Vol.57 No.6 November 2009
Clinical and microbiological evaluation of extended-spectrum β-lactamase producing Escherichia coli bacteremia
1)Departments of Internal Medicine, Infectious Diseases, Kenwakai Otemachi Hospital, 15-1 Otemachi, Kokura-Kita, Fukuoka, Japan
2)Department of Urology, University of Occupational and Environmental Health
3)Department of Clinical Laboratory, Kyurin Corporation
4)Department of Clinical Laboratory, Kenwakai Otemachi Hospital
Abstract
Subjects were 10 consecutive patients with bacteremia caused by extended-spectrum β-lactamase(ESBL)-producing Escherichia coli seen from March to November 2009 and evaluated for microbiology data, clinical course, and clinical outcome. Their mean age was 82.3 years (59-103 years). Hospital acquired infection cases numbered 4, cases of admission from nursing homes 5, and strictly community-acquired infection cases 1. All strains were susceptible to meropenem, imipenem/cilastatin, piperacillin/tazobactam, flomoxef, and amikacin, followed by fosfomycin, faropenem, gentamicin, and trimethoprim/sulfamethoxazole. All strains were highly resistant to levofloxacin. Clinical presentation involved 3 cases of septic shock, 4 of severe sepsis, 2 of sepsis, and 1 of non-sepsis. Infection sources numbered 6 of urinary tract infections, 3 of primary sepsis, and 1 of cholangitis. ESBL strains numbered 4 of CTX-M-14 and 2 each of CTX-M14+CTX-M-2 and CTX-M3. In one case in which the isolated strain was not retained, polymerase chain reaction(PCR) was not done. Result of pulsed-field gel electrophoresis(PFGE) after cutting by Not I for eight strains, excluding case 2 and case 3, showed two pairs of identical patterns, but other strains differed. No outbreak from a single strain was seen. Crude mortality was 40% and 14-day mortality in the flomoxef group was 16.7%, not inferior to mortality in the imipenem/cilastatin group (50%). Flomoxef may therefore be a good choice for deescalation of ESBL producing E. coli bacteremia, although its narrow spectrum is not feasible for empiric therapy in hospital-acquired bacteremia. To reduce carbapenem consumption and prevent further resistance, it is important to evaluate flomoxef efficacy in treating ESBL-producing organisms.
Key word
Escherichia coli, Extended-spectrum β-lactamase, bacteremia, flomoxef
Received
May 25, 2009
Accepted
September 17, 2009
Jpn. J. Chemother. 57 (6): 502-507, 2009
