Emergence of clonally related Klebsiella pneumoniae isolates of sequence type 258 producing KPC-2 carbapenemase in Belgium

Abstract

Sir, The Klebsiella pneumoniae carbapenemase (KPC) is a class A b-lactamase that confers resistance to virtually all b-lactams including carbapenems. Initially reported in the USA in a Klebsiella isolate in 1996, KPC-producing K. pneumoniae have been responsible for large nosocomial outbreaks in the USA, Israel and Greece where these isolates are now endemic in hospitals. The rapid dissemination of KPC enzymes among and across different enterobacterial species is likely to be due to the localization of blaKPC genes on transferable broad host range plasmids and their association with a transposon, but is also linked with a disseminated international clone of KPC-producing K. pneumoniae isolates of sequence type (ST) 258. Here we report on the first three cases of KPC-2-producing ST258 K. pneumoniae that were detected in Belgium, subsequent to the transfer of patients from three Greek hospitals. In 2009, a patient with high-grade bladder neoplasm with pelvic metastases was transferred from a hospital in Greece to St-Pierre University Hospital in Brussels. Six weeks later, a patient with severe trauma was transferred from another hospital in the same region of Greece to the intensive care unit (ICU) of the same Brussels hospital. Finally, a few days later, the third polytrauma patient was transferred from the ICU of a hospital in Rhodes to the ICU of Erasme University Hospital in Brussels. Upon admission, a urine culture for the first patient and rectal swabs from the two other patients revealed the presence of multidrug-resistant K. pneumoniae (isolates Hk1, Hk2 and Rh1, respectively) with reduced susceptibility to carbapenems. No secondary local transmission occurred in the two hospitals following the rapid implementation of strict infection control measures. MICs produced using the Vitek2 system (N046 AST cards) and Etest (AB BIODISK, Solna, Sweden) were interpreted according to clinical breakpoints from the European Committee for Antimicrobial Susceptibility Testing (EUCAST). The three multidrug-resistant isolates showed high-level resistance to all penicillins (including temocillin) and to all expanded-spectrum cephalosporins except cefepime to which they all remained borderline susceptible (MICs of 8–16 mg/L) (Table 1). Interestingly, the three isolates appeared to be of intermediate susceptibility to meropenem using the Vitek2 system (MIC of 4–8 mg/L) while they were resistant to meropenem by Etest (MIC of 32 mg/L). All the isolates remained susceptible to gentamicin but were of intermediate