Clinical impact of fluoroquinolone-resistant Escherichia coli in the fecal flora of hematological patients with neutropenia and levofloxacin prophylaxis.
BACKGROUND
Fluoroquinolone prophylaxis in patients with neutropenia and hematological malignancies is said to be effective on febrile netropenia (FN)-related infection and mortality; however, the emergence of antibiotic resistance has become a concern. Ciprofloxacin and levofloxacin prophylaxis are most commonly recommended. A significant increase in the rate of quinolone-resistant Escherichia coli in fecal flora has been reported following ciprofloxacin prophylaxis. The acquisition of quinolone-resistant E. coli after levofloxacin use has not been evaluated.


METHODS
We prospectively examined the incidence of quinolone-resistant E. coli isolates recovered from stool cultures before and after levofloxacin prophylaxis in patients with neutropenia from August 2011 to May 2013. Some patients received chemotherapy multiple times.


RESULTS
In this trial, 68 patients were registered. Levofloxacin-resistant E. coli isolates were detected from 11 and 13 of all patients before and after the prophylaxis, respectively. However, this was not statistically significant (P = 0.65). Multiple prophylaxis for sequential chemotherapy did not induce additional quinolone resistance among E. coli isolates. Interestingly, quinolone-resistant E. coli, most of which were extended-spectrum β-lactamase (ESBL) producers, were already detected in approximately 20% of all patients before the initiation of prophylaxis. FN-related bacteremia developed in 2 patients, accompanied by a good prognosis.


CONCLUSIONS
Levofloxacin prophylaxis for neutropenia did not result in a significant acquisition of quinolone-resistant E. coli. However, we detected previous colonization of quinolone-resistant E. coli before prophylaxis, which possibly reflects the spread of ESBL. The epidemic spread of resistant E. coli as a local factor may influence strategies toward the use of quinolone prophylaxis.
Medicine and Biosystemic Science, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan.
Yong
Y
Chong
Medicine and Biosystemic Science, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan.
Shinji
S
Shimoda
Department of Clinical Laboratory, Hara-Sanshin Hospital, Fukuoka, Japan.
Hiroko
H
Yakushiji
Department of Blood and Marrow Transplantation, Hara-Sanshin Hospital, Fukuoka, Japan.
Yoshikiyo
Y
Ito
Department of Blood and Marrow Transplantation, Hara-Sanshin Hospital, Fukuoka, Japan.
Takatoshi
T
Aoki
Medicine and Biosystemic Science, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan.
Toshihiro
T
Miyamoto
Department of Blood and Marrow Transplantation, Hara-Sanshin Hospital, Fukuoka, Japan.
Tomohiko
T
Kamimura
Center for the Study of Global Infection, Kyushu University Hospital, Fukuoka, Japan.
Nobuyuki
N
Shimono
Medicine and Biosystemic Science, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan.
Koichi
K
Akashi
D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D024881:Drug Resistance, Bacterial / Q000187:drug effects; D004926:Escherichia coli / Q000187:drug effects* / Q000302:isolation & purification / Q000502:physiology; D004927:Escherichia coli Infections / Q000150:complications / Q000382:microbiology / Q000517:prevention & control*; D064147:Febrile Neutropenia / Q000150:complications*; D005243:Feces / Q000382:microbiology*; D005260:Female; D019337:Hematologic Neoplasms / Q000150:complications*; D054884:Host-Pathogen Interactions / Q000187:drug effects; D006801:Humans; D064704:Levofloxacin / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D016896:Treatment Outcome
D000900:Anti-Bacterial Agents; D064704:Levofloxacin