Systematic Review

The Combined Surgical and Medical Treatment of Fistulising Perianal Crohn's Disease

N. A. Yassin; A. Askari; J. Warusavitarne; O. D. Faiz; T. Athanasiou; R. K. S. Phillips; A. L. Hart


Aliment Pharmacol Ther. 2014;40(7):741-749. 

In This Article

Abstract and Introduction


Background The management of perianal Crohn's fistulas represents a significant challenge. A combination of medical and surgical therapy, guided by radiology, is often required.

Aim To review systematically the literature to assess fistula healing rates with medical treatment (anti-TNF-α therapies ± immunomodulators) or surgical treatment alone, compared with combined medical and surgical treatment in fistulising perianal Crohn's disease (CD).

Methods The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were used. Two independent reviewers searched the literature.

Results Twenty-four articles were included. The total population was 1139 patients; 460 (40%) received single treatment with either medical or surgical therapy, and 679 (60%) received combined medical and surgical therapy. Eight studies compared single and combination therapy, with a total population of 797 patients (single therapy: n = 448, combination therapy: n = 349). In the single therapy group, 191/448 were in complete remission (43%). This was lower than the healing rate of the combination therapy group 180/349 (52%). No response to therapy was noted in 34% (153/448) of the single therapy group compared with 23% (80/349) of the combination group.

Conclusions Combined surgical and medical (anti-TNF-α ± immunomodulators) therapy may have additional beneficial effects on perianal fistula healing in patients with Crohn's disease, compared with surgery or medical therapy alone. A well-designed Crohn's perianal fistula clinical trial is required in a multidisciplinary medical and surgical setting, with clearly defined end points of clinical (and likely patient reported outcomes) and radiological healing.


Perianal fistulas in Crohn's disease represent an aggressive and disabling phenotype and can occur in up to 40% of patients.[1–3] They can have a major negative impact on patients' quality of life.[4,5] The aetiology of fistulising perianal Crohn's disease is unknown, but genetic, microbiological and immune factors have been implicated.

The management of perianal Crohn's fistulas is challenging and often a combination of medical and surgical therapy is required, guided by radiology. Antibiotics[6–8] and immunosuppressive agents such as azathioprine and mercaptopurines[8,9] have been used with varying degrees of success, but the results of the majority of these studies are limited by sample size.

Before the era of biological therapy, approximately 40% of patients had to undergo eventual proctectomy.[10,11] The introduction of anti-TNFα therapies has been encouraging as clinical response rates of up to 68% and complete healing rates of 55% have been reported.[12] Real life data suggest that at long-term follow-up around 33% of patients sustained clinical remission at 3 years follow-up[13] demonstrating an unmet need in the treatment of perianal Crohn's fistulas.

Radiological monitoring of patients on anti-TNFα therapy has demonstrated significant delay between clinical healing, (defined as cessation of fistula discharge) and deep tissue healing (as reported by Magnetic Resonance Imaging (MRI) scanning). There is a lag of around 1 year between clinical and radiological healing.[13]

There are also problems associated with the surgical treatment of perianal fistulas in patients with Crohn's disease. Several studies have demonstrated a significantly high-fistula recurrence rates, citing recurrence of up to 20% for simple and between 25% and 50% for complex perianal fistulas.[6–12]

We systematically reviewed the literature on observational studies assessing the effectiveness of medical treatment (in the form of anti-TNFα therapies ± immunomodulators), surgical treatment and combined medical and surgical therapy in the treatment of fistulising perianal and rectovaginal Crohn's disease.