Community-based outpatient parenteral antimicrobial therapy (CoPAT) for Staphylococcus aureus bacteraemia with or without infective endocarditis: analysis of the randomized trial comparing daptomycin with standard therapy

Safety and efficacy of outpatient parenteral antimicrobial therapy: A systematic review and meta-analysis of randomized clinical trials

BACKGROUND

Outpatient parenteral antimicrobial therapy (OPAT) offers an alternative to inpatient (hospital bed-based) treatment of infections that require intravenous administration of antimicrobials. This meta-analysis aimed to summarise the evidence available from randomised controlled trials (RCTs) regarding the efficacy and safety of OPAT compared to inpatient parenteral antimicrobial therapy.

METHODS

We searched the Cochrane Library, MEDLINE, Embase, PubMed, and Web of Sciences databases for RCTs comparing outpatient versus inpatient parenteral antimicrobial therapy. We included studies without restrictions on language or publication year. Eligibility was reviewed independently by two assessors, and data extraction was cross validated. We evaluated bias risk via the Cochrane tool and determined the evidence certainty using GRADE. Meta-analysis was conducted using a random effects model. The protocol of this review was registered on PROSPERO (CRD42023460389).

RESULT

Thirteen RCTs, involving 1,310 participants were included. We found no difference in mortality (Risk Ratio [RR] 0.54, 95% Confidence Interval [CI] 0.23 to 1.26; P = 0.93), treatment failure (RR 1.0, CI 0.59 to 1.72; P = 0.99), adverse reaction related to antimicrobials (RR 0.89, CI 0.69 to 1.15; P = 0.38), and administration device (RR 0.58, CI 0.17 to 1.98; P = 0.87) between outpatient and inpatient parenteral antimicrobial therapy. The overall body of evidence had a low level of certainty.

CONCLUSION

Existing evidence suggests OPAT is a safe and effective alternative to inpatient treatment. Further RCTs are warranted for a thorough comparison of inpatient and outpatient parenteral antimicrobial therapy with a high level of certainty.

Oritavancin as sequential therapy for Gram-positive bloodstream infections

BACKGROUND

Oritavancin, a long-acting lipoglycopeptide approved for use in acute bacterial skin and skin structure infections, has limited data evaluating use in serious infections due to Gram-positive organisms. We aimed to assess the effectiveness and safety of oritavancin for consolidative treatment of Gram-positive bloodstream infections (BSI), including infective endocarditis (IE).

METHODS

We conducted a retrospective cohort study evaluating adult patients admitted to University of Colorado Hospital from March 2016 to January 2022 who received ≥ 1 oritavancin dose for treatment of Gram-positive BSI. Patients were excluded if the index culture was drawn at an outside facility or were > 89 years of age. The primary outcome was a 90-day composite failure (clinical or microbiological failure) in those with 90-day follow-up. Secondary outcomes included individual components of the primary outcome, acute kidney injury (AKI), infusion-related reactions (IRR), and institutional cost avoidance.

RESULTS

Overall, 72 patients were included. Mean ± SD age was 54 ± 16 years, 61% were male, and 10% had IE. Organisms most commonly causing BSI were Staphylococcus aureus (68%, 17% methicillin-resistant), followed by Streptococcus spp. (26%), and Enterococcus spp. (10%). Patients received standard-of-care antibiotics before oritavancin for a median (IQR) of 11 (5-17) days. Composite failure in the clinically evaluable population (n = 64) at 90-days occurred in 14% and was composed of clinical and microbiological failure, which occurred in 14% and 5% of patients, respectively. Three patients (4%) experienced AKI after oritavancin, and two (3%) experienced an IRR. Oritavancin utilization resulted in earlier discharge for 94% of patients corresponding to an institutional cost-avoidance of $3,055,804 (mean $44,938/patient) from 1,102 hospital days saved (mean 16 days/patient).

CONCLUSIONS

The use of oritavancin may be an effective sequential therapy for Gram-positive BSI to facilitate early discharge resulting in institutional cost avoidance.

Substance use disorder-associated infections' treatment with dalbavancin enabling outpatient transition (SUDDEN OUT) - an investigator-initiated single-arm unblinded prospective cohort study

Background

Severe gram-positive infections are frequent in people who inject drugs, and successful completion of treatment presents unique challenges in this population.

Objectives

We aimed to evaluate the feasibility of a long-acting antibiotic, dalbavancin, as an alternative to standard-of-care antibiotics for severe infections due to vancomycin-susceptible pathogens requiring ⩾2 weeks of therapy.

Design

We designed an investigator-initiated single-arm unblinded prospective cohort study to evaluate the safety and efficacy of an early switch to dalbavancin in two doses administered 1 week apart.

Methods

We screened patients admitted with bloodstream infection, osteomyelitis, septic arthritis, infective endocarditis or deep abscesses, and comorbid substance use disorder (SUD) for eligibility. Consenting patients were switched to dalbavancin within 7 days from their index culture. They were monitored in the hospital for efficacy and safety of the treatment until the second dose of dalbavancin 7 days later and then discharged if stable. Study participants were evaluated with a decision support engine for a hypothetical appropriate level of care regarding their SUD after discharge. Their follow-up was planned for 12 months from the index culture, either in-person or via telehealth/telephone.

