bacteremia treated with in vitro active therapy in the range of 6-16 days between 2008 and 2014. 1:1 nearest neighbor propensity score matching without replacement was performed prior to regression analysis to estimate the risk of all-cause mortality within 30 days after the end of antibiotic treatment comparing patients in the 2 treatment groups. Secondary outcomes included recurrent bloodstream infections, Clostridium difficile infections (CDI), and the emergence of multidrug-resistant gram-negative (MDRGN) bacteria, all within 30 days after the end of antibiotic therapy.

Results

There were 385 well-balanced matched pairs. The median duration of therapy in the short-course group and prolonged-course group was 8 days (interquartile range [IQR], 7-9 days) and 15 days (IQR, 13-15 days), respectively. No difference in mortality between the treatment groups was observed (adjusted hazard ratio [aHR], 1.00; 95% confidence interval [CI], .62-1.63). The odds of recurrent bloodstream infections and CDI were also similar. There was a trend toward a protective effect of short-course antibiotic therapy on the emergence of MDRGN bacteria (odds ratio, 0.59; 95% CI, .32-1.09; P = .09).

Conclusions

Short courses of antibiotic therapy yield similar clinical outcomes as prolonged courses of antibiotic therapy for Enterobacteriaceae bacteremia, and may protect against subsequent MDRGN bacteria.

PIRATE project: point-of-care, informatics-based randomised controlled trial for decreasing overuse of antibiotic therapy in Gram-negative bacteraemia

INTRODUCTION

Antibiotic overuse drives antibiotic resistance. The optimal duration of antibiotic therapy for Gram-negative bacteraemia (GNB), a common community and hospital-associated infection, remains unknown and unstudied via randomised controlled trials (RCTs).

METHODS AND ANALYSIS

This investigator-initiated, multicentre, non-inferiority, informatics-based point-of-care RCT will randomly assign adult hospitalised patients receiving microbiologically efficacious antibiotic(s) for GNB to (1) 14 days of antibiotic therapy, (2) 7 days of therapy or (3) an individualised duration determined by clinical response and 75% reduction in peak C reactive protein (CRP) values. The randomisation will occur in equal proportions (1:1:1) on day 5 (±1) of efficacious antibiotic therapy as determined by antibiogram; patients, their physicians and study investigators will be blind to treatment duration allocation until the day of antibiotic discontinuation. Immunosuppressed patients and those with GNB due to complicated infections (endocarditis, osteomyelitis, etc) and/or non-fermenting bacilli (Acinetobacter spp, Burkholderia spp, Pseudomonas spp) Brucella spp, Fusobacterium spp or polymicrobial growth with Gram-positive organisms will be ineligible. The primary outcome is incidence of clinical failure at day 30; secondary outcomes include clinical failure, all-cause mortality and incidence of Clostridiumdifficile infection in the 90-day study period. An interim safety analysis will be performed after the first 150 patients have been followed for ≤30 days. Given a chosen margin of 10%, the required sample size to determine non-inferiority is roughly 500 patients. Analyses will be performed on both intention-to-treat and per-protocol populations.

ETHICS AND DISSEMINATION

Ethics approval was obtained from the cantonal ethics committees of all three participating sites. Results of the main trial and each of the secondary endpoints will be submitted for publication in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

This trial is registered at www.clinicaltrials.gov (NCT03101072; pre-results).

Proposal for shorter antibiotic therapies

OBJECTIVES

Reducing antibiotic consumption has now become a major public health priority. Reducing treatment duration is one of the means to achieve this objective. Guidelines on the therapeutic management of the most frequent infections recommend ranges of treatment duration in the ratio of one to two. The Recommendation Group of the French Infectious Diseases Society (SPILF) was asked to collect literature data to then recommend the shortest treatment durations possible for various infections.

METHODS

Analysis of the literature focused on guidelines published in French and English, supported by a systematic search on PubMed. Articles dating from one year before the guidelines publication to August 31, 2015 were searched on the website.

RESULTS

The shortest treatment durations based on the relevant clinical data were suggested for upper and lower respiratory tract infections, central venous catheter-related and uncomplicated primary bacteremia, infective endocarditis, bacterial meningitis, intra-abdominal, urinary tract, upper reproductive tract, bone and joint, skin and soft tissue infections, and febrile neutropenia. Details of analyzed articles were shown in tables.

