IDSA/ESCMID 2026 Guidelines on Staphylococcus aureus Bacteremia: Risk Stratification, Diagnostic Evaluation, and Management of Adults and Children

Background

Staphylococcus aureus bacteremia (SAB) is a common and complex infection that causes significant morbidity due to its frequent association with deep-seated and metastatic foci of infection. Globally, S. aureus is the leading cause of death from bloodstream infection [1]; all-cause 30-day mortality rates range from 15-30% with higher mortality among patients with methicillin-resistant S. aureus (MRSA) bacteremia [2-5]. The burden of SAB is increasing in some regions [6, 7] and is further compounded by growing patient complexity, including the increasing use of implantable prosthetic devices [8].

The spectrum of disease manifestations in SAB is broad and varies widely in severity, ranging from localized skin and soft tissue infections to disseminated infection with multiple metastatic foci. Patients can present with a myriad of clinical syndromes associated with deep-seated foci of infection, including endocarditis, cardiac device infection, septic thrombophlebitis, osteoarticular infections, pneumonia, and deep tissue abscesses (e.g., epidural, psoas, hepatic, splenic, or renal abscesses).

The current paradigm of defining SAB as “complicated” or “uncomplicated” is limited by inconsistent definitions and oversimplification of a complex and heterogeneous disease that is dynamic with an evolving clinical course. Risk factors for complicated SAB are often regarded as having an established diagnosis of deep-seated or metastatic infection, despite low to moderate predictive value which can lead to misclassification and unnecessary prolonged antibiotic use [9]. On the other hand, metastatic seeding may be occult at initial presentation in up to one third of patients [10, 11], and failure to detect these clinically silent foci can result in erroneous labeling as “uncomplicated” SAB and inadequate therapy [11]. As delayed or inadequate source control is strongly associated with poor outcomes, including persistent bacteremia and mortality [5, 12, 13], investigation for deep-seated and metastatic foci of infection is critical.

An alternative framework is needed to guide the diagnostic evaluation and management of SAB that is individualized according to clinical presentation and risk factors for deep-seated and metastatic foci. Additionally, the diagnostic evaluation and management of SAB should be guided by ongoing reassessment of disease evolution and modified accordingly based on a precise clinical diagnosis.

Scope

The overall scope of the SAB guideline project (including current and future publications) includes (1) a risk stratification-based approach to evaluation of patients with SAB (2) diagnostic evaluation of SAB; and (3) management of SAB including antibiotic selection and duration of therapy. Available evidence for adults and children with SAB was reviewed and consensus statements were developed.

The scope of the current manuscripts include seven consensus statements focused on risk stratification, diagnostic evaluation (e.g., follow-up blood cultures, echocardiography, [18F]FDG-PET/CT), and duration of therapy. Future manuscripts will address the management of MRSA and methicillin-susceptible S. aureus (MSSA) bacteremia.

This guideline project is intended for use by adult and pediatric healthcare professionals including physicians, advanced practice providers, and pharmacists who care for patients with SAB. The target audience includes but is not limited to infectious diseases specialists, clinical microbiologists, hospitalists, emergency care clinicians, intensivists, and health systems research and policymakers.

Methods

This group of clinical questions (1 through 7) from the Infectious Diseases Society of America (IDSA) SAB guideline project was developed as consensus statements rather than using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology. IDSA guideline panels develop consensus statements when clinical questions are not optimally structured in PICO format or when limited direct comparative data are available to inform those questions. For this guideline project, this was the case despite a comprehensive literature search conducted across three databases. Clinically important questions in domains such as risk stratification, follow-up blood cultures, diagnostic evaluation, and treatment duration could not be easily structured in a PICO format, and direct comparative data for populations of interest were limited. The consensus statements were developed considering the balance of benefits and harms, feasibility, and resource use, while also providing practical advice for implementation and identifying key research gaps.

Consensus statements were developed using an iterative, structured process that incorporated input from both topic-specific subgroups and the full multidisciplinary panel. Subgroups drafted preliminary statements based on a comprehensive review of the available literature and expert clinical judgment. Draft statements were then reviewed and discussed during multiple virtual panel meetings and refined through sequential rounds of asynchronous electronic feedback. Disagreements and areas of limited agreement were systematically identified, documented, and addressed through targeted discussion and revision. Statements were modified iteratively until convergence was achieved. Final consensus for each statement was defined a priori as agreement by >75% of panel members.

Clinical questions were initially developed with a focus on adult patients. Panelists with expertise in pediatric infectious diseases evaluated the degree to which posed questions could be applied to children and reviewed the relevant pediatric literature when available. Panel members considered whether there was sufficient evidence to support the application of the same consensus statement to children or whether available evidence supported an alternative consensus statement. Each consensus statement is divided into sections containing guidance for adults and children. 

