out: first, these strains were not detected in Bariloche until 2010
and, second, they harboured blaKPC-2in the Variant 1a.6ST162
was isolated from a patient with no recent history of travel.
Interestingly, this patient shared the same ward simultaneously
KPC-producing Enterobacter cloacae and K. pneumoniae. In
these isolates, the blaKPC-2genetic environment matched that
of ST162. However, blaKPC-2 in E. cloacae and K. pneumoniae
was associated with plasmids of different sizes (40 and
.150 kb, respectively) and different Inc groups (N and FIIS,
respectively)6from that detected in ST162. Thus, we speculated
that the surge of ST162 could be due to blaKPC-2mobilization
among different plasmids (i.e. transposition).
Clonal complexes CC111 and CC235 have been reported as
the major clones involved in the global dissemination of
extended-spectrum and metallo-b-lactamases in P. aeruginosa.8
However, we observed that the main dissemination of KPC was
mediated by a new clone (ST654) not related to both CC111
and CC235. ST654 is endemic in Singapore,9where it has been
associated with IMP-1 and IMP-26; it has also been reported in
Sweden as a VIM-2 producer, although the isolate was imported
from Tunisia.10Unlike other Latin American regions, such as
Puerto Rico and Colombia, where different PFGE types and STs
have been identified,1,4the dissemination of KPC-producing
P. aeruginosa in Argentina is mainly associated with a
single clone. These findings confirm that ST654 plays an
important role in the global spread of carbapenemases, either
metallo-b-lactamases or KPC. Thus, the worldwide dissem-
ination of KPC-producing P. aeruginosa of ST654 might be
expected and should be monitored.
Part of this work was presented at the Fifty-first Interscience Conference
on Antimicrobial Agents and Chemotherapy, Chicago, IL, 2011 (Abstract
Pseudomonas aeruginosa KPC Group
Sanatorio San Carlos, Bariloche, Rı ´o Negro, Argentina: Barbara Bavdaz;
Hospital Privado Regional del Sur y Sanatorio del Sol, Bariloche, Rı ´o
Negro, Argentina: Gabriela Rubinstein; Hospital Zonal de Bariloche,
Bariloche, Rı ´o Negro, Argentina: Nestor Blazquez; Hospital Zonal de
Lago Puelo: Pablo Nouveau; Laboratorio Roca, Clı ´nica Roca, General
Roca, Rio Negro, Argentina: Silvana Cecchi; Hospital Zonal de Esquel,
Chubut, Argentina: Omar Daher; Hospital Privado Centro Modelo de
Co ´rdoba, Co ´rdoba: Mario Vilaro ´; Hospital Municipal de Gastroenterologı ´a
‘B. Udaondo’, Ciudad Auto ´noma de Buenos Aires, Argentina: Claudia
Brotto; and Hospital Julio Perrando, Resistencia, Chaco, Argentina:
This work was supported by the regular federal budget of the Ministry of
Health of Argentina.
None to declare.
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J Antimicrob Chemother 2012
Advance Access publication 18 January 2012
In vitro activity of tigecycline against
blood culture isolates from critically
Soham Gupta, Chowdappa Aruna, Savitha Nagaraj,
Mary Dias and Sethumadhavan Muralidharan*
Department of Microbiology, St John’s Medical College and
Hospital, Bangalore-560034, India
*Corresponding author. Tel: +91-80-22065052; Email: dr.murali.2009@
Keywords: MIC, VITEK 2C, intensive care unit
With increasing resistance to currently available antibiotics
and decreasingnumbersofnewerantimicrobialagents, tigecycline
by guest on January 23, 2016