DNA Diagnosis of Microorganisms in Wound Biofilm and Topical Antibiotic Treatment A Successful Approach to a Difficult Problem

Introduction: Wound healing can be a challenging and complex problem for some patients.  In persistent non-healing wounds, the healing process is often confounded by colonizing bacteria and subsequent biofilm formation. Up to 78% (Schultz, et al 2017) of all chronic wounds are estimated to contain biofilm, which renders bacteria difficult to isolate in culture and more tolerant to many topical wound treatments. Targeted microbial DNA sequencing offers the ability to comprehensively identify microbes which may be complicating the healing process. DNA guided therapy allows for a patient-specific diagnosis and can be combined with personalized topical antibiotic compounds to treat wounds more successfully. Methods:We present 15 distinct patients with 18 specific chronic wounds that were not healing.  These patients had failed various other treatment modalities including topical antiseptics, topical antibiotics, and various other standard wound products.  Other standard wound care practices such as debridement, compression, off-loading, nutritional support, and arterial and venous optimization were followed according to our institutional guidelines.  Patients were tested for microbial components within a biofilm using DNA swab* and then started on a topical antibiotic mixed with lipogel based on the microbial DNA results.  Wound area measurements were compared prior to starting treatment, at the time of testing, and at two time points following.Results: All of these complex wounds were positive following microbiological profiling and were switched to daily topical antibiotic mixed with lipogel.  The average patient in this case series healed greater than 50% in 8 weeks after initiation of topical antimicrobial therapy mixed with lipogel  and 42% of patients were completely healed by 6-30 weeks. There was no consistent change in wound area prior to starting NGS-guided therapy. Discussion: Most patients in this case series saw significant improvement or healed completely using topical DNA-guided antibiotic regimen.  Our case series supports the use of molecular diagnostics and topical antibiotic treatment to heal persistent nonhealing wounds. References:Schultz G, Bjarnsholt T, James GA, Leaper DJ, McBain AJ, Malone M, Stoodley P, Swanson T, Tachi M, Wolcott RD; Global Wound Biofilm Expert Panel. Consensus guidelines for the identification and treatment of biofilms in chronic nonhealing wounds. Wound Repair Regen. 2017 Sep;25(5):744-757. doi: 10.1111/wrr.12590. Epub 2017 Dec 12. PMID: 28960634.