OBJECTIVE: To evaluate risk factors and treatment outcomes of bloodstream infections caused by extended-spectrum beta-lactamase-producing Klebsiella pneumoniae (ESBL-KP). DESIGN: Retrospective case-control study. Stored blood isolates of K. pneumoniae were tested for ESBL production by NCCLS guidelines, double-disk synergy test, or both. SETTING: A 1,500-bed, tertiary-care university hospital and referral center. PATIENTS: Sixty case-patients with bacteremia due to ESB-KP were compared with 60 matched control-patients with non-ESBL-KP. RESULTS: There were no significant differences in age, gender, APACHE II score, or underlying diseases between the groups. Independent risk factors for infections caused by ESBL-KP were urinary catheterization, invasive procedure within the previous 72 hours, and an increasing number of antibiotics administered within the previous 30 days. Complete response rate, evaluated 72 hours after initial antimicrobial therapy, was higher among control-patients (13.3% vs 36.7%; P = .003). Treatment failure rate was higher among case-patients (35.0% vs 15%; P = .011). Overall 30-day mortality rate was 30% for case-patients and 28.3% for control-patients (P = .841). Case-patients who received imipenem or ciprofloxacin as a definitive antibiotic had 10.5% mortality. The mortality rate for initially ineffective therapy was no higher than that for initially effective therapy (9.1% vs 11.1%; P = 1.000), but statistical power was low for evaluating mortality in the absence of septic shock. CONCLUSION: For K. pneumoniae bacteremia, patients with ESBL-KP had a higher initial treatment failure rate but did not have higher mortality if antimicrobial therapy was appropriately adjusted in this study with limited statistical power.
OBJECTIVE: To evaluate risk factors and treatment outcomes of bloodstream infections caused by extended-spectrum beta-lactamase-producing Klebsiella pneumoniae (ESBL-KP). DESIGN: Retrospective case-control study. Stored blood isolates of K. pneumoniae were tested for ESBL production by NCCLS guidelines, double-disk synergy test, or both. SETTING: A 1,500-bed, tertiary-care university hospital and referral center. PATIENTS: Sixty case-patients with bacteremia due to ESB-KP were compared with 60 matched control-patients with non-ESBL-KP. RESULTS: There were no significant differences in age, gender, APACHE II score, or underlying diseases between the groups. Independent risk factors for infections caused by ESBL-KP were urinary catheterization, invasive procedure within the previous 72 hours, and an increasing number of antibiotics administered within the previous 30 days. Complete response rate, evaluated 72 hours after initial antimicrobial therapy, was higher among control-patients (13.3% vs 36.7%; P = .003). Treatment failure rate was higher among case-patients (35.0% vs 15%; P = .011). Overall 30-day mortality rate was 30% for case-patients and 28.3% for control-patients (P = .841). Case-patients who received imipenem or ciprofloxacin as a definitive antibiotic had 10.5% mortality. The mortality rate for initially ineffective therapy was no higher than that for initially effective therapy (9.1% vs 11.1%; P = 1.000), but statistical power was low for evaluating mortality in the absence of septic shock. CONCLUSION: For K. pneumoniae bacteremia, patients with ESBL-KP had a higher initial treatment failure rate but did not have higher mortality if antimicrobial therapy was appropriately adjusted in this study with limited statistical power.
Authors: Brad Spellberg; Martin Blaser; Robert J Guidos; Helen W Boucher; John S Bradley; Barry I Eisenstein; Dale Gerding; Ruth Lynfield; L Barth Reller; John Rex; David Schwartz; Edward Septimus; Fred C Tenover; David N Gilbert Journal: Clin Infect Dis Date: 2011-05 Impact factor: 9.079
Authors: Vicki L Collins; Dror Marchaim; Jason M Pogue; Judy Moshos; Suchitha Bheemreddy; Bharath Sunkara; Alex Shallal; Neelu Chugh; Sara Eiseler; Pragati Bhargava; Christopher Blunden; Paul R Lephart; Babar Irfan Memon; Kayoko Hayakawa; Odaliz Abreu-Lanfranco; Teena Chopra; L Silvia Munoz-Price; Yehuda Carmeli; Keith S Kaye Journal: Antimicrob Agents Chemother Date: 2012-01-30 Impact factor: 5.191