Results

The enrollment was terminated early due to significant loss-to-follow-up. In all, 11 patients were enrolled, 4 completed 12 months of follow-up, 2 completed 8 months of follow-up, and 1 was seen once after discharge. The remaining five patients were lost to follow-up immediately after discharge. All 11 patients continued to improve after switching to dalbavancin between the first and second doses. There were two per-protocol failures of treatment. Dalbavancin was well tolerated, though some adverse events were reported.

Conclusion

Dalbavancin may be a safe and effective alternative for an early switch in treating severe gram-positive infections.

Trial registration

The trial was registered as NCT04847921 with clinicaltrials.gov.

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.

A Gap of Patients with Infective Endocarditis between Clinical Trials and the Real World

Introduction: A randomized control trial (RCT) is considered to be the highest level in the Evidence-Based Medicine (EBM) pyramid. While EBM is essential to make a practical tool such as a prognostic guideline, it has been unclear how many patients in the real world can be eligible for a randomized control trial (RCT). Patients and method: This study was performed to clarify if there is a difference in patients' profiles and clinical outcomes between the patients eligible and not eligible for any RCT. We reviewed all IE patients at our institute between 2007 and 2019. The patients were divided into two groups: those eligible for RCTs (RCT appropriate group) and those who were not (RCT inappropriate group). Exclusion criteria for clinical trials were set based on previous clinical trials. Results: A total of 66 patients were enrolled in the study. The median age was 70 years (range 18 to 87 years), and 46 (70%) were male. Seventeen (26%) of the patients were eligible for RCTs. Comparing the two groups, patients in the RCT appropriate group were younger and had fewer comorbidities. The disease severity was milder in the RCT appropriate groups than in the RCT inappropriate groups. Patients in the RCT appropriate group showed significantly longer overall survival times than those in the RCT inappropriate group (Log-Rank test, p < 0.001). Conclusions: We found a significant gap in patients' characteristics and clinical outcomes between the groups. Physicians should be aware that RCT can never reflect the real-world population.

Conventional Hospitalization versus Sequential Outpatient Parenteral Antibiotic Therapy for Staphylococcus aureus Bacteremia: Post-Hoc Analysis of a Multicenter Observational Cohort

It is not known whether sequential outpatient parenteral antimicrobial (OPAT) is as safe and effective as conventional hospitalization in patients with S. aureus bacteremia (SAB). A post-hoc analysis of the comparative effectiveness of conventional hospitalization versus sequential OPAT was performed in two prospective Spanish cohorts of patients with S. aureus bacteremia. The PROBAC cohort is a national, multicenter, prospective observational cohort of patients diagnosed in 22 Spanish hospitals between October 2016 and March 2017. The DOMUS OPAT cohort is a prospective observational cohort including patients from two university hospitals in Seville, Spain from 2012 to 2021. Multivariate regression was performed, including a propensity score (PS) for receiving OPAT, stratified analysis according to PS quartiles, and matched pair analyses based on PS. Four hundred and thirteen patients were included in the analysis: 150 in sequential OPAT and 263 in the full hospitalization therapy group. In multivariate analysis, including PS and center effect as covariates, 60-day treatment failure was lower in the OPAT group than in the full hospitalization group (p < 0.001; OR 0.275, 95%CI 0.129−0.584). In the PS-based matched analyses, sequential treatment under OPAT was not associated with higher 60-day treatment failure (p = 0.253; adjusted OR 0.660; % CI 0.324−1.345). OPAT is a safe and effective alternative to conventional in-patient therapy for completion of treatment in well-selected patients with SAB, mainly those associated with a low-risk source and without end-stage kidney disease.

Taking the route less traveled: on the way to COpAT

Antimicrobial therapy is an essential practice within medicine. Over the last 4 years, complex outpatient antimicrobial therapy (COpAT) with oral antimicrobials has become a rapidly developing area of practice and is non-inferior to outpatient parenteral antimicrobial therapy (OPAT) in certain infectious syndromes. Currently, the available literature does not describe the implementation of oral antimicrobials within the current outpatient antimicrobial therapy process. Throughout this article, the authors present a review of current literature, a proposed definition of COpAT and offer methods readers can utilize to implement an integrated COpAT/OPAT program with oral antimicrobial-specific monitoring within their current practice.

Outpatient Versus Inpatient Intravenous Antimicrobial Therapy: A Population-Based Observational Cohort Study of Adverse Events and Costs

BACKGROUND

Bacterial infections such as osteomyelitis and endocarditis routinely require several weeks of treatment with intravenous (IV) antimicrobials. Outpatient parenteral antimicrobial therapy (OPAT) programs allow patients to receive IV antimicrobials in an outpatient clinic or at home. The outcomes and costs of such treatments remain uncertain.

METHODS

We conducted a retrospective observational cohort study over a 5-year study interval (1 June 2012 to 31 March 2018) using population-based linked administrative data from British Columbia, Canada. Patients receiving OPAT following a hospitalization for bacterial infection were matched based on infection type and implied duration of IV antimicrobials to patients receiving inpatient parenteral antimicrobial therapy (IPAT). Cumulative adverse events and direct healthcare costs were estimated over a 90-day outcome interval.

