Antibiotic management of outpatients with endocarditis due to penicillin-susceptible streptococci

Clinical implementation of partial oral treatment in infective endocarditis: the Danish POETry study

BACKGROUND AND AIMS

In the Partial Oral Treatment of Endocarditis (POET) trial, stabilized patients with left-sided infective endocarditis (IE) were randomized to oral step-down antibiotic therapy (PO) or conventional continued intravenous antibiotic treatment (IV), showing non-inferiority after 6 months. In this study, the first guideline-driven clinical implementation of the oral step-down POET regimen was examined.

METHODS

Patients with IE, caused by Staphylococcus aureus, Enterococcus faecalis, Streptococcus spp. or coagulase-negative staphylococci diagnosed between May 2019 and December 2020 were possible candidates for initiation of oral step-down antibiotic therapy, at the discretion of the treating physician. The composite primary outcome in patients finalizing antibiotic treatment consisted of embolic events, unplanned cardiac surgery, relapse of bacteraemia and all-cause mortality within 6 months.

RESULTS

A total of 562 patients [median age 74 years (IQR, interquartile range, 65-80), 70% males] with IE were possible candidates; PO was given to 240 (43%) patients and IV to 322 (57%) patients. More patients in the IV group had IE caused by S. aureus, or had an intra-cardiac abscess, or a pacemaker and more were surgically treated. The primary outcome occurred in 30 (13%) patients in the PO group and in 59 (18%) patients in the IV group (P = .051); in the PO group, 20 (8%) patients died vs. 46 (14%) patients in the IV group (P = .024). PO-treated patients had a shorter median length of stay [PO 24 days (IQR 17-36) vs. IV 43 days (IQR 32-51), P < .001].

CONCLUSIONS

After clinical implementation of the POET regimen almost half of the possible candidates with IE received oral step-down antibiotic therapy. Patients in the IV group had more serious risk factors for negative outcomes. At 6-month follow-up, there was a numerically but not statistically significant difference towards a lower incidence of the primary outcome, a lower incidence of all-cause mortality and a reduced length of stay in the PO group. Due to the observational design of the study, the lower mortality may to some extent reflect selection bias and unmeasured confounding. Clinical implementation of PO regimens seemed feasible and safe.

New Antimicrobials and New Therapy Strategies for Endocarditis: Weapons That Should Be Defended

The overall low-quality evidence concerning the clinical benefits of different antibiotic regimens for the treatment of infective endocarditis (IE), which has made it difficult to strongly support or reject any regimen of antibiotic therapy, has led to a discrepancy between the available guidelines and clinical practice. In this complex scenario, very recently published guidelines have attempted to fill this gap. Indeed, in recent years several antimicrobials have entered the market, including ceftobiprole, ceftaroline, and the long-acting lipoglycopeptides dalbavancin and oritavancin. Despite being approved for different indications, real-world data on their use for the treatment of IE, alone or in combination, has accumulated over time. Furthermore, an old antibiotic, fosfomycin, has gained renewed interest for the treatment of complicated infections such as IE. In this narrative review, we focused on new antimicrobials and therapeutic strategies that we believe may provide important contributions to the advancement of Gram-positive IE treatment, providing a summary of the current in vitro, in vivo, and clinical evidence supporting their use in clinical practice.

Infective Endocarditis in an Intravenous Drug User Leading to Myocardial Rupture and Hemopericardium

Introduction

Infective endocarditis (IE) is an infectious disorder of the innermost lining of the heart that can be fatal if left untreated. Infective endocarditis can spread beyond the endocardium into the myocardium and cause arrhythmias and myocardial wall rupture. Individuals with a history of intravenous drug use are at increased risk of developing IE and are at higher risk of dying, given their limited access to health care and adherence to treatment.

Methods

A medicolegal autopsy was performed on a 30-year-old woman with a history of intravenous drug use and recent assault after a hospital admission during which she did not survive resuscitation.

Results

The cause of death was found to be myocardial rupture in the setting of transmural IE. Postmortem imaging showed hemopericardium which was identified grossly with valvular vegetations in the heart. A ventricular wall defect along with transmural abscess formation was identified. Perimortem toxicology was positive for fentanyl, methamphetamine, and benzoylecgonine, a metabolite of cocaine. Postmortem blood cultures were positive for coagulase-negative Staphylococci, Staphylococcus aureus, Candida tropicalis, and Viridians group Streptococci. Postmortem tissue cultures taken from the heart was positive for Candida glabrata and Streptococcus mitis.

Discussion

The decedent had significant risk factors for IE, such as intravenous drug use and a prior admission to hospital for IE. The organisms identified on culture are in-keeping with the gross findings of IE and the terminal event of myocardial rupture was likely the result of tissue damage resulting from IE.

Real-World Application of Oral Therapy for Infective Endocarditis: A Multicenter, Retrospective, Cohort Study

BACKGROUND

We sought to compare the outcomes of patients treated with intravenous (IV)-only vs oral transitional antimicrobial therapy for infective endocarditis (IE) after implementing a new expected practice within the Los Angeles County Department of Health Services (LAC DHS).

METHODS

We conducted a multicentered, retrospective cohort study of adults with definite or possible IE treated with IV-only vs oral therapy at the 3 acute care public hospitals in the LAC DHS system between December 2018 and June 2022. The primary outcome was clinical success at 90 days, defined as being alive and without recurrence of bacteremia or treatment-emergent infectious complications.

RESULTS

We identified 257 patients with IE treated with IV-only (n = 211) or oral transitional (n = 46) therapy who met study inclusion criteria. Study arms were similar for many demographics; however, the IV cohort was older, had more aortic valve involvement, were hemodialysis patients, and had central venous catheters present. In contrast, the oral cohort had a higher percentage of IE caused by methicillin-resistant Staphylococcus aureus. There was no significant difference between the groups in clinical success at 90 days or last follow-up. There was no difference in recurrence of bacteremia or readmission rates. However, patients treated with oral therapy had significantly fewer adverse events. Multivariable regression adjustments did not find significant associations between any selected variables and clinical success across treatment groups.

CONCLUSIONS

These results demonstrate similar outcomes of real-world use of oral vs IV-only therapy for IE, in accord with prior randomized, controlled trials and meta-analyses.

Choosing patients over placebos: oral transitional therapy vs. IV-only therapy for bacteraemia and infective endocarditis

BACKGROUND

The belief that antibiotics must be administered intravenously (IV) to treat bacteraemia and endocarditis has its origins 70 years ago and has engrained itself in the psyche of the medical community and the public at large. This has led to hesitancy in adopting evidence-based strategies utilizing oral transitional therapy for the treatment of these infections. We aim to reframe the narrative around this debate, focusing on patient safety over vestigial psychology.

OBJECTIVES

This narrative review summarizes the current state of the literature regarding the use of oral transitional therapy for the treatment of bacteraemia and infective endocarditis, focusing on studies comparing it to the traditional, IV-only approach.

SOURCES

Relevant studies and abstracts from PubMed reviewed in April 2023.

CONTENT

Treating bacteraemia with oral transitional therapy has been studied in 9 randomized controlled trials (RCTs), totalling 625 patients, as well as numerous large, retrospective cohorts, including 3 published in the last 5 years alone, totalling 4763 patients. We identified 3 large, retrospective cohort studies; one quasi-experimental, pre-post study, and 3 RCTs of patients with endocarditis, totalling 748 patients in the retrospective cohorts and 815 patients in prospective, controlled studies. In all these studies, no worse outcomes were observed in the oral transitional therapy arm as compared with IV-only therapy. The main difference has consistently been longer durations of inpatient hospitalization and increased risk of catheter-related adverse events like venous thrombosis and line-associated blood stream infections in the IV-only groups.

