In Situ Treatment of Refractory Perianal Fistulas in Dogs with Low-Dose Allogeneic Adipose-Derived Mesenchymal Stem Cells

Adult stem cell therapy has demonstrated anti-inflammatory and immunomodulatory effects in many diseases in dogs. This quality gives them great potential for application in immune-mediated diseases such as perianal fistula, where conventional treatments do not guarantee cure. Although there are publications on the use of stem cells in the treatment of this disease, they are scarce and there is no consensus on the application protocol, nor has there been medium and long-term follow-ups, so it is useful to propose new protocols. In this paper, we report a protocol using low doses of adipose stem cells from healthy donors, applied directly to the lesions, which was effective after 1–3 months in all the patients treated (100%), in most cases with a single application and with a follow-up duration of effect of 12–48 months. This proposed protocol is clinically simple, effective, long-lasting, safe, and inexpensive, which is in line with the expectations of dog owners.