TY - JOUR
T1 - Multiple CTX-M-type extended-spectrum β-lactamases in nosocomial isolates of Enterobacteriaceae from a hospital in Northern Italy
AU - Pagani, Laura
AU - Dell'Amico, Emanuela
AU - Migliavacca, Roberta
AU - D'Andrea, Marco Maria
AU - Giacobone, Ernesto
AU - Amicosante, Gianfranco
AU - Romero, Egidio
AU - Rossolini, Gian Maria
PY - 2003/9/1
Y1 - 2003/9/1
N2 - Twelve isolates of Enterobacteriaceae (1 of Klebsiella pneumoniae, 8 of Escherichia coli, 1 of Proteus mirabilis, and 2 of Proteus vulgaris) classified as extended-spectrum β-lactamase (ESBL) producers according to the ESBL screen flow application of the BD-Phoenix automatic system and for which the cefotaxime MICs were higher than those of ceftazidime were collected between January 2001 and July 2002 at the Laboratory of Clinical Microbiology of the San Matteo University Hospital of Pavia (northern Italy). By PCR and sequencing, a CTX-M-type determinant was detected in six isolates, including three of E. coli (carrying blaCTX-M1), two of P. vulgaris (carrying bla CTX-M-2), and one of K. pneumoniae (carrying blaCTX-M-15). The three CTX-M-1-producing E. coli isolates were from different wards, and genotyping by pulsed-field gel electrophoresis (PFGE) revealed that they were clonally unrelated to each other. The two CTX-M-2- producing P. vulgaris isolates were from the same ward (although isolated several months apart), and PFGE analysis revealed probable clonal relatedness. The blaCTX-M-1 and blaCTX-M-2 determinants were transferable to E. coli by conjugation, while conjugative transfer of the blaCTX-M-15 determinant from K. pneumoniae was not detectable. Present findings indicate that CTX-M enzymes of various types are present also in Italy and underscore that different CTX-M determinants can be found in a single hospital and can show different dissemination patterns. This is also the first report of CTX-M-2 in P. vulgaris.
AB - Twelve isolates of Enterobacteriaceae (1 of Klebsiella pneumoniae, 8 of Escherichia coli, 1 of Proteus mirabilis, and 2 of Proteus vulgaris) classified as extended-spectrum β-lactamase (ESBL) producers according to the ESBL screen flow application of the BD-Phoenix automatic system and for which the cefotaxime MICs were higher than those of ceftazidime were collected between January 2001 and July 2002 at the Laboratory of Clinical Microbiology of the San Matteo University Hospital of Pavia (northern Italy). By PCR and sequencing, a CTX-M-type determinant was detected in six isolates, including three of E. coli (carrying blaCTX-M1), two of P. vulgaris (carrying bla CTX-M-2), and one of K. pneumoniae (carrying blaCTX-M-15). The three CTX-M-1-producing E. coli isolates were from different wards, and genotyping by pulsed-field gel electrophoresis (PFGE) revealed that they were clonally unrelated to each other. The two CTX-M-2- producing P. vulgaris isolates were from the same ward (although isolated several months apart), and PFGE analysis revealed probable clonal relatedness. The blaCTX-M-1 and blaCTX-M-2 determinants were transferable to E. coli by conjugation, while conjugative transfer of the blaCTX-M-15 determinant from K. pneumoniae was not detectable. Present findings indicate that CTX-M enzymes of various types are present also in Italy and underscore that different CTX-M determinants can be found in a single hospital and can show different dissemination patterns. This is also the first report of CTX-M-2 in P. vulgaris.
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U2 - 10.1128/JCM.41.9.4264-4269.2003
DO - 10.1128/JCM.41.9.4264-4269.2003
M3 - Article
C2 - 12958255
AN - SCOPUS:0041919382
VL - 41
SP - 4264
EP - 4269
JO - Journal of Clinical Microbiology
JF - Journal of Clinical Microbiology
SN - 0095-1137
IS - 9
ER -