IMPLICATIONS

There are ample data showing that choosing oral therapy reduces hospital stay and has fewer adverse events for patients than IV-only therapy, all with similar or better outcomes. In selected patients, choosing IV-only therapy may serve more as an anxiolytic "placebo" for the patient and provider rather than a necessity for treating the actual infection.

Guidelines for Diagnosis and Management of Infective Endocarditis in Adults: A WikiGuidelines Group Consensus Statement

Importance

Practice guidelines often provide recommendations in which the strength of the recommendation is dissociated from the quality of the evidence.

Objective

To create a clinical guideline for the diagnosis and management of adult bacterial infective endocarditis (IE) that addresses the gap between the evidence and recommendation strength.

Evidence Review

This consensus statement and systematic review applied an approach previously established by the WikiGuidelines Group to construct collaborative clinical guidelines. In April 2022 a call to new and existing members was released electronically (social media and email) for the next WikiGuidelines topic, and subsequently, topics and questions related to the diagnosis and management of adult bacterial IE were crowdsourced and prioritized by vote. For each topic, PubMed literature searches were conducted including all years and languages. Evidence was reported according to the WikiGuidelines charter: clear recommendations were established only when reproducible, prospective, controlled studies provided hypothesis-confirming evidence. In the absence of such data, clinical reviews were crafted discussing the risks and benefits of different approaches.

Findings

A total of 51 members from 10 countries reviewed 587 articles and submitted information relevant to 4 sections: establishing the diagnosis of IE (9 questions); multidisciplinary IE teams (1 question); prophylaxis (2 questions); and treatment (5 questions). Of 17 unique questions, a clear recommendation could only be provided for 1 question: 3 randomized clinical trials have established that oral transitional therapy is at least as effective as intravenous (IV)-only therapy for the treatment of IE. Clinical reviews were generated for the remaining questions.

Conclusions and Relevance

In this consensus statement that applied the WikiGuideline method for clinical guideline development, oral transitional therapy was at least as effective as IV-only therapy for the treatment of IE. Several randomized clinical trials are underway to inform other areas of practice, and further research is needed.

An Unexpected Outcome of Streptococcus sanguinis Endocarditis Associated With Orthodontic Bracing in a Young Healthy Patient

We present a case of Streptococcus sanguinis endocarditis in a 26-year-old female following orthodontic bracing. The rarity and debilitating consequences of endocarditis caused by Streptococcus sanguinis are elaborated. The patient exhibited severe regurgitation with the eccentric posteriorly directed flow, leading to significant cardiac strain, further accentuated by systolic flow reversal in the right superior pulmonary vein. Surgical intervention, including mitral valve replacement, was crucial in addressing the underlying infection, restoring valve function, and preventing further complications. However, a second mitral valve replacement was performed due to recurrent bioprosthesis endocarditis. This case underscores the unique challenges of Streptococcus sanguinis endocarditis, emphasizing the need for a multidisciplinary approach and individualized decision-making to optimize patient care.

Heartbreaking Decisions: The Dogma and Uncertainties of Antimicrobial Therapy in Infective Endocarditis

Infective endocarditis (IE) is a rare but increasingly prevalent disease with high morbidity and mortality, requiring antimicrobials and at times surgical intervention. Through the decades of healthcare professionals' experience with managing IE, certain dogmas and uncertainties have arisen around its pharmacotherapy. The introduction of new antimicrobials and novel combinations are exciting developments but also further complicate IE treatment choices. In this review, we provide and evaluate the relevant evidence focused around contemporary debates in IE treatment pharmacotherapy, including beta-lactam choice in MSSA IE, combination therapies (aminoglycosides, ceftaroline), the use of oral antimicrobials, the role of rifamycins, and long-acting lipoglycopeptides.

Treatment of Enterococcus faecalis Infective Endocarditis: A Continuing Challenge

Today, Enterococcus faecalis is one of the main causes of infective endocarditis in the world, generally affecting an elderly and fragile population, with a high mortality rate. Enterococci are partially resistant to many commonly used antimicrobial agents such as penicillin and ampicillin, as well as high-level resistance to most cephalosporins and sometimes carbapenems, because of low-affinity penicillin-binding proteins, that lead to an unacceptable number of therapeutic failures with monotherapy. For many years, the synergistic combination of penicillins and aminoglycosides has been the cornerstone of treatment, but the emergence of strains with high resistance to aminoglycosides led to the search for new alternatives, like dual beta-lactam therapy. The development of multi-drug resistant strains of Enterococcus faecium is a matter of considerable concern due to its probable spread to E. faecalis and have necessitated the search of new guidelines with the combination of daptomycin, fosfomycin or tigecycline. Some of them have scarce clinical experience and others are still under investigation and will be analyzed in this review. In addition, the need for prolonged treatment (6–8 weeks) to avoid relapses has forced to the consideration of other viable options as outpatient parenteral strategies, long-acting administrations with the new lipoglycopeptides (dalbavancin or oritavancin), and sequential oral treatments, which will also be discussed.

Outpatient Parenteral Antimicrobial Therapy for Infective Endocarditis-Model of Care

Infective endocarditis (IE) is a serious infectious disease with significant mortality and morbidity placing a burden on healthcare systems. Outpatient antimicrobial therapy in selected patients has been shown to be safe and beneficial to both patients and the healthcare system. In this article, we review the literature on the model of care for outpatient parenteral antimicrobial therapy in infective endocarditis and propose that systems of care be developed based on local resources and all patients admitted with infective endocarditis be screened appropriately for outpatient antimicrobial therapy.

Can the Future of ID Escape the Inertial Dogma of Its Past? The Exemplars of Shorter Is Better and Oral Is the New IV

Like all fields of medicine, Infectious Diseases is rife with dogma that underpins much clinical practice. In this study, we discuss 2 specific examples of historical practice that have been overturned recently by numerous prospective studies: traditional durations of antimicrobial therapy and the necessity of intravenous (IV)-only therapy for specific infectious syndromes. These dogmas are based on uncontrolled case series from >50 years ago, amplified by the opinions of eminent experts. In contrast, more than 120 modern, randomized controlled trials have established that shorter durations of therapy are equally effective for many infections. Furthermore, 21 concordant randomized controlled trials have demonstrated that oral antibiotic therapy is at least as effective as IV-only therapy for osteomyelitis, bacteremia, and endocarditis. Nevertheless, practitioners in many clinical settings remain refractory to adopting these changes. It is time for Infectious Diseases to move beyond its history of eminent opinion-based medicine and truly into the era of evidenced-based medicine.

Oral Is the New IV. Challenging Decades of Blood and Bone Infection Dogma: A Systematic Review

BACKGROUND

We sought to determine if controlled, prospective clinical data validate the long-standing belief that intravenous (IV) antibiotic therapy is required for the full duration of treatment for 3 invasive bacterial infections: osteomyelitis, bacteremia, and infective endocarditis.

METHODS

We performed a systematic review of published, prospective, controlled trials that compared IV-only to oral stepdown regimens in the treatment of these diseases. Using the PubMed database, we identified 7 relevant randomized controlled trials (RCTs) of osteomyelitis, 9 of bacteremia, 1 including both osteomyelitis and bacteremia, and 3 of endocarditis, as well as one quasi-experimental endocarditis study. Study results were synthesized via forest plots and funnel charts (for risk of study bias), using RevMan 5.4.1 and Meta-Essentials freeware, respectively.

RESULTS

The 21 studies demonstrated either no difference in clinical efficacy, or superiority of oral versus IV-only antimicrobial therapy, including for mortality; in no study was IV-only treatment superior in efficacy. The frequency of catheter-related adverse events and duration of inpatient hospitalization were both greater in IV-only groups.

