blaCTX-M-15 carried by IncF-type plasmids is the dominant ESBL gene in Escherichia coli and Klebsiella pneumoniae at a hospital in Ghana

Escherichia coli and Klebsiella pneumoniae producing extended-spectrum beta-lactamases (ESBLs) are among the most multidrug-resistant pathogens in hospitals and are spreading worldwide. Horizontal gene transfer and spread of high-risk clones are involved in ESBL dissemination. Investigation of the resistance phenotypes of 101 consecutive clinical E. coli (n = 58) and K. pneumoniae (n = 43) isolated at the Komfo Anokye Teaching Hospital in Ghana over 3 months revealed 63 (62%) with an ESBL phenotype. All 63 had a bla(CTX-M) gene, and sequence analysis showed that 62 of these were bla(CTX-M-15). bla(CTX-M-15) was linked to ISEcp1 and orf477 Delta. in all isolates, and most isolates also carried bla(TEM), aac(3)-II, aacA4cr, and/or bla(OXA-30) genes on IncF plasmids. XbaI/pulsed-field electrophoresis showed heterogeneity among isolates of both species, suggesting that bla(CTX-M-15) dissemination is caused by horizontal gene transfer rather than clonal spread of these species in Ghana. Crown Copyright (C) 2016 Published by Elsevier Inc. All rights reserved.