Antimicrobial Susceptibility Testing and Phenotypic Detection of MRSA Isolated from Diabetic Foot Infection

Khanda Anwar; Dlsoz Hussein; Jamal Salih

doi:10.2147/IJGM.S278574

Antimicrobial Susceptibility Testing and Phenotypic Detection of MRSA Isolated from Diabetic Foot Infection

Int J Gen Med. 2020 Dec 2:13:1349-1357. doi: 10.2147/IJGM.S278574. eCollection 2020.

Authors

Khanda Anwar¹, Dlsoz Hussein², Jamal Salih^{3

4}

Affiliations

¹ Microbiology Department, College of Medicine, University of Sulaimani, Sulaymaniyah, Kurdistan Region, Iraq.
² Microbiology Department, Central Public Health Laboratory 1, Sulaymaniyah, Kurdistan Region, Iraq.
³ Physiology Department, College of Medicine, University of Sulaimani, Sulaymaniyah, Kurdistan Region, Iraq.
⁴ Diabetes and Endocrine Centre, Sulaymaniyah, Iraq.

Abstract

Background: Diabetic foot infection (DFI) is a common and costly complication of diabetes that may be caused by various bacteria with multi-resistant genes. The aim of this study is to evaluate the efficacy of phenotypic methods for identification of methicillin-resistant Staphylococcus aureus (MRSA) with genotypic detection of MRSA-related genes.

Methods: In this cross-sectional study, swab samples were collected from patients with DFI from hospitals in Sulaimani/Iraq in April-July 2019. All the samples were processed for microbiological assessment and further MRSA phenotypic and genotypic testing.

Results: A total of 46 swab samples were collected from diabetic foot ulcers of 29 males and 17 females. Most samples (93.5%) showed positive growth, with higher proportions of monomicrobial (23; 53.5%) than mixed-bacterial infections (20; 46.5%) and S. aureus as the predominant pathogen. Conventional methods of MRSA detection, such as cefoxitin disc diffusion, can predict methicillin resistance in 45.8% of the cases. Real-time/conventional PCR showed that 41.6% of Staphylococcus aureus were positive for the mecA gene, while none of the isolates was positive for PVL.

Conclusion: Staphylococcus aureus was the predominant pathogen in DFI. Although cefoxitin and oxacillin disc diffusion methods can help in the prediction of MRSA, real-time PCR is a reliable method for MRSA detection and confirmation.

Keywords: MRSA; diabetic foot; genotypic detection; infection.

Grants and funding

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. There is no prior presentation of this research work.