Genomic background of the Klebsiella pneumoniae NDM-1 outbreak in Poland, 2012-18

OBJECTIVES

To characterize genomes of Klebsiella pneumoniae ST11 NDM-1 responsible for a countrywide outbreak in Poland and compare them phylogenetically with other Polish and international ST11 strains.

METHODS

Seventy-one carbapenemase-producing K. pneumoniae ST11 isolates from Poland, including 66 representatives of the NDM-1 epidemic from 2012-18, were sequenced using Illumina MiSeq. Additionally, three outbreak isolates were also sequenced using MinION. The clonality and phylogenetic analysis was done by core-genome MLST and SNP approaches. Resistomes, virulomes, K/O antigens and plasmid replicons were screened for. The detailed plasmid analysis was based on full assemblies using Oxford Nanopore Technologies data.

RESULTS

Chromosomes of the outbreak isolates formed an essentially homogeneous cluster (though accumulating SNPs gradually with time), differing remarkably from other Polish NDM-1/-5-, KPC-2- or OXA-48-producing K. pneumoniae ST11 strains. The cluster belonged to a clade with 72 additional isolates identified worldwide, including closely related NDM-1 producers from several countries, including organisms from Bulgaria and Greece. All these had KL24 and O2v1 antigens and the chromosomal yersiniabactin locus YbST230 residing in the ICEKp11 element. The specific blaNDM-1-carrying Tn125 transposon derivative, named Tn125A, was located in IncFII/pKPX-1- and/or IncR-like plasmids; however, the IncRs rearranged extensively during the outbreak, contributing to highly dynamic plasmid profiles and resistomes.

CONCLUSIONS

The K. pneumoniae ST11 NDM-1 genotype that has been expanding in Poland since 2012 is largely monoclonal and represents a novel international high-risk lineage that is also spreading in other countries.

[Clinical value of ultrasonographic assessment of fetal hypotrophy and the effects of its treatment]

The clinical usefulness was assessed of ultrasonography in the study of fetal hypotrophism determining the parameters BIP, THQ and placental parameters. Fetal growth was assessed and in case of hypotrophism adequate therapeutic management was undertaken. The study was carried out on 56 pregnant women referred for diagnosis and treatment of fetal hypotrophism in the period 1983-1985. The control group comprised 56 women with physiological pregnancy. The study was carried out with examinations at weekly intervals from the 24th week of pregnancy till labour using a Hellige-Panavista unit with a 2.5 MHz probe. The BIP and THQ dimensions were calculated a together with placental parameters. The oestriol level was determined in 24-hour urine. The underlying disease and fetal hypotrophism were treated. The most valuable indicator for the determination of asymmetrical and symmetrical type of hypotrophism and for its monitoring was the BIP/THQ index. Ultrasonography makes possible a rapid and accurate diagnosis of fetal condition and control of its treatment. Ultrasonographic observation of the placenta is a source of valuable information for the obstetrician. Oestriol determination is without any greater significance for monitoring of fetal hypotrophism.