Effect of antimicrobial therapy on mortality in 377 episodes of Enterobacter spp. bacteraemia.
OBJECTIVE
The impact of appropriate antimicrobial therapy and antimicrobial resistance on the outcome of bacteraemia due to Enterobacter spp. remains unclear. The aim of our study was to evaluate the effect of antimicrobial therapy in 377 consecutive episodes of Enterobacter bacteraemia.


METHODS
This includes retrospective analysis of a prospectively collected cohort. Clinical variables recorded were age, underlying diseases, use of corticosteroids, prognosis of underlying disease according to the McCabe and Jackson criteria, source of bacteraemia, need for mechanical ventilation, empirical antibiotic treatment, definitive treatment, antimicrobial susceptibility, presentation with septic shock and 30 day mortality rate. Univariate and multivariable analyses were performed to analyse the influence of antibiotic treatment and cephalosporin resistance on mortality.


RESULTS
Between 1991 and 2006, 377 episodes of bacteraemia due to Enterobacter spp. (2.2%) were recorded. The frequency of Enterobacter bacteraemia significantly increased over these years. The overall mortality rate was 12.5% (47 of 377). Independent factors associated with 30 day mortality in patients with monomicrobial bacteraemia were rapidly fatal prognosis when compared with non-fatal prognosis, presentation with septic shock, patient under mechanical ventilation and unknown source of infection. The only factor independently associated with lower 30 day mortality was the empirical use of piperacillin/tazobactam.


CONCLUSIONS
Enterobacter spp. are an increasing cause of bacteraemia. The empirical use of piperacillin/tazobactam was independently associated with a lower 30 day mortality rate.
Marcos
Miguel
M
Department of Infectious Diseases, Hospital Clinic of Barcelona, C/ Villarroel 170, Barcelona 08036, Spain. migmarmar10@hotmail.com
Iñurrieta
Amaia
A
Soriano
Alex
A
Martínez
José A
JA
Almela
Manel
M
Marco
Francesc
F
Mensa
Josep
J
D000328:Adult; D000368:Aged; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D016470:Bacteremia / Q000188:drug therapy* / Q000453:epidemiology / Q000382:microbiology / Q000401:mortality*; D004754:Enterobacter / Q000302:isolation & purification*; D004756:Enterobacteriaceae Infections / Q000188:drug therapy* / Q000453:epidemiology / Q000382:microbiology / Q000401:mortality*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D010397:Penicillanic Acid / Q000031:analogs & derivatives / Q000627:therapeutic use; D010878:Piperacillin / Q000627:therapeutic use; D000077725:Piperacillin, Tazobactam Drug Combination; D015995:Prevalence; D012307:Risk Factors; D016896:Treatment Outcome; D018440:beta-Lactam Resistance
D000900:Anti-Bacterial Agents; D000077725:Piperacillin, Tazobactam Drug Combination; D010397:Penicillanic Acid; D010878:Piperacillin