Long-term Outcomes of Primary Fistula Closure with Platelet-Rich Plasma: A Prospective Study

BACKGROUND: Treating complex perianal fistula remains a challenge and finding surgical techniques that guarantee high cure rates without compromising continence is necessary. Plateled rich plasma has been studied in different disciplines, with treatment being successful due to its properties as a tissue regenerator. OBJECTIVE: To assess the 5-year cure rate and complications among patients with complex perianal fistula treated with plasma therapy. DESIGN: A prospective, observational study conducted from 2011 to 2022. Patients with complex perianal fistula who met the inclusion criteria were treated with plasma rich in growth factors. Follow-up and assessment were performed for 5 years after treatment, with visits at 1, 3, 6, 12, 36, and 60 months. SETTING: This study was conducted at a single tertiary referral centre. PATIENTS: Data from 166 patients were assessed. MAIN OUTCOME MEASURES: The primary outcome measure was the rate of fistula healing and the secondary outcome measures assessed recurrence, continence status, and complications. RESULTS: A total of 166 patients with cryptoglandular complex perianal fistula (68.7% male, mean age 51.4 ± 13.2 years) were included. The majority of the fistulas (88.5%) were trans-sphincteric; 87.8% were relapsed fistulas, with a mean of 3.3 ± 3.1 previous procedures. The median time to recurrence-free healing was 26 ± 5 months (95% CI: 16-36). The 1-year follow-up was completed by 154 patients, 3-years by 140 patients, and at 5-years by 91 patients. The estimated healing rate decreased over time reaching 70.9% at 1 year, 42.8% at 3 years, and 24.3% at 5 years. Complications were absent in 92.7% of the cases. No changes in continence were observed in any patients. LIMITATIONS: Most patients presented with trans-sphincteric anal fistulas. CONCLUSIONS: Treatment of complex cryptoglandular anal fistula with platelet rich plasma is safe and feasible in the long term. See Video Abstract .