The four panel co-chairs were selected by the leadership of IDSA and the European Society of Clinical Microbiology and Infectious Diseases (ESCMID). Twenty-three additional panelists comprised the full panel, including nine representatives from IDSA, ten from ESCMID, and one representative each from the Pediatric Infectious Diseases Society (PIDS), the European Society for Paediatric Infectious Diseases (ESPID), the Society for Healthcare Epidemiology of America (SHEA), and the American Society of Health-System Pharmacists (ASHP). The panel included physicians and pharmacists with expertise in adult and pediatric infectious diseases and clinical microbiology. Panelists represented diverse geographic regions and levels of clinical experience. IDSA staff oversaw all methodological, administrative, and logistical aspects of guideline development. The panel reviewed the available literature and contributed professional expertise and clinical judgment throughout the guideline development process.

Framework for Risk Stratification and Diagnostic Evaluation and Management of SAB 

A risk stratification framework (Consensus Statement 1, Figure 1) is suggested for adult patients that offers a more nuanced and adaptive approach than the traditional classification of SAB as “complicated” or “uncomplicated.” Furthermore, it accounts for the heterogeneity of SAB and its evolving clinical course. This framework uses a stepwise approach to initially stratify patients as either at low risk or at increased risk for deep-seated or metastatic foci of infection and relapse. Diagnostic evaluation then leads to a final classification of SAB with or without deep-seated or metastatic foci of infection and ultimately guides treatment decisions. This risk-informed approach emphasizes the importance of appropriate diagnostic evaluation, minimizing the risk of missed occult foci of infection while avoiding unnecessarily prolonged antibiotic exposure in patients without confirmed deep-seated or metastatic foci of infection. The initial evaluation of patients with SAB should include a detailed history of illness and physical exam to assess for risk factors and signs and symptoms of deep-seated or metastatic foci of infection [14], follow-up blood cultures and transthoracic echocardiography (TTE). Prompt removal of central venous catheters is recommended as delayed removal is associated with increased risk of hematogenous complications and relapse [15, 16]. Infectious disease consultation is strongly encouraged to guide diagnostic evaluation and management [17-19].

As detailed in Consensus Statement 1, the panel identified three key risk factors that are consistently associated with an increased risk of deep-seated infection, metastatic foci of infection, or relapse in adults and highlighted several other important factors, while acknowledging that additional risk factors may exist. Patients classified as having low-risk SAB have no risk factors or signs of deep-seated or metastatic foci of infection based on clinical assessment and initial diagnostic evaluation, including follow-up blood cultures (Consensus Statement 2) and transthoracic echocardiography (TTE) (Consensus Statement 3). Patients classified as having increased-risk SAB have at least one risk factor. Importantly, risk exists along a continuum and is dynamic, evolving over the course of a patient's care. For example, a patient initially classified as having low-risk SAB may subsequently be determined to have increased-risk SAB. Thus, ongoing clinical evaluation and serial physical examinations are essential components of risk assessment.

The intensity of the diagnostic evaluation should be guided by risk assessment. While adult patients who are stratified as having low-risk SAB may not require additional evaluation beyond follow-up blood cultures and TTE, patients with increased-risk SAB should have tailored workup directed by patient-specific characteristics, ongoing clinical assessment and repeated exams. Patients with multiple risk factors and persistently positive blood cultures may require more extensive diagnostic evaluation than someone with a single risk factor. A risk-stratified approach to transesophageal echocardiography (TEE) among patients with a negative TTE is provided, taking into consideration the quality and interpretability of TTE, and anticipated impact of TEE findings on management (Consensus Statement 4). Additionally, the guidelines address the potential role of whole-body imaging (e.g. [18F]FDG-PET/CT) in patients with increased risk SAB with an unknown focus after appropriate initial evaluation (Consensus Statement 5). 

Establishing a diagnosis of SAB with or without deep-seated or metastatic foci of infection is a critical step to guide duration of therapy and need for source control interventions. Timely source control is associated with earlier clearance of bacteremia and improved mortality [12] and is an essential component in the management of patients with SAB. Consensus Statement 6 suggests a 14-day treatment duration in patients who are stratified as low-risk SAB and classified as without evidence of deep-seated or metastatic foci of infection. Consensus Statement 7 addresses duration of therapy in patients stratified as increased-risk SAB but classified as without evidence of deep-seated or metastatic foci of infection. In such cases, patients with increased-risk SAB can receive 14 days of therapy if there is resolution of signs and symptoms of infection and tailored diagnostic evaluation and ongoing clinical assessment does not reveal a deep-seated or metastatic focus of infection. The panel outlines several scenarios in which longer treatment durations should be considered, particularly when infection cannot be definitively excluded despite a thorough diagnostic evaluation and concern for deep-seated infection remains high. A table of definitions used throughout these guidelines is included in the end of the manuscript and the Supplementary Material of each consensus statement manuscript.

