A systematic review of new treatments for cryptoglandular fistula in ano.

AIM: In 2007 the ACPGBI published a position statement on the management of cryptoglandular fistula in ano. Over the last seven years a number of new treatments have been developed and the aim of this systematic review was to assess their effectiveness. METHOD: A systematic review of all English language literature relevant to novel treatment strategies for cryptoglandular fistula in ano, published between 1 January 2007 and 31 Dec 2014 was carried out using MEDLINE (PubMed and Ovid), EMBASE (Ovid) and the Cochrane Library of Systematic Reviews/Controlled Trials for relevant literature. Technical notes, commentaries, letters and meeting abstracts were excluded. The different treatments were assessed with regards to fistula closure rate in relation to length of follow up and reported complications. RESULTS: Seventy potential articles published between 1 January 2007 and 31 December 2014 were identified from the initial literature search. Twenty-one articles were included for final analysis although only two were randomized controlled trials, the remainder being retrospective or prospective series. CONCLUSION: This systematic review has demonstrated that whilst there have been technological advances to treat complex cryptoglandular fistula in ano, these are in an early stage of evolution and although early results were promising they are difficult to reproduce. Longer follow up data is not currently available and these treatments should not be introduced without further evidence.

The proposed use of radiofrequency ablation for the treatment of fistula-in-ano.

Fistula in ano is a very common presentation to colorectal clinic. Embarrassment due to the symptoms makes accurate estimations of incidence difficult. It is estimated that up to 40% of peri-anal abscess will be accompanied by or preceded by a fistula. Fistulae can be classified into simple fistulae that involve no or minimal sphincter muscle and complex, which involve significant amounts of the anal sphincter muscle, possibly with multiple tracts. For complex fistulae a seton suture is usually placed through the tract and out through the anus to form a loop allowing pockets of sepsis to drain internally and externally and a mature tract of fibrous tissue to develop. Following this period definitive fistula treatment is considered. This can involve a number of procedures that have tremendously varied success rates in the literature. The first stage of surgical treatment is often a core fistulectomy, which entails surgical removal of the tract. This may be followed by insertion of fibrin glue, a collagen plug or formation of a rotation skin flap from surrounding tissue in order to close the resultant tissue defect. All current treatments have a significant failure rate. If this wound breaks down the surgery can leave a large painful peri-anal wound that can lead to ongoing fistulation. Should this occur resiting of the seton will be required with the patient only getting back to square one after months of healing around the seton. In addition removing cores of fibrous tissue passing through the sphincter can threaten the sphincter function resulting in impaired continence. Having seen radiofrequency ablation used to close varicose veins the authors propose that one could use similar techniques to close a fibrous tract matured with a seton in order to close a fistula. The authors propose that a short length radiofrequency catheter could be used to treat fistula in ano. This would in theory be less painful with less tissue destruction. In addition there would be no necessity for extensive incisions. As the energy penetration can be controlled the procedure will be safe even if it fails, without causing a large wound or tissue necrosis. All other treatment options will still be available.