DISCUSSION

Numerous prospective, controlled investigations demonstrate that oral antibiotics are at least as effective, safer, and lead to shorter hospitalizations than IV-only therapy; no contrary data were identified. Treatment guidelines should be modified to indicate that oral therapy is appropriate for reasonably selected patients with osteomyelitis, bacteremia, and endocarditis.

Infective Endocarditis: New Challenges in a Classic Disease

Infective endocarditis is a relatively rare, but deadly infection, with an overall mortality of around 20% in most series. Clinical manifestations have evolved in response to significant epidemiological shifts in industrialized nations, with a move toward a nosocomial or health-care-related pattern, in older patients, with more episodes associated with prostheses and/or intravascular electronic devices and a predominance of staphylococcal and enterococcal etiology.Diagnosis is often challenging and is based on the conjunction of clinical, microbiological, and imaging information, with notable progress in recent years in the accuracy of echocardiographic data, coupled with the recent emergence of other useful imaging techniques such as cardiac computed tomography (CT) and nuclear medicine tools, particularly ¹⁸F-fluorodeoxyglucose positron emission/CT.The choice of an appropriate treatment for each specific case is complex, both in terms of the selection of the appropriate agent and doses and durations of therapy as well as the possibility of using combined bactericidal antibiotic regimens in the initial phase and finalizing treatment at home in patients with good evolution with outpatient oral or parenteral antimicrobial therapies programs. A relevant proportion of patients will also require valve surgery during the active phase of treatment, the timing of which is extremely difficult to define. For all the above, the management of infective endocarditis requires a close collaboration of multidisciplinary endocarditis teams.

Patients with serious injection drug use related infections who experience patient directed discharges on oral antibiotics have high rates of antibiotic adherence but require multidisciplinary outpatient support for retention in care

Background

Persons who inject drugs (PWID) are frequently admitted for serious injection-related infections (SIRIs). Outcomes and adherence to oral antibiotics for PWID with patient-directed discharge (PDD) remain understudied.

Methods

We conducted a prospective multicenter bundled quality improvement project of PWID with SIRI at 3 hospitals in Missouri. All PWID with SIRI were offered multidisciplinary care while inpatient, including the option of addiction medicine consultation and medications for opioid use disorder (MOUD). All patients were offered oral antibiotics in the event of a PDD either at discharge or immediately after discharge through an infectious diseases telemedicine clinic. Additional support services included health coaches, a therapist, a case manager, free clinic follow-up, and medications in an outpatient bridge program. Patient demographics, comorbidities, 90-day readmissions, and substance use disorder clinic follow-up were compared between PWID with PDD on oral antibiotics and those who completed intravenous (IV) antibiotics using an as-treated approach.

Results

Of 166 PWID with SIRI, 61 completed IV antibiotics inpatient (37%), while 105 had a PDD on oral antibiotics (63%). There was no significant difference in 90-day readmission rates between groups (P = .819). For PWID with a PDD on oral antibiotics, 7.6% had documented nonadherence to antibiotics, 67% had documented adherence, and 23% were lost to follow-up. Factors protective against readmission included antibiotic and MOUD adherence, engagement with support team, and clinic follow-up.

Conclusions

PWID with SIRI who experience a PDD should be provided with oral antibiotics. Multidisciplinary outpatient support services are needed for PWID with PDD on oral antibiotics.

Infectious Complications of Injection Drug Use

The opioid overdose epidemic is one of the leading causes of death in adults. Its devastating effects have included not only a burgeoning overdose crisis but also multiple converging infectious diseases epidemics. The use of both opioids and other substances through intravenous (IV) administration places individuals at increased risks of infectious diseases ranging from invasive bacterial and fungal infections to human immunodeficiency virus (HIV) and viral hepatitis. In 2012, there were 530,000 opioid use disorder (OUD)-related hospitalizations in the United States (US), with $700 million in costs associated with OUD-related infections. The scale of the crisis has continued to increase since that time, with hospitalizations for injection drug use-related infective endocarditis (IDU-IE) increasing by as much as 12-fold from 2010 to 2015. Deaths from IDU-IE alone are estimated to result in over 7,260,000 years of potential life lost over the next 10 years. There have been high-profile injection-related HIV outbreaks, and injection drug use (IDU) is now the most common risk factor for hepatitis C virus (HCV). As this epidemic continues to grow, clinicians in all aspects of medical care are increasingly confronted with infectious complications of IDU. This review will describe the pathogenesis, clinical syndromes, epidemiology, and models of treatment for common infectious complications among persons who inject drugs (PWIDs).

Oral antibiotics for infective endocarditis: a clinical review

Current guidelines for management of infective endocarditis (IE) advise 4-6 weeks of IV antibiotics. This is based on historical data from animal models, which set a precedent for high peak serum antimicrobial levels, thought to be only achievable with IV therapy. However, there has been increasing recent interest in oral antibiotics as an alternative to prolonged parenteral therapy, not limited to treatment of IE. This review examines the theory behind parenteral antibiotic administration with reference to the MICs of relevant pathogens. By comparing published serum antimicrobial levels after oral and IV administration we suggest that safe levels of commonly used antibiotics can be achieved orally. We have then reviewed the literature to date on oral antibiotics for IE. The largest randomized controlled trial (RCT) in this area, the POET trial, concluded that oral therapy was non-inferior to prolonged IV therapy in stable patients with left-sided IE. Additionally, there have been two smaller RCTs published, as well as a number of observational studies over the last 50 years, utilizing a variety of different patient groups, methods and treatment strategies. This body of evidence gives weight to a potential shift in practice towards oral therapy, primarily as a step-down treatment. We conclude that pharmacological data offer theoretical reassurance for the safety of oral therapy. This is coupled with a growing evidence base for non-inferiority of oral antimicrobials compared with prolonged parenteral therapy in practice.

Long-term antibiotic therapy in patients with surgery-indicated not undergoing surgery infective endocarditis

BACKGROUND

To date, there is little information regarding management of patients with infective endocarditis (IE) that did not undergo an indicated surgery. Therefore, we aimed to evaluate prognosis of these patients treated with a long-term antibiotic treatment strategy, including oral long term suppressive antibiotic treatment in five referral centres with a multidisciplinary endocarditis team.

METHODS

This retrospective, multicenter study retrieved individual patient-level data from five referral centres in Spain. Among a total of 1797, 32 consecutive patients with IE were examined (median age 72 years; 78% males) who had not undergone an indicated surgery, but received long-term antibiotic treatment (LTAT) and were followed by a multidisciplinary endocarditis team, between 2011 and 2019. Primary outcomes were infection relapse and mortality during follow-up.

RESULTS

Among 32 patients, 21 had IE associated with prostheses. Of the latter, 8 had an ascending aorta prosthetic graft. In 24 patients, a switch to long-term oral suppressive antibiotic treatment (LOSAT) was considered. The median duration of LOSAT was 277 days. Four patients experienced a relapse during follow-up. One patient died within 60 days, and 12 patients died between 60 days and 3 years. However, only 4 deaths were related to IE.

CONCLUSIONS

The present study results suggest that a LTAT strategy, including LOSAT, might be considered for patients with IE that cannot undergo an indicated surgery. After hospitalization, they should be followed by a multidisciplinary endocarditis team.

