Bloodstream infections due to extended-spectrum beta-lactamase-producing Escherichia coli and Klebsiella pneumoniae: risk factors for mortality and treatment outcome, with special emphasis on antimicrobial therapy.
ABSTRACT This study was conducted to evaluate risk factors for mortality and treatment outcome of bloodstream infections due to extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli and Klebsiella pneumoniae (ESBL-EK). ESBL production in stored K. pneumoniae and E. coli blood isolates from Jan 1998 to Dec 2002 was phenotypically determined according to NCCLS guidelines and/or the double-disk synergy test. A total of 133 patients with ESBL-EK bacteremia, including 66 patients with ESBL-producing K. pneumoniae and 67 with ESBL-producing E. coli, were enrolled. The overall 30-day mortality rate was 25.6% (34 of 133). Independent risk factors for mortality were severe sepsis, peritonitis, neutropenia, increasing Acute Physiology and Chronic Health Evaluation II score, and administration of broad-spectrum cephalosporin as definitive antimicrobial therapy (P < 0.05 for each of these risk factors). In 117 of the 133 patients, excluding 16 patients who died within 3 days after blood culture sample acquisition, the 30-day mortality rates according to definitive antibiotics were as follows: carbapenem, 12.9% (8 of 62); ciprofloxacin, 10.3% (3 of 29); and others, such as cephalosporin or an aminoglycoside, 26.9% (7 of 26). When patients who received appropriate definitive antibiotics, such as carbapenem or ciprofloxacin, were evaluated, mortality in patients receiving inappropriate empirical antimicrobial therapy was found not to be significantly higher than mortality in those receiving appropriate empirical antimicrobial therapy (18.9 versus 15.5%; P = 0.666). Carbapenem and ciprofloxacin were the most effective antibiotics in antimicrobial therapy for ESBL-EK bacteremia. A delay in appropriate definitive antimicrobial therapy was not associated with higher mortality if antimicrobial therapy was adjusted appropriately according to the susceptibility results. Our data suggest that more prudent use of carbapenem as empirical antibiotic may be reasonable.
SourceAvailable from: Eleni Patrozou[Show abstract] [Hide abstract]
ABSTRACT: Infections due to Gram-negative bacteria exhibit seasonal trends, with peak infection rates during warmer months. We hypothesized that the likelihood of a bloodstream infection due to Gram-negative bacteria increases with proximity to the equator. We tested this hypothesis and identified geographical, climatic and social factors associated with this variability. We established a network of 23 international centers in 22 cities. Setting: De-identified results of positive blood cultures from 2007-2011 and data sources for geographic, climatic and socioeconomic factors were assembled for each center. Patients at the 23 centers with positive blood cultures. Due to variability in the availability of total culture volumes across sites, our primary outcome measure was the fraction of positive blood cultures that yielded Gram-negative bacteria; sources of variability in this outcome measure were explored using meta-regression techniques. The mean fraction of bacteremia associated with Gram-negative bacteria was 48.4% (range 26.4% to 61.8%). Although not all sites displayed significant seasonality, the overall P-value for seasonal oscillation was significant (P<0.001). In univariate meta-regression models, temperature, latitude, latitude squared, longitude, per capita gross domestic product and percent of gross domestic product spent on healthcare were all associated with the fraction of bacteremia due to Gram-negative bacteria. In multivariable models, only percent of gross domestic product spent on healthcare and distance from the equator (ie. latitude squared) were significantly associated with the fraction of bacteremia due to Gram-negative bacteria. The likelihood of bacteremia due to Gram-negative bacteria varies markedly between cities, in a manner that appears to have both geographic (latitude) and socioeconomic (proportion gross domestic product devoted to health spending) determinants. Thus, the optimal approach to initial management of suspected bacteremia may be geographically specific. The rapid emergence of highly antibiotic-resistant Gram-negative pathogens may have geographically specific impacts.PLoS ONE 12/2014; 9(12):e114548. DOI:10.1371/journal.pone.0114548 · 3.53 Impact Factor
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ABSTRACT: We investigated the clinical usefulness of the revised 2010 Clinical and Laboratory Standards Institute (CLSI) breakpoints for Escherichia coli and Klebsiella spp. Of 2,623 patients with bacteremia caused by E. coli or Klebsiella spp., 573 who had been treated appropriately with cephalosporin based on the CLSI 2009 guidelines were enrolled. There were no differences in the rates of treatment failure or mortality between the appropriately and inappropriately treated groups according to the CLSI 2010 guidelines. Additionally, in the matched case-control analysis, the treatment failure rate was higher in bacteremic patients with extended-spectrum β-lactamase- (ESBL-) producing but cephalosporin-susceptible organisms than in those with ESBL-nonproducing isolates when patients with urinary tract infections were excluded (44% and 0%, resp., ). In patients with bacteremia caused by E. coli or Klebsiella spp., the revised CLSI 2010 guidelines did not lead to poorer outcomes. However, ESBL production appeared to be associated with poor clinical outcomes in patients with bacteremia from sources other than the urinary tract.01/2015; 2015:1-8. DOI:10.1155/2015/831074
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ABSTRACT: The aim of this study is to determine the prevalence of extended spectrum beta-lactamase (ESBL) producing Klebsiella pneumoniae strains isolated from blood in children and their susceptibility to antimicrobial drugs commonly used in the therapy. The study was conducted at the Institute of Public Health of Vojvodina Province, Serbia, in a two-year period, from January 2009 to December 2010. A total of 424 non-duplicate strains were isolated from the blood of pediatric patients hospitalized in various wards in the Institute of Health Care of Children and Youth of Vojvodina Province. Fifty isolates of Klebsiella pneumoniae were reported. The frequency of isolation of Klebsiella pneumoniae was 27/222 (12.2%) and 23/202 (11.3%) isolates in 2009 and 2010, respectively. There was a high prevalence of ESBL-producing Klebsiella pneumoniae, 76% (38/50), and 17 isolates (44.7%) were multidrug resistant (MDR). Further drug resistance surveillance in hospitals and the molecular characterization of ESBL-positive isolates in our country is necessary.Archives of Biological Sciences 01/2012; 64(4):1339-1347. DOI:10.2298/ABS1204339M · 0.61 Impact Factor