Abstract

Objectives: Objectives: Disfiguring scars on the face are known complication after animal bites/dog bite injuries. Early application of adjuvant topical exosome therapy on the primary wound area will expedite wound healing time, reduce the risk of early & hypertrophic scars minimize health care costs, and optimize the patient's quality of life. Introduction: 
Introduction: Exosomes are extracellular microvesicles enclosed by a lipid membrane 30-150nM which carry an abundant amount of growth factors and signaling mediators that enhance all 4 phases of wound healing and scar formation.
Facial injury from dog bites may result in major tissue loss and is a frequent reason for ER visits. Every dog bite is unique and always contaminated, is challenging for surgical repair, and pose a high risk for aberrant scarring and disfigurement. Topical exosomes after primary wound closure is an adjuvant to achieving aesthetically pleasing scar. Materials / method: We report the case of a 49-year-old female who suffered from a serious dog bite on her lower lip. She went to the ER for debridement and primary wound closure and antibiotics. The patient was seen in the clinic 14 hrs later and the wound clot and debris were removed with hypochlorous spray. The MSC-derived exosomes of were topically delivered on the sutured wound using an insulin syringe for over 15 minutes. Daily evaluation of the wound site, signs of infection, pain, itching, and redness were noted by both the patient and the physician, and Photographs were taken. Results: Exosome-assisted wound remodeling, rapid reepithelialization, and attenuation of inflammation result in less aberrant scarring, fibrosis, and almost perfect scarless wound. Our patient showed a significant improvement on Day 10 almost no scaring in 12 months. She has not had any side effects and did not need any scar revisions after 23 months.
 Conclusion: Early application of topical exosomes on the primarily closed wounds after any animal bite-induced facial injury was noted to be safe with no side effects and potentially result in scarless wounds. The exosomes may add the benefit of a reduced rate for scar revisions, reduction of health care costs, and improved quality of life of patients with aesthetically pleasing scars.