Molecular characterization of extended-spectrum beta-lactamases produced by nosocomial isolates of Enterobacteriaceae from an Italian nationwide survey.
Extended-spectrum beta-lactamases (ESBLs) are widespread in hospital settings worldwide. The present investigation was undertaken to assess the distribution and prevalence of ESBLs belonging to the TEM and SHV families in 448 ESBL-producing clinical isolates of Enterobacteriaceae collected from 10 different Italian hospitals. The natures of TEM and SHV determinants were identified by direct sequencing of PCR-amplified genes. TEM-52 and SHV-12 were the most common variants, and they were found in most hospitals and in several different species. Other less frequent variants included TEM-5, TEM-12, TEM-15, TEM-19, TEM-20, TEM-24, TEM-26, TEM-43, TEM-60, TEM-72, TEM-87, SHV-2a, SHV-5, and SHV-11. Proteus mirabilis was the most common producer of TEM-type ESBLs, while Klebsiella pneumoniae was the most common producer of SHV-type ESBLs. The distribution of TEM- and SHV-type ESBL variants in Enterobacteriaceae from Italian hospitals exhibited notable differences from those from other geographical settings.
Perilli
Mariagrazia
M
Dipartimento di Scienze e Tecnologie Biomediche, Università di L'Aquila, L'Aquila, Italy.
Dell'Amico
Emanuela
E
Segatore
Bernardetta
B
de Massis
Maria Rosaria
MR
Bianchi
Ciro
C
Luzzaro
Francesco
F
Rossolini
Gian Maria
GM
Toniolo
Antonio
A
Nicoletti
Giuseppe
G
Amicosante
Gianfranco
G
D003428:Cross Infection / Q000453:epidemiology / Q000382:microbiology*; D004755:Enterobacteriaceae / Q000201:enzymology* / Q000235:genetics; D004756:Enterobacteriaceae Infections / Q000453:epidemiology / Q000382:microbiology*; D006761:Hospitals; D006801:Humans; D007558:Italy / Q000453:epidemiology; D001618:beta-Lactamases / Q000096:biosynthesis* / Q000145:classification / Q000235:genetics*
D001618:beta-Lactamases