Published online Nov 14, 2018. doi: 10.3748/wjg.v24.i42.4821
Peer-review started: July 26, 2018
First decision: August 27, 2018
Revised: September 24, 2018
Accepted: October 21, 2018
Article in press: October 21, 2018
Published online: November 14, 2018
To systematically review the literature on epidemiology, disease burden, and treatment outcomes for Crohn’s disease (CD) patients with complex perianal fistulas.
PubMed, Embase, and Cochrane were searched for relevant articles (published 2000-November 2016) and congress abstracts (published 2011-November 2016).
Of 535 records reviewed, 62 relevant sources were identified (mostly small observational studies). The cumulative incidence of complex perianal fistulas in CD from two referral-centre studies was 12%-14% (follow-up time, 12 years in one study; not reported in the second study). Complex perianal fistulas result in greatly diminished quality of life; up to 59% of patients are at risk of faecal incontinence. Treatments include combinations of medical and surgical interventions and expanded allogeneic adipose-derived stem cells. High proportions of patients experience lack of or inadequate response to treatment (failure and relapse rates, respectively: medical, 12%-73% and 0%-41%; surgical: 0%-100% and 11%-20%; combined medical/surgical: 0%-80% and 0%-50%; stem cells: 29%-47% and not reported). Few studies (1 of infliximab; 3 of surgical interventions) have been conducted in treatment-refractory patients, a population with high unmet needs. Limited data exist on the clinical value of anti-tumour necrosis factor-α dose escalation in patients with complex perianal fistulas in CD.
Complex perianal fistulas in CD pose substantial clinical and humanistic burden. There is a need for effective treatments, especially for patients refractory to anti-tumour necrosis factor-α agents, as evidenced by high failure and relapse rates.
Core tip: Complex perianal fistulas in Crohn’s disease (CD) impose considerable burden. Rates of failure and relapse are generally high with currently available treatments. Effective treatment options for complex perianal fistulas in patients with CD, especially those who are refractory to anti-tumour necrosis factor-α agents, are needed.