CONCLUSION

This work stresses the need for new well-conducted studies evaluating treatment durations for some common infections. Following the above-mentioned work focusing on existing literature data, the Recommendation Group of the SPILF suggests specific study proposals.

Pros and cons of using biomarkers versus clinical decisions in start and stop decisions for antibiotics in the critical care setting

INTRODUCTION

Patients in the intensive care unit (ICU) frequently receive prolonged or even unnecessary antibiotic therapy, which selects for antibiotic-resistant bacteria. Over the last decade there has been great interest in biomarkers, particularly procalcitonin, to reduce antibiotic exposure.

METHODS

In this narrative review, we discuss the value of biomarkers and provide additional information beyond clinical evaluation in order to be clinically useful and review the literature on sepsis biomarkers outside the neonatal period. Both benefits and limitations of biomarkers for clinical decision-making are reviewed.

RESULTS

Several randomized controlled trials (RCTs) have shown the safety and efficacy of procalcitonin to discontinue antibiotic therapy in patients with severe sepsis or septic shock. In contrast, there is limited utility of procalcitonin for treatment initiation or withholding therapy initially. In addition, an algorithm using procalcitonin for treatment escalation has been ineffective and is probably associated with poorer outcomes. Little data from interventional studies are available for other biomarkers for antibiotic stewardship, except for C-reactive protein (CRP), which was recently found to be similarly effective and safe as procalcitonin in a randomized controlled trial. We finally briefly discuss biomarker-unrelated approaches to reduce antibiotic duration in the ICU, which have shown that even without biomarker guidance, most patients with sepsis can be treated with relatively short antibiotic courses of approximately 7 days.

CONCLUSIONS

In summary, there is an ongoing unmet need for biomarkers which can reliably and early on identify patients who require antibiotic therapy, distinguish between responders and non-responders and help to optimize antibiotic treatment decisions among critically ill patients. Available evidence needs to be better incorporated in clinical decision-making.

Strategies for appropriate antibiotic use in intensive care unit

The comsumption of antibiotics is high, mainly in intensive care units. Unfortunately, most are inappropriately used leading to increased multi-resistant bacteria. It is well known that initial empirical therapy with broad-spectrum antibiotics reduce mortality rates. However the prolonged and irrational use of antimicrobials may also increase the risk of toxicity, drug interactions and diarrhea due to Clostridium difficile. Some strategies to rational use of antimicrobial agents include avoiding colonization treatment, de-escalation, monitoring serum levels of the agents, appropriate duration of therapy and use of biological markers. This review discusses the effectiveness of these strategies, the importance of microbiology knowledge, considering there are agents resistant to Staphylococcus aureus and Klebsiella pneumoniae, and reducing antibiotic use and bacterial resistance, with no impact on mortality.

Healthcare-associated bloodstream infections in critically ill patients: descriptive cross-sectional database study evaluating concordance with clinical site isolates

Background

Healthcare-associated bloodstream infections are related to both increased antibiotic use and risk of adverse outcomes. An in-depth understanding of their epidemiology is essential to reduce occurrence and to improve outcomes by targeted prevention strategies. The objectives of the study were to determine the epidemiology, source and concordance of healthcare-associated bloodstream infections with clinical site isolates.

Methods

We conducted a descriptive cross-sectional study in critically ill adults admitted to a tertiary semi-closed intensive care unit in England to determine the epidemiology, source and concordance of healthcare-associated bloodstream infections with clinical site isolates. All nosocomial positive blood cultures over a 4-year study period were identified. Pathogens detected and concordances with clinical site are reported as proportions.

Results

Contaminant pathogens accounted for half of the isolates. The most common non-contaminant pathogens cultured were Pseudomonas spp. (8.0%), Enterococcus spp. (7.3%) and Escherichia coli (5.6%). Central venous catheter-linked bloodstream infections represent only 6.0% of the positive blood cultures. Excluding contaminants and central venous line infections, in only 39.5% of the bloodstream infections could a concordant clinical site source be identified, the respiratory and urinary tracts being the most common.

Conclusions

Clinical practice should focus on a) improving blood culture techniques to reduce detection of contaminant pathogens and b) ensuring paired clinical site cultures are performed alongside all blood cultures to better understand the epidemiology and potential implications of primary and secondary discordant health-care associated bloodstream infections.