Figure 1. Framework for Risk Stratification and Diagnostic Evaluation of SAB in Adult Patients

^{Disclaimer: The listed risk factors are based on a review of the literature and expert opinion and do not represent an exhaustive or comprehensive list of all risk factors associated with increased risk SAB.}

This framework outlines the approach to risk stratification, diagnostic evaluation, and classification of adult patients into a final diagnosis of SAB with or without deep-seated or metastatic foci. It uses a stepwise approach to guide appropriate diagnostic evaluation, minimizing the risk of missed occult infectious foci while avoiding unnecessary prolonged antibiotic exposure in patients without confirmed deep-seated or metastatic foci of infection. An initial evaluation is performed in all patients with SAB that enables patients to be stratified into “low-risk” or “increased-risk” SAB. Patients stratified as “increased risk” will undergo tailored diagnostic evaluation based on clinical findings (e.g., symptom/exam-directed imaging) and individual patient characteristics. Due to the dynamic nature of SAB, ongoing clinical assessment is necessary to guide diagnostic evaluation. This approach ultimately supports appropriate classification of patients into a final diagnosis of SAB with or without a deep-seated or metastatic foci of infection enabling treatment decisions to be tailored accordingly. Please refer to Consensus Statements (indicated by flags) for additional detail. 

Footnotes 
Abbreviations: CT: Computed Tomography; CVC: central venous catheter; DVT: deep vein thrombosis; FUBC: follow-up blood cultures; ID: infectious diseases; MRI: magnetic resonance imaging; PET/CT: Positron Emission Tomography/Computed Tomography; SAB: Staphylococcus aureus bacteremia; TEE: transesophageal echocardiography; TTE: transthoracic echocardiography. 
¹Endocarditis increased-risk features for endocarditis: presence of an intracardiac device2, predisposing heart valve conditions,3 positive blood culture obtained ≥48 hours after the first positive blood culture, embolic events, more than one non-contiguous focus of infection, community-onset SAB, injection drug use.
²Intracardiac device: prosthetic heart valve, permanent pacemaker, automatic implantable cardioverter-defibrillator, left ventricular assist device. 
³Predisposing heart valve conditions as defined by 2023 Duke-ISCVID criteria [20].
⁴Endovascular graft: synthetic bypass graft in the vessel wall.
⁵Longer durations of therapy, guided by the likely focus, may be appropriate in select scenarios (e.g., retained intracardiac device, recently placed endovascular graft, DVT at central venous catheter site), particularly in the setting of prolonged bacteremia, or if diagnostic testing is incomplete or indeterminate. In these situations, reassessment of source control should also be considered. 

Consensus Statements and Remarks

Consensus Statement 1

Clinical Question 1

In patients with SAB, which risk factors are associated with deep-seated or metastatic foci of infection (e.g., infective endocarditis, osteomyelitis, deep tissue abscess, septic thrombophlebitis, cardiac device-associated infection, septic arthritis,) or relapse of infection?

Adullt Population

Consensus Statements

• The panel suggests stratification based on risk factors associated with deep-seated or metastatic foci of infection or relapse of infection and ongoing clinical assessment to guide the diagnostic evaluation, and treatment plan (Figure 1) (consensus).
• Because individual risk factors lack sufficient negative predictive value to exclude deep-seated or metastatic foci of infection, the panel suggests a risk stratification approach using:
  • Key risk factors consistently associated with deep-seated or metastatic foci of infection or relapse of infection: (1) community-onset SAB (2) positive blood culture obtained ≥48 hours after the first positive blood culture, and (3) presence of an intracardiac device AND
  • Other important risk factors: predisposing heart valve conditions, injection drug use, endovascular graft, SAB in prior 90 days, signs or symptoms of a deep-seated or metastatic focus of infection, embolic events, more than one non-contiguous focus of infection, and unknown focus (consensus).

Remarks

• Risk stratification promotes appropriate diagnostic evaluation, enabling classification of patients into SAB with and without deep-seated or metastatic foci of infection. This approach guides individualized patient management decisions including source control interventions, antibiotic choice, and duration of therapy. It aims to establish greater precision in diagnosis to avoid both undertreatment and overtreatment.
• The terms “uncomplicated” and “complicated” SAB are subjective, imprecise, and inadequate to guide management. The panel suggests using terms that refer to the risk of a specific adverse outcome, i.e., “low risk” or “increased risk” of deep-seated or metastatic foci of infection or relapse of infection. 
• Validation of the risk stratification framework is needed. 