Current Challenges in the Management of Infective Endocarditis

Infective endocarditis is a relatively rare, but deadly cause of sepsis, with an overall mortality ranging from 20 to 25% in most series. Although the classic clinical classification into syndromes of acute or subacute endocarditis have not completely lost their usefulness, current clinical forms have changed according to the profound epidemiological changes observed in developed countries. In this review, we aim to address the changing epidemiology of endocarditis, several recent advances in the understanding of the pathophysiology of endocarditis and endocarditis-triggered sepsis, new useful diagnostic tools as well as current concepts in the medical and surgical management of this disease. Given its complexity, the management of infective endocarditis requires the close collaboration of multidisciplinary endocarditis teams that must decide on the diagnostic approach; the appropriate initial treatment in the critical phase; the detection of patients needing surgery and the timing of this intervention; and finally the accurate selection of patients for out-of-hospital treatment, either at home hospitalization or with oral antibiotic treatment.

Outpatient Antimicrobial Therapy for Infective Endocarditis is Safe

Infective endocarditis (IE) is common and is associated with significant mortality, morbidity and health care burden. Outpatient antimicrobial therapy in carefully selected patients, supported by a multidisciplinary team is safe and beneficial for both the patient and the health care system. In this article, we review current literature of outpatient antimicrobial therapy in infective endocarditis and propose that most patients with IE should be considered and appropriate pathways developed to facilitate this.

Prevalence and predictors of aortic root abscess among patients with left-sided infective endocarditis: a cross-sectional comparative study

BACKGROUND

Aortic root abscess (ARA) is a major complication of infective endocarditis that is associated with increased morbidity and mortality. Limited data are present about patient characteristics and outcomes in this lethal disease. We aimed to study the clinical and echocardiographic characteristics of patients with ARA compared to patients with left-sided infective endocarditis without ARA. We included patients with a definite diagnosis of left-sided infective endocarditis according to modified Duke's criteria. The patients were classified into two groups according to the presence of ARA (ARA and NO-ARA groups). All the patients were studied regarding their demographic data, clinical characteristics, laboratory and imaging data, and complications.

RESULTS

We included 285 patients with left-sided infective endocarditis. The incidence of ARA was 21.4% (61 patients). Underlying heart disease, mechanical prosthesis, bicuspid aortic valve, and prior IE were significantly higher in ARA. The level of CRP was higher in ARA (p = 0.03). ARA group showed more aortic valve vegetations (73.8% vs. 37.1%, p < 0.001), more aortic paravalvular leakage (26.7% vs. 4.5%, p < 0.001), and less mitral valve vegetations (21.3% vs. 68.8%, p < 0.001). Logistic regression analysis showed that the odds of ARA increased in the following conditions: aortic paravalvular leak (OR 3.9, 95% CI 1.2-13, p = 0.03), mechanical prosthesis (OR 3.6, 95% CI 1.5-8.7, p = 0.005), aortic valve vegetations (OR 3.0, 95% CI 1.2-8.0, p = 0.02), and undetected organism (OR 2.3, 95% CI 1.1-4.6, p = 0.02), while the odds of ARA decreased with mitral valve vegetations (OR 0.2, 95% CI 0.08-0.5, p = 0.001). We did not find a difference between both groups regarding the incidence of major complications, including in-hospital mortality.

CONCLUSION

In our study, ARA occurred in one fifth of patients with left-sided IE. Patients with mechanical prosthesis, aortic paravalvular leakage, aortic vegetations, and undetected organisms had higher odds of ARA, while patients with mitral vegetations had lower odds of ARA.

A review of current treatment strategies for infective endocarditis

INTRODUCTION

Infective endocarditis is one of the most difficult-to-treat infectious diseases.

AREAS COVERED

We restricted this review to the anti-infective treatment of the main bacteria responsible for infective endocarditis, i.e. staphylococci, streptococci, enterococci, and Gram-negative bacilli, including HACEK. Specific topics of major interest in treatment strategy are covered as well, including empirical treatment, oral switch, and treatment duration. We searched in the MEDLINE database to identify relevant studies, trials, reviews, or meta-analyses until May 2020.

EXPERT OPINION

The use of aminoglycosides for the treatment of endocarditis has been dramatically reduced over the last 20 years. It should be administered once daily, and no longer than 2 weeks. For staphylococcal endocarditis, recent data reinforced the role of anti-staphylococcal penicillins, for methicillin-susceptible isolates (alternative, cefazolin), and vancomycin for methicillin-resistant isolates (alternative, daptomycin). For staphylococcal prosthetic-valve endocarditis, these treatments will be reinforced by the addition of gentamicin during the first 2 weeks, and rifampin throughout the whole treatment duration, i.e. 6 weeks. The optimal duration of antibacterial treatment is 4 weeks for most native valve endocarditis, and 6 weeks for prosthetic-valve endocarditis. The oral switch is safe in patients stabilized after the initial intravenous course.

A comparison of different antibiotic regimens for the treatment of infective endocarditis

BACKGROUND

Infective endocarditis is a microbial infection of the endocardial surface of the heart. Antibiotics are the cornerstone of treatment, but due to the differences in presentation, populations affected, and the wide variety of micro-organisms that can be responsible, their use is not standardised. This is an update of a review previously published in 2016.

OBJECTIVES

To assess the existing evidence about the clinical benefits and harms of different antibiotics regimens used to treat people with infective endocarditis.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase Classic and Embase, LILACS, CINAHL, and the Conference Proceedings Citation Index - Science on 6 January 2020. We also searched three trials registers and handsearched the reference lists of included papers. We applied no language restrictions.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) assessing the effects of antibiotic regimens for treating definitive infective endocarditis diagnosed according to modified Duke's criteria. We considered all-cause mortality, cure rates, and adverse events as the primary outcomes. We excluded people with possible infective endocarditis and pregnant women.

DATA COLLECTION AND ANALYSIS

Two review authors independently performed study selection, 'Risk of bias' assessment, and data extraction in duplicate. We constructed 'Summary of findings' tables and used GRADE methodology to assess the quality of the evidence. We described the included studies narratively.

MAIN RESULTS

Six small RCTs involving 1143 allocated/632 analysed participants met the inclusion criteria of this first update. The included trials had a high risk of bias. Three trials were sponsored by drug companies. Due to heterogeneity in outcome definitions and different antibiotics used data could not be pooled. The included trials compared miscellaneous antibiotic schedules having uncertain effects for all of the prespecified outcomes in this review. Evidence was either low or very low quality due to high risk of bias and very low number of events and small sample size. The results for all-cause mortality were as follows: one trial compared quinolone (levofloxacin) plus standard treatment (antistaphylococcal penicillin (cloxacillin or dicloxacillin), aminoglycoside (tobramycin or netilmicin), and rifampicin) versus standard treatment alone and reported 8/31 (26%) with levofloxacin plus standard treatment versus 9/39 (23%) with standard treatment alone; risk ratio (RR) 1.12, 95% confidence interval (CI) 0.49 to 2.56. One trial compared fosfomycin plus imipenem 3/4 (75%) versus vancomycin 0/4 (0%) (RR 7.00, 95% CI 0.47 to 103.27), and one trial compared partial oral treatment 7/201 (3.5%) versus conventional intravenous treatment 13/199 (6.53%) (RR 0.53, 95% CI 0.22 to 1.31). The results for rates of cure with or without surgery were as follows: one trial compared daptomycin versus low-dose gentamicin plus an antistaphylococcal penicillin (nafcillin, oxacillin, or flucloxacillin) or vancomycin and reported 9/28 (32.1%) with daptomycin versus 9/25 (36%) with low-dose gentamicin plus antistaphylococcal penicillin or vancomycin; RR 0.89, 95% CI 0.42 to 1.89. One trial compared glycopeptide (vancomycin or teicoplanin) plus gentamicin with cloxacillin plus gentamicin (13/23 (56%) versus 11/11 (100%); RR 0.59, 95% CI 0.40 to 0.85). One trial compared ceftriaxone plus gentamicin versus ceftriaxone alone (15/34 (44%) versus 21/33 (64%); RR 0.69, 95% CI 0.44 to 1.10), and one trial compared fosfomycin plus imipenem versus vancomycin (1/4 (25%) versus 2/4 (50%); RR 0.50, 95% CI 0.07 to 3.55). The included trials reported adverse events, the need for cardiac surgical interventions, and rates of uncontrolled infection, congestive heart failure, relapse of endocarditis, and septic emboli, and found no conclusive differences between groups (very low-quality evidence). No trials assessed quality of life.

