Outbreak of plasmid-mediated NDM-1-producing Klebsiella pneumoniae ST105 among neonatal patients in Yunnan, China

Abstract

BackgroundIn the past decade, the carbapenemase-producing Enterobacteriaceae (CPE) have been reported worldwide. Emergence of carbapenemase-producing strains among Enterobacteriaceae has been a challenge for treatment of clinical infection. The present study was undertaken to investigate the characteristics of carbapenem-resistant Klebsiella pneumoniae recovered from an outbreak that affected 17 neonatal patients in neonatal intensive care unit (NICU) of Kunming City Maternal and Child health Hospital, which is located in the Kunming city in far southwest of China.MethodsMinimum inhibitory concentrations (MICs) for antimicrobial agents were determined according to the guidelines of the Clinical and Laboratory Standards Institute (CLSI); Modified Hodge test and Carba-NP test were preformed to identified the phenotypes of carbapenemases producing; To determine whether carbapenem resistance was transferable, a conjugation experiment was carried out in mixed broth cultures; Resistant genes were detected by using PCR and sequencing; Plasmids were typed by PCR-based replicon typing method; Clone relationships were analyzed by using multilocus-sequence typing (MLST) and pulsed field gel electrophoresis (PFGE).ResultsEighteen highly carbapenem-resistant Klebsiella pneumoniae were isolated from patients in NICU and one carbapenem-resistant K. pneumoniae isolate was detected in incubator water. All these isolates harbored blaNDM-1. Moreover, other resistance genes, viz., blaIMP-4, blaSHV-1, blaTEM-1, blaCTX-M-15, qnrS1, qnrB4, and aacA4 were detected. The blaNDM-1 gene was located on a ca. 50 kb IncFI type plasmid. PFGE analysis showed that NDM-1-producing K. pneumoniae were clonally related and MLST assigned them to sequence type 105.ConclusionsNDM-1 producing strains present in the hospital environment pose a potential risk and the incubator water may act as a diffusion reservoir of NDM-1- producing bacteria. Nosocomial surveillance system should play a more important role in the infection control to limit the spread of these pathogens.

Plasmid evolution in carbapenemase‐producing Enterobacteriaceae: a review

“…Other plasmid replicon groups, including IncF, IncR, IncCol, L/M, and A/C, have also been described in NDM‐producing K. pneumoniae in Australia, China, Mexico, and Vietnam (Fig. ) . Furthermore, other Klebsiella spp., such as K. oxytoca , do not have a wide distribution of replicon groups, as only the IncN and IncF groups have been described in them in few countries (Table ).…”

“…These narrow‐host range (IncF) plasmids are not only responsible for disseminating KPC, but also NDM in E. coli and K. pneumoniae . Multiple plasmids have been reported, since 2012 and until recently, to carry NDM variants, particularly on IncFIB and IncFII plasmid types in K. pneumoniae and E. coli , respectively (Table and Fig.…”

“…Two major carbapenemases, bla IMP and bla NDM , are predominantly detected in these species, with IncHI2, A/C, IncP, and IncX3 being the plasmid types responsible for their dissemination between species . The isolates in these reports were recovered from both clinical and environmental samples, including river water and domestic cats in Angola, Australia, Canada, China, India, Spain, and the United States (Table ) . Citrobacter spp.…”

The rapid spread of carbapenem-resistant Enterobacteriaceae

“…Co-presence of ESBLs and NDM in the same isolate was high (78.5%, 106/135), but dual carbapenemase prevalence was fortunately low (1/135 with bla VIM-1 + bla NDM , 2/135 with bla OXA-181 + bla NDM ) [Biedenbach 2015]. A nosocomial outbreak declared in March 2014 of 19 K. pneumoniae ST10 in the neonatal intensive care unit of a Chinese hospital found that all isolates harbored bla NDM-1 on conjugative IncFI plasmids and that co-production of bla IMP-4 was common (36.8%, 7/19) but fortunately so was tigecycline, amikacin, and ciprofloxacin susceptibility [Zheng 2016]. K. pneumoniae was overwhelmingly responsible for NDM production in CRE colonized patients (370/374 patients) from Poland, a non-endemic area, during a 2012–2014 outbreak [Baraniak 2016].…”

An Uncommon ST1224 NDM-1-Producing <b><i>Klebsiella pneumoniae</i></b> Isolated from the Bloodstream of a Leukemia Patient in China

“…NDM-1, a carbapenemase, was first detected in Sweden in a patient previously hospitalized in India [2]. Since then, NDM-1-positive K. pneumoniae strains have been sequentially reported in many other countries [3,4] - a reminder that the dissemination of NDM-1-producing K. pneumoniae could spread throughout the world. NDM-1 can hydrolyze all β-lactam antibiotics except aztreonam; furthermore, it cannot be inhibited by β-lactam inhibitors [5].…”