RESULTS

In a matched cohort of 1842 patients, adverse events occurred in 35.6% of OPAT patients and 39.0% of IPAT patients (adjusted odds ratio, 1.04 [95% confidence interval {CI}, .83-1.30; P = .61). Relative to IPAT patients, OPAT patients were significantly more likely to experience hospital readmission (30.5% vs 23.0%) but significantly less likely to experience Clostridioides difficile diarrhea (1.2% vs 3.1%) or death (2.0% vs 8.8%). Estimated mean direct healthcare costs were $30 166 for OPAT patients and $50 038 for IPAT patients (cost ratio, 0.60; average cost savings with OPAT, $17 579 [95% CI, $14 131-$21 027]; P < .001).

CONCLUSIONS

Outpatient IV antimicrobial therapy is associated with a similar overall prevalence of adverse events and with substantial cost savings relative to patients remaining in hospital to complete IV antimicrobials. These findings should inform efforts to expand OPAT use.

Telling the difference and the telling differences between hospital in the home and outpatient parenteral antibiotic therapy

Doctors, authors, funders and hospital managers should take care to distinguish the important differences between hospital in the home (HIH) and outpatient parenteral antimicrobial therapy (OPAT) services. HIH is an inpatient service delivered at home usually by (or on behalf of) hospitals, which aims to substitute for a traditional inpatient stay. It does so by delivering a wide range of hospital treatments to patients at home, or residential aged care, using hospital medical and nursing staff, delivery technologies and venous access, pharmacy, radiology and pathology, and a structured system of on call and governance. OPAT is an outpatient service, usually run through infectious diseases physicians' offices or departments. Most care is delivered in infusion centres and requires patients to travel for their care. Generally, there is no after-hours support. HIH has supplanted the role of OPAT due to improved governance and a wider clinical and severity scope. HIH is accessible from hospital emergency departments or directly from residential aged care facilities. Inpatient capacity has been expanded during the COVID-19 pandemic. There is evidence that both HIH and OPAT can successfully treat their selected patient groups. There are no head-to-head studies, but in observational comparisons there might be more adverse drug events in OPAT. OPAT places a greater onus of care, supervision and travel needs on the patient and family. Where HIH is not available, OPAT may remain an alternative for some patients. However, HIH seeks to redefine the delivery of inpatient care away from the location of care.

How to investigate and manage a patient with a Staphylococcus aureus bacteraemia

Staphylococcus aureus bacteraemia is common, and associated with significant morbidity and mortality as a result of its high relapse rate and the risk of complicated infection. A positive blood culture for S. aureus should prompt a thorough patient assessment to identify a potential focus of infection, and the risk factors for the development or presence of complicated infection. Clinical management depends on the patient's characteristics and presenting features. This article gives a systematic approach to the patient with S. aureus bacteraemia, including points to look for on history and examination, the markers of complicated infection, and when to request transoesophageal echocardiography and further imaging. Treatment principles outlined include the rationale for choice of antibiotic treatment and need to involve infection specialists.

OPAT: proof of concept in a peripheral Belgian hospital after review of the literature

Since its introduction in the 1970s in the United States, outpatient parenteral antibiotic/antimicrobial therapy (OPAT) has been adopted internationally for long-term intravenous (IV) treatment of stable infectious diseases. The aim is to provide a safe and successful completion of IV antimicrobial treatment at the ambulatory care center or at home without complications and costs associated with hospitalization. OPAT implementation has been accelerated by progress in vascular access devices, newly available antibiotics, the emphasis on cost-savings, as well as an improved patient comfort and a reduced incidence of health care associated infections with a similar outcome. OPAT utilization is supported by an extensive published experience and guidelines of the British Society of Antimicrobial Chemotherapy and the Infectious Diseases Society of America for adults as well as for children. Despite these recommendations and its widespread adoption, in Belgium OPAT is only fully reimbursed and established for cystic fibrosis patients. Possible explanations for this unpopularity include physician unfamiliarity and a lack of uniform funding arrangements with higher costs for the patient. This article aims to briefly review benefits, risks, indications, financial impact for supporting OPAT in a non-university hospital as standard of care. Our experience with OPAT at the ambulatory care center of our hospital and its subsequent recent introduction in the home setting is discussed.

Outcomes According to Discharge Location for Persons Who Inject Drugs Receiving Outpatient Parenteral Antimicrobial Therapy

Background

Opioid use disorder poses a significant public health risk. Persons who inject drugs (PWID) suffer from high mortality and morbidity secondary to serious infectious diseases, often requiring prolonged courses of outpatient parenteral antibiotics. The goal of this study was to determine the outcomes of PWID discharged to home or to a skilled nursing or rehabilitation facility (SNF/rehab) with parenteral antibiotic treatment under an outpatient parenteral antimicrobial therapy (OPAT) program.

