Risk factors for bloodstream infection caused by extended-spectrum β-lactamase-producing Escherichia coli and Klebsiella pneumoniae: A focus on antimicrobials including cefepime.
BACKGROUND
Extended-spectrum β-lactamase (ESBL)-producing pathogens represent increasing challenges to physicians because of rising prevalence, high mortality, and challenging treatment. Identifying high risks and early appropriate therapy is critical to favorable outcomes.


METHODS
This is a 5-year retrospective case-case-control study performed at the Detroit Medical Center on adult patients with bloodstream infection (BSI) caused by ESBL-producing and non-ESBL-producing Escherichia coli or Klebsiella pneumoniae, each compared with uninfected controls. Data were collected from December 2004-August 2009. Multivariate analysis was performed using logistic regression.


RESULTS
Participants included 103 patients with BSI caused by ESBL-producing pathogens and 79 patients with BSI caused by pathogens that did not produce ESBLs. The mean age of patients in the ESBL group was 67 years; of the patients, 51% were men, 77% were black, and 38% (n = 39) died in hospital. The mean age of patients in the non-ESBL group was 58 years; of the patients, 51% were men, 92% were black, and 22% (n = 17) died in hospital. On multivariate analysis, predictors of BSI caused by ESBL-producing pathogens included central venous catheter (odds ratio [OR], 29.4; 95% confidence interval [CI], 3.0-288.3), prior β-lactam-/β-lactamase-inhibitor therapy (OR, 28.1; 95% CI, 1.99-396.5), and prior cefepime therapy (OR, 22.7; 95% CI, 2.7-192.4). The only risk factor for BSI caused by non-ESBL-producing pathogens was urinary catheter insertion (OR, 18.2; 95% CI, 3.3-100.3).


CONCLUSIONS
Prior antimicrobial therapy, particularly with β-lactam, was the strongest unique risk factor for BSI caused by ESBL-producing E coli or K pneumoniae.
Wayne State University, Detroit, MI.
Teena
T
Chopra
Wayne State University, Detroit, MI.
Dror
D
Marchaim
Department of Infectious Diseases, William Beaumont Hospital, Royal Oak, MI.
Paul C
PC
Johnson
Wayne State University, Detroit, MI. Electronic address: ichalana@med.wayne.edu.
Indu K
IK
Chalana
Wayne State University, Detroit, MI.
Zeinab
Z
Tamam
Wayne State University, Detroit, MI.
Mazin
M
Mohammed
Wayne State University, Detroit, MI.
Shatha
S
Alkatib
Wayne State University, Detroit, MI.
Ryan
R
Tansek
Wayne State University, Detroit, MI.
Khawar
K
Chaudhry
Wayne State University, Detroit, MI.
Jing J
JJ
Zhao
Detroit Medical Center, Detroit, MI.
Jason M
JM
Pogue
Wayne State University, Detroit, MI.
Keith S
KS
Kaye
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D016470:Bacteremia / Q000453:epidemiology* / Q000382:microbiology; D016022:Case-Control Studies; D000077723:Cefepime; D002511:Cephalosporins / Q000627:therapeutic use*; D004926:Escherichia coli / Q000201:enzymology* / Q000302:isolation & purification; D004927:Escherichia coli Infections / Q000453:epidemiology* / Q000382:microbiology; D005260:Female; D006761:Hospitals; D006801:Humans; D007710:Klebsiella Infections / Q000453:epidemiology* / Q000382:microbiology; D007711:Klebsiella pneumoniae / Q000201:enzymology* / Q000302:isolation & purification; D008297:Male; D008824:Michigan / Q000453:epidemiology; D008875:Middle Aged; D012189:Retrospective Studies; D012307:Risk Factors; D001618:beta-Lactamases / Q000378:metabolism*
D000900:Anti-Bacterial Agents; D002511:Cephalosporins; D000077723:Cefepime; D001618:beta-Lactamases
Antimicrobials; Bloodstream; Bloodstream infection; Cefepime; E coli; ESBL; Escherichia coli; Extended-spectrum β-lactamase; K pneumoniae; Klebsiella pneumoniae; Risk factors