P303 Local Application of Autologous Platelet-rich Plasma leads to Sustained Healing of Crohn`s Perianal Fistulae – One Year follow-up Results from a Single Center Pilot Study.

Podmanicky, D.(1,2);Jezberova, M.(3);Lucenicova, J.(4);Bak, V.(1);Kadleckova, B.(5);Zelinkova, Z.(5);

(1)University Hospital-St Michael`s Hospital, Department of General Surgery, Bratislava, Slovakia;(2)Slovak Medical University, Faculty of Medicine, Bratislava, Slovakia;(3)Dr. Magnet ltd., Dpt of Magnetic Resonance Imaging, Bratislava, Slovakia;(4)University Hospital-St Michael`s Hospital, Laboratory of Hematology and Biochemistry-, Bratislava, Slovakia;(5)University Hospital-St Michael`s Hospital, Dpt of Gastroenterology and Digestive Endoscopy, Bratislava, Slovakia

Background

Failure of wound repair and dysregulated inflammation in considered to play a key role in the persistence of Crohn`s perianal fistulae (pCD). Few preliminary reports suggest that autologous platelet-rich plasma (PRP) can enhance wound repair and may be effective in treating pCD. Therefore, the aim of our study was to determine the efficacy of autologous PRP in the treatment of pCD.

Methods

A prospective, uncontrolled, single center study in a referral IBD center was conducted between July 2018 and March 2021. Adult Crohn´s disease patients with pCD failing on antibiotics, immune suppression and/or biologics were eligible for the study. All patients had non-cutting setons for a minimal period of 6 weeks prior study intervention. Autologous PRP was separated by centrifugation 60 ml of peripheral blood in Harvest SmartPrep© System at the time of operation. After the seton removing, internal openings were closed by PDS 2/0 single suture and PRP was injected close to internal openings and fistula tracts. Patients were examined at outpatient clinic at week 1, month 1, 3, 6 and 12. Any suspected side-effects of the treatment were noted. Treatment effect was assessed by perianal Crohn Disease Activity Index (PCDAI assessed at baseline, month 1, 3, 6, 12) and van Assche MRI score (assessed at baseline and month 6 and 12).  The primary end-point was complete healing at month 6 defined as closure of all external fistula openings and absence of abscess on MRI. The secondary end-point was sustained response at month 12.

Results

In total, 25 patients (pts) with pCD were included (mean age 36 years, range 21-61; 15 men). The majority of pts were using antiTNF biologics (9 adalimumab, 9 infliximab), 4 pts were treated by ustekinumab, one by vedolizumab, two patients were on immunomodulators monotherapy. By March 2021, 24 patients finished the 6 months and 21 patients the 12 months follow-up. The primary end-point of complete healing at month 6 was reached by 18 out of 24 pts (75%). All but one patients with complete healing had persistent complete healing at 12 months follow-up. Baseline PCDAI (median 5, range 2-15) decreased significantly as early as at month 1 (median 1, range 0-8; p<0.001) and remained further stable over 12 months. Van Assche MRI score decreased significantly from median of 9 (range 3-18) at baseline to 5 (range 0-18)  and 5.5 (range 0-18) at month 6 (p=0.001) and 12 (p=0.03); respectively.

Conclusion

Local application of autologous platelet-rich plasma leads to rapid healing of difficult-to-treat Crohn`s perianal fistulae in 75% of patients and this effect is sustained up to minimal period of one year.