Uncomplicated Staphylococcus aureus Bacteremia Treatment Duration and Outcomes at an Academic Medical Center

Long versus short course anti-microbial therapy of uncomplicated Staphylococcus aureus bacteraemia: a systematic review

BACKGROUND

Current guidelines recommend at least 2 weeks duration of antibiotic therapy (DOT) for patients with uncomplicated Staphylococcus aureus bacteraemia (SAB) but the evidence for this recommendation is unclear.

OBJECTIVES

To perform a systematic literature review assessing current evidence for recommended DOT for patients with SAB.

METHODS

The following are the methods used for this study.

DATA SOURCES

We searched MEDLINE, ISI Web of Science, the Cochrane Database and clinicaltrials.gov from inception to March 30, 2024. References of eligible studies were screened and experts in the field contacted for additional articles.

STUDY ELIGIBILITY CRITERIA

All clinical studies, regardless of design, publication status and language.

PARTICIPANTS

Adult patients with uncomplicated SAB.

INTERVENTIONS

Long (>14 days; >18 days; 11-16 days) vs. short (≤14 days; 10-18 days; 6-10 days, respectively) DOT with the DOT being defined as the first until the last day of antibiotic therapy.

ASSESSMENT OF RISK OF BIAS

Risk of bias was assessed using the ROBINS-I-tool.

METHODS OF DATA SYNTHESIS

The primary outcome was 90-day all-cause mortality. Only studies presenting results of adjusted analyses for mortality were included. Data synthesis could not be performed.

RESULTS

Eleven nonrandomized studies were identified that fulfilled the pre-defined inclusion criteria, of which three studies reported adjusted effect ratios. Only these were included in the final analysis. We did not find any RCT. Two studies with 1230 patients reported the primary endpoint 90-day all-cause mortality. Neither found a statistically significant superiority for longer (>14 days; 11-16 days) or shorter DOT (≤14 days; 6-10 days, respectively) for patients with uncomplicated SAB. Two studies investigated the secondary endpoint 30-day all-cause mortality (>18 days; 11-16 days vs. 10-18 days; 6-10 days, respectively) and did not find a statistically significant difference. All included studies had a moderate risk of bias.

CONCLUSIONS

Sound evidence that supports any duration of antibiotic treatment for patients with uncomplicated SAB is lacking.

Short-term versus usual-term antibiotic treatment for uncomplicated Staphylococcus aureus bacteremia: a systematic review and meta-analysis

Introduction

Uncomplicated Staphylococcus aureus bacteremia remains a leading cause of morbidity and mortality in hospitalized patients. Current guidelines recommend a minimum of 14 days of treatment.

Objective

To evaluate the efficacy and safety of short versus usual antibiotic therapy in adults with uncomplicated S. aureus bacteremia (SAB).

Methods

We developed a search strategy to identify systematic review and meta-analysis of non-randomized studies (NRS), comparing short versus usual or long antibiotic regimens for uncomplicated SAB in MEDLINE, Embase, and the Cochrane Register up to June 2023. The risk of bias was assessed using the ROBINS I tool. The meta-analysis was performed using Review Manager software with a random effect model.

Results

Six NRS with a total of 1700 patients were included. No significant differences were found when comparing short versus prolonged antibiotic therapy as defined by the authors for 90-day mortality [odds ratio (OR): 1.09; 95% confidence interval (CI): 0.82-1.46, p: 0.55; I2 = 0%] or 90-day recurrence or relapse of bacteremia [OR: 0.72; 95% CI: 0.31-1.68, p: 0.45; I2 = 26%]. Sensitivity analysis showed similar results when comparing a predefined duration of <14 days versus ⩾14 days and when excluding the only study with a high risk of bias.

Conclusion

Shorter-duration regimens could be considered as an alternative option for uncomplicated SAB in low-risk cases. However, based on a small number of studies with significant methodological limitations and risk of bias, the benefits and harms of shorter regimens should be analyzed with caution. Randomized clinical trials are needed to determine the best approach regarding the optimal duration of therapy.

Haemodialysis vascular catheter-related blood stream infection: Organism types and clinical outcomes

Catheter-related bloodstream infection (CRBI) is an important complication of catheter use for haemodialysis, but it remains unclear whether clinical outcomes following CRBI are influenced by organism type. This study aims to compare clinical outcomes following CRBI from Gram-positive and non-Gram-positive organisms. This was a retrospective cohort study of patients with kidney failure receiving haemodialysis (HD) via vascular catheters who had a documented episode of CRBI in Western Australia between 2005 and 2018. The associations between organism type, likelihood of hospitalization, catheter removal and death from CRBI were examined using adjusted logistic regression models. There were 111 episodes of CRBI in 99 patients (6.1 episodes per 1000-catheter-days at risk). Of the study cohort, 53 (48%) were male and 38 (34%) identified as Aboriginal or Torres Strait Islander. Gram-positive organisms were identified in 73 (66%) CRBI episodes, most commonly Staphylococcus aureus. Of those with non-Gram-positive CRBI, 9 (24%) were attributed to Pseudomonas aeruginosa. One-hundred and two (92%) episodes of CRBI required hospitalization and 15 (13%) patients died from CRBI. Compared with non-Gram-positive CRBI, Gram-positive CRBI was associated with an increased risk of hospitalization and catheter removal, with adjusted odds ratio of 9.34 (95% CI 1.28-68.03) and 3.47 (95% CI 1.25-9.67), respectively. There was no association between organism type and death from CRBI. Staphylococcus aureus remains the most common organism causing CRBI in HD patients. CRBI is associated with substantial morbidity, particularly CRBI attributed to Gram-positive organisms.