Emergence of bacterial resistance in humans, animals and the environmentSunday, April 01, 2012, 12:30 - 13:30
A case of New Delhi metallo-beta-lactamase 1 in the Netherlands with secondary transmissionT. Halaby*, E.A. Reuland, N. al Naiemi, A. Potron, P.H.M. Savelkoul, C.M.J.E. Vandenbroucke-Grauls, P. Nordmann (Enschede, Amsterdam, NL; Le Kremlin BicÍtre, FR)
Objectives: Acquired carbapenemases such as New Delhi metallo-beta-lactamase 1 (NDM-1) are emerging resistance determinants in Gram-negative bacteria, leaving few or no therapeutic options. Here we describe a NDM-1 case in the Netherlands, imported from the Balkan area, and a secondary case in the same hospital.
Materials and methods: The study was performed as part of a retrospective analysis on a collection of 485 Enterobacteriaceae isolates, from patients in the east of the Netherlands. Antimicrobial susceptibility testing and species identification were performed by the VITEC 2. Cabapenems MIC values were determined by the E-test. Phenotypic ESBL confirmation was performed by a combination disc diffusion. For phenotypic confirmation of carbapenemase production, the modified Hodge test (MHT) and two inhibitor-based tests: ertapenem-boronic acid and imipenem-EDTA, were used. A microarray was used for genotypic characterisation of ESBLís and carbapenemases. Characterisation of NDM-gene and plasmid analysis, were done using PCR, sequencing and cloning. Genetic relatedness is tested by Amplified Fragment Length Polymorphism (AFLP). For genotyping the Multilocus sequence typing (MLST) was used.
Results: Two ESBL producing K.pneumoniae strains from two patients were selected for further analysis by their elevated MICís to meropenem. One patient was transferred from a hospital in Belgrado, Bosnia, to hospital in the east of the Netherlands on the 27th of August 2008 and directly placed in a separate room in isolation because of MRSA carriage. The second patient, with no travel history outside the Netherlands, was admitted to the same hospital between the 10th of Oktober and the 7th of November 2008. The results of antimicrobial susceptibility testing and phenotypic confirmations are shown in table 1. Molecular gene analysis revealed NDM-1, CTX-M-15, SHV-12,TEM-1, and OXA-1. Molecular plasmid analysis revealed the presence of a 70 kb, Inc II plasmid containing the bla NDM-1, and a 140 kb plasmid in both isolates. AFLP showed that both strains were identical. MLST analysis showed that both isolates belong to ST15.
Conclusions: This first encountered NDM-1 producing K. pneumoniae in the Netherlands underlines further that Balkan states constitute a secondary reservoir for NDM-1 producers. While cross transmission in Europe of NDM-1 producers has sporadically been reported, the index case was associated with a secondary case despite proactive measures aimed to control spread of resistant bacteria.