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182. Appropriateness of Treatment Duration for S. aureus Bacteremia (SAB)

Abstract Background An algorithm-based guide to optimal treatment duration in staphylococcus bacteremia demonstrated a non-inferior rate of clinical success compared with standard of care. The purpose of this descriptive study was to assess appropriateness of staphylococcus bacteremia duration of therapy according to the SAB treatment algorithm. Methods IRB approved, retrospective cohort describing antibiotic use in S. aureus bacteremia across a health system from January to March 2019. Patients were included if they had at least one blood culture with S. aureus. Exclusion criteria included transfer from outside hospital, concurrent osteomyelitis diagnosis, and death within 72 hours of positive culture. The primary outcome was the appropriate duration of antibiotics for uncomplicated SAB. Secondary outcomes included clinical failure, antibiotic adverse effects, 90-day mortality, and hospital length of stay. Results A total of 59 patients were included. The median age was 66 years old and 22 patients (37.3%) were female. Diagnosis: uncomplicated SAB 28 (47.5%) and complicated SAB 31 (52.5%); MRSA 32 (%) and MSSA 27 (%). Infectious Diseases Consultation 56 (94.9%). 4 patients died before treatment duration was determined. Breakdown of treatment durations and clinical failures are listed in Tables 1. Appropriate duration occurred in 9 (32.1%) of patients with SAB. Overall, 14 patients experiences antibiotic adverse effects, 11 which occurred in antibiotic use for ≥4 weeks, 4 occurred in patients with uncomplicated SAB treated for ≥4 weeks. Breakdown of adverse effects: acute kidney injury 9, myositis 1, rash 1, nausea/vomiting 1, anaphylaxis 1, hypersensitivity pneumonitis 1. Conclusion Excess treatment duration for uncomplicated SAB was common (16%), in this study, inconsistent with best practice recommendations. 79% of adverse effects occurred in patients who received a ≥4 week course. The results of this study suggest more efforts are needed to implement contemporary evidence-based treatment duration algorithms for uncomplicated SAB to minimize unnecessary antibiotic harm. Disclosures All authors: No reported disclosures.


Background.
Klebsiella species (KS) bloodstream infection (BSI) is often caused by K. pneumoniae (KP). K. oxytoca (KO) is emerging and implicated in antibiotic-associated right-sided colitis. We compared the clinical and microbiological characteristics of KP and KO.
Methods. We reviewed blood culture (BC) results (January 1, 2010-December 31, 2017), selected patients with KS in ≥1 BC, reviewed their medical records, abstracted patient demographics, source of bacteremia, antibiotics susceptibility, and outcome. Each patient was counted once. We compared KP and KO cases. All differences were assessed by the chi-square test and regression analysis, using SPSS.

Conclusion.
KO and KP BSI differ in the type of host and source, suggesting different colonization dynamics. KO remains antibiotic-susceptible but might be cefazolin less susceptible. Prospective studies are needed to confirm differential cephalosporin susceptibility and delineate host-pathogen interactions.
Disclosures. All authors: No reported disclosures. Background. Bacteremia due to Pseudomonas aeruginosa is associated with high mortality and inappropriate initial antimicrobial therapy leads to worse outcomes. We aimed to analyze clinical characteristics of P. aeruginosa bacteremia and risk factors for antibiotic resistance and investigate their antimicrobial susceptibility trends.

Antimicrobial Susceptibility Trends and Risk Factors for Antibiotic
Methods. We retrospectively reviewed the medical records of patients with P. aeruginosa bacteremia admitted to a tertiary hospital between January 2009 and March 2019.
Conclusion. The identification of risk factors for antibiotic resistance and analysis of antibiotics susceptibility are useful for early initiation of appropriate antibiotics in patients with P. aeruginosa bacteremia.
Disclosures. All authors: No reported disclosures. Background.

Appropriateness of Treatment Duration for S. aureus Bacteremia (SAB)
An algorithm-based guide to optimal treatment duration in staphylococcus bacteremia demonstrated a non-inferior rate of clinical success compared with standard of care. The purpose of this descriptive study was to assess appropriateness of staphylococcus bacteremia duration of therapy according to the SAB treatment algorithm.
Methods. IRB approved, retrospective cohort describing antibiotic use in S. aureus bacteremia across a health system from January to March 2019. Patients were included if they had at least one blood culture with S. aureus. Exclusion criteria included transfer from outside hospital, concurrent osteomyelitis diagnosis, and death within 72 hours of positive culture. The primary outcome was the appropriate duration of antibiotics for uncomplicated SAB. Secondary outcomes included clinical failure, antibiotic adverse effects, 90-day mortality, and hospital length of stay.
Conclusion. Excess treatment duration for uncomplicated SAB was common (16%), in this study, inconsistent with best practice recommendations. 79% of adverse effects occurred in patients who received a ≥4 week course. The results of this study suggest more efforts are needed to implement contemporary evidence-based treatment duration algorithms for uncomplicated SAB to minimize unnecessary antibiotic harm.

Disclosures. All authors:
No reported disclosures.