Pediatric Population

Consensus Statements

• The panel suggests that all children with SAB are evaluated for a deep-seated focus of infection (consensus).
• Data are insufficient to define a subgroup of children with SAB who are at low risk of deep-seated or metastatic foci of infection or relapsed bacteremia (consensus).

Remarks

• There are age-related differences in the epidemiology and pathophysiology of SAB and comorbidities, which make it unclear to what extent outcomes and risk factors identified in studies focusing on adults can be directly applied to pediatric practice.
• Children with SAB usually have a clinically or diagnostically identifiable focus of infection, most commonly a musculoskeletal source in community-onset infections.
• Neonates with SAB are less likely to have a focus of infection while also having a higher rate of endocarditis; such patients should be considered separately from older children. The observed higher risk of endocarditis in neonates/premature infants may be at least partly attributable to other comorbidities and/or the need for invasive procedures.
• In all children with SAB, a symptom- and history-based approach to evaluation for the source of bacteremia is warranted.
• Positive blood cultures obtained ≥48 hours after the first positive blood culture may be associated with the presence of deep-seated or metastatic foci of infection (e.g., osteomyelitis, endocarditis, septic thrombophlebitis). 

Consensus Statement 2

Clinical Question 2

Should follow-up blood cultures (FUBC) be performed until negative in patients with SAB? 

Adult Population

Consensus Statement

• In adult patients with SAB, the panel suggests at least 2 sets of FUBC be obtained at 48 hours after sampling of the first positive blood culture and then repeated as either 1 or 2 sets every 24 to 48 hours until negative to document blood culture clearance (consensus).

Remarks

• The term blood culture refers to a set of two bottles (1 aerobic and 1 anaerobic).
• Positive FUBC at ≥48 hours after the first positive blood culture should trigger further diagnostic evaluation and source control reassessment as outlined for increased-risk SAB in Consensus Statement 1.
• The FUBC strategy should be individualized with consideration of more intensive monitoring (e.g. FUBC every 24 hours, sampling of 2 sets, negative blood cultures on 2 consecutive days to document clearance) in patients with ongoing signs/symptoms of infection, confirmed or suspected deep-seated focus of infection including endocarditis or other endovascular focus (e.g. intracardiac device or endovascular foreign material), or those with positive FUBC at ≥48 hours.
• Blood culture clearance is defined as the point in time when the first negative blood culture is obtained after which no further positive blood cultures for S. aureus is documented.
• The day of blood culture clearance should be used as the start date for calculating treatment duration of the bacteremia. In cases where source control occurs after blood culture clearance, the date of focus removal may be counted as the start date of therapy.

Pediatric Population

Consensus Statement

• In pediatric patients with SAB, the panel suggests FUBC be obtained at 48 hours after sampling of the first positive blood culture and then repeated every 24 to 48 hours until negative to document blood culture clearance (consensus). 

Remarks

• In collecting FUBC, attention should be given to obtaining appropriate volumes of blood and number of blood culture bottles specific to patient age and weight to optimize sensitivity while minimizing harm. In many young children, one appropriately filled blood culture bottle may provide adequate sensitivity.
• The FUBC strategy should be individualized with consideration of more intensive monitoring (e.g. FUBC every 24 hrs, sampling of 2 sets, negative blood cultures on 2 consecutive days to document clearance) in patients with ongoing signs/symptoms of infection, confirmed or suspected deep focus of infection including musculoskeletal infection, endocarditis or other endovascular focus (e.g. patients with congenital heart disease, intracardiac device or endovascular foreign material), or those with positive FUBC at ≥ 48 hours.
• The day of blood culture clearance should be used as the start date for calculating treatment duration of the bacteremia. In cases where source control occurs after blood culture clearance, the date of focus removal may be counted as the start date of therapy.

Consensus Statement 3

Clinical Question 3

Should a transthoracic echocardiogram (TTE) be performed in all patients with SAB? 

Adult Population 

Consensus Statement

• The panel suggests routinely performing TTE in all adults with SAB, since the panel could not identify criteria to clearly define a population at very low risk of infective endocarditis (consensus). 

Remarks

• Although there may exist a group of adult patients with SAB at very low risk of endocarditis for whom TTE may be unnecessary, criteria to define such a population have not been consistently established. As endocarditis is a serious complication among adults with SAB and TTE is non-invasive, minimal risk procedure, decisions to forego TTE in this population should be carefully considered.

