Genomic characterization of multidrug-resistant ESBL-producing Klebsiella pneumoniae isolated from a Ghanaian teaching hospital

Objectives: This study delineated the clonal lineages, antibiotic resistome and plasmid replicon types in multidrug-resistant K. pneumoniae isolates from a teaching hospital in Ghana. Methods: Identification and antibiotic susceptibility testing were done using the MALDI-TOF MS and Vitek-2 automated system. Genomic DNA extraction was carried out using the NucliSens easyMAG (R) (BioMerieux) kits and the DNA was subjected to whole genome sequencing (WGS) using the Illumina MiSeq platform. Results: Of the 200 isolates obtained, 37 were identified as K. pneumoniae of which 9 were resistant to all second and third-generation cephalosporins. These 9 isolates selected for further genomic analysis were characterized by the presence of 8 diverse sequence types (STs), capsular polysaccharide serotypes (K types and wzi allelic types) and multiple genes encoding resistance to beta-lactams (bla(CTX-M-15), bla(SHV-11), bla(TEM-1B), bla(OXA-1) ), aminoglycosides (aac(3)-IIa, strB, strA, aadA16), fluoroquinolones/quinolones (qnrB66, oqxA, oqxB) and other antibiotic classes. Resistance genes were associated with plasmids, predominantly IncFIB(K) and ColRNAI. Multiple and diverse mutations in quinolone resistance-determining regions of gyrA (S83Y, D87A) and parC (S80I, N304S) in isolates resistant to ciprofloxacin (MIC > 4 mg/mL) were found. Global phylogenomic analysis affirmed the diverse clonal clustering and origin of these isolates. Conclusions: The varied clonal clusters and resistome identified in the multidrug-resistant K. pneumoniae isolates is a major threat to the management of infections in Ghana. The molecular characterization of antibiotic resistance is thus imperative to inform strategies for containment. (C) 2019 The Authors. Published by Elsevier Ltd on behalf of International Society for Infectious Diseases.