Journal of Bacteriology & Parasitology

Dissemination of IncF-type plasmids in multi-resistant CTX-M-15-producing Enterobacteriaceae isolates from surgical site infections in Bangui, Central African Republic (CAR)

3^rd International Congress on Bacteriology and Infectious Diseases

August 04-06, 2015 Valencia, Spain

Thierry Frank1, Clotaire Rafai1, Alexandre Manirakiza1, Alfred Gaudeuille2, Jean-Robert Mbecko1, Luc Nghario3, Eugene Serdouma3, Bertrand Tekpa4, Benoit Garin5 and Sebastien Breurec1,6

Posters-Accepted Abstracts: J Bacteriol Parasitol

Abstract:

Introduction: Surgical-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 centers in Bangui, Central African
Republic. We also studied the genetic basis for antibiotic.
Methods: Between 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 centers. The nosocomial bacterial strains were
isolated by using conventional bacteriology and among them; the strains resistant to broad spectrum cephalosporins were
screened for antibiotic resistance genes by direct sequencing. Resistance transfer was studied by bacterial conjugation 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 subtyping
schemes. Multi Locus Sequence Typing (MLST) was used to study the genetic background of E. coli strains.
Results: Of the 165 bacterial isolates collected, most were Enterobacteriaceae (102/165, 61.8%). Of these, 65/102 (63.7%)
isolates were resistant to third generation cephlosporins. The blaCTX-M-15 and aac(6ʹ)-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%). 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.
Conclusion: This study is of particular importance because of the difficulty of carrying out such studies in hospitals in countries
with inadequate health care systems. 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. All necessary measures
should be taken in African hospitals to prevent nosocomial infections and the selection of resistant bacteria with efficient
nosocomial infection surveillance programs.