Pediatric Population

Consensus Statement

• TTE should be routinely performed in children with SAB who have structural heart disease, prolonged bacteremia, or signs and symptoms suggestive of endocarditis, but may be omitted in the absence of such factors and with low suspicion for endocarditis (consensus).

Remark

• The risk of endocarditis in neonates with SAB may be greater than in older children and requires separate consideration.

Consensus Statement 4

Clinical Question 4

In patients with SAB and a negative TTE, should a transesophageal echocardiogram (TEE) be performed?

Adult Population

Consensus Statements

• The panel suggests performing TEE in adults with SAB who have a negative TTE, even if the TTE is of good quality if any of the following endocarditis increased-risk features are present:
  • Intracardiac device (e.g., prosthetic heart valve, permanent pacemaker, automatic implantable cardioverter-defibrillator, left ventricular assist device)
  • Predisposing heart valve conditions including prior endocarditis
  • Positive follow-up blood cultures≥ 48 hours after the first positive blood culture
  • Embolic events
  • More than one non-contiguous focus of infection (consensus)
• The panel suggests consideration of TEE in adults with SAB with community-onset or injection drug use as an endocarditis increased-risk feature. The decision to perform TEE should be guided by TTE quality and interpretability, presence of other endocarditis increased-risk features, clinical response, and anticipated impact on management (consensus).
• The panel suggests that TEE may be unnecessary in adults with SAB who have a negative good quality TTE and are without any endocarditis increased-risk features as outlined in below Remarks and Consensus Statement 1 (consensus).

Remarks

• Features associated with an increased risk of endocarditis include any of the following (Consensus Statement 1):
  • Intracardiac device (e.g., prosthetic heart valve, permanent pacemaker, automatic implantable cardioverter-defibrillator, left ventricular assist device)
  • Predisposing heart valve conditions, including prior endocarditis
  • Positive blood cultures obtained ≥ 48 hours after the first positive blood culture
  • Embolic events
  • More than one non-contiguous focus of infection
  • Community-onset SAB
  • Injection drug use
• There is variability in the literature regarding which patients can be safely classified as low risk for endocarditis who may not require TEE. Clinical prediction scores may help inform the decision to omit TEE but should not replace clinician judgment. 

Pediatric Population

Consensus Statements

• The panel suggests not performing TEE in most pediatric patients with SAB and good quality TTE images. TEE has limited additional diagnostic utility over TTE for exclusion of endocarditis in most young children (consensus).
• TEE should be considered in pediatric patients when TTE is negative or indeterminate AND there is high clinical suspicion of endocarditis (consensus).

Remarks

• TEE has limited additional diagnostic utility over TTE for exclusion of endocarditis in most young children.
• Decisions regarding the performance of TEE in children must consider risks associated with the procedure and anesthesia, as well as the size and age of the patient and the availability of experienced personnel. Close consultation with pediatric cardiologists is recommended.

Consensus Statement 5

Clinical Question 5

In patients with Staphylococcus aureus bacteremia (SAB) at increased risk for deep-seated or metastatic foci of infection and with an unknown focus after appropriate initial evaluation, should whole-body imaging (e.g., [18F]FDG-PET/CT) be performed? 

Adult Population

Consensus Statement

• In adult patients with SAB at increased risk for deep-seated or metastatic foci of infection and with an unknown focus after appropriate initial evaluation, the panel suggests performing either:
  • Whole-body imaging (WBI) (e.g., [18F]FDG-PET/CT) OR
  • Combinations of imaging modalities (e.g., thoracic/ abdominal CT, duplex venous ultrasound, etc.) that evaluate the most likely sites of infectious foci (consensus) 

Remarks

• This consensus statement assumes initial diagnostic evaluation including follow-up blood cultures, echocardiography, and symptom/exam-directed imaging (e.g., MRI spine in patient with back pain) has been performed based on risk stratification and as clinically indicated. Please refer to the Executive Summary and Consensus Statements 1, 2, 3, and 4 for additional details regarding risk stratification and diagnostic evaluation.
• Key risk factors for deep-seated or metastatic foci of infection include (1) community-onset, (2) positive blood culture obtained ≥48 hours after the index positive blood culture, and (3) intracardiac device. Please refer to Consensus Statement 1 for additional risk factors.
• Existing evidence for whole-body imaging in the diagnostic evaluation of SAB is limited to observational studies of [18F]FDG-PET/CT, which suggest [18F]FDG-PET/CT may enable earlier detection of occult infectious foci and can inform subsequent treatment modifications. Knowledge gaps exist including:
  • Impact of [18F]FDG-PET/CT on outcomes such as mortality and relapse of infection when compared to symptom/exam-directed imaging or multimodal imaging approaches (e.g., combinations of imaging modalities that evaluate the most likely sites of infectious foci)
• Decisions regarding imaging approach should be guided by the patient’s clinical condition and availability of each imaging modality. 

