Metallo-beta-lactamase-producing gram-negative bacilli: laboratory-based surveillance in cooperation with 13 clinical laboratories in the Kinki region of Japan.
A total of 19,753 strains of gram-negative rods collected during two 6-month periods (October 2000 to March 2001 and November 2001 to April 2002) from 13 clinical laboratories in the Kinki region of Japan were investigated for the production of metallo-beta-lactamases (MBLs). MBLs were detected in 96 (0.5%) of the 19,753 isolates by the broth microdilution method, the 2-mercaptopropionic acid inhibition test, and PCR and DNA sequencing analyses. MBL-positive isolates were detected in 9 of 13 laboratories, with the rate of detection ranging between 0 and 2.6% for each laboratory. Forty-four of 1,429 (3.1%) Serratia marcescens, 22 of 6,198 (0.4%) Pseudomonas aeruginosa, 21 of 1,108 (1.9%) Acinetobacter spp., 4 of 544 (0.7%) Citrobacter freundii, 3 of 127 (2.4%) Providencia rettgeri, 1 of 434 (0.2%) Morganella morganii, and 1 of 1,483 (0.1%) Enterobacter cloacae isolates were positive for MBLs. Of these 96 MBL-positive strains, 87 (90.6%), 7 (7.3%), and 2 (2.1%) isolates carried the genes for IMP-1-group MBLs, IMP-2-group MBLs, and VIM-2-group MBLs, respectively. The class 1 integrase gene, intI1, was detected in all MBL-positive strains, and the aac (6')-Ib gene was detected in 37 (38.5%) isolates. Strains with identical PCR fingerprint profiles in a random amplified polymorphic DNA pattern analysis were isolated successively from five separate hospitals, suggesting the nosocomial spread of the organism in each hospital. In conclusion, many species of MBL-positive gram-negative rods are distributed widely in different hospitals in the Kinki region of Japan. The present findings should be considered during the development of policies and strategies to prevent the emergence and further spread of MBL-producing bacteria.
Nishio
Hisaaki
H
Clinical Laboratory, Shiga Medical Center for Adults, Moriyama, Shiga 524-8524, Japan. qq6w62t9@chive.ocn.ne.jp
Komatsu
Masaru
M
Shibata
Naohiro
N
Shimakawa
Kouichi
K
Sueyoshi
Noriyuki
N
Ura
Toshiro
T
Satoh
Kaori
K
Toyokawa
Masahiro
M
Nakamura
Tatsuya
T
Wada
Yasunao
Y
Orita
Tamaki
T
Kofuku
Tomomi
T
Yamasaki
Katsutoshi
K
Sakamoto
Masako
M
Kinoshita
Shohiro
S
Aihara
Masanori
M
Arakawa
Yoshichika
Y
D000900:Anti-Bacterial Agents / Q000494:pharmacology; D006090:Gram-Negative Bacteria / Q000145:classification / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics; D006801:Humans; D007564:Japan; D007753:Laboratories; D007755:Laboratories, Hospital; D008826:Microbial Sensitivity Tests; D016133:Polymerase Chain Reaction; D011159:Population Surveillance; D019105:Random Amplified Polymorphic DNA Technique; D018440:beta-Lactam Resistance; D001618:beta-Lactamases / Q000378:metabolism*
D000900:Anti-Bacterial Agents; D001618:beta-Lactamases