1289. The Challenge of Treating Community-Associated Enterobacterales Infections in a Middle-Income Country: Data from SMART 2018-2019

Abstract Background Antimicrobial stewardship programs have been used widely in hospital settings due to the rise of resistant bacteria, antibiotic toxicities, and costs. Nevertheless, few efforts are done to prevent the rising antimicrobial resistance in community settings. The aim of our study was to evaluate the antimicrobial resistance from Enterobacterales community- and hospital-acquired infections in Southern Brazil. Methods A total of 272 Enterobacterales isolates (i.e., Escherichia coli, Klebsiella spp., Citrobacter spp., Enterobacter spp., Serratia spp., Proteus spp., and Providencia) were collected from 2018 and 2019. Broth microdilution method was used to determine minimum inhibitory concentrations for ceftriaxone, cefepime, levofloxacin, amikacin and ertapenem. Molecular evaluation of beta-lactamases (ESBLs, AmpC, and KPC) was also performed. Results Ninety-three, and a hundred and seventy-nine isolates were from community- and hospital-acquired infections, respectively. Similar MIC distribution was found between community and hospital settings (Table 1). Levofloxacin MIC of 8mg/L occurred in 38.7% (n=36) and 30.7% (n=55) of isolates from community- and hospital-acquired infections, respectively (Figure 1). Ceftriaxone MIC of 16mg/L occurred in 39.7%(n=37) and 39.1% (n=70) of isolates from community- and hospital-acquired infections, respectively (Figure 1). At last, cefepime MIC of 32mg/L occurred in 22% (n=21) and 25% (n=46) of isolates from community- and hospital-acquired infections, respectively. The following beta-lactamases were found in isolates from community-acquired group, ACT-MIR, CTX-M, SHV and TEM; while beta-lactamases from the hospital-acquired group were ACT-MIR, CMY II, KPC-2, CTX-M, SHV and TEM. Table 1. Enterobacterales ceftriaxone, cefepime, levofloxacin, amikacin and ertapenem minimum inhibitory concentrations (mg/L) distribution from community- and hospital-settings. Figure 1. Enterobacterales ceftriaxone and levofloxacin minimum inhibitory concentrations (mg/L) distribution from community- and hospital-settings. Conclusion Similar antimicrobials resistances were found in Enterobacterales from community- and hospital-acquired infections. New anti-infective agents are needed urgently to treat pathogens from the community-acquired infections and hospitals that have resistance to the first line regimen. Additionally, community antimicrobial stewardship programs are required. Disclosures All Authors: No reported disclosures


Anti-infective research lab
Session: P-72. Resistance Mechanisms Background. Eravacycline (ERV) is approved in the United States (US) for the treatment of complicated intra-abdominal infections in adults. We aimed to evaluate the independent predictors of clinical success in patients treated with ERV for various infections.
Methods. Multicenter, retrospective, observational study conducted from September, 2018 to April, 2021. We included adults treated with ERV for ≥ 72hours. Clinical success was defined as 30-day survival, lack of 30-day infection-recurrence, and resolution of infection signs/symptoms. All outcomes were measured from ERV initiation. Multivariable logistic regression (MLR) was performed to identify independent predictors of clinical success. Clinically relevant variables were selected for model entry based on bivariate comparisons (P< 0.2) in a backward fashion.
Conclusion. Although most ERV treated patients experienced clinical success, factors independently associated with higher clinical success are crucial to consider for optimum antibiotic selection.
Disclosures Background. Antimicrobial stewardship programs have been used widely in hospital settings due to the rise of resistant bacteria, antibiotic toxicities, and costs. Nevertheless, few efforts are done to prevent the rising antimicrobial resistance in community settings. The aim of our study was to evaluate the antimicrobial resistance from Enterobacterales community-and hospital-acquired infections in Southern Brazil.
Results. Ninety-three, and a hundred and seventy-nine isolates were from community-and hospital-acquired infections, respectively. Similar MIC distribution was found between community and hospital settings (Table 1). Levofloxacin MIC of 8mg/L occurred in 38.7% (n=36) and 30.7% (n=55) of isolates from community-and hospital-acquired infections, respectively (Figure 1). Ceftriaxone MIC of 16mg/L occurred in 39.7%(n=37) and 39.1% (n=70) of isolates from community-and hospital-acquired infections, respectively (Figure 1). At last, cefepime MIC of 32mg/L occurred in 22% (n=21) and 25% (n=46) of isolates from community-and hospital-acquired infections, respectively. The following beta-lactamases were found in isolates from community-acquired group, ACT-MIR, CTX-M, SHV and TEM; while beta-lactamases from the hospital-acquired group were ACT-MIR, CMY II, KPC-2, CTX-M, SHV and TEM. Table 1. Enterobacterales ceftriaxone, cefepime, levofloxacin, amikacin and ertapenem minimum inhibitory concentrations (mg/L) distribution from community-and hospital-settings. Conclusion. Similar antimicrobials resistances were found in Enterobacterales from community-and hospital-acquired infections. New anti-infective agents are needed urgently to treat pathogens from the community-acquired infections and hospitals that have resistance to the first line regimen. Additionally, community antimicrobial stewardship programs are required.

Ceftazidime-Avibactam Resistance Report in a Third Level Hospital in Mexico City
Aaron Molina, MD 1 ; Abigail Salinas-Hernandez, n/a 2 ; Alejandro Olmedo-Reneaum, Background. The surge of resistant Gram-negative organisms has been worrying infectious disease physicians and physicians in general because of the lack of a large number of antibiotics to which these organisms remain susceptible. Ceftazidime-Avibactam (CAZ-AVI) is a drug approved by the FDA to treat complicated urinary tract infections (cUTI), complicated intra-abdominal infections (cIAIs) in combination with metronidazole, and recently for the treatment of nosocomial pneumonia. Worldwide resistance rates of Enterobacteriaceae to CAZ-AVI have been reported below 2.6%, and 4-8% for Pseudomonas aeruginosa. The FDA, CLSI, and EUCAST assigned the clinical breakpoints of susceptibility: MIC < /=8 mg/liter susceptible, and >/=8mg/liter, resistant. In Mexico, CAZ-AVI was approved in 2018, and its cost is very high compared to other antimicrobials, so its use is limited in very specific cases. The resistance rates to this antibiotic in the Mexican population remain largely unknown.
Methods. We tested 106 specimens for susceptibility to ceftazidime-avibactam using the disk Kirby-Bauer method. The inhibition zone diameter was determined in all cases and we considered the organism susceptible when the inhibition zone diameter was >=21 mm, and resistant with an inhibition zone diameter < = 20 mm.
Conclusion. The ceftazidime-avibactam resistance among Gram-negative bacteria in our study is similar to the one reported in other international studies. We need more studies in our population to know the nationwide resistance to this antibiotic.
Disclosures. All Authors: No reported disclosures