Methods

This is a retrospective observational study. The study population was identified via hospital and OPAT databases using substance use disorder diagnoses and confirmed through chart review. The study population included hospitalized PWID with injection drug use in the preceding 2 years who were discharged between 2010 and 2015 to complete at least 2 weeks of parenteral antibiotics and monitored by the OPAT program. Retrospective chart review was used to describe patient characteristics and outcomes.

Results

Fifty-two patients met inclusion criteria, 21 of whom were discharged to home and 31 were discharged to a SNF/rehab. Of the patients discharged to home, 17 (81%) completed their planned antibiotic courses without complication. Twenty (64%) patients discharged to a SNF/rehab completed the antibiotic courses without complication. Six (11%) patients had line infections, 6 (11%) had injection drug use relapse, and 12 (23%) required readmission.

Conclusions

Persons who inject drugs discharged home were not more likely to have complications than those discharged to a SNF/rehab. Home OPAT may be a safe discharge option in carefully selected patients.

Clinical and cost-effectiveness, safety and acceptability of community intravenous antibiotic service models: CIVAS systematic review

OBJECTIVE

Evaluate evidence of the efficacy, safety, acceptability and cost-effectiveness of outpatient parenteral antimicrobial therapy (OPAT) models.

DESIGN

A systematic review.

DATA SOURCES

MEDLINE, EMBASE, CINAHL, Cochrane Library, National Health Service (NHS) Economic Evaluation Database (EED), Research Papers in Economics (RePEc), Tufts Cost-Effectiveness Analysis (CEA) Registry, Health Business Elite, Health Information Management Consortium (HMIC), Web of Science Proceedings, International Pharmaceutical Abstracts, British Society for Antimicrobial Chemotherapy website. Searches were undertaken from 1993 to 2015.

STUDY SELECTION

All studies, except case reports, considering adult patients or practitioners involved in the delivery of OPAT were included. Studies combining outcomes for adults and children or non-intravenous (IV) and IV antibiotic groups were excluded, as were those focused on process of delivery or clinical effectiveness of 1 antibiotic over another. Titles/abstracts were screened by 1 reviewer (20% verified). 2 authors independently screened studies for inclusion.

RESULTS

128 studies involving >60 000 OPAT episodes were included. 22 studies (17%) did not indicate the OPAT model used; only 29 involved a comparator (23%). There was little difference in duration of OPAT treatment compared with inpatient therapy, and overall OPAT appeared to produce superior cure/improvement rates. However, when models were considered individually, outpatient delivery appeared to be less effective, and self-administration and specialist nurse delivery more effective. Drug side effects, deaths and hospital readmissions were similar to those for inpatient treatment, but there were more line-related complications. Patient satisfaction was high, with advantages seen in being able to resume daily activities and having greater freedom and control. However, most professionals perceived challenges in providing OPAT.

CONCLUSIONS

There were no systematic differences related to the impact of OPAT on treatment duration or adverse events. However, evidence of its clinical benefit compared with traditional inpatient treatment is lacking, primarily due to the dearth of good quality comparative studies. There was high patient satisfaction with OPAT use but the few studies considering practitioner acceptability highlighted organisational and logistic barriers to its delivery.

The Community IntraVenous Antibiotic Study (CIVAS): a mixed-methods evaluation of patient preferences for and cost-effectiveness of different service models for delivering outpatient parenteral antimicrobial therapy

Background

Outpatient parenteral antimicrobial therapy (OPAT) is widely used in most developed countries, providing considerable opportunities for improved cost savings. However, it is implemented only partially in the UK, using a variety of service models.

Objectives

The aims of this research were to (1) establish the extent of OPAT service models in England and identify their development; (2) evaluate patients’ preferences for different OPAT service delivery models; (3) assess the cost-effectiveness of different OPAT service delivery models; and (4) convene a consensus panel to consider our evidence and make recommendations.

Methods

This mixed-methods study included seven centres providing OPAT using four main service models: (1) hospital outpatient (HO) attendance; (2) specialist nurse (SN) visiting at home; (3) general nurse (GN) visiting at home; and (4) self-administration (SA) or carer administration. Health-care providers were surveyed and interviewed to explore the implementation of OPAT services in England. OPAT patients were interviewed to determine key service attributes to develop a discrete choice experiment (DCE). This was used to perform a quantitative analysis of their preferences and attitudes. Anonymised OPAT case data were used to model cost-effectiveness with both Markov and simulation modelling methods. An expert panel reviewed the evidence and made recommendations for future service provision and further research.

Results

The systematic review revealed limited robust literature but suggested that HO is least effective and SN is most effective. Qualitative study participants felt that different models of care were suited to different types of patient and they also identified key service attributes. The DCE indicated that type of service was the most important factor, with SN being strongly preferred to HO and SA. Preferences were influenced by attitudes to health care. The results from both Markov and simulation models suggest that a SN model is the optimal service for short treatment courses (up to 7 days). Net monetary benefit (NMB) values for HO, GN and SN services were £2493, £2547 and £2655, respectively. For longer treatment, SA appears to be optimal, although SNs provide slightly higher benefits at increased cost. NMB values for HO, GN, SN and SA services were £8240, £9550, £10,388 and £10,644, respectively. The simulation model provided useful information for planning OPAT services. The expert panel requested more guidance for service providers and commissioners. Overall, they agreed that mixed service models were preferable.

