Background: Treatment of perianal fistulizing Crohn's disease (PFCD) is challenging. Placement of a draining seton as the first step is considered gold standard therapy. The aim of this study was to determine the long-term efficacy of draining setons in PFCD.
Methods: Charts of patients with PFCD treated with a draining seton over a five-year period ending November 2015 were reviewed. Patients were primarily treated with silastic seton without planned future seton removal or fistula repair. Short-term (<6 months from the time of initial seton placement), intermediate-term (<12 months from the time of initial seton placement), and long-term (>12 months from the time of initial seton placement) outcomes were analyzed.
Results: The study cohort included 41 patients. Indication for placement of draining seton alone rather than definitive surgical fistula repair was presence of anal ulceration, stenosis and/or proctitis (n=30; 73%), complex fistulae not amenable to surgical repair (n=8; 26%) or patient preference (n=3; 7%). Concomitant medical therapy using biologics, immunomodulators, and/or steroids was used in 28 (68%), 14 (34%) and 13 (32%) patients, respectively. Median length of follow-up after seton placement was 35 months (range, 8–69). Over the short-term, 16/41 (39%) patients required additional seton placement for new or persistent fistula after median follow-up time of 2.2 months (range, 0.2–5.5 months). Over the intermediate-term, 6/37 (16%) more patients required additional seton placement for new or persistent fistula after a median follow-up time of 7.7 months (range, 7–11.4 months). Over the long-term, 7/35 (20%) more patients required additional seton placement for new or persistent fistula after a median follow-up time of 16.8 months (range, 14.5–29.5 months). Overall, 29 (71%) patients required additional seton placement for new or persistent fistula after a median time of 7 months (range, 0.2–29.5 months) after initial seton placement (Figure 1). The majority of patients requiring additional seton placement also had concomitant medical therapy with a biologic agent (19/29; 66%). Patients who had a family history of CD had a significantly lower incidence of additional seton placement (50%) compared to patients who did not have a family history of CD (90%) (p=0.04). All other clinical factors including concomitant medical therapy were not associated with additional seton placement.
Conclusions: Almost 75% of patients with planned long-term seton drainage for PFCD required additional setons. These data suggest that draining setons in PFCD, even in combination with biologic agents, may not have as promising results as previously believed. Progression of PFCD remains high despite biologic therapy and seton drainage.