Phenotypic Characterization of Methicillin-Resistant Staphylococcus spp (MRS) Strains Isolated from Diabetic Foot Wounds at Yaounde Central Hospital
Assiene Oyong Damase Serge *
Department of Biology, Higher Institute of Medical Technology of Yaounde, Yaounde, Cameroon and Department of Biological Science, Faculty of Medicine and Pharmaceutical Sciences, University of Douala, Douala, Cameroon.
Albert Essimi
Department of Biology, Higher Institute of Medical Technology of Yaounde, Yaounde, Cameroon.
Bamia Aline
Department of Biological Science, Faculty of Medicine and Pharmaceutical Sciences, University of Douala, Douala, Cameroon.
Cedric Gueguim
Department of Biology, Higher Institute of Medical Technology of Yaounde, Yaounde, Cameroon and Department of Environmental Sciences, Higher Institute of Agriculture, Wood, Water and the Environment, University of Bertoua, Belabo, Cameroon.
Laurent Akono
Department of Biology, Higher Institute of Medical Technology of Yaounde, Yaounde, Cameroon.
Megne Mimbe Lys Cannella
Department of Biology, Higher Institute of Medical Technology of Yaounde, Yaounde, Cameroon.
Lucien Honoré Etame Sone
Department of Biology, Higher Institute of Medical Technology of Yaounde, Yaounde, Cameroon and Institute of Medical Research and Medicinal Plants Studies, Yaounde, Yaounde, Cameroon.
Dieudonné Adiogo
Department of Biology, Higher Institute of Medical Technology of Yaounde, Yaounde, Cameroon and Department of Biological Science, Faculty of Medicine and Pharmaceutical Sciences, University of Douala, Douala, Cameroon.
*Author to whom correspondence should be addressed.
Abstract
Background: Diabetic foot infections are a major public health concern and are frequently complicated by multidrug-resistant bacteria. Staphylococci, particularly methicillin-resistant strains (MRS), are among the most commonly encountered pathogens.
Aim: This study aimed to determine the prevalence of MRS in diabetic foot wounds, characterise their resistance profiles, and identify phenotypes associated with multidrug resistance.
Methods: A cross-sectional study was conducted among 112 patients with diabetic foot wounds at Yaoundé Central Hospital between March and July 2021. Samples were analysed using culture, biochemical identification (API Staph), and disc-diffusion susceptibility testing. hVISA and GISA phenotypes were screened using the ROSCO method. Data were analysed using Epi InfoTM7 and Excel software, with statistical significance set at p < 0.05.
MRS were detected in 60.71% (68/112) of samples. The highest resistance rates were observed for β-lactams (99.26%) and aminoglycosides (91.17%), whereas nitrofurantoin (97.08%) and rifampicin (79.4%) showed the highest susceptibility rates. Among the 68 isolates, 25 (36.76%) were multidrug-resistant to more than seven antibiotic families (p = 0.001). The most frequent species were S. hominis (28%), S. epidermidis (16%), and S. xylosus (16%). GISA (60%) and hVISA (36%) phenotypes were detected, and some strains were also resistant to daptomycin.
Conclusion: Methicillin resistance in diabetic foot infections in Cameroon is not restricted to S. aureus but also involves clinically significant coagulase-negative staphylococci. These findings support expanded antimicrobial resistance surveillance and the adaptation of therapeutic protocols to local resistance patterns.
Keywords: Diabetic foot infection, methicillin-resistant Staphylococcus spp., coagulase-negative staphylococci, antimicrobial resistance, multidrug resistance, glycopeptide-intermediate phenotype, heterogeneous vancomycin-intermediate phenotype, phenotypic characterisation.