Limitations

Recruitment to the qualitative study was suboptimal in the very elderly and ethnic minorities, so the preferences of patients from these groups might not be represented. The study recruited from Yorkshire, so the findings may not be applicable nationally.

Conclusions

The quantitative preference analysis and economic modelling favoured a SN model, although there are differences between sociodemographic groups. SA provides cost savings for long-term treatment but is not appropriate for all.

Future work

Further research is necessary to replicate our results in other regions and populations and to evaluate mixed service models. The simulation modelling and DCE methods used here may be applicable in other health-care settings.

Funding

The National Institute for Health Research Health Service and Delivery Research programme.

Safety and efficacy of daptomycin in outpatient parenteral antimicrobial therapy: a prospective and multicenter cohort study (DAPTODOM trial)

BACKGROUND

Daptomycin is an optimal choice for outpatient parenteral antibiotic therapy (OPAT) because of its safety, once-daily administration and its activity against Gram-positive bacteria. Although daptomycin is increasingly being used in OPAT, limited information about its safety in this scenario is available.

METHODS

We performed a prospective multicentre pilot study to evaluate the safety of daptomycin in outpatients with proved or suspected Gram-positive infections (DAPTODOM). The primary objective was to evaluate the safety and the secondary objective to evaluate the efficacy in OPAT. We also looked at the development of daptomycin resistance in those cases with microbiological failure.

RESULTS

We included 54 patients from 12 Spanish hospitals, 67% male with a mean age of 67.1 years. Most patients (87%) had chronic underlying diseases. The main reason for inclusion was skin and soft-tissue infections in 52%, followed by bacteremia or endocarditis in 34%. Staphylococcus aureus accounted for 44% of the isolates (24% were methicillin-resistant), coagulase-negative staphylococci 15% and enterococci 7%. Two patients (4%) had to be readmitted because of complications; only one patient had an adverse effect related to daptomycin (increase in serum creatine kinase levels), which disappeared after discontinuation (2%). At the end of follow-up, 96% of patients had good outcome and only 4% of patients did not have a clinical or microbiological cure. The use of a 2-minute bolus in 18 cases was not associated with adverse effects.

CONCLUSIONS

Daptomycin was safe and efficacious in outpatients with Gram-positive bacterial infections and can be administered in 2-minute bolus infusion.

Patient Characteristics and Outcomes of Outpatient Parenteral Antimicrobial Therapy: A Retrospective Study

Outpatient parenteral antimicrobial therapy (OPAT) is a safe and effective alternative to hospitalization for many patients with infectious diseases. The objective of this study was to describe the OPAT experience at a Canadian tertiary academic centre in the absence of a formal OPAT program. This was achieved through a retrospective chart review of OPAT patients discharged from Sunnybrook Health Sciences Centre within a one-year period. Between June 2012 and May 2013, 104 patients (median age 63 years) were discharged home with parenteral antimicrobials. The most commonly treated syndromes included surgical site infections (33%), osteoarticular infections (28%), and bacteremia (21%). The most frequently prescribed antimicrobials were ceftriaxone (21%) and cefazolin (20%). Only 56% of the patients received follow-up care from an infectious diseases specialist. In the 60 days following discharge, 43% of the patients returned to the emergency department, while 26% required readmission. Forty-eight percent of the return visits were due to infection relapse or treatment failure, and 23% could be attributed to OPAT-related complications. These results suggest that many OPAT patients have unplanned health care encounters because of issues related to their infection or treatment, and the creation of a formal OPAT clinic may help improve outcomes.

Community IntraVenous Antibiotic Study (CIVAS): protocol for an evaluation of patient preferences for and cost-effectiveness of community intravenous antibiotic services

INTRODUCTION

Outpatient parenteral antimicrobial therapy (OPAT) is used to treat a wide range of infections, and is common practice in countries such as the USA and Australia. In the UK, national guidelines (standards of care) for OPAT services have been developed to act as a benchmark for clinical monitoring and quality. However, the availability of OPAT services in the UK is still patchy and until quite recently was available only in specialist centres. Over time, National Health Service (NHS) Trusts have developed OPAT services in response to local needs, which has resulted in different service configurations and models of care. However, there has been no robust examination comparing the cost-effectiveness of each service type, or any systematic examination of patient preferences for services on which to base any business case decision.

METHODS AND ANALYSIS

The study will use a mixed methods approach, to evaluate patient preferences for and the cost-effectiveness of OPAT service models. The study includes seven NHS Trusts located in four counties. There are five inter-related work packages: a systematic review of the published research on the safety, efficacy and cost-effectiveness of intravenous antibiotic delivery services; a qualitative study to explore existing OPAT services and perceived barriers to future development; an economic model to estimate the comparative value of four different community intravenous antibiotic services; a discrete choice experiment to assess patient preferences for services, and an expert panel to agree which service models may constitute the optimal service model(s) of community intravenous antibiotics delivery.

ETHICS AND DISSEMINATION

The study has been approved by the NRES Committee, South West-Frenchay using the Proportionate Review Service (ref 13/SW/0060). The results of the study will be disseminated at national and international conferences, and in international journals.

