Extended spectrum Beta-lactamase producing Escherichia coli and Klebsiella pneumoniae bacteremia: Risk factors and outcome in the Eastern Region of Saudi Arabia

To study the risk factors for bacteremia caused by Escherichia coli (E. coli) or Klebsiella pneumoniae (K. pneumoniae) producing extended-spectrum beta-lactamase (ESBL) and their outcome. A case-control study was conducted in King Abdul-Aziz National Guard Hospital, Al-Ahsa, Kingdom of Saudi Arabia from January 2006 through December 2007. All adult patients for whom culture results were positive for E. coli or K. pneumoniae were eligible. Twenty-nine patients with ESBL producing bacteremia (cases) were compared with 80 patients with non-ESBL producing bacteremia controls. Hospital mortality was the primary end point. Univariable and multivariable logistic regression were performed to analyze risk factors for ESBL bacteremia and its 30-day mortality. A total of 109 patients with bacteremia were enrolled that included 29 cases and 80 controls. Forty-nine percent of the patients were male. The mean age was 60.2+/-21.1 years. Nosocomial infection was the only independent risk factor for bacteremia due to ESBL-producing pathogens (odds ratio [OR] 3.40, 95% confidence interval [CI] 1.14-8.44, p=0.02). Overall 30-day mortality was 22%, and was similar in both groups. The nosocomial infection (OR 3.20, 95% CI 1.48-6.94, p=0.01), presentation with septic shock (OR 48.88, 95% CI 6.01-397.32, p=0.004), and intensive care unit care (OR 7.40, 95% CI 1.94 -28.34, p=0.001) were the independent risk factors for 30-day mortality. The ESBL rate is high in our study among the bacteremic patients. Nosocomial infection is identified both as a risk factor for ESBL bacteremia and mortality.