Pediatric Population

Consensus Statement

• In pediatric patients with SAB without a focus after appropriate initial evaluation, whole-body imaging (e.g., [18F]FDG-PET/CT or other modality or combination of modalities) should be considered in carefully selected situations (e.g., ongoing SAB and no identifiable focus despite targeted evaluation) (consensus). 

Remarks

• It is relatively rare for children to have clinically unsuspected foci of infection associated with SAB.
• Decisions about the choice of imaging in infants and children should be made based on patient age, size, comorbidities, current clinical condition, and availability of each imaging modality.
• There is insufficient evidence to recommend whole-body imaging using [18F]FDG-PET/CT over a combination of other imaging modalities that evaluate the most likely sites of infectious foci. Whole-body imaging using [18F]FDG-PET/CT should be considered in select pediatric patients with SAB if other diagnostic evaluation is unrevealing, taking into consideration the availability of resources.  
• Neonates and very young infants in particular have potential for wide dissemination of disease and may require a more cautious approach. Consideration of whole-body imaging may be warranted in neonates with persistent SAB as resources and clinical condition allow.

Consensus Statement 6

Clinical Question 6

Should patients stratified as low-risk SAB and classified as without deep-seated or metastatic foci of infection after diagnostic evaluation receive antibiotic therapy for 14 days, less than 14 days, or more than 14 days?

Adult Population

Consensus Statement

• In adult patients stratified as low-risk SAB and classified as without deep-seated or metastatic foci of infection after diagnostic evaluation, the panel suggests an antibiotic treatment duration of 14 days rather than longer or shorter courses (consensus). 

Remarks

• The criteria for SAB at low risk of deep-seated or metastatic foci of infection or relapse of infection are defined in Consensus Statement 1.
• This consensus statement assumes that follow-up blood cultures are collected at 48 hours of sampling of the first positive blood culture, and that blood culture clearance is documented as outlined in Consensus Statement 2.
• The day of blood culture clearance should be used as the start date for calculating treatment duration of the bacteremia. In cases where source control occurs after blood culture clearance, the date of focus removal may be counted as the start date of therapy. 

Pediatric Population

Consensus Statements

• Data are insufficient to define a population of pediatric patients with SAB who have a low risk of deep-seated or metastatic foci of infection or relapse of infection (consensus).
• In otherwise healthy pediatric patients with SAB and no evidence of deep-seated or metastatic foci of infection after appropriate evaluation, the panel suggests an antibiotic duration of 14 days (consensus).

Remarks

• This consensus statement assumes that follow-up blood cultures are collected at 48 hours of sampling of the first positive blood culture, and that blood culture clearance is documented as outlined in Consensus Statement 2.  
• The day of blood culture clearance should be used as the start date for calculating treatment duration of the bacteremia. In cases where source control occurs after blood culture clearance, the date of focus removal may be counted as the start date of therapy.

Consensus Statement 7

Clinical Question 7

Should patients stratified as increased-risk SAB but classified as without deep-seated or metastatic foci of infection after diagnostic evaluation receive antibiotic treatment of 14 days or longer?

Adult Population

Consensus Statement

• In adult patients stratified as increased-risk SAB but classified as without deep-seated or metastatic foci of infection after diagnostic evaluation, the panel suggests antibiotic treatment for 14 days (consensus). 

Remarks

• The criteria for stratification as increased-risk of deep-seated or metastatic foci of infection or relapse of infection are defined in Consensus Statement 1.  
• Positive blood cultures obtained ≥ 48 hours after the first positive blood culture is the most robust predictor of adverse outcomes, suggests lack of source control and should prompt additional diagnostic evaluation for deep-seated or metastatic foci of infection.
• Given this, >14 days of antibiotic therapy should be considered in select patients with prolonged bacteremia especially if the diagnostic evaluation is incomplete or of limited quality.
• The day of blood culture clearance should be used as the start date for calculating treatment duration of the bacteremia. In cases where source control occurs after blood culture clearance, the date of focus removal may be counted as the start date of therapy.

Pediatric Population

Consensus Statement

• In pediatric patients with SAB without deep-seated or metastatic foci of infection after diagnostic evaluation, the panel suggests antibiotic treatment for 14 days (consensus).

