Next-Generation Sequencing for Pathogen Identification in Infected Foot Ulcers

Area of Science:

• Orthopedics
• Infectious Diseases
• Molecular Diagnostics

Background:

• Diabetic foot ulcers (DFU) present diagnostic challenges due to polymicrobial infections.
• Conventional culture methods can yield inaccurate results (false-positives/negatives), impacting antibiotic treatment.
• Next-generation sequencing (NGS) offers high sensitivity for detecting diverse microbial communities and antibiotic resistance genes.

Purpose of the Study:

• To investigate the utility of NGS for accurate microbial identification and quantification in infected DFUs.
• To compare the microbial profiles obtained by NGS with those from standard culture methods.
• To assess the potential of NGS in guiding postoperative antibiotic therapy for DFU infections.

Main Methods:

• Prospective data collection from 30 infected DFU patients undergoing operative treatment.
• Intraoperative bone specimens processed for both standard culture and NGS.
• Assessment of concordance between NGS and standard culture results.

Main Results:

• NGS identified a higher average number of pathogens per sample (5.1) compared to standard culture (2.6).
• Significant differences in identified microorganisms were observed, with NGS detecting Finegoldia magna as the most common, unlike culture which identified Staphylococcus aureus.
• Pathogen identification by both methods showed a 70% concordance rate in 29 out of 30 patients.

Conclusions:

• NGS provides a more detailed microbial profile than conventional culture for polymicrobial foot infections.
• NGS has the potential to offer valuable information on antibiotic resistance genes.
• Further clinical investigation is warranted to establish NGS in the management of foot and ankle infections.