The Clinical Evaluation of Third-generation Cephalosporins As Definitive Therapy for Enterobacter spp. and Klebsiella aerogenes Bacteremia.

Objective Third-generation cephalosporins (3GCs) may be susceptible in vitro to Enterobacter spp. and Klebsiella aerogenes. However, treatment with mainly fourth-generation cephalosporins or carbapenems is currently recommended. Diversification of antimicrobial agents in therapy is required to avoid the selection pressure of resistant organisms by broad-spectrum antimicrobial agents. This study investigated the clinical efficacy of 3GC therapy for Enterobacter spp. and Klebsiella aerogenes bacteremia in a multicenter, retrospective, observational study. Methods Patients with Enterobacter spp. or Klebsiella aerogenes detected in blood cultures and treated with a susceptible antimicrobial agent were included in the study. Propensity score matching was performed to align patient background bases, and clinical outcomes between the 3GC and non-3GC groups were compared. Treatment success was defined as having no need for treatment escalation or the addition of other antimicrobial agents, no recurrence, or no death within 30 days. Results The study included 188 cases, of which 57 and 131 were included in the 3GC and non-3GC treatment groups, respectively; 53 patients in each group were matched by propensity score matching. There were no significant differences between groups in rates of switching to a susceptible antimicrobial or adding another agent, relapse within 30 days, or death within 30 days. In the 3GC group, source control was associated with favorable clinical outcomes. Conclusion Definitive 3GC therapy for susceptible Enterobacter spp. and Klebsiella aerogenes bacteremia is as clinically effective and valuable a targeted therapy as non-3GC therapy and can be implemented under conditions in which infection source control measures are in place.

Impact of coronavirus disease 2019 on infectious disease treatment and infection control at a tertiary hospital in Japan.

INTRODUCTION: Coronavirus disease 2019 (COVID-19) has greatly impacted medical care practices. Although the effects on infectious disease treatment and infection control, such as antimicrobial resistance, have been specified, very few reports exist on the specific effects of COVID-19. METHODS: We investigated the effects of COVID-19 on daily medical practices at a tertiary hospital in Japan by comparing the use of hand sanitizers, the detection of bacteria from blood cultures, and the amount dose of antibacterial drugs used for one year before (April 2019 to March 2020, fiscal year 2019.) and after COVID-19 admissions began (April 2020 to March 2021, fiscal year 2020). RESULTS: The use of hand sanitizers increased by 1.4-3 times during the year after COVID-19 admissions began; the incidence of methicillin-susceptible Staphylococcus aureus and all S. aureus detected in blood cultures reduced in all departments. No decrease was observed in the usage of all antibacterial drugs; rather, the usage of all antibacterial drugs tended to increase in all departments. Therefore, no significant change was observed in the detection of drug-resistant bacteria and the trends of antibacterial drug use based on the acceptance of COVID-19 patients. CONCLUSIONS: The prevalence of drug-resistant bacteria and trends of antibacterial drug use remained unchanged despite the increased use of hand sanitizers due to the admission of patients with COVID-19.

The intervention by an antimicrobial stewardship team can improve clinical and microbiological outcomes of resistant gram-negative bacteria.

Antibiotic stewardship (AS) improves patient outcomes and rates of antibiotic susceptibilities. However, the long-term effect of AS programs (ASPs) on mortality is unclear. This study aimed to assess the impact of bedside interventions by an AS team (AST) on clinical and microbiological outcomes. This retrospective study enrolled patients with bloodstream infections (BSI) and long-term use of broad-spectrum antibiotics (more than 7 days). The main outcomes were 30-day and in-hospital mortality of patients with BSI. The secondary outcomes were the day of therapy (DOT) and susceptibility of antipseudomonal agents. Cases were classified into two groups: the pre-ASP group comprised cases between 2011 and 2013 and the post-ASP group, between 2014 and 2016. The outcomes were then compared between the two groups. Among the patients with all BSI (n = 1187), no significant differences in 30-day mortality were observed between those in the pre-ASP and post-ASP groups. However, in-hospital mortality was significantly lower in the post-ASP group than that in the pre-ASP group (24.8% vs. 18.0%; P = 0.004). Furthermore, the 30-day and in-hospital mortality of resistant gram-negative bacteraemia was significantly lower (20.4% vs.10.5%; P = 0.04 and 28.0% vs.16.1%; P = 0.03). The DOT of broad-spectrum antibiotics decreased except that of tazobactam/piperacillin. The susceptibilities of tazobactam/piperacillin, ceftazidime, cefepime, sulbactam/cefoperazone, gentamicin, ciprofloxacin levofloxacin, imipenem and meropenem were significantly better. Interventions by the AST can improve the clinical and microbiological outcomes, especially resistant gram-negative bacteria. Furthermore, this effect of our ASP can continue for a long term.

