Multi-hospital occurrence of pan-resistant Klebsiella pneumoniae ST147 with an ISEcp1-directed blaOXA-181 insertion into the mgrB gene in the United Arab Emirates [PublishAheadOfPrint]

The emergence of pan-resistant Klebsiella pneumoniae strains is an increasing concern. In the current study we describe a cluster of 9 pan-resistant K. pneumoniae ST147 isolates encountered in 4 patients over nearly one year in 3 hospitals of the United Arab Emirates. The isolates exhibited highly similar genotypes. All produced chromosomally encoded OXA-181 and the majority also produced the NDM-5 carbapenemase. Similarly to the previously described single isolate from the UAE, MS6671, the mgrB was disrupted by a functional, ISEcp1-driven bla_OXA-181 insertion causing resistance to carbapenems. The mutation was successfully complemented with an intact mgrB gene indicating that it was responsible for colistin resistance. bla_NDM-5 was located within a resistance island of an approximately 100 kb IncFII plasmid carrying ermB, mph(A), bla_TEM-1B, rmtB, bla_NDM-5, sul1, aadA2 and dfrA12 resistance genes. Sequencing this plasmid (pABC143-NDM) revealed that its backbone was nearly identical to that of plasmid pMS6671E from which several resistance genes, including bla_NDM-5, had been deleted. More extensive similarities of the backbone and the resistance island were found between pABC143C-NDM and the bla_NDM-5 carrying IncFII plasmids of two K. pneumoniae ST147 isolates from South Korea, one of which was colistin resistant, and both also produced OXA-181. Notably one of these strains was isolated from a patient transferred from the UAE. Our data show that this pan-resistant clone has an alarming capacity to maintain itself over an extended period of time, and even likely to be transmitted internationally.

http://ift.tt/2oFh9zj