Activity of beta-lactam antibiotics and production of beta-lactamases in bacteria isolated from wound infections in Brazzaville, Congo

Abstract

To determine the mechanism of bacterial beta-lactam resistance, 165 bacteria isolated from wounds of hospitalized patients composing of: 42 Staphylococcus aureus, 37 Pseudomonas aeruginosa, 23 Escherichia coli, 22 Proteus, 12 Klebsiella, 10 coagulase-negative staphylococci (CNS), eight Enterobacter, six Citrobacter, five Providencia were tested for their sensitivity to beta-lactams and their production of beta-lactamases. The antibiotic susceptibility was considered by the method of the standard diffusion on agar Mueller Hinton. The rate of production of ß-lactamase in all bacteria was determined using the Strips of nitrocefin. The percentages of resistance to beta-lactams obtained were as follows: Staphylococcus aureus (77.90%), Pseudomonas aeruginosa (44.14%), E. coli (73.8%), Proteus (57.4%), Klebsiella (63.6%), CNS (57.15%), Enterobacter (56.3%), Citrobacter (83.3%), Providencia (67.5%). The rate of beta-lactamases were as follows: S. aureus (7.34%), P. aeruginosa (89.19%), E. coli (95.65%), Proteus (86.36%), Klebsiella (91.67%), CNS (90%), Enterobacter (87.5%), Citrobacter (66.67), Providencia (100%). The studied bacteria produce beta-lactamases which is the primary mechanism of resistance to beta-lactam antibiotics in the majority of the bacteria. Beta-lactamases rates vary from one genus to another. It is extended spectrum beta-lactamase-producing strain.

Antibiotic Resistance Phenotypes of <i>Enterobacteriaceae</i> Isolated from Household Wastewater in Brazzaville, Republic of Congo

“…In this study, the rates of resistance to ceftriazone and imipenem in E. coli strains were 0% and 12.5%, respectively. These frequencies are in disagreement with those reported by Mpelle et al [11] on E. coli, whose respective rates are 79.07% and 0%, and by Moyen et al [13] 73.9% and 4.3%. Oubrim et al [14] reported a zero resistance rate for the same antibiotics tested.…”

“…We reported 100% resistance rates in E. coli to amoxicillin, amoxicillin + clavulanic acid, cefalotin, ceftazidime and nalidixic acid. Lower percentages of resistance were reported by Passerat et al [12] 25%, 15%, 20%, 0% and 25% respectively; Moyen et al [13] reported 100%, 87%, 87% for amoxicillin, amoxicillin acid/clavulanic acid, cefalotin and ceftazidime. In this study, the rates of resistance to ceftriazone and imipenem in E. coli strains were 0% and 12.5%, respectively.…”

Antibiotic Resistance Profile of Pathogenic Bacteria Isolated from “Mabokés” Smothered Fish in Brazzaville, Congo

“…All E. coli strain isolates were resistant to Cefrazidime. This differs from rate of resistant of 77.3% reported by [19] on E. coli isolated at the CHUB. [20] in the Republic of Congo working on E. coli isolated from CHUB inpatients and outpatients reported resistance rates of 46.51%, 37.20%, 34.88% 13.95% and 46.51% respectively for piperacillin-tazobactam, cefepime, gentamicin, ciprofloxacin and fosfomycin in the extended-spectrum beta-lactamase producing strains.…”

First report of the types TEM, CTX-M, SHV and OXA-48 of beta-lactamases in Escherichia coli, from Brazzaville, Congo

“…Classes A and D enzymes are commonly found in Africa with a predominance of blaCTX-M-15 (Storberg, 2014). In Congo-Brazzaville, a prevalence of 73.8% of E. coli strains harboring beta-lactamase phenotype was reported (Moyen et al, 2014). To our knowledge, no study has been performed on the characterization of Enterobacteriaceae resistance genes.…”