AUTHORS' CONCLUSIONS

This first update confirms the findings of the original version of the review. Limited and low to very low-quality evidence suggests that the comparative effects of different antibiotic regimens in terms of cure rates or other relevant clinical outcomes are uncertain. The conclusions of this updated Cochrane Review were based on few RCTs with a high risk of bias. Accordingly, current evidence does not support or reject any regimen of antibiotic therapy for the treatment of infective endocarditis.

Evaluation of a Paradigm Shift From Intravenous Antibiotics to Oral Step-Down Therapy for the Treatment of Infective Endocarditis: A Narrative Review

IMPORTANCE

The requirement of prolonged intravenous antibiotic courses to treat infective endocarditis (IE) is a time-honored dogma of medicine. However, numerous antibiotics are now available that achieve adequate levels in the blood after oral administration to kill bacteria. Moreover, prolonged intravenous antibiotic regimens are associated with high rates of adverse events. Accordingly, recent studies of oral step-down antibiotic treatment have stimulated a reevaluation of the need for intravenous-only therapy for IE.

OBSERVATIONS

PubMed was reviewed in October 2019, with an update in February 2020, to determine whether evidence supports the notion that oral step-down antibiotic therapy for IE is associated with inferior outcomes compared with intravenous-only therapy. The search identified 21 observational studies evaluating the effectiveness of oral antibiotics for treating IE, typically after an initial course of intravenous therapy; none found such oral step-down therapy to be inferior to intravenous-only therapy. Multiple studies described an improved clinical cure rate and an improved mortality rate among patients treated with oral step-down vs intravenous-only antibiotic therapy. Three randomized clinical trials also demonstrated that oral step-down antibiotic therapy is at least as effective as intravenous-only therapy in right-sided, left-sided, or prosthetic valve IE. In the largest trial, at 3.5 years of follow-up, patients randomized to receive oral step-down antibiotic therapy had a significantly improved cure rate and mortality rate compared with those who received intravenous-only therapy.

CONCLUSIONS AND RELEVANCE

This review found ample data demonstrating the therapeutic effectiveness of oral step-down vs intravenous-only antibiotic therapy for IE, and no contrary data were identified. The use of highly orally bioavailable antibiotics as step-down therapy for IE, after clearing bacteremia and achieving clinical stability with intravenous regimens, should be incorporated into clinical practice.

Partial oral antibiotic therapy is non-inferior to intravenous therapy in non-critically ill patients with infective endocarditis : Review and meta-analysis

Background

Antimicrobial therapy is a cornerstone in the treatment of infective endocarditis (IE). Typically, intravenous (i.v.) therapy is given for 6 weeks or longer, leading to prolonged hospital stays and high costs. Several trials evaluating the efficacy of partial oral therapy (POT) have been published. This article aimed to review and meta-analyze studies comparing i.v. therapy versus POT in non-critically ill patients suffering from IE.

Methods

A structured database search (based on PRISMA guidelines) regarding POT versus i.v. therapy in IE was conducted using PubMed/Medline. Primary endpoint was all-cause mortality and a secondary endpoint IE relapse. Risk rates were calculated using a random effects model (DerSimonian and Laird). Heterogeneity was assessed using the I² statistics.

Results

After screening 1848 studies at title and abstract levels, 4 studies were included. A total of 765 patients suffered from primary left-sided IE, whereas right-sided IE was observed in 72 patients. Mortality rates were lower in POT versus i.v. therapy (risk ratio [RR] 0.38, 95% confidence interval, confidence interval [CI] 0.20–0.74; p = 0.004; I² 0%). IE relapse rates were similar (RR 0.63, 95% CI 0.29–1.37; p = 0.24; I² 0%).

Conclusion

Data comparing POT with standard care in IE is limited and to date only one sufficiently powered stand-alone trial exists to support its use. In this meta-analysis POT was non-inferior to i.v. therapy with respect to mortality and IE relapse in non-critically ill patients suffering from both left-sided and right-sided IE. These findings indicate that POT is a feasible treatment strategy in selected patients suffering from IE but further validation in future studies will be required.

Complications of peripheral venous catheters: The need to propose an alternative route of administration

Use of peripheral venous catheters (PVCs) is very common in hospitals. According to the literature, after a visit to the emergency department >75% of hospitalised patients carry a PVC, among which almost 50% are useless. In this study, the presence and complications of PVCs in an infectious diseases (ID) unit of a French tertiary-care university hospital were monitored. A total of 614 patients were prospectively included over a 6-month period. Among the 614 patients, 509 (82.9%) arrived in the ID unit with a PVC, of which 260 (51.1%) were judged unnecessary and were removed as soon as the patients were examined by the ID team. More than one-half of PVCs were removed within 24 h in the unit (308/509; 60.5%). PVCs were complicated for 65 (12.8%) of the 509 patients, with complications including extravasation, cutaneous necrosis, lymphangitis, phlebitis, tearing off the patient, superficial venous thrombosis and arthritis. We must therefore continue to search for unjustified PVC insertion. Alternatives to the intravenous administration route must be proposed, such as subcutaneous infusion or oral antibiotic therapy.

Outpatient Parenteral Antibiotic Treatment for Infective Endocarditis: A Prospective Cohort Study From the GAMES Cohort

BACKGROUND

Outpatient parenteral antibiotic treatment (OPAT) has proven efficacious for treating infective endocarditis (IE). However, the 2001 Infectious Diseases Society of America (IDSA) criteria for OPAT in IE are very restrictive. We aimed to compare the outcomes of OPAT with those of hospital-based antibiotic treatment (HBAT).

METHODS

Retrospective analysis of data from a multicenter, prospective cohort study of 2000 consecutive IE patients in 25 Spanish hospitals (2008-2012) was performed.

RESULTS

A total of 429 patients (21.5%) received OPAT, and only 21.7% fulfilled IDSA criteria. Males accounted for 70.5%, median age was 68 years (interquartile range [IQR], 56-76), and 57% had native-valve IE. The most frequent causal microorganisms were viridans group streptococci (18.6%), Staphylococcus aureus (15.6%), and coagulase-negative staphylococci (14.5%). Median length of antibiotic treatment was 42 days (IQR, 32-54), and 44% of patients underwent cardiac surgery. One-year mortality was 8% (42% for HBAT; P < .001), 1.4% of patients relapsed, and 10.9% were readmitted during the first 3 months after discharge (no significant differences compared with HBAT). Charlson score (odds ratio [OR], 1.21; 95% confidence interval [CI], 1.04-1.42; P = .01) and cardiac surgery (OR, 0.24; 95% CI, .09-.63; P = .04) were associated with 1-year mortality, whereas aortic valve involvement (OR, 0.47; 95% CI, .22-.98; P = .007) was the only predictor of 1-year readmission. Failing to fulfill IDSA criteria was not a risk factor for mortality or readmission.

CONCLUSIONS

OPAT provided excellent results despite the use of broader criteria than those recommended by IDSA. OPAT criteria should therefore be expanded.