Long-term adherence to a 5 day antibiotic course guideline for treatment of intensive care unit (ICU)-associated Gram-negative infections

OBJECTIVES

To determine long-term adherence to a 5 day antibiotic course guideline for treating intensive care unit (ICU)-acquired Gram-negative bacteria (GNB) infections.

METHODS

Descriptive analysis of patient-level data on all GNB-active antibiotics prescribed from day 3 and all GNB identified in clinical samples in 5350 patients admitted to a 30 bed general ICU between 2002 and 2009.

RESULTS

Four thousand five hundred and eleven of 5350 (84%) patients were treated with one or more antibiotics active against GNB commenced from day 3. Gentamicin was the most frequently prescribed antibiotic (92.2 days of therapy/1000 patient-days). Only 6% of courses spanned >6 days of therapy and 89% of antibiotic therapy days were with a single antibiotic active against GNB. There was no significant difference between gentamicin and meropenem in the number of first courses in which a resistant GNB was identified in blood cultures [11/1177 (0.9%) versus 5/351 (1.4%); P = 0.43] or respiratory tract specimens [59/951 (6.2%) versus 17/246 (6.9%); P = 0.68] at the time of starting therapy.

CONCLUSIONS

This study demonstrates long-term adherence to a 5 day course antibiotic guideline for treatment of ICU-associated GNB infections. This guideline is a potential antibiotic-sparing alternative to currently recommended dual empirical courses extending to ≥7 days.

Short-course therapy for severe infections

A short course of antimicrobial therapy should be the aim of all treatment unless otherwise indicated. Factors allowing short treatment courses are those that depend on the host, on the infection and on the agents administered. In essence, immunodeficiencies, long-standing infections, abscesses, or infections associated with foreign bodies cannot be treated with short-course therapies. Bactericidal antibiotics are the only agents suitable for short-course therapy. Many severe infections such as primary bacteraemia and bacteraemia complicating pneumonia, acute pyelonephritis and meningitis are amendable to short-course therapy, whilst others are not. The benefits of short-duration therapy are obvious and may contribute to halting resistance, reduced costs and rational patient management.

De-escalation of antimicrobials in the treatment of bacteraemia due to antibiotic-sensitive pathogens in immunocompetent patients

BACKGROUND

The aim of this study was to examine the safety and efficacy of de-escalating antimicrobial therapy in immunocompetent patients presenting with bacteraemia due to antibiotic-sensitive pathogens.

METHODS

We screened 1,350 positive blood cultures identified in a single, 1,065-bed university hospital over 5 years, and retained 310 cases of bacteraemia due to antibiotic-sensitive pathogens, including (1) methicillin-sensitive staphylococci, (2) penicillin-sensitive streptococci, (3) β-lactam-sensitive (a) Escherichia coli, and (b) Klebsiella species. The efficacy of appropriate initial empirical antimicrobial therapy, the performance of de-escalated pathogen-directed therapy, and the safety and efficacy of de-escalated therapy were evaluated.

RESULTS

Among 270 appropriately treated patients, 16 (6%) died, versus 6 (15%) among 40 who were inappropriately treated (p = 0.04). While 201 of 270 patients (74%) who received appropriate initial empirical therapy were candidates for de-escalation, the treatment was de-escalated in only 79 (39%). De-escalation was associated with (1) a trend toward a lower (a) death rate (1 vs. 5%) and (b) treatment failure (4 vs. 10%), and (2) (a) a 4-day longer median duration and (b) a $50 higher median cost of antimicrobial therapy (p < 0.001).

CONCLUSIONS

When the pathogen was sensitive to antimicrobial therapy and the initial empirical treatment was effective, de-escalation of antimicrobial therapy in immunocompetent patients with bacteraemia was safe and associated with acceptable outcomes. The rate of de-escalation of antimicrobial therapy was low.

Infection in the critically ill--questions we should be asking

Best practice in infection control and management in the critically ill continues to generate considerable debate. The wide variation in current practice is witness to this continuing uncertainty. In large part this is due to the lack of a decent evidence base and to an over-reliance on deep-set dogma. Data that go against the grain are often conveniently overlooked and political imperatives frequently supervene. This article highlights some of these discrepancies and argues for a more balanced, scientific approach. In this time of financial restraint, we need to identify true priorities from both health and economic perspectives, and to see what practices can safely and effectively be modified or abandoned.

