Bacterial biofilms are known to pose hindrance to wound healing by forming a physical barrier to wound closure and also by hyperactivating local inflammatory processes. Biofilm removal thus becomes a priority in wound care. Addition of topical oxygen to standard wound care has been shown enhance healing of Texas Grade II and III diabetic foot ulcers (DFUs). This was speculated to be a result of alterations of the wound microbiome or biofilm.

The present study was designed to ascertain the mechanism of action of topical oxygen in DFUs. Investigators assessed the diversity of bacterial genera present in DFUs treated with topical oxygen.

The wounds of 6 patients with chronic DFUs were swabbed weekly over 8 weeks of continuous topical oxygen treatment. The microbiome diversity was assessed by metagenomic 16S rDNA sequencing with the help of a next-generation sequencing platform.

In 5 healed wounds, the wound microbiome was shown to shift towards a diverse flora that was dominated by aerobes and facultative anaerobes with oxygen therapy. Anaerobic flora appeared to persist in a single nonhealing ulcer.

Despite the sample size being small, the study highlights the role of topical oxygen therapy in promoting the growth of aerobes in the wound microbiome. Topical oxygen therapy could be a promising alternative to antibiotics in this area.

Source: Hunter P, Greco E, Cross K, Perry J. Topical Oxygen Therapy Shifts Microbiome Dynamics in Chronic Diabetic Foot Ulcers. Wounds. 2020 Mar;32(3):81-85.