Effect of bioactive glass wound matrix on small fiber neuropathy density in non-healing diabetic foot ulcers

Introduction: It is estimated that 10 million people worldwide are affected by small fiber neuropathy which involves damage primarily to small unmyelinated C sensory fibers and myelinated alpha delta fibers. Synthetic materials such as bioactive glass are known to promote neurite extension and sustain neuronal health are becoming commercially relevant as the next generation of skin substitutes. Small nerve density of non-healing diabetic wounds treated with bioactive glass wound matrix was studied in six non-healing diabetic patients who did not respond favorably to standard of care therapy.Methods:A case series of six patients with non-healing diabetic ulcers underwent an epidermal nerve fiber density biopsy before and after application of bioactive glass wound matrix to determine if there is a change in small fiber nerve density post therapy. All patients presented with non-healing diabetic ulcerations failed to heal by standard of care therapy. Patient neuropathy was confirmed clinically as per the first epidermal skin nerve biopsy obtained from the skin adjacent to the ulceration. Subsequently, ulcerations were treated with a bioactive glass wound matrix until resolved. Once wounds resolved, a second skin biopsy was obtained at or near the healed ulceration and/or first skin biopsy site and the small nerve density compared to the initial density measurement.Results:All six non-healing diabetic wounds resolved after application of the bioactive glass wound matrix. Of these resolved wounds, three wounds had an increased small nerve fiber density, two wounds further decreased in small nerve density, and one wound had no measurable change as compared to the initial biopsy prior to the application of bioactive glass wound matrix.Discussion: Improvement in nerve function is typically uncommon in diabetic neuropathic patients. however, a significant neuropathic response (250% increase) was reported over the standard of care in a 40-patient randomized controlled trial on diabetic foot ulcers treated with bioactive glass wound matrix. Patients with painful wounds have also reported a significant reduction in pain after the application of bioactive glass wound matrix. The improvement seen in the small nerve density of three of these six diabetic patients is a significant result that is consistent with previous works that reported improved nerve function and warrants additional investigation. While the number of wounds in this series is small, it provides sufficient data to suggest that a larger and more controlled study could be warranted to further study the effect bioactive glass wound matrix has on small nerve neuropathy.References: