Clinical efficacy of autologous platelet-rich plasma (PRP) in canine perianal fistulas and aural hematomas

Platelet-rich plasma (PRP) derived from whole blood, is character- ized by platelet concentrations above baseline in a small volume of plasma that leads to increased concentration of platelet-derived growth factors which can stimulate cell proliferation and decrease the inflammatory reaction accelerating the healing process. The aim of this study was to report the clinical efficacy of autol- ogous PRP obtained with a double centrifugation validated method [1] in the treatment of canine aural hematoma and peri- anal fistula. Dog 1: German shepherd, 11 years old, female, with multiple perianal fistulas, treated with systemic antibiotics and local disinfections without improvement for two months. The dog had 5 perineal fistulas, three of which confluent with each other, with erythema, serum/hematic exudate and dyschezia. Dog 2: Rhodesian ridgeback, 7 years old, female, with monolateral aural hematoma caused by accidental trauma, appeared 21 days before, treated with centesis and corticosteroids therapy, with initial improvement, but subsequent relapse. The dog had an unorga- nized right aural hematoma, size 4.5 9 5 cm, 2 cm thickness. Dog 3: Maltese, 4 years old, male, with monolateral aural hematoma, caused by intense head shaking for bilateral bacterial otitis, appeared 10 days before, treated with centesis and compression bandage, without any improvement. The dog had a partially orga- nized right aural hematoma, size 6 9 5 cm, 3 cm thickness, with 2 areas of necrosis with purulent exudate on the edges of ear pinna, erythema and pain. Procedures and follow up: a medium volume of 0.5 ml of PRP was obtained from a blood sample of 8 ml following a protocol previously described [1]. The autologous PRP was injected 2 times directly into fistulas (0.1 ml for each fistula), while for the aural hematomas it was injected only once after a complete centesis of liquid using the same hole of the drainage inlet. The dogs were checked every 3 days for two week and then two times a month for 2 months to evaluate the improvement with a clinical scoreand photographic documentation. All dogs have a complete heal- ing of the lesions after one month of treatment with PRP, without using other drugs other then antibiotics. No recurrences were observed in one month follow up. Autologous PRP obtained with a in-house double centrifugation method appears to be an effective, minimally invasive therapy in the treatment of perianal fistulas and aural hematoma in dogs.