Treatment of complex perianal fistulas using leukocyte-and platelet-rich fibrin (L-PRF)

Background Complex anal fistulas (CAF) are associated with high recurrence and risk of postoperative incontinence. Leukocyte- and platelet-rich fibrin (L-PRF) is an autologous biomaterial with pro-healing properties that may serve as a sphincter-preserving adjunct in CAF surgery. Methods Single-center consecutive case series of 16 patients with CAF diagnosed by pelvic magnetic resonance imaging and classified according to Parks. CAF was defined by sphincter involvement and/or complex anatomy. Patients with Crohn’s disease, ASA ≥ III, inadequate follow-up, active infection, rectovaginal or actinic fistulas were excluded. L-PRF membranes were prepared from arterial blood using Choukroun’s protocol and applied along the fistula tract after tract debridement; the internal opening was closed and the external opening was resected. Follow-up visits occurred at 1, 3, 6, and 12 months. Complete cure was defined as clinical closure/epithelialization without discharge at 12 months, confirmed by MRI. Continence was assessed using the Wexner score. Results Mean age was 44 years (SD 12.2); 10 patients were female and 6 male. All fistulas were transsphincteric. At 12 months, 10/16 patients (62.5%) achieved complete cure. Postoperative Wexner score was 0 in 15 patients; one patient had a Wexner score of 12 both pre- and postoperatively (no change) and experienced recurrence. No adverse reactions or procedure-related complications were observed. Conclusions L-PRF application for CAF was feasible and safe, with a 12-month healing rate of approximately 63% and no deterioration in continence. Larger comparative studies are warranted.