Current Evidence on Oral Antibiotics for Infective Endocarditis: A Narrative Review

Infective endocarditis (IE) continues to be associated with high morbidity and mortality, even when treated with optimal antibiotic regimens. The selection of treatment depends on the causative pathogen, its antibiotic susceptibility profile, local and systemic complications and the presence of prosthetic materials or devices. Standard therapy typically involves 4–6 weeks of intravenous (IV) bactericidal therapy. However, there are instances in which IV antibiotic administration may be challenging due to cost, complications of IV access, adverse side-effects of the medication or concerns for misuse of the IV line. Current clinical guidance from the American Heart Association and the European Society of Cardiology cite scenarios where oral antibiotics can be considered for treatment of IE, though these situations are relatively infrequent and data to show their non-inferiority limited. Recently, a well-designed randomized clinical study reported favorable outcomes for partial oral antimicrobial therapy regimens given to patients with staphylococcal, streptococcal and enterococcal IE deemed clinically stable and without complications such as perivalvular abscess. Oral antibiotics, usually given in combination, were selected by infectious disease providers for their favorable pharmacologic properties and predicted bactericidal activity. There was a careful selection of patients who were transitioned to oral regimens. Before recommending routine use of oral antibiotics in the care of patients with IE, additional studies that better define eligible patients and that use regimens available in the countries that adopt this practice should be performed. If further studies confirm non-inferior outcomes with partial oral antibiotics for the treatment of IE, medical treatment could be delivered in a simpler, more costeffective manner, and likely with lower rates of adverse side-effects.

Viridans streptococcal infective endocarditis associated with fixed orthodontic appliance managed surgically by mitral valve plasty: A case report

RATIONALE

Streptococcus viridans, a heterogeneous group of alpha-hemolytic streptococci, is part of the normal flora of the mouth, usually responsible for dental caries (Streptococcus mutans, Streptococcus sanguinis), and pericoronitis, as well as for subacute infective endocarditis. They are responsible for 40-60% of the endocarditis cases occurring on the normal valves, especially in male patients and over 45 years of age. A change in the bacterial flora of the oral cavity is taking part after orthodontic fixed appliances are introduced into the oral cavity, change that is associated with an increased concentration of the acidogenic bacteria. Bacteraemia is the consequence of oral cavity infections, the association of infective endocarditis with fixed orthodontic appliance, as it has been described by us for the first time, caused by Abiotrophia defectiva.

PATIENT CONCERNS

We present the case of a female Caucasian patient, aged 22 years, who developed infective endocarditis with Streptococcus viridans associated with fixed orthodontic appliance, located on the mitral valve, without previous cardiac pathology, and the therapeutic difficulties associated with allergic reactions (to vancomycin, and spironolactone).

DIAGNOSES

Repetitive haemocultures were positive with Streptococcus viridans, while transthoracic echography revealed a severe mitral failure through anteromedial segment of the anterior mitral valve leaf prolapse with eccentric jet to the posterior wall.

INTERVENTIONS

During hospitalization, the decision to undergo surgical intervention was taken after obtaining negative haemocultures. The patient underwent surgically intervention, and a mitral valve plasty with insertion of neochords was performed.

OUTCOMES

Intraoperative and subsequently post-discharge transesophageal echography, highlighted normofunctional mitral plasty with a remaining regurgitation grade I-II of IV, with good openness, minor tricuspid regurgitation, and mild pulmonary hypertension.

LESSONS

Endocarditis with oral streptococci associated with fixed orthodontic appliance seems to be not so unlikely even in young or without previous cardiac pathology patients, requiring attention in identifying possible pre-existing cardiac conditions like mitral valve prolapse with clinical and echographic monitoring of such cases. Educating and motivating the patient to observe the oral hygiene represent key steps for an optimal oral health during orthodontic treatment. Mechanical tooth cleaning helps maintaining a good oral hygiene during fixed orthodontics and decreasing the oral health risks.

A comparison of different antibiotic regimens for the treatment of infective endocarditis

BACKGROUND

Infective endocarditis is a microbial infection of the endocardial surface of the heart. Antibiotics are the cornerstone of treatment, but their use is not standardised, due to the differences in presentation, populations affected and the wide variety of micro-organisms that can be responsible.

OBJECTIVES

To assess the existing evidence about the clinical benefits and harms of different antibiotics regimens used to treat people with infective endocarditis.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE Classic and EMBASE, LILACS, CINAHL and the Conference Proceedings Citation Index on 30 April 2015. We also searched three trials registers and handsearched the reference lists of included papers. We applied no language restrictions.

SELECTION CRITERIA

We included randomised controlled trials assessing the effects of antibiotic regimens for treating possible infective endocarditis diagnosed according to modified Duke's criteria. We considered all-cause mortality, cure rates and adverse events as the primary outcomes. We excluded people with possible infective endocarditis and pregnant women.

DATA COLLECTION AND ANALYSIS

Three review authors independently performed study selection, 'Risk of bias' assessment and data extraction in duplicate. We constructed 'Summary of findings' tables and used GRADE methodology to assess the quality of studies. We described the included studies narratively.

MAIN RESULTS

Four small randomised controlled trials involving 728 allocated/224 analysed participants met our inclusion criteria. These trials had a high risk of bias. Drug companies sponsored two of the trials. We were unable to pool the data due to the heterogeneity in outcome definitions and the different antibiotics used.The included trials compared the following antibiotic schedules. The first trial compared quinolone (levofloxacin) plus standard treatment (anti-staphylococcal penicillin (cloxacillin or dicloxacillin), aminoglycoside (tobramycin or netilmicin) and rifampicin) versus standard treatment alone reporting uncertain effects on all-cause mortality (8/31 (26%) with levofloxacin plus standard treatment versus 9/39 (23%) with standard treatment alone; RR 1.12, 95% CI 0.49 to 2.56, very low quality evidence). The second trial compared daptomycin versus low-dose gentamicin plus an anti-staphylococcal penicillin (nafcillin, oxacillin or flucloxacillin) or vancomycin. This showed uncertain effects in terms of cure rates (9/28 (32.1%) with daptomycin versus 9/25 (36%) with low-dose gentamicin plus anti-staphylococcal penicillin or vancomycin, RR 0.89 95% CI 0.42 to 1.89; very low quality evidence). The third trial compared cloxacillin plus gentamicin with a glycopeptide (vancomycin or teicoplanin) plus gentamicin. In participants receiving gentamycin plus glycopeptide only 13/23 (56%) were cured versus 11/11 (100%) receiving cloxacillin plus gentamicin (RR 0.59, 95% CI 0.40 to 0.85; very low quality evidence). The fourth trial compared ceftriaxone plus gentamicin versus ceftriaxone alone and found no conclusive differences in terms of cure (15/34 (44%) with ceftriaxone plus gentamicin versus 21/33 (64%) with ceftriaxone alone, RR 0.69, 95% CI 0.44 to 1.10; very low quality evidence).The trials reported adverse events, need for cardiac surgical interventions, uncontrolled infection and relapse of endocarditis and found no conclusive differences between comparison groups (very low quality evidence). No trials assessed septic emboli or quality of life.

AUTHORS' CONCLUSIONS

Limited and very low quality evidence suggested that there were no conclusive differences between antibiotic regimens in terms of cure rates or other relevant clinical outcomes. However, because of the very low quality evidence, this needs confirmation. The conclusion of this Cochrane review was based on randomised controlled trials with high risk of bias. Accordingly, current evidence does not support or reject any regimen of antibiotic therapy for treatment of infective endocarditis.

