Objectives: The spread of carbapenem-resistant Enterobacteriaceae (CRE) represents one of the most worrisome problems for clinical medicine worldwide. In Italy, the Antibiotic-Resistance-Istituto Superiore di Sanità surveillance network, in collaboration with the Committee for Antimicrobial Agents of the Italian Society of Clinical Microbiologists, promoted a study to investigate the carbapenem-resistance mechanisms, clonal relatedness and capsular typing of a recent collection of carbapenem-resistant Klebsiella pneumoniae (CR-KP). Methods: A total of 17 laboratories distributed across Italy collected all consecutive non-replicate CR-KP isolated from invasive infections during two different study periods (2011-12 and 2013). Carbapenemase genes were searched for by filter hybridization and confirmed by PCR and sequencing. KPC-producing K. pneumoniae (KPC-KP) were typed by PFGE and MLST. Capsular types were identified by wzi gene typing. Results: Of the collected K. pneumoniae isolates (n=461), the overall proportion of CR-KP was 36.2% (n=167). The majority (97%) of the CR-KP were positive for the blaKPC gene. Among the KPC-KP population, nine different STs were detected with the majority of isolates (94%) belonging to the clonal group (CG) 258. A subpopulation that belonged to ST512 and showed an identical PFGE profile represented the majority (57%) of KPC-KP strains, with a countrywide distribution. Capsular characterization showed the predominance of the wzi154, cps-2 capsular type (88.8% of all CG258 strains). ST258 strains were associated with both cps-1 and cps-2 capsular types, while ST512 was associated with cps-2 only. Conclusions: Although a trend to a polyclonal evolution of the Italian KPC-KP was noted, this study showed that the KPC-KP population remained largely oligoclonal with the wide diffusion of an ST512 lineage carrying cps-2 capsular type and producing the KPC-3 enzyme.
Molecular epidemiology of KPC-producing Klebsiella pneumoniae from invasive infections in Italy: Increasing diversity with predominance of the ST512 clade II sublineage / Conte, V; Monaco, M; Giani, T; D'Ancona, F; Moro, Ml; Arena, F; D'Andrea, Mm; Rossolini, Gm; Pantosti, A; AR-ISS Study Group on Carbapenemase-Producing K., pneumoniae: Bianchi E; Catania, Mr; Cavalcanti, P; De Nittis, R; Dusi, Pa; Grandesso, S; Gualdi, P; Imbriani, A; Pini, B; Vincenzi, C; Meledandri, Alessio; Agrappi, C; Parisi, G; Pollini, S; Restelli, Ugo; Rocchetti, Romualdo; Vailati, F; Aschbacher, R; Barbaro, A; Bona, R; Chirillo, M; Corradini, S; Cuccurullo, S; De Bernochi, A; Dodi, C; Giammanco, Anna; Mencacci, A; Milano, F; Miragliotta, Giuseppe; Mungiguerra, M; Pedna, Mf; Piana, Daniela; Porcheddu, Gm; Rossi, Mr; Santino, I; Sartor, A; Sartore, P.. - In: JOURNAL OF ANTIMICROBIAL CHEMOTHERAPY. - ISSN 0305-7453. - 71:12(2016), pp. 1-6. [10.1093/jac/dkw337]
Molecular epidemiology of KPC-producing Klebsiella pneumoniae from invasive infections in Italy: Increasing diversity with predominance of the ST512 clade II sublineage
Catania MR;MELEDANDRI, ALESSIO;RESTELLI, UGO;ROCCHETTI, ROMUALDO;GIAMMANCO, ANNA;MIRAGLIOTTA, GIUSEPPE;Piana, Daniela;Sartor A;Sartore P.
2016
Abstract
Objectives: The spread of carbapenem-resistant Enterobacteriaceae (CRE) represents one of the most worrisome problems for clinical medicine worldwide. In Italy, the Antibiotic-Resistance-Istituto Superiore di Sanità surveillance network, in collaboration with the Committee for Antimicrobial Agents of the Italian Society of Clinical Microbiologists, promoted a study to investigate the carbapenem-resistance mechanisms, clonal relatedness and capsular typing of a recent collection of carbapenem-resistant Klebsiella pneumoniae (CR-KP). Methods: A total of 17 laboratories distributed across Italy collected all consecutive non-replicate CR-KP isolated from invasive infections during two different study periods (2011-12 and 2013). Carbapenemase genes were searched for by filter hybridization and confirmed by PCR and sequencing. KPC-producing K. pneumoniae (KPC-KP) were typed by PFGE and MLST. Capsular types were identified by wzi gene typing. Results: Of the collected K. pneumoniae isolates (n=461), the overall proportion of CR-KP was 36.2% (n=167). The majority (97%) of the CR-KP were positive for the blaKPC gene. Among the KPC-KP population, nine different STs were detected with the majority of isolates (94%) belonging to the clonal group (CG) 258. A subpopulation that belonged to ST512 and showed an identical PFGE profile represented the majority (57%) of KPC-KP strains, with a countrywide distribution. Capsular characterization showed the predominance of the wzi154, cps-2 capsular type (88.8% of all CG258 strains). ST258 strains were associated with both cps-1 and cps-2 capsular types, while ST512 was associated with cps-2 only. Conclusions: Although a trend to a polyclonal evolution of the Italian KPC-KP was noted, this study showed that the KPC-KP population remained largely oligoclonal with the wide diffusion of an ST512 lineage carrying cps-2 capsular type and producing the KPC-3 enzyme.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
