Safety and effectiveness of high-dose cefazolin in patients with high body weight: A retrospective cohort study

Background

Cefazolin is a commonly used antibiotic for the treatment of mild to severe infections. Despite the use of higher dose of cefazolin (3 g/dose) for surgical prophylaxis in patients with obesity, there is currently a paucity of data identifying the optimal dose to treat infections in this specific patient population.

Methods

This was a multicenter, retrospective cohort study of patients who received cefazolin at weight-based (up to 9 g/day) or standard doses (up to 6 g/day) for the treatment of bacteremia or skin and soft tissue infection (SSTI). Study groups were stratified by body weight and cefazolin dose received. Primary outcome was the composite of treatment-emergent adverse events (TEAEs) and secondary outcome was treatment failure rate.

Results

A total of 208 patients were included for study analysis. Fifty-nine patients had body weight >120 kg. Of these, 33 received high-dose cefazolin while 26 received standard doses. The remaining 149 patients had body weight of ≤120 kg and received standard doses. The occurrence of TEAEs did not differ across the 3 groups. The study also did not find any difference between the rate of treatment failure between groups.

Conclusions

High-dose cefazolin (9 g/day) for the treatment of bacteremia or SSTIs in patients with high body weight was safe and well tolerated. Larger studies are needed to further explore the benefit of high-dose cefazolin in improving clinical outcomes.

Risk Factors and Outcomes of Hospitalized Patients With Severe Coronavirus Disease 2019 (COVID-19) and Secondary Bloodstream Infections: A Multicenter Case-Control Study

Background

Coronavirus disease 2019 (COVID-19) has become a global pandemic. Clinical characteristics regarding secondary infections in patients with COVID-19 have been reported but detailed microbiology, risk factors and outcomes of secondary bloodstream infections (sBSI) in patients with severe COVID-19 have not been well described.

Methods

We performed a multicenter, case-control study including all hospitalized patients diagnosed with severe COVID-19 and blood cultures drawn from March 1, 2020 to May 7, 2020 at three academic medical centers in New Jersey, USA. Data collection included demographics, clinical and microbiologic variables, and patient outcomes. Risk factors and outcomes were compared between cases (sBSI) and controls (no sBSI).

Results

A total of 375 hospitalized patients were included. There were 128 sBSIs during the hospitalization. For the first set of positive blood cultures, 117 (91.4%) were bacterial and 7 (5.5%) were fungal. Those with sBSI were more likely to have altered mental status, lower mean percent oxygen saturation on room air, have septic shock and be admitted to the intensive care unit compared to the controls. In-hospital mortality was higher in those with a sBSI versus controls (53.1% vs 32.8%, p=0.0001).

Conclusions

We observed hospitalized adult patients with severe COVID-19 and sBSI had a more severe initial presentation, prolonged hospital course, and worse clinical outcomes. To maintain antimicrobial stewardship principles, further prospective studies are necessary to better characterize risk factors and prediction modeling to better understand when to suspect and empirically treat for sBSI in severe COVID-19.

1033. Effectiveness of a Physician-Driven Automated Antibiotic Time Out in the Setting of Gram-negative Bacteremia

Background

In an effort to minimize complications associated with over-utilization of antibiotics, many antimicrobial stewardship programs have incorporated an antibiotic time out (ATO). Despite the increasing adoption of the ATO, limited data are available to support its effectiveness. This study was designed to assess the impact of an automated ATO integrated into the electronic medical record (EMR) on the rate of antibiotic modification in patients receiving broad-spectrum antibiotic(s) for Gram-negative bacteremia (GNB).

Methods

This was a single-center retrospective cohort study of inpatients from January 2017 to June 2018 conducted at a large academic medical center. ATO was implemented on October 31, 2017. Adult patients with GNB who received at least 72 hours of a systemic antibiotic were included. Patients with neutropenia or polymicrobial infections were excluded. The primary outcome was the proportion of patients who received a modification of therapy within 24 hours of final culture results. Secondary outcomes included modification at any point in therapy, time to modification of therapy, time to de-escalation, and days of therapy of broad-spectrum antibiotics.

Results

There was a total of 88 patients who met inclusion criteria, 37 patients pre-ATO and 51 patients post-ATO. The primary outcome of modification of therapy within 24 hours of final culture results was not significantly different for patients in the pre-ATO and post-ATO groups (19% vs. 20%, P = 0.94, respectively). The secondary outcome of modification of therapy at any point in therapy was not significantly different between the two groups (62% vs. 66%, P = 0.67). Of the 47 patients who received a modification of therapy, the mean time to modification was significantly shorter in the post-ATO group (52.8 hours vs. 45.26 hours, P < 0.05,). All other secondary outcomes were not significantly different between study groups.

Conclusion

The ATO alert was not associated with a higher rate of antibiotic modification within 24 hours of culture results in patients with GNB, although there was a significant reduction in the time to antibiotic modification. Further efforts are needed to improve the time to modification and optimize antibiotic prescribing practices.

Disclosures

All authors: No reported disclosures.