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.

Single-dose oritavancin in the treatment of acute bacterial skin infections

BACKGROUND

Oritavancin is a lipoglycopeptide with bactericidal activity against gram-positive bacteria. Its concentration-dependent activity and prolonged half-life allow for single-dose treatment.

METHODS

We conducted a randomized, double-blind trial in which adults with acute bacterial skin and skin-structure infections received either a single intravenous dose of 1200 mg of oritavancin or a regimen of intravenous vancomycin twice daily for 7 to 10 days. Three efficacy end points were tested for noninferiority. The primary composite end point was defined as cessation of spreading or reduction in lesion size, absence of fever, and no need for administration of a rescue antibiotic 48 to 72 hours after administration of oritavancin. Secondary end points were clinical cure 7 to 14 days after the end of treatment, as determined by a study investigator, and a reduction in lesion size of 20% or more 48 to 72 hours after administration of oritavancin.

RESULTS

The modified intention-to-treat population comprised 475 patients who received oritavancin and 479 patients who received vancomycin. All three efficacy end points met the prespecified noninferiority margin of 10 percentage points for oritavancin versus vancomycin: primary end point, 82.3% versus 78.9% (95% confidence interval [CI] for the difference, -1.6 to 8.4 percentage points); investigator-assessed clinical cure, 79.6% versus 80.0% (95% CI for the difference, -5.5 to 4.7 percentage points); and proportion of patients with a reduction in lesion area of 20% or more, 86.9% versus 82.9% (95% CI for the difference, -0.5 to 8.6 percentage points). Efficacy outcomes measured according to type of pathogen, including methicillin-resistant Staphylococcus aureus, were similar in the two treatment groups. The overall frequency of adverse events was also similar, although nausea was more common among those treated with oritavancin.

CONCLUSIONS

A single dose of oritavancin was noninferior to twice-daily vancomycin administered for 7 to 10 days for the treatment of acute bacterial skin and skin-structure infections caused by gram-positive pathogens. (Funded by the Medicines Company; SOLO I ClinicalTrials.gov number, NCT01252719.).

Daptomycin versus vancomycin for osteoarticular infections due to methicillin-resistant Staphylococcus aureus (MRSA): a nested case-control study

Vancomycin is the standard antibiotic for the treatment of methicillin-resistant Staphylococcus aureus (MRSA) infections. While daptomycin is approved for MRSA bacteremia, its effectiveness in osteoarticular infections (OAIs) has not been established. A 1:2 nested case-control study of adult patients with MRSA OAIs admitted to an academic center from 2005 to 2010 was carried out. Clinical outcomes and drug toxicity in patients treated with daptomycin versus vancomycin were compared. Twenty patients with MRSA OAIs treated with daptomycin were matched to 40 patients treated with vancomycin. The median age of the patients was 52 years (range, 25-90), and 40 (67%) were male. Most patients had osteomyelitis (82%), predominantly from a contiguous source (87%). Forty percent were diabetics. Diabetic patients were more likely to receive vancomycin than daptomycin [20 (50%) vs. 4 (20%); p = 0.03]. Vancomycin was more often combined with antibiotics other than daptomycin [22 (55%) vs. 5 (25%); p = 0.03]. The median total antibiotic treatment duration was 48 (daptomycin) vs. 46 days (vancomycin) (p = 0.5). Ninety percent of daptomycin-treated patients had previously received vancomycin for a median of 14.5 days (range, 2-36). Clinical success rates were similar between daptomycin and vancomycin at 3 months [15 (75%) vs. 27 (68%); p = 0.8] and 6 months [14 (70%) vs. 23 (58%); p = 0.5], even after propensity score-based adjustment for antibiotic assignment. The frequency of adverse events was similar between treatment groups [1 (5%) vs. 7 (18%); p = 0.2]. Daptomycin and vancomycin achieved similar rates of clinical success and drug tolerability. Daptomycin is a reasonable alternative for treating MRSA OAIs, particularly in patients where therapy with vancomycin has not been well tolerated.

Outpatient parenteral antimicrobial therapy for surgery patients: A comparison with previous standard of care

BACKGROUND

Current literature reports that outpatient parenteral antimicrobial therapy (OPAT) programs improve cure rates, and reduce length of hospitalization and costs. OPAT programs are still relatively new in Canada.

OBJECTIVE

To evaluate the benefits of an OPAT program initiated at a multispecialty tertiary care facility in Toronto, Ontario, compared with the previous standard of care.

METHODS

The present retrospective observational study was conducted using data from a group of surgical patients who were treated for active infections. Between February 1, 2010 and November 30, 2010, a total of 108 surgical patients were enrolled in the OPAT program. Patients were matched 1:1 with historical controls discharged between January 1, 2001 and January 1, 2010 according to age, sex, type of surgery, infection and comorbidities (Charlson Comorbidity Index). Cure rate, 30-day rehospitalization and length of stay were evaluated as primary end points.