Clinical Characteristics and Low Susceptibility to Daptomycin in Enterococcus faecium Bacteremia.

Enterococcus faecium has high levels of resistance to multiple antibiotics, and the mortality due to E. faecium bacteremia is high. Accordingly, E. faecium strains with low susceptibility to daptomycin are a concern in clinical practice. This study assessed the predictive factors and prognosis of patients with bacteremia due to E. faecium as well as the antimicrobial susceptibility, particularly to daptomycin, among E. faecium isolates. The medical records of patients admitted to Osaka City University Hospital with E. faecalis (n = 60) and E. faecium (n = 48) bacteremia between January 2011 and March 2016 were retrospectively reviewed. The E. faecalis group (mean age: 62.0 years) included 22 women, and the E. faecium group (mean age: 59.1 years) included 19 women. Predictive factors for infection, prognosis, and isolate antimicrobial susceptibilities were evaluated. The mean Sequential Organ Failure Assessment score and mortality rate did not differ between the two groups. The independent predictors of E. faecium bacteremia in multivariate analysis included quinolone use (p = 0.025), malignancy (p = 0.021), and prolonged hospitalization (p = 0.016). Cardiovascular disease was associated with a reduced risk of E. faecium bacteremia (p = 0.015). Notably, the percentage of E. faecium isolates with low daptomycin susceptibility was higher than that of E. faecalis (8.5% vs. 0%, p = 0.036). Thus, E. faecium should be considered when administering antibiotic therapy to patients with a history of these predictors. Furthermore, the use of daptomycin should be avoided in case of E. faecium with low susceptibility to daptomycin.

Clinical Characteristics of Methicillin-resistant Coagulase-negative Staphylococcal Bacteremia in a Tertiary Hospital.

Objective Coagulase-negative staphylococci are among the most frequently isolated microorganisms in blood cultures. The aim of this study was to assess [1] the clinical characteristics of methicillin-resistant, coagulase-negative staphylococci bacteremia and [2] the susceptibility of the isolated bacteria to glycopeptides. Methods We retrospectively reviewed the medical records of 70 patients from whom methicillin-resistant coagulase-negative staphylococci had been isolated at Osaka City University Hospital between January 2010 and December 2013. We evaluated the patients' background, severity and prognosis of the disease, and the susceptibility of the isolated methicillin-resistant coagulase-negative staphylococci to glycopeptides. Results Out of the 70 patients tested, 28 (40.0%) had leukemia, and 36 (51.4%) had been treated for febrile neutropenia. Infection with Staphylococcus epidermidis accounted for 78.6% of patients. Thirty-nine cases (55.7%) were related to intravascular catheters, and 39 (55.7%) were treated using teicoplanin as a first-line therapy. The 30-day mortality rate was 4.3%. Regarding susceptibility, 20% of all isolates were non-susceptible to teicoplanin. According to multivariate analyses, it was observed that premedication using glycopeptides was independently associated with teicoplanin non-susceptibility (p=0.03; hazard ratio = 5.64; 95% confidence interval, 1.16-26.76). Conclusion Our results suggest that clinicians must use glycopeptides appropriately to prevent the development of further antibiotic resistance in methicillin-resistant coagulase-negative staphylococci.