Effects of pharmaceutical counselling on antimicrobial use in surgical wards: intervention study with historical control group

PURPOSE

The objective of this study was to assess the impact of pharmaceutical consulting on the quality of antimicrobial use in a surgical hospital department in a prospective controlled intervention study.

METHODS

Patients receiving pharmaceutical intervention (intervention group, IG, n = 317) were compared with a historical control group (control group, CG, n = 321). During the control period, antimicrobial use was monitored without intervention. During the subsequent intervention period, a clinical pharmacist reviewed the prescriptions and gave advice on medication.

RESULTS

Intervention reduced the length of antimicrobial courses (IG = 10 days, CG = 11 days, incidence rate ratio for i.v. versus o.p. = 0.88, 95% confidence interval 0.84 to 0.93) and shortened i.v. administration (IG = 8 days, CG = 10 days, hazard rate = 1.76 in favour of switch from i.v. to p.o., 95% confidence interval 1.23 to 2.52). Intervention also helped to avoid useless combination therapy and reduced total costs for antimicrobials.

CONCLUSIONS

A clinical pharmacist who reviews prescriptions can promote an increase in efficiency, for example, by shortening the course of treatment. Counselling by ward-based clinical pharmacists was shown to be effective to streamline antimicrobial therapy in surgical units and to increase drug safety.

Nosocomial bacteremia: impact of empirical antimicrobial treatment on the patients' outcome

OBJECTIVE

To determine the impact on patients' outcome of clinical effectiveness of empirical antimicrobial treatment of nosocomial bacteremia.

SETTING

904-bed hospital, comprising acute care wards, rehabilitation and intermediate care wards and long-term care wards, that provides care primarily for aged (880 beds); design: prospective cohort analysis to access the evidence regarding the effectiveness of empirical antimicrobial treatment in patients with nosocomial bacteremia, when the Gram stain result was communicated to the physician; data collection: data collected concerned patients' characteristics at the early bacteremia, microbiology, antimicrobial treatment and patients' outcome within 30 days; analysis: patients with clinical signs of bacteremia after the Gram stain result were compared with those without symptoms, in univariate analysis.

RESULTS

Significant differences were not found for age, sex, underlying diseases, comorbidities, hospitalization wards, sources of bacteremia, microorganisms or patients' outcome. However, antimicrobial therapies were more often changed in symptomatic patients after the announcement of the Gram stain result (RR = 1.87; [1.03-3.37]; p = 0.04).

CONCLUSION

This study supports the notion that the outcomes for patients are similar whether patients have symptoms or not when the Gram stain result of the first positive blood culture is communicated to the clinician.

Short antibiotic treatment courses or how short is short?

Antibiotic therapy in recent years has become more intense and more frequent. Resistance acquisition by community and hospital strains is however also increasing. One of the methods to halt the increase in resistance may be shorter courses of antibiotics, if their clinical efficacy is not impaired. Shorter courses of antibiotic therapy have been very successful in typhoid fever: 3 days; in meningococcal meningitis: a single dose to 3 days' course; ventilator-associated pneumonia: 8 days; and possibly ICU-associated infections: 3-5 days. On the contrary, IV catheter-associated infections require full treatment courses (14 days). More studies are needed in various infectious entities with various agents to be able to better define the optimal duration of therapy.

[Guidelines for the diagnosis and treatment of patients with bacteriemia. Guidelines of the Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica]

Bacteremia is a complex clinical syndrome in constant transformation that is an important, growing cause of morbidity and mortality. Even though there is a great deal of specific information about bacteremia, few comprehensive reviews integrate this information with a practical AIM. The main objective of these Guidelines, which target hospital physicians, is to improve the clinical care provided to patients with bacteremia by integrating blood culture results with clinical data, and optimizing the use of diagnostic procedures and antimicrobial testing. The document is structured into sections that cover the epidemiology and etiology of bacteremia, stratified according to the various patient populations, and the diagnostic work-up, therapy, and follow-up of patients with bacteremia. Diagnostic and therapeutic decisions are presented as recommendations based on the grade of available scientific evidence.