Platelet-rich plasma (PRP) versus fibrin glue in cryptogenic fistula-in-ano: a phase III single-center, randomized, double-blind trial.

Purpose: To compare the clinical outcome of autologous platelet-rich growth factor (PRP) with commercial fibrin glue in the management of high cryptogenic fistulae-in-ano.

Method: The study was conducted at a single center between July 2012 and July 2015 and performed as a phase III, randomized, double-blind comparison of autologously prepared PRP versus fibrin glue for cryptoglandular anal fistulae without active sepsis. Patients were assessed with clinical and endosonographic follow-up. Patients were followed up at 1 week and then at 3, 6, and 12 postoperative months. The primary outcome measure was the fistula healing rate (complete, partial, and non-healing) with secondary outcome measures assessing fistula recurrence, continence status, quality of life, and visual analog pain scores.

Results: Of the 56 enrolled patients, 32 were PRP-treated and 24 were fibrin-treated. The groups were well matched for fistula type with an improved overall healing rate for PRP-treated over fibrin-treated cases (71% vs. 58.3%, respectively; P = 0.608); a complete healing rate of 48.4% vs. 41.7%, respectively; and a partial healing rate of 22.6% vs. 16.7%, respectively. The median pain scores of PRP-treated patients were lower at the first visit with a greater initial pain decrease early during follow-up. Improvements in pain reduction impacted the quality of life measures (P = 0.035). All adverse events were minor and no patient experienced a negative impact on continence.

Conclusion: Treatment of complex cryptoglandular anal fistula with autologous PRP is as effective as fibrin glue with less cost and no adverse effect on continence.