Remarks

• There are no established criteria to identify children with increased-risk SAB. Important considerations for risk stratification of children and neonates are noted in Consensus Statement 1.
• Studies informing the optimal duration of therapy in children with SAB are lacking.
• In children with SAB who are at risk for endovascular infection (e.g., congenital heart disease, thrombi, or positive blood cultures obtained ≥ 48 hours after the first positive blood culture) but with a negative diagnostic evaluation, longer than 14 days of therapy may need to be considered, especially if the diagnostic evaluation is incomplete or of limited quality.
• The day of blood culture clearance should be used as the start date for calculating treatment duration of the bacteremia. In cases where source control occurs after blood culture clearance, the date of focus removal may be counted as the start date of therapy.

Table of Definitions

Table 1: Table of Definitions*

^{*This table is intended to promote a shared vocabulary to guide use of consistent terminology for clinical care and future research.} 

References and Notes

References

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20. Fowler, V.G., et al., The 2023 Duke-International Society for Cardiovascular Infectious Diseases Criteria for Infective Endocarditis: Updating the Modified Duke Criteria. Clin Infect Dis, 2023. 77(4): p. 518-526.

Acknowledgments

The panel would like to acknowledge Elena Guadagno, medical librarian, for her contributions to the development and execution of the question-specific literature searches. The panel also thanks Loretta Dzanya and Senam Attipoe for their project coordination and administrative support. The panel further acknowledges the following organizations and selected reviewers for providing constructive feedback on the draft manuscript: the Pediatric Infectious Diseases Society (PIDS), the Society for Healthcare Epidemiology of America (SHEA), the Society of Infectious Diseases Pharmacists (SIDP), the American Society of Health-System Pharmacists (ASHP), the European Society of Clinical Microbiology and Infectious Diseases (ESCMID), Stan Deresinski, Robert Krause, Andre Kalil, and Justin Searns. The panel also acknowledges the contributions of the Standards and Practice Guidelines Subcommittee.

For this first group of the seven guideline questions, Catherine Liu (panel chair at IDSA), Henry F. Chambers (co-chair at IDSA), François Vandenesch (co-chair at ESCMID), and Winfried V. Kern (co-chair at ESCMID) oversaw and guided the whole process of consensus statement development. Achim J. Kaasch, Luke Strnad, Marisa Holubar, Bo Shopsin, and Francois Vandenesch served in the subgroup for the adult sections for questions 1, 2, 6 and 7. Catherine Liu, Vincent Le Moing, Alex Soriano, Vance G. Fowler, and Loren G. Miller served in the subgroup for the adult sections for questions 3, 4, and 5. Aubrey Cunnington and J. Chase McNeil served as clinical leads for the pediatrics section for all questions. Lara A. Kahale, the current IDSA methodologist, contributed to project management, screening, data interpretation, guiding the panel through the drafting of the consensus statement, and drafting the manuscript and supplementary files. The remaining panelists contributed to the interpretation of data, drafting, revision, and final approval of each consensus statement and manuscript. The entire panel was involved in the development of clinical questions, discussions of the literature, drafting of recommendations or consensus statements, and editing of the manuscripts.

Disclaimer

It is important to recognize that guidelines cannot always account for individual variation among patients. They are assessments of current scientific and clinical information provided as an educational service; are not continually updated and may not reflect the most recent evidence (new evidence may emerge between the time information is drafted and when it is published or read); should not be considered inclusive of all proper methods of care, or as a statement of the standard of care; do not mandate any course of medical care; and are not intended to supplant clinician judgment with respect to particular patients or situations. Whether to follow guidelines and to what extent is voluntary, with the ultimate determination regarding their application to be made by the clinician in the light of each patient’s individual circumstances. While the Infectious Diseases Society of America (IDSA) makes every effort to present accurate, complete, and reliable information, these guidelines are presented “as is” without any warranty, either express or implied. IDSA (and its officers, directors, members, employees, and agents) assume no responsibility for any loss, damage, or claim with respect to any liabilities, including direct, special, indirect, or consequential damages, incurred in connection with these guidelines or reliance on the information presented. The guidelines represent the proprietary and copyrighted property of IDSA. All rights reserved. No part of these guidelines may be reproduced, distributed, or transmitted in any form or by any means, including photocopying, recording, or other electronic or mechanical methods, without the prior written permission of IDSA. Permission is granted to physicians and health care providers solely to copy and use the guidelines in their professional practices and clinical decision making. No license or permission is granted to any person or entity, and prior written authorization by IDSA is required to sell, distribute, or modify the guidelines, or to make derivative works of or incorporate the guidelines into any product, including, but not limited to, clinical decision support software or any other software product. Except for the permission granted above, any person or entity desiring to use the guidelines in any way must contact IDSA for approval in accordance with the terms and conditions of third-party use, in particular any use of the guidelines in any software product. 

