1 www.eurosurveillance.org Rapid communications Emergence of four cases of KPC-2 and KPC-3-carrying Klebsiella pneumoniae introduced to Switzerland, 2009–10 B Babouee 1 , A F Widmer 1 , O Dubuis 2 , D Ciardo 2 , S Droz 3 , B Y Betsch 4 , C Garzoni 4 , U Führer 4 , M Battegay 1 , R Frei 5 , D Goldenberger (dgoldenberger@uhbs.ch) 5 1. Division of Infectious Diseases and Hospital Epidemiology, University Hospital Basel, Basel, Switzerland 2. Viollier AG, Basel, Switzerland 3. Institute for Infectious Diseases, University of Berne, Berne, Switzerland 4. University Clinic for Infectious Diseases, University Hospital and University of Berne, Inselspital, Berne, Switzerland 5. Division of Clinical Microbiology, University Hospital Basel, Basel, Switzerland Citation style for this article: Babouee B, Widmer AF, Dubuis O, Ciardo D, Droz S, Betsch BY, Garzoni C, Führer U, Battegay M, Frei R, Goldenberger D. Emergence of four cases of KPC-2 and KPC- 3-carrying Klebsiella pneumoniae introduced to Switzerland, 2009–10. Euro Surveill. 2011;16(11):pii=19817. Available online: http://www.eurosurveillance.org/ ViewArticle.aspx?ArticleId=19817 Article published on 17 March 2011 We report four epidemiologically unrelated cases of KPC-carrying Klebsiella pneumoniae identified in Switzerland between May 2009 and November 2010. Three cases were transferred from Italy (two KPC-3, one KPC-2) and one from Greece (KPC-2). Resistance to colistin and doxycycline emerged in one KPC-3– carrying K. pneumoniae strain during therapy. These results demonstrate ongoing dissemination of KPC throughout Europe. Rapid and reliable identification of KPC and implementation of control measures is essen- tial to limit spread. Introduction Carbapenems are first-line drugs for severe infections caused by Enterobacteriaceae expressing extended- spectrum beta-lactamases (ESBLs). The emergence of carbapenemase-producing Enterobacteriaceae in the past years is of great concern [1]. After the char- acterisation of the first Klebsiella pneumoniae isolate producing carbapenemase of the KPC type in 1996 in the United States [2], the KPC-producing bacteria spread worldwide. Poirel et al. reported the first KPC-2 K. pneumoniae isolate in Switzerland imported from Sicily (Italy) in 2010 [3]. Here, we report four addi- tional imported cases of KPC-carrying K. pneumoniae detected in Switzerland. Materials and methods The four KPC-suspected strains were collected from dif- ferent Swiss hospitals and were sent to our laboratory in Basel for confirmation. We performed conventional susceptibility testing using an automated micro-dilu- tion test system (Micronaut-S, MERLIN Diagnostika mbH).Determination of minimum inhibitory con- centrations (MIC) was performed with Etest stripes (bioMérieux). Results were interpreted according to the European Committee on Antimicrobial Susceptibility Testing (EUCAST) guidelines [4], except for doxycycline which was interpreted according to the guidelines of Clinical and Laboratory Standards Institute (CLSI) [5]. For phenotypic identification of KPC-producing iso- lates, both double disc synergy test and modified Hodge test were applied [1] . KPC-specific PCR and direct sequencing of the region encompassing the main part of the bla KPC gene (ca. 820 nucleotides, sequenced in both directions) was performed accord- ing to Bradford et al. [6]. The KPC type was identified by the BLAST programme from the National Center for Biotechnology Information Web site (http://www.ncbi. nlm.nih.gov/BLAST). Clinical data were available for two patients and were collected by full chart review. Results Four cases of KPC-carrying K. pneumoniae were detected in Switzerland between May 2009 and November 2010, two of type KPC-2 and two of type KPC-3. All patients were between 50 and 70 years-old and had been transferred from abroad, three from Italy and one from Greece. Two patients were colonised and two were infected with KPC-producing K. pneumoniae (Table 1). The antimicrobial susceptibility profiles of the four K. pneumoniae isolates are listed in Table 2. Double disc synergy test as well as the modified Hodge test showed positive results for KPC-production in all four cases. Case 1 The patient in their 50s lived in Greece and travelled to Switzerland in September 2009. The person was colonised in the urine, inguinal and perineum with