Proportion of toxin and non-toxin virulence factors of Staphylococcus aureus isolates from diabetic foot infection: a systematic review and meta-analysis.

BACKGROUND: Staphylococcus aureus isolates are the leading cause of diabetic foot infections (DFIs). Identification of specific virulence factors of S. aureus involved in the pathogenesis of DFIs may help control the infection more effectively. Since the most prevalent virulence factor genes are probably related to the DFI pathogenesis, the aim of this study is to evaluate the proportion of virulence factor genes of S. aureus isolates from DFIs. MATERIALS AND METHODS: We conducted a systematic search of PubMed, Embase, Web of Science, and Scopus to identify all articles reporting the proportion of different types of virulence factors of S. aureus isolates from DFI samples. RESULTS: Seventeen studies were eligible, in which 1062 S. aureus isolates were obtained from 1948 patients and 2131 DFI samples. Among the toxin virulence factors, hld 100.0% (95% CI: 97.0, 100.0%), hlg 88.0% (95% CI: 58.0, 100.0%), hla 80.0% (95% CI: 31.0, 100.0%), hlgv 79.0% (95% CI: 35.0, 100.0%) and luk-ED 72.0% (95% CI: 42.0, 95.0%) had the highest proportion respectively. Among the genes associated with biofilm formation, both icaA and icaD had the highest proportion 100.0% (95% CI: 95.6, 100.0%). CONCLUSION: The results of the present study showed that among the toxin virulence factors, hemolysins (hld, hlg, hla, hlgv) and luk-ED and among the non-toxin virulence factors, icaA and icaD have the greatest proportion in S. aureus isolates from DFIs. These prevalent genes may have the potential to evaluate as virulence factors involved in DFI pathogenesis. Finding these probable virulence factor genes can help control diabetic foot infection more effectively via anti-virulence therapy or preparation of multi-epitope vaccines.

Bacterial Profile and Antimicrobial Resistance Patterns of Infected Diabetic Foot Ulcers in Iran: A Systematic Review and Meta-Analysis of Cross-Sectional Studies.

Since infectious foot ulcers represent one of the major causes of lower-limb amputation, it calls for an appropriate action for early detection and sufficient treatment of diabetic foot infection (DFI). The present study aimed at investigating the bacterial epidemiology and antimicrobial resistance (AMR) patterns of DFIs in Iran. We have conducted a systematic search in PubMed, Embase, Web of Science, Scopus, Google Scholar, and Scientific Information Database to identify all articles reporting the proportion of different kinds of bacteria isolated from Iranian DFI samples. Quality was assessed using Joanna Briggs Institute tool. A pooled estimate of proportion with a corresponding 95% confidence interval (95% CI) was calculated using the random effect method. Fifteen studies were eligible, of which 1970 bacterial isolates were obtained from 1316 patients. The most predominant isolates recovered from DFIs was Staphylococcus aureus with a pooled proportion of 24.29% (95% CI: 20.25%, 28.57%) from which 55% (95% CI: 38%, 72%) were methicillin-resistant S. aureus (MRSA). Among Gram-negative strains, Escherichia coli had the highest proportion (17.19%; 95% CI: 13.96%, 20.68%) followed by Pseudomonas aeruginosa, 7.54% (95% CI: 4.56%, 11.14%). The highest pooled estimates of resistance against cotrimoxazole and ciprofloxacin were found in S. aureus 66% (95% CI: 48%, 82%) and E coli isolates 68% (95% CI: 51%, 84%), respectively. Our study revealed that AMR is at a high level in Iran and clinicians should be aware of bacterial resistance patterns to prescribe appropriate antibiotic regimens.