RESULTS

Of 108 eligible OPAT patients, 21 were matched to the control group using the prespecified criteria. For this cohort, the OPAT program was associated with improved cure rates (OPAT 61.7% versus control 57.1%; P>0.10), reduction in rehospitalization rate (14.3% versus 28.6%; P>0.10) and reduced length of stay (10.7 versus 13.9 days, P>0.10) compared with the control group.

CONCLUSIONS

For this cohort of surgery patients, the OPAT program demonstrated a trend toward improved outcomes but did not achieve statistical significance. Due to the lack of statistical power, further evaluation is required to determine the full benefit of OPAT to patients and the health care system.

Outpatient parenteral antibiotic therapy: principles and practice

Outpatient parenteral antimicrobial therapy (OPAT) refers to the administration of a parenteral antimicrobial in a non inpatient or ambulatory setting with the explicit aim of facilitating admission avoidance or early discharge. Whilst OPAT has predominantly been the domain of the infection specialist, the internal medicine specialist has a key role in service development and delivery as a component of broader ambulatory care initiatives such as "hospital at home". Main drivers for OPAT are patient welfare, reduction of risk of health care associated infection and cost-effective use of hospital resources. The safe practice of OPAT is dependent on a team approach with careful patient selection and antimicrobial management with programmed and adaptable clinical monitoring and assessment of outcome. Gram-positive infections, including cellulitis, bone and joint infection, bacteraemia and endocarditis are key infections potentially amenable to OPAT whilst resistant Gram-negative infections are of increasing importance. Ceftriaxone, teicoplanin, daptomycin and ertapenem lend themselves well to OPAT due to daily (or less frequent) bolus administration, although any antimicrobial may be administered if the patient is trained to administer and/or an appropriate infusion device is employed. Clinical experience from NHS Greater Glasgow and Clyde is presented to illustrate the key principles of OPAT as practised in the UK. Increasingly complex patients with multiple medical needs, the relative scarcity of inpatient resources and the broader challenge of ambulatory care and "hospital at home" will ensure the internal medicine specialist will have a key role in the future development of OPAT.

Risk factors for failure of outpatient parenteral antibiotic therapy (OPAT) in infective endocarditis

Objectives

To identify risk factors for failure of outpatient antibiotic therapy (OPAT) in infective endocarditis (IE).

Patients and methods

We identified IE cases managed at a single centre over 12 years from a prospectively maintained database. ‘OPAT failure’ was defined as unplanned readmission or antibiotic switch due to adverse drug reaction or antibiotic resistance. We analysed patient and disease-related risk factors for OPAT failure by univariate and multivariate logistic regression. We also retrospectively collected follow-up data on adverse disease outcome (defined as IE-related death or relapse) and performed Kaplan–Meier survival analysis up to 36 months following OPAT.

Results

We identified 80 episodes of OPAT in IE. Failure occurred in 25/80 episodes (31.3%). On multivariate analysis, cardiac or renal failure [pooled OR 7.39 (95% CI 1.84–29.66), P = 0.005] and teicoplanin therapy [OR 8.69 (95% CI 2.01–37.47), P = 0.004] were independently associated with increased OPAT failure. OPAT failure with teicoplanin occurred despite therapeutic plasma levels. OPAT failure predicted adverse disease outcome up to 36 months (P = 0.016 log-rank test).

Conclusions

These data caution against selecting patients with endocarditis for OPAT in the presence of cardiac or renal failure and suggest teicoplanin therapy may be associated with suboptimal OPAT outcomes. Alternative regimens to teicoplanin in the OPAT setting should be further investigated.

[Safety and efficacy of daptomycin therapy in older adults with pluripathology]

Serious Gram-positive bacterial infections are a major cause of morbidity and mortality among older adults and can pose a significant challenge to clinicians. Although more than 50% of patients treated with daptomycin are > 65 years old, there are few data evaluating the efficacy and safety of daptomcyn in this population. Analysis of data from patients > 65 years old included in the Cubicin Outcomes Registry and Experience (CORE), a multicenter, retrospective registry designed to collect post-marketing clinical data on patients who received daptomycin, and in its European version, the EUCORE, showed similar rates of efficacy and safety in this population to those in younger patients, suggesting that daptomycin is also a valuable option in older patients with serious Gram-positive infections.

Outpatient parenteral antimicrobial therapy with ceftriaxone, a review

BACKGROUND

More than 30 years since it was developed for clinical use, the third-generation cephalosporin ceftriaxone remains the most commonly used agent for outpatient parental antimicrobial therapy (OPAT). Recent antimicrobial stewardship programmes have tended to restrict ceftriaxone use in hospitals to control antibiotic resistance and outbreaks of Clostridium difficle infection (CDI). Considering the expansion of OPAT programmes both in the UK and worldwide, revisiting the role of ceftriaxone in OPAT in the context of changing antimicrobial prescribing practices is timely.

AIM OF THE REVIEW

To identify the evidence base for OPAT, review current and historical data on indications for, and safety of ceftriaxone within the OPAT setting, and to provide some perspectives on the future role of ceftriaxone.

METHOD

We searched PubMed and Scopus for articles published in English, and hand searched reference lists. We also conducted a complementary descriptive analysis of prospectively acquired data on the use of ceftriaxone in more than 1,300 OPAT episodes over a 10-year period in our UK centre.

