The emergence of carbapenem-resistant Klebsiella pneumoniae (CR-KP) has become a significant problem worldwide and also being a major threat ...SkiptomaincontentAdvertisementSearchallBMCarticlesSearchDownloadPDFResearcharticleOpenAccessPublished:14November2018CharacteristicsofNDM-1-producingKlebsiellapneumoniaeST234andST1412isolatesspreadinaneonatalunitXuHuang1,2 na1,XiangjunCheng1,2 na1,PengfeiSun1,2,ChenjieTang1,2,FangNi1,2&GenyanLiu ORCID:orcid.org/0000-0002-1004-25171,2 BMCMicrobiologyvolume 18,Article number: 186(2018)Citethisarticle1944Accesses8Citations1AltmetricMetricsdetailsAbstractBackgroundTheemergenceofcarbapenem-resistantKlebsiellapneumoniae(CR-KP)hasbecomeasignificantproblemworldwideandalsobeingamajorthreattochildrenandnewborns.HerewereportanoutbreakofNDM-1-producingK.pneumoniaeinaneonatalunit.ResultsSixCR-KPstrains,isolatedfromneonateswithsymptomsofinfection,wereidentifiedusingaVITEK-2compactsystem,andtheclinicaldatawereretrievedfromtheelectroniccaserecords.InvitrosusceptibilitytestingwithbrothdilutionmethodshowedthatallsixK.pneumoniaeisolateswereresistanttocarbapenemsandsusceptibletocolistin,aminoglycosides,fluoroquinolonesandtigecycline.Basedonthepolymerasechainreactionresults,eachisolatewasfoundtobeblaNDM-1genepositive.Clonalrelationshipswereanalysedusingpulsed-fieldgelelectrophoresis(PFGE)andmultilocussequencetyping(MLST)andshowedthattwodifferentPFGEpatternswereformed,whichbelongedtosequencetypesST234andST1412.PlasmidscarryingblaNDM-1weresuccessfullytransferredfromfourofthesixisolatestoanEscherichiacolirecipientthroughconjugativeassays.S1-PFGEandSouthernblothybridizationshowedthatfourNDM-1-producingK.pneumoniaewereclonalandcarriedblaNDM-1onthesameplasmid.Theoutbreakwaseffectivelycontrolledbyreducingthepotentialinfectionsources.Allthepatientsweresuccessfullytreatedandrecoveredafterreceivinganincreaseddoseofcarbapenems.Althoughthesourceofthisoutbreakwasnotclear,comprehensivemeasureswerecarriedoutandtheoutbreakwaseffectivelycontrolled.ConclusionsST23