title: Diffusion and transmission of carbapenem-resistant Klebsiella pneumoniae in the medical and surgical wards of a university hospital in Milan, Italy.
abstract: Carbapenem-resistant Klebsiella pneumoniae (CRKP) is emerging as a public health problem worldwide. In Italy, a remarkable increase in CRKP cases has been reported since 2010. In this study, CRKP diffusion, distribution and in-hospital transmission trends were evaluated in a university hospital in Milan, Italy, from January 2012 to December 2013. Isolates from 63 newly detected CRKP-positive patients were genotyped, and possible transmission was determined by combining the molecular results with data concerning the patients' admission and in-hospital transfers. Most of the cases (90.4%) were from general medical and surgery wards, and the remaining 9.6% were from the intensive care unit. Fifteen of the 46 hospital-associated cases (32.6%) were attributable to in-hospital transmission. After the introduction of targeted and hospital-wide control measures, the transmission index significantly decreased from 0.65 to 0.13 (p=0.01). There was also a decrease in the overall nosocomial case incidence, from 0.37 to 0.17 per 1000 person-days (p=0.07). Our findings indicate that the spread of CRKP in Northern Italy hospitals may go far beyond high-risk settings (i.e., intensive care units) and that strict surveillance should be extended to general areas of care.
authors.affiliation: Direzione Medica di Presidio, Azienda Ospedaliera-Polo Universitario Luigi Sacco, Via G.B. Grassi 74, 20156 Milano, Italy; Sezione di Malattie Infettive e Immunopatologia, Dipartimento di Scienze Cliniche, Ospedale Luigi Sacco, Università degli Studi di Milano, Via G.B. Grassi 74, 20156 Milano, Italy. Electronic address: annalisa.ridolfo@unimi.it.
authors.forename: Anna L
authors.initials: AL
authors.lastname: Ridolfo
authors.affiliation: Laboratorio di Microbiologia Clinica, Virologia e Diagnostica Bioemergenze, Ospedale Luigi Sacco, Università degli Studi di Milano, Via G.B. Grassi 74, 20156 Milano, Italy.
authors.forename: Sara G
authors.initials: SG
authors.lastname: Rimoldi
authors.affiliation: Laboratorio di Microbiologia Clinica, Virologia e Diagnostica Bioemergenze, Ospedale Luigi Sacco, Università degli Studi di Milano, Via G.B. Grassi 74, 20156 Milano, Italy.
authors.forename: Cristina
authors.initials: C
authors.lastname: Pagani
authors.affiliation: Direzione Medica di Presidio, Azienda Ospedaliera-Polo Universitario Luigi Sacco, Via G.B. Grassi 74, 20156 Milano, Italy.
authors.forename: Andrea F
authors.initials: AF
authors.lastname: Marino
authors.affiliation: Direzione Medica di Presidio, Azienda Ospedaliera-Polo Universitario Luigi Sacco, Via G.B. Grassi 74, 20156 Milano, Italy.
authors.forename: Anna
authors.initials: A
authors.lastname: Piol
authors.affiliation: Direzione Medica di Presidio, Azienda Ospedaliera-Polo Universitario Luigi Sacco, Via G.B. Grassi 74, 20156 Milano, Italy.
authors.forename: Matteo
authors.initials: M
authors.lastname: Rimoldi
authors.affiliation: Direzione Medica di Presidio, Azienda Ospedaliera-Polo Universitario Luigi Sacco, Via G.B. Grassi 74, 20156 Milano, Italy.
authors.forename: Pietro
authors.initials: P
authors.lastname: Olivieri
authors.affiliation: Sezione di Malattie Infettive e Immunopatologia, Dipartimento di Scienze Cliniche, Ospedale Luigi Sacco, Università degli Studi di Milano, Via G.B. Grassi 74, 20156 Milano, Italy.
authors.forename: Massimo
authors.initials: M
authors.lastname: Galli
authors.affiliation: Direzione Medica di Presidio, Azienda Ospedaliera-Polo Universitario Luigi Sacco, Via G.B. Grassi 74, 20156 Milano, Italy.
authors.forename: Lucia
authors.initials: L
authors.lastname: Dolcetti
authors.affiliation: Laboratorio di Microbiologia Clinica, Virologia e Diagnostica Bioemergenze, Ospedale Luigi Sacco, Università degli Studi di Milano, Via G.B. Grassi 74, 20156 Milano, Italy.
authors.forename: Maria R
authors.initials: MR
authors.lastname: Gismondo
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D015780:Carbapenems / Q000494:pharmacology*; D003428:Cross Infection / Q000382:microbiology* / Q000635:transmission; D024881:Drug Resistance, Bacterial; D005260:Female; D005838:Genotype; D006785:Hospitals, University; D006801:Humans; D007558:Italy / Q000453:epidemiology; D007710:Klebsiella Infections / Q000453:epidemiology / Q000382:microbiology* / Q000635:transmission; D007711:Klebsiella pneumoniae / Q000187:drug effects* / Q000235:genetics; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D055815:Young Adult
chemical_list: D000900:Anti-Bacterial Agents; D015780:Carbapenems
keywords: Active screening; Active surveillance; Carbapenem-resistant Klebsiella pneumoniae; Cross-transmission; Infections control measures; Multidrug-resistant agents