The history and evolution of outpatient parenteral antibiotic therapy (OPAT)

Outpatient parenteral antibiotic therapy (OPAT) is now a widely accepted and safe therapeutic option for carefully selected patients. Benefits include cost savings and improved patient satisfaction; risks include failure to adhere to care, unexpected changes in the underlying infection, and adverse drug and intravenous access events. We report on our 40-year experience with OPAT in a single healthcare system in the USA and highlight OPAT developments in several countries. We compared data on patients treated in our programme over two time periods: Period 1 from 1978 to 1990; and Period 2, calendar year 2014. In Period 2 paediatric patients were excluded. Between Periods 1 and 2, changes included an almost three-fold increase in the number of patients treated per year (80 vs. 229), treatment of more patients with severe orthopaedic-related infections (20% vs. 38%), a marked increase in the use of peripherally inserted central catheters to administer antibiotics (20% vs. 98%), a shorter duration of inpatient stay and a longer duration of OPAT (13 days vs. 24 days). Other changes in Period 2 included treatment of 20% of patients without antecedent hospitalisation, and use of carbapenems rather than cephalosporins as the most frequently administered agents. OPAT was safe, with rehospitalisation rates of 6% and 1% in Periods 1 and 2, respectively. We recommend increased access to structured OPAT teams and the development of standard definitions and criteria for important outcome measures (e.g. clinical 'cure' and unplanned hospital re-admissions). These steps are critical for patient safety and financial stewardship of resources.

Oral antibiotic therapy for the treatment of infective endocarditis: a systematic review

Background

The role of oral antibiotic therapy in treating infective endocarditis (IE) is not well established.

Methods

We searched MEDLINE, EMBASE and Scopus for studies in which oral antibiotic therapy was used for the treatment of IE.

Results

Seven observational studies evaluating the use oral beta-lactams (five), oral ciprofloxacin in combination with rifampin (one), and linezolid (one) for the treatment of IE caused by susceptible bacteria reported cure rates between 77% and 100%. Two other observational studies using aureomycin or sulfonamide, however, had failure rates >75%. One clinical trial comparing oral amoxicillin versus intravenous ceftriaxone for streptococcal IE reported 100% cure in both arms but its reporting had serious methodological limitations. One small clinical trial (n = 85) comparing oral ciprofloxacin and rifampin versus conventional intravenous antibiotic therapy for uncomplicated right-sided S. aureus IE in intravenous drug users (IVDUs) reported cure rates of 89% and 90% in each arm, respectively (P =0.9); however, drug toxicities were more common in the latter group (62% versus 3%; P <0.01). Major limitations of this trial were lack of allocation concealment and blinding at the delivery of the study drug(s) and assessment of outcomes.

Conclusion

Reported cure rates for IE treated with oral antibiotic regimens vary widely. The use of oral ciprofloxacin in combination with rifampin for uncomplicated right-sided S. aureus IE in IVDUs is supported by one small clinical trial of relatively good quality and could be considered when conventional IV antibiotic therapy is not possible.

[Daptomycin in outpatient antimicrobial parenteral therapy]

Daptomycin is a cyclic lipopeptide with a rapid bactericidal effect against Gram-positive bacteria. The pharmacokinetic properties of this drug allow once-daily intravenous infusion as the best posology (including a 2-minute bolus). Because of its ease of administration and excellent safety profile, daptomycin is a first-line agent for use as outpatient antimicrobial parenteral therapy (OPAT). The best evidence supporting this indication exists for the treatment of complicated and uncomplicated skin and soft tissue infections, as well as osteoarticular infections caused by Gram-positive bacteria. For the remaining indications, the use of daptomycin as OPAT should be analyzed in each patient. Information from the EUCORE Registry in Spain indicates that daptomycin has high rates of treatment success in both hospitalized patient and in those included in OPAT programs.

Efficacy and safety of outpatient parenteral antibiotic therapy for infective endocarditis: a ten-year prospective study

BACKGROUND

The length of treatment of infective endocarditis (IE) with parenteral antibiotics varies from 2 to 6 weeks. Although several studies indicate that outpatient parenteral antibiotic treatment (OPAT) could be safe for uncomplicated viridans-group streptococci (VGS) IE, the experience in Spain is limited and data on other types of endocarditis and OPAT are scarce worldwide.

METHODS

Prospective single center study of a cohort including all patients with IE admitted to the Hospital Clinic of Barcelona OPAT program from January 1997 to December 2006.

RESULTS

During the study period, 392 consecutive episodes of IE in non-drug abusers were attended to. Of these, 73 episodes (42 native-valve, 23 prosthetic-valve, and 8 pacemaker-lead) were admitted to the OPAT program (19%). The percentage of inclusion was higher for viridans group streptococci (VGS) or Streptococcus bovis (S. bovis) IE (32% of all VGS or S. bovis IE episodes diagnosed vs. 14% of the remaining etiologies, P<.001). Twelve patients (16%) were readmitted due to complications, of which 3 died (4%). Glycopeptides use was the only predictor factor of hospital readmission (OR 4.5, 95% confidence interval 1.2; 16.8, P=.026). No differences in OPAT outcome were found between VGS plus S. bovis IE and Staphylococcus aureus (S. aureus) plus coagulase-negative staphylococci IE. Patients spent a median of 17 day on OPAT (interquartile range 11-26.5), which enabled 1,466 days of hospital stay to be saved.

CONCLUSIONS

These data suggest that OPAT for IE may be a safe and effective therapeutic approach in the treatment of selected patients with types of endocarditis other than uncomplicated VGS or S. bovis endocarditis, although patients taking glycopeptides need close clinical OPAT monitoring.

Outpatient parenteral antibiotic therapy

Clinical studies have shown that outpatient administration of parenteral antibiotics is sage, cost-effective and practical. The development of new antibiotics with prolonged half-lives, such as ceftriaxone or cefotetan, has facilitated outpatient parenteral antibiotic therapy (OPAT). Good OPAT management requires coordination of physicians, nurses, pharmacists and health care administrators, and the establishment of firm guidelines. A variety of infections can be treated through OPAT, including osteomyelitis and soft tissue infections, chronic urinary tract infections, and ear, nose and throat infections.

Is hospital-in-the-home (HITH) treatment of bacterial endocarditis safe and effective?

Although serious infections such as bacterial endocarditis (BE) are being increasingly treated with parenteral antibiotics via Hospital-in-the-Home (HITH) programmes in Australia, there are few published data to confirm the safety and efficacy of this treatment modality, especially among patients with BE due to pathogens other than streptococci. In a 12-month prospective, multi-site study we assessed HITH treatment outcomes for all cases of BE. Among the 40 BE cases (29 'definite', 11 'possible'; Duke criteria) caused by a range of pathogens (16 staphylococci spp., 11 streptococci, 4 other, 9 culture-negative), cure was achieved in 37 (93%) cases. BE due to Staphylococcus aureus was significantly associated with an inferior outcome (p =0.046). Adverse events were relatively common (9/40), but most were not severe and were managed with continuation of HITH care. BE can be safely managed via HITH, but particular care in patient selection is necessary, especially for cases due to S. aureus.

Swedish guidelines for diagnosis and treatment of infective endocarditis

Swedish guidelines for diagnosis and treatment of infective endocarditis (IE) by consensus of experts are based on clinical experience and reports from the literature. Recommendations are evidence based. For diagnosis 3 blood cultures should be drawn; chest X-ray, electrocardiogram, and echocardiography preferably transoesophageal should be carried out. Blood cultures should be kept for 5 d and precede intravenous antibiotic therapy. In patients with native valves and suspicion of staphylococcal aetiology, cloxacillin and gentamicin should be given as empirical treatment. If non-staphylococcal etiology is most probable, penicillin G and gentamicin treatment should be started. In patients with prosthetic valves treatment with vancomycin, gentamicin and rifampicin is recommended. Patients with blood culture negative IE are recommended penicillin G (changed to cefuroxime in treatment failure) and gentamicin for native valve IE and vancomycin, gentamicin and rifampicin for prosthetic valve IE, respectively. Isolates of viridans group streptococci and enterococci should be subtyped and MIC should be determined for penicillin G and aminoglycosides. Antibiotic treatment should be chosen according to sensitivity pattern given 2-6 weeks intravenously. Cardiac valve surgery should be considered early, especially in patients with left-sided IE and/or prosthetic heart valves. Absolute indications for surgery are severe heart failure, paravalvular abscess, lack of response to antibiotic therapy, unstable prosthesis and multiple embolies. Follow-up echocardiography should be performed on clinical indications.