Conflicts of Disclosure

Possible conflicts of interest. Evaluation of relationships as potential conflicts of interest is determined by a review process. The assessment of disclosed relationships for possible COIs is based on the relative weight of the financial relationship (i.e., monetary amount) and the relevance of the relationship (i.e., the degree to which an association might reasonably be interpreted by an independent observer as related to the topic or recommendation of consideration). 

The following panelists have reported relationships unrelated to the topic of SAB with indicated companies: C.A.A. serves as a writer for UptoDate; serves as Editor in Chief, AAC for American Society for Microbiology. T.B. received honoraria from Gilead Sciences; serves as a research consultant for MSD and Pfizer; receives an honorarium from GSK; receives research funding from Simonsen Foundation. H.B. serves as an editor for Sanford Guide; serves as Editor, ID Clinics of North America for Elsevier; receives research funding from NIH’s ARLG. A.C. served as the Chair of Committee for Scientific Affairs and Awards for the European Society for Pediatric Infectious Disease; receives research funding from NIHR; receives funding from the European Commission. V.F. serves as a research consultant for GSK and Akagera. A.J.K. received research funding from Staatskanzlei Land Sachsen-Anhalt for Evaluation of Pandemic Response; receives research funding from BMBF – Federal Ministry of Education and Research for the Network of University Medicine and from Ministerium für Wissenschaft, Energie und Klimaschutz Sachsen-Anhalt. W.V.K. receives research funding from Baden-Württemberg Federal State Ministry of Science and Art. V.LM. received sponsorship from Advanz; served as a scientific advisor for Advanz Pharma. C.L. receives research funding from SNIPR Biome. M.L. receives research funding from NIHR. E.L.C. participated with the Promotional (non-CME) Speakers Bureau for Glaxosmithkline and for Viiv Healthcare. J.C.M. received research funding from Nabriva Therapeutics; receives research funding from Merck; receives royalties from UpToDate. L.M. receives research funding from Paratek. M.P. receives research funding from Rambam Health Care Campus, and from ERANET JPIAMR (EU). K.J.P. served as a PPGA member of SHEA; receives research funding from NIH. S.R. received research funding from Federal Ministry of Education and Research; receives honoraria for lectures from Akademie für Infektionsmedizin, Med Update GmbH, streamedup! GmbH, Forum für medizinische Fortbildung, Meet The Experts Academy, Deutscher Apotheker-Verlag, Deutsches Beratungszentrum für Hygiene, bioMériux, GSK, and Falk Foundation; receives research funding from German Research Foundation and European Union (Horizon); is an elected member of Steering Committee for The German Society for Infectious Diseases (DGI). M.R. received research funding from Medpace/Armata Pharmaceuticals; serves as a research and marketing consultant for Teleflex; receives research funding from Magnolia. M.C. served as a research consultant for Seikagaku Corporation, for Hall, Booth, Smith, P.C., for Meitheal Pharmaceuticals, Inc., and for Lykos Therapeutics; serves as a research consultant for iFAST, for ARK, and for Third Pole Therapeutics; receives lecture honoraria from various universities; serves as chair of advisory board for DoseMe; receives funding from NIH/FDA.; serves on the Board of Directors with the American College of Clinical Pharmacy. 

The following panelists have reported relationships related to the topic of SAB with indicated companies: H.C.’s spouse has stocks in Merck; serves as a research advisor for Merck’s DSMB. V.F. serves as a research advisor for Basilea and Debiopharm; serves as a research consultant for AstraZeneca and Armata; receives a grant to Duke/DCRI from Basilea, from EDE, from AstraZeneca; and receives research funding from NIH. E.L.C. participated with the Promotional (non-CME) Speakers Bureau for Angelini. L.M. receives research funding from Armata; received research funding from ContraFect, and from GSK. M.P. serves as a guideline methodologist for ESCMID. S.R. receives honoraria from Pfizer. M.R. serves as a member of the scientific advisory board for Citius Pharmaceuticals. A.S. serves on the Promotional (non-CME) Speakers Bureau for Pfizer. L.S. received research study funding from NID/NIAID/DMID. S.T. serves on a research advisory board for AstraZeneca; receives research funding from NHMRC and NIH. F.V. serves as co-funder and medical director of Weezion; receives funding from the French National Research Agency. All other authors reported no disclosures. 

Additional information. The rationale for each recommendation or consensus statement is detailed in each individual manuscript. More detailed information is available in each manuscript’s Supplementary material.

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Update History

As of July X, 2026, IDSA has published part 1 of a new guideline addressing the management of Staphylococcus aureus bacteremia (SAB) in adults and children, including both methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-susceptible Staphylococcus aureus (MSSA) infections.