Anal fistulas

Abstract The objective of modern anal fistula treatment is healing of the fistula without diminished fecal continence. Sphincter saving techniques have been developed for anal fistulas, for which fistulotomy is not suitable. Treatment of these anal fistulas remains challenging and to some extent disappointing. The aim of the studies described in this thesis is to evaluate treatments for anal fistulas and to gain a better understanding of the pathogenesis of anal fistulas. Despite our effort it seems unlikely that surgical treatment alone will ever lead to fistula healing in all patients. The outcomes of the studies in this thesis made us suggest that inflammation plays a role. Treatment of anal fistulas may need a new approach, combining surgery with treatment of inflammation

Pro-inflammatory cytokines in cryptoglandular anal fistulas

Background: Sphincter-preserving procedures for the treatment of transsphincteric fistulas fail in at least one out of every three patients. It has been suggested that failure is due to ongoing disease in the remaining fistula tract. Cytokines play an important role in inflammation. At present, biologicals targeting cytokines are available. Therefore, detection and identification of cytokines in anal fistulas might have implications for future treatment modalities. The objective of the present study was to assess local production of a selected panel of cytokines in anal fistulas, including pro-inflammatory interleukin (IL)-1β and tumor necrosis factor α (TNF-α). Methods: Fistula tract tissue was obtained from 27 patients with a transsphincteric fistula of cryptoglandular origin who underwent flap repair, ligation of the intersphincteric fistula tract or a combination of both procedures. Patients with a rectovaginal fistula or a fistul