Comparison of Oral and Intravenous Definitive Antibiotic Therapy for Beta-Hemolytic Streptococcus Species Bloodstream Infections from Soft Tissue Sources: a Propensity Score-Matched Analysis

Oral switch vs. continued intravenous antibiotic therapy in patients with bacteraemia and sepsis: a systematic review and meta-analysis

BACKGROUND

Bacteraemia and sepsis have traditionally required continued intravenous (IV) antibiotics.

OBJECTIVES

This study aims to evaluate if early transition to oral antibiotics is non-inferior to continued IV antibiotic therapy in treating patients with bacteraemia and sepsis.

DATA SOURCES

Data sources include MEDLINE, Embase, Web of Science, the Cochrane Library, and Wanfang databases from inception to 13 July 2024, along with clinical trial registries and Google.com.

STUDY ELIGIBILITY CRITERIA

Study eligibility criteria include randomized controlled trials (RCTs) and cohort studies.

PARTICIPANTS

Participants include patients with bacteraemia and sepsis.

INTERVENTIONS

Interventions include early transition to oral antibiotics vs. continued IV antibiotics. Early oral switch was defined as 5-9 days for uncomplicated Staphylococcus aureus bacteraemia, <4 weeks for complicated S. aureus bacteraemia, 3-7 days for uncomplicated Streptococcus bacteraemia, and 3-5 days for uncomplicated Enterobacterales bacteraemia.

ASSESSMENT OF RISK OF BIAS

Assessment of risk of bias includes Cochrane risk of bias tool and Newcastle-Ottawa Scale.

METHODS OF DATA SYNTHESIS

Random-effect models were used to pool the data. The primary outcome was treatment failure. The non-inferiority margin for treatment failure was 10%. The Grading of Recommendations Assessment, Development, and Evaluation approach was used to rate the certainty of the evidence.

RESULTS

In total, 38 studies (6 RCTs, 10 adjusted cohorts, and 22 unadjusted cohorts) involving 11 566 patients were included. A primary analysis of 6 RCTs and 10 adjusted cohorts comprised 7102 patients. High-certainty evidence from six RCTs showed that early transition to oral antibiotics was non-inferior to continued IV therapy for treatment failure (n = 529; OR 0.89; 95% CI: 0.54-1.48). Low-certainty evidence from five adjusted cohorts also found no significant difference in treatment failure between the two groups (n = 929; OR 0.60; 95% CI: 0.29-1.72). Moderate-certainty evidence showed that oral switch therapy significantly reduced hospital stay (n = 2041; mean difference: -5.19 days; 95% CI: -8.16 to -2.22).

CONCLUSIONS

Early transition to oral antibiotics was non-inferior to continued IV antibiotic treatment for bacteraemia and sepsis.

Treatment of Complicated Gram-Positive Bacteremia and Infective Endocarditis

The Gram-positive cocci Staphylococcus aureus, Streptococcus spp., and Enterococcus spp. are the most frequent causative organisms of bloodstream infections and infective endocarditis. "Complicated bacteremia" is a term used in S. aureus bloodstream infections and originally implied the presence of metastatic infectious foci (i.e. complications of S. aureus bacteremia). These complications demand longer antimicrobial treatment durations and, frequently, interventional source control. Several risk factors for the incidence of bacteremia complications have been identified and are often used for the definition of complicated bacteremia. Here, we discuss management and diagnostic approaches and treatment options for patients with complicated bacteremia, with particular focus on infective endocarditis. We also summarize the available evidence regarding imaging modalities and the choice of antimicrobial mono- or combination therapy according to resistance patterns for these pathogens as well as treatment durations and optimized application routes. Finally, we synopsize current and future areas of research in complicated bacteremia and infective endocarditis.

Duration of antimicrobial treatment for uncomplicated streptococcal bacteraemia: Another example of shorter is better

OBJECTIVES

Duration of treatment for uncomplicated streptococcal bacteraemia is unknown. The study aims to assess clinical outcomes of patients with uncomplicated streptococcal bacteraemia receiving a short course (5-10 days) of antimicrobial treatment compared to those receiving the traditional, longer duration (11-18 days).

METHODS

This retrospective study was conducted at the Lausanne University Hospital, Switzerland and included episodes of uncomplicated streptococcal bacteraemia among adult patients from 2015 to 2023. Clinical failure was defined as mortality, recurrence of bacteraemia by the same streptococcal species and development in bone and joint infection within 120 days.

RESULTS

During the study period, 336 episodes of uncomplicated streptococcal bacteraemia were included. The median duration of antimicrobial treatment was 10 days (interquartile range: 7-14); 184 (55%) and 152 (45%) episodes received a short (5-10 days) and long (11-18 days) duration of antimicrobial treatment, respectively. Forty-three (13%) episodes had clinical failure; 120-day mortality was 11% (36 episodes); recurrence of bacteraemia by the same streptococcal species was observed in 8 episodes (2%). No difference in clinical failure was observed between episodes receiving short and long courses of antimicrobial treatment (10% versus 16%; P 0.143). The Cox multivariable regression model found that a Charlson comorbidity index >4 (aHR 4.87, 95% CI 3.08-7.71), and septic shock (1.67, 1.04-2.67) were associated with clinical failure; a short course of antimicrobial treatment was not associated with clinical failure (0.90, 0.57-1.12).

