Bacterial ecology and antibiotic resistance mechanisms of isolated resistant strains from diabetic foot infections in the north west of Algeria
Résumé
Background In front of the polymorphic bacterial ecology and antibiotic resistance in diabetic patients with foot infections and good patient care, collaboration between clinicians and microbiologists is needed to improve assessment and management of patients with this pathology. Objective This study was designed to characterize the bacterial ecology of diabetic foot infection (DFIs) and to determine the different mechanisms of resistance involved. Methods In this study bacterial strains and antibiotic resistance profiles were determined from diabetic foot infections patients (n = 117). The identification of resistance mechanisms, such as penicillinase and/or extended-spectrum beta-lactamase production (ESBL), methicillin-resistantStaphylococcus aureus(MRSA) and efflux pump over-expression were performed. Results A high prevalence of Gram-negative bacteria (61%) withEscherichia coli,and other Enterobacteriaceae andPseudomonas aeruginosabeing the predominant isolates. Gram positive bacteria mainly represented byStaphylococcus aureusaccounted for 39% of the isolates. 93.5% of theEnterobacteriaceaewere resistant to, at least, one molecule in the beta-lactam family, while the majority of theStaphylococciwere resistant to penicillin G and tetracycline (93.3% and 71.7%). The majority of non-fermenting Gram negative bacteria were also resistant to fluoroquinolones. beta-lactamase detection tests revealed the presence of extended-spectrum beta-lactamase in 43.5% of theEnterobacteriaceae,while methicillin-resistantStaphylococcus aureusrepresented 18.2% of the isolates. Additionally, 50.9% of non-fermenting Gram negative bacteria were overproducing efflux pumps. Conclusion AllAcinetobacter Baumanniiwere Multidrug-Resistant (MDR), as the majority ofStaphylococci,and Enterobacteriaceae. These results should be taken into account by the clinician in the prescription of probabilistic antibiotic therapy in this context.