German guidelines for the diagnosis and management of infective endocarditis

This Gudelines are the translation of the German Guidelines for the Diagnosis and Management of Infective Endocarditis, which were prepared by the Working Group on Infective Endocarditis of the Paul-Ehrlich-Society and the German Society for Cardiology, Heart, and Circulatory Research in cooperation with the Deutsche Gesellschaft für Thorax-, Herz und Gefässchirurgie (DGTHG; German Society for Thorax-, Cardiac-, and Vascular Surgery), the Deutsche Gesellschaft für Infektiologie (DGI; German Society for Infectious Diseases), the Deutsche Gesellschaft für Internistische Intensivmedizin und Notfallmedizin (DGIIN; German Society for Internal Intensive Care Medicin and Emergency Medicine), the Deutsche Gesellschaft für Hygiene und Mikrobiologie (DGHM; German Society for Hygiene and Microbiology) and the Deutsche Gesellschaft für Innere Medizin (DGIM; German Society for Internal Medicine) (Naber CK et al. [S2 Guideline for diagnosis and therapy of infectious endocarditis] Z Kardiol. 2004;93:1005-21). The Guidelines provide recommendations for the diagnosis and management of infective endocarditis.

Antimicrobial treatment of infective endocarditis caused by viridans streptococci highly susceptible to penicillin: historic overview and future considerations

In this article we present the path that led to current concepts regarding antimicrobial treatment of endocarditis caused by viridans streptococci highly susceptible to penicillin. Early treatment trials indicate that some patients with subacute endocarditis can be cured with shorter treatment duration than currently advised by international guidelines. Also, high-dose antibiotics, as recommended today, have a predominantly pharmacokinetic and pharmacodynamic rationale that is based mostly on experimental animal studies. Shortening antimicrobial treatment in select patients with endocarditis would be of great benefit. As yet there are no predictors of cure that can be used to individualize treatment duration in patients with bacterial endocarditis.

The role of aminoglycosides in combination with a beta-lactam for the treatment of bacterial endocarditis: a meta-analysis of comparative trials

BACKGROUND

The addition of an aminoglycoside to a beta-lactam for the treatment of patients with infective endocarditis has been supported by data from laboratory and animal studies.

PURPOSE

We sought to review the evidence from the available comparative clinical trials regarding the role of aminoglycosides in combination with a beta-lactam for the treatment of bacterial endocarditis caused by Gram-positive cocci.

DATA SOURCES

The studies for our meta-analysis were retrieved from searches of the PubMed and Cochrane Central Register of Controlled Trials databases, as well as from the references cited in relevant articles. No limits were set regarding the language and date of publication of the studies.

STUDY SELECTION

Included studies were prospective studies that provided comparative data regarding the effectiveness of the treatment and/or mortality in patients receiving monotherapy with a beta-lactam or beta-lactam/aminoglycoside combination therapy.

DATA EXTRACTION

Two independent reviewers performed the literature search, study selection and extraction of data from relevant studies.

DATA SYNTHESIS

No clinical trial comparing beta-lactam monotherapy with beta-lactam/aminoglycoside combination therapy for the treatment of enterococcal endocarditis was found. We performed a meta-analysis of five available comparative trials [four randomized controlled trials (RCTs) and one comparative prospective trial], which included 261 patients with bacterial endocarditis in native valves due to Staphylococcus aureus (four studies) or streptococci of the viridans group (one study). There was no statistically significant difference between beta-lactam monotherapy and beta-lactam/aminoglycoside combination therapy regarding mortality [odds ratio (OR) = 0.59, 95% confidence interval (95% CI) = 0.21-1.66], treatment success (OR = 1.25, 95% CI = 0.49-3.05), treatment success without surgery (OR = 1.66, 95% CI = 0.64-4.30) or relapse of endocarditis (OR = 0.79, 95% CI = 0.15-4.29). Nephrotoxicity was less common in the beta-lactam monotherapy arm than in the beta-lactam/aminoglycoside combination therapy arm (OR = 0.38, 95% CI = 0.16-0.88, P = 0.024). No difference between the two treatment arms was found in subanalyses of the four studies that included only patients with staphylococcal infections in terms of mortality (OR = 0.69, 95% CI = 0.26-1.86, fixed effects model), treatment success (OR = 1.27, 95% CI = 0.47-3.43, fixed effects model) or relapse (OR = 0.76, 95% CI = 0.12-4.92, fixed effects model).

LIMITATIONS

The relatively small number of available comparative trials was the major limitation of this meta-analysis.

CONCLUSIONS

The limited evidence from the available prospective comparative studies does not offer support for the addition of an aminoglycoside to beta-lactam treatment of patients with endocarditis caused by Gram-positive cocci. A large multicentre RCT is necessary to reach a definitive conclusion on this issue.

Guidelines for the antibiotic treatment of endocarditis in adults: report of the Working Party of the British Society for Antimicrobial Chemotherapy

The BSAC Guidelines on Endocarditis were last published in 1998. The Guidelines presented here have been updated and extended to reflect changes in both the antibiotic resistance characteristics of causative organisms and the availability of new antibiotics. Randomized, controlled trials suitable for the development of evidenced-based guidelines in this area are still lacking, and therefore a consensus approach has again been adopted. The Guidelines cover diagnosis and laboratory testing, suitable antibiotic regimens and causative organisms. Special emphasis is placed on common causes of endocarditis, such as streptococci and staphylococci, however, other bacterial causes (such as enterococci, HACEK organisms, Coxiella and Bartonella) and fungi are considered. The special circumstances of prosthetic endocarditis are discussed.

Combination antibiotic therapy for infective endocarditis

Despite the availability of new and potent antibiotics, modern echocardiography, and advanced surgical techniques, infective endocarditis (IE) is still associated with high morbidity and mortality rates. Use of synergistic antibiotic combinations is an appealing way to optimize therapy for IE. This review focuses on evidence-based recommendations for combination antimicrobial therapy for IE due to the most common etiologic pathogens. Few proven synergistic approaches for the treatment of IE have been globally demonstrated via in vitro models, experimental IE models, and human clinical trials, except for IE due to enterococci. Novel approaches, such as short-course aminoglycoside therapy and double-beta-lactam combination therapy, appear to be promising for treatment of enterococcal IE. Short-course combination therapy involving agents with activity against the cell wall (CWAs) and aminoglycosides is highly effective for IE caused by viridans group streptococci. Although synergistic combination therapy with CWAs-aminoglycosides remains widely used by clinicians for Staphylococcus aureus IE, few definitive human data exist that demonstrate the clinical benefit of such an approach.

Outpatient Management of Infective Endocarditis

Because of unique host defense characteristics of the endocardium, successful therapy for infective endocarditis (IE) has necessitated bactericidal antimicrobial agents, generally administered in high doses for prolonged periods of time. This has required therapy in the hospital setting. However, in recent years, it has become apparent that outpatient therapy is feasible if appropriate agents can be administered at home, for example, using either home parenteral therapy or oral preparations. Over the past few decades, there has been a trend toward reducing inpatient reimbursement for various conditions, including serious infections. The decision to treat IE on an outpatient basis is made more easily if based on previous published experience. Published reports have concluded that outpatient therapy is more appropriate for "uncomplicated" IE caused by relatively susceptible microorganisms. The purpose of this paper is to review data describing the results of management of IE in the outpatient setting.