CONCLUSIONS

This study has shown that a short duration of antimicrobial treatment for cases of streptococcal bacteraemia is effective and safe.

Continued Intravenous Versus First Week Transition to Oral Antibiotic Therapy in Bloodstream Infections: A Systematic Review and Meta-Analysis

Bloodstream infections (BSIs) are a major public health concern worldwide, requiring prompt and effective antibiotic therapy. Traditionally, intravenous (IV) antibiotics have been preferred for their rapid action and consistent absorption. However, interest is growing in transitioning to oral (PO) antibiotics when suitable, due to similar pharmacokinetics, improved patient outcomes, and reduced healthcare costs. This meta-analysis aims to evaluate the clinical effectiveness of switching from IV to PO antibiotics for both gram-negative and gram-positive BSIs. Scopus, Embase, and PubMed databases were comprehensively searched until March 2023. The review included randomized controlled trials and cohort studies comparing continued IV therapy with early transition from IV to PO antibiotics within the first week of admission. Inclusion criteria encompassed studies involving adult patients (≥18 years) and reporting specific outcomes such as treatment success, mortality, and hospital readmissions. Meta-analysis of 17 studies comprising 11,245 patients demonstrated higher treatment success rates overall (OR: 1.40, P=0.04), particularly in gram-negative infections (OR: 1.42, P=0.05). However, this effect was not statistically significant in the gram-positive subgroup (OR: 1.41, P=0.036). Oral switch significantly reduced all-cause mortality overall (OR: 0.35, P=0.003), especially in gram-negative infections (OR: 0.22, P=0.008), but not significantly in gram-positive infections (OR: 0.60, P=0.09). Both gram-negative and gram-positive infections benefited from shorter hospital stays (P<0.0001), despite significant heterogeneity. Hospital readmission rates did not significantly differ between IV and oral switch groups (P=0.53). Our meta-analysis suggests potential benefits of early transition from IV to PO antibiotics for BSIs, including improved treatment outcomes and shorter hospital stays without an increased risk of readmission. However, these findings are subject to selection bias, and further standardized randomized trials are essential to validate these results.

Oral Antibiotics for Bacteremia and Infective Endocarditis: Current Evidence and Future Perspectives

Bacteremia and endocarditis are two clinical syndromes that, for decades, were managed exclusively with parenteral antimicrobials, irrespective of a given patient's clinical condition, causative pathogen, or its antibiotic susceptibility profile. This clinical approach, however, was based on low-quality data and outdated expert opinions. When a patient's condition has improved, gastrointestinal absorption is not compromised, and an oral antibiotic regimen reaching adequate serum concentrations is available, a switch to oral antibacterials can be applied. Although available evidence has reduced the timing of the oral switch in bacteremia to three days/until clinical improvement, there are only scarce data regarding less than 10-day intravenous antibiotic therapy in endocarditis. Many standard or studied oral antimicrobial dosages are smaller than the approved doses for parenteral administration, which is a risk factor for treatment failure; in addition, the gastrointestinal barrier may affect drug bioavailability, especially when the causative pathogen has a minimum inhibitory concentration that is close to the susceptibility breakpoint. A considerable number of patients infected by such near-breakpoint strains may not be potential candidates for oral step-down therapy to non-highly bioavailable antibiotics like beta-lactams; different breakpoints should be determined for this setting. This review will focus on summarizing findings about pathogen-specific tailoring of oral step-down therapy for bacteremia and endocarditis, but will also present laboratory and clinical data about antibiotics such as beta-lactams, linezolid, and fosfomycin that should be studied more in order to elucidate their role and optimal dosage in this context.

Intravenous versus Partial Oral Antibiotic Therapy in the Treatment of Uncomplicated Bloodstream Infection Due to Streptococcus Species

This retrospective cohort study examines effectiveness of partial oral antibiotic regimens in uncomplicated bloodstream infections (BSIs) due to Streptococcus species compared to standard intravenous therapy. Adult patients with uncomplicated streptococcal BSIs from April 2016 to June 2020 in seven hospitals in South Carolina, USA, were evaluated. Multivariate Cox proportional hazards regression was used to examine the time to treatment failure within 90 days of a BSI after adjustment for the propensity to receive partial oral therapy. Multivariate linear regression was used to examine the hospital length of stay (HLOS). Among the 222 patients included, 99 received standard intravenous antibiotics and 123 received partial oral therapy. Of the standard intravenous therapy group, 46/99 (46.5%) required outpatient parenteral antibiotic therapy (OPAT). There was no difference in the risk of treatment failure between partial oral and standard intravenous therapy (hazards ratio 0.53, 95% CI 0.18, 1.60; p = 0.25). Partial oral therapy was independently associated with a shorter HLOS after adjustments for the propensity to receive partial oral therapy and other potential confounders (-2.23 days, 95% CI -3.53, -0.94; p < 0.001). Transitioning patients to oral antibiotics may be a reasonable strategy in the management of uncomplicated streptococcal BSIs. Partial oral therapy does not seem to have a higher risk of treatment failure and may spare patients from prolonged hospitalizations and OPAT complications.