RESULTS

Ceftriaxone has an excellent safety profile in the OPAT setting, and its broad spectrum of activity makes it an established agent in a wide range of clinical infection syndromes, such as skin and soft-tissue infection, bone and joint infection, streptococcal endocarditis and several others. Intriguingly, in contrast to the inpatient setting, liberal use of ceftriaxone in OPAT has not been strongly linked to CDI, suggesting additional patient and environmental factors may be important in mediating CDI risk.

Native valve endocarditis caused by coagulase negative staphylococci; an appeal to start outpatient antimicrobial therapy: an unusual case report

Coagulase negative staphylococci (CNS) were a rare cause of native valve endocarditis. However, they are emerging as an important cause of native valve endocarditis (NVE) in both community and healthcare settings. We describe a 64 yrs. old male who developed mitral valve endocarditis caused by coagulase negative staphylococci. There were no predisposing conditions or underlying cardiac disease that could have been the risk factor for the development of native valve infection. The patient had good recovery after six weeks of treatment with anti-staphylococcal antibiotics.

Impact of a Multidisciplinary Team Review of Potential Outpatient Parenteral Antimicrobial Therapy Prior to Discharge from an Academic Medical Center

Background::

Outpatient parenteral antimicrobial therapy (OPAT) is frequently prescribed at hospital discharge, often without infectious diseases (ID) clinician oversight. We developed a multidisciplinary team, including an ID pharmacist, to review OPAT care plans at hospital discharge to improve safety, clinical efficacy, practicality, and appropriateness of the proposed antimicrobial regimen.

Objective:

To evaluate the impact of the OPAT team on regimen safety, efficacy, and complexity; calculate the economic benefits of the service by avoiding hospital discharge delay, central venous catheter placement, or need for OPAT; and evaluate the discharge environment among OPAT referrals.

Methods:

In an observational design, we analyzed the impact of an OPAT team from July 2009 through June 2010 at a large academic tertiary care hospital. All patients with plans for continued parenteral therapy after discharge referred to the OPAT team were included in the analysis. Patients were excluded if OPAT was cancelled prior to processing of the referral.

Results:

During the 1-year study period. 569 of 644 consecutive referrals to the OPAT team met inclusion criteria, resulting in 494 OPAT courses. Interventions by an ID pharmacist were made for safety (56%), regimen complexity (41%), and efficacy (29%). Lack of formal ID physician consultation resulted in more interventions for safety (64% vs 48%, p < 0.001) and efficacy (36% vs 21%, p < 0.001). Discharge delays were avoided for 35 referrals, resulting in 228 hospital days avoided and approximately $366,000 in hospital bed cost savings. Use of OPAT was avoided in 75 referrals (13.2%), preventing central venous catheter placement in 48 patients (8.4%), resulting in an additional $58,080 in cost savings.

Conclusions:

The OPAT team optimized safety, efficacy, and convenience of OPAT while providing substantial cost savings. Further studies are needed to confirm the program's cost-effectiveness.

Optimizing delivery of care for patients with MRSA infection: focus on transitions of care

Staphylococcus aureus is among the most prevalent pathogens isolated from hospitalized patients; those infected with methicillin-resistant strains have longer hospital stays and higher total costs compared with those infected by methicillin-susceptible strains. A multidisciplinary team of health care providers, including hospitalists and other hospital-based physicians, clinical pharmacists, infectious disease specialists, infection control professionals, and case managers, is key to improving treatment and outcomes in these patients. Optimizing transitions of care for hospitalized patients with S aureus infections can improve quality and reduce total costs of care. Hospital length of stay can be shortened by initiating timely, appropriate empiric therapy and by transitioning suitable patients to outpatient antimicrobial therapy. The number of hospitalizations can be reduced by identifying patients who are suitable candidates for initial outpatient antimicrobial therapy. Consistent with good antimicrobial stewardship, the risk of resistance can be minimized by de-escalating empiric therapy to a more narrow-spectrum agent once culture and susceptibility testing results are known. There are several antimicrobial agents available for the management of S aureus infections, including methicillin-resistant S aureus. Consideration of these agents' characteristics may facilitate optimal transition of patients through health care settings.

Maximizing positive outcomes for patients with staphylococcal infections

Maximizing positive outcomes for serious Gram-positive infections, such as those caused by Staphylococcus species, requires an aggressive treatment approach. Although specific approaches will depend upon many factors, the underlying common strategy should recognize the positive contribution of minimizing complications and inpatient treatment duration and the efficient use of healthcare resources, while also focusing on rapid resolution of infection and safety and tolerability. To advance the standard of care for patients, we need to utilize therapies that enable such a range of factors to be improved. Treatment guidelines are useful to establish evidence-based standards of care, but they are updated infrequently and there is currently no pan-European consensus for the treatment of staphylococcal infections. With the benefit of the clinical experience that has been acquired for the most recently licensed antibiotics, together with an appreciation of the appropriate usage of older agents, there are good prospects for achieving positive outcomes earlier and in a greater range of patients with staphylococcal infections, and treatment guidelines should be updated regularly to reflect this.