Dissemination of IncF-type plasmids in multiresistant CTX-M-15-producing Enterobacteriaceae isolates from surgical-site infections in Bangui, Central African Republic

Abstract

BackgroundSurgical-site infection is the most frequent health care-associated infection in the developing world, with a strikingly higher prevalence than in developed countries We studied the prevalence of resistance to antibiotics in Enterobacteriaceae isolates from surgical-site infections collected in three major tertiary care centres in Bangui, Central African Republic. We also studied the genetic basis for antibiotic resistance and the genetic background of third-generation cephalosporin-resistant (3GC-R) Enterobacteriaceae.ResultsBetween April 2011 and April 2012, 195 patients with nosocomial surgical-site infections were consecutively recruited into the study at five surgical departments in three major tertiary care centres. Of the 165 bacterial isolates collected, most were Enterobacteriaceae (102/165, 61.8%). Of these, 65/102 (63.7%) were 3GC-R, which were characterized for resistance gene determinants and genetic background. The blaCTX-M-15 and aac(6′)-Ib-cr genes were detected in all strains, usually associated with qnr genes (98.5%). Escherichia coli, the most commonly recovered species (33/65, 50.8%), occurred in six different sequence types, including the pandemic B2-O25b-ST131 group (12/33, 36.4%). Resistance transfer was studied in one representative strain of the resistance gene content in each repetitive extragenic palindromic and enterobacterial repetitive intergenic consensus sequence-PCR banding pattern. Plasmids were characterized by PCR-based replicon typing and sub-typing schemes. In most isolates (18/27, 66.7%), blaCTX-M-15 genes were found in incompatibility groups F/F31:A4:B1 and F/F36:A4:B1 conjugative plasmids. Horizontal transfer of both plasmids is probably an important mechanism for the spread of blaCTX-M-15 among Enterobacteriaceae species and hospitals. The presence of sets of antibiotic resistance genes in these two plasmids indicates their capacity for gene rearrangement and their evolution into new variants.ConclusionsDiverse modes are involved in transmission of resistance, plasmid dissemination probably playing a major role.

Predominance of CTX-M-15 among ESBL Producers from Environment and Fish Gut from the Shores of Lake Victoria in Mwanza, Tanzania

“…As was already noted in studies from the Asian, European and the African continents which documented the emergence and spread of bla CTX-M-15 in humans and cattle (Madec et al, 2012; Zhang et al, 2013; Rafaï et al, 2015), CTX-M-15 was also found to be the predominant allele in this study. The gene was located on the chromosome or on different plasmids indicating extreme environmental mobility.…”

Detection of High Prevalence of TEM/SHV/CTX-M Genes in ESBL Producing and Multidrug Resistant Klebsiella Pneumoniae and Klebsiella Oxytoca

“…The presence of TEM, SHV and CTX-M genes alone in the study of Alibi et al in Tunisia was high compared to our results with 3.39% (4/118), 4.23% (5/118) and 11% (13/118) respectively [54]. In Mozambique, on 19 [57]. It is observed that the expression of bla CTX-M is currently more prevalent and as we report for the first time in Togo, more frequent in a triple combination with bla TEM and bla SHV .…”

Dominant plasmids carrying extended‐spectrum β‐lactamases blaCTX‐M genes in genetically diverse Escherichia coli from slaughterhouse and urban wastewaters

“…These plasmids have been largely reported in clinical isolates from humans around the world and more recently from cattle and pets in France, and from the fecal flora of healthy calves in the Netherlands (http://pubmlst.org/plasmid/) (Madec et al ., ; Dahmen et al ., ; Hordijk et al ., ). Their presence in different pathogen species and in different countries (Villa et al ., ; Dahmen et al ., ; Li et al ., ; Rafai et al ., ) suggests that horizontal transfer of plasmids rather than clonal dissemination is probably an important mechanism of bla CTX‐M‐15 spread.…”