Abstract
Background
The efficacy of injections of mesenchymal stem cells (MSC) for anal fistula treatment may be impaired by the persistence of stools passing into the fistula, causing bacterial contamination and a local inflammatory reaction. We aimed to compare remission rates between patients treated by MSC injection with simple sutures and those treated with a rectal advancement flap.
Methods
This single-center prospective study compared the first patients who underwent internal opening closure with sutures, with the subsequent patients treated with a flap. Complete clinical remission was defined as complete closure of the external opening(s) without pain or discharge, and complete radiological remission was defined as a Magnifi-CD score of 0.
Results
We compared the first 42 patients who had sutures with the 20 subsequent patients who had an advancement flap. The median follow-up was 15.5 months [8.8–24.9 months]. The cumulative incidence of complete clinical response at M12 was 53.8% [38.1–69.6%] in the suture group versus 93.3% [77.4–100.0] in the flap group (p < 0.001). The Magnifi-CD score was 0 for 72.7% [39.0%-63.9%]) of patients treated with a flap versus 41.7% [25.5%-59.2%]) of patients treated with sutures (p = 0.093). Anal incontinence score did not differ between the 2 groups. Practicing an advancement flap was the only significant factor associated with complete clinical remission over time (adjusted HR [95% CI] of 2.6 [1.4–4.9], p = 0.003).
Conclusions
Complete clinical remission rates following MSC injection are significantly higher for the closure of the internal opening with a rectal flap than for closure with sutures, with no consequences for anal continence.