Radiofrequency thermocoagulation for high transphincteric fistulae, Merlini l'Héritier et al.

Abstract

Obliteration of the internal opening has long been held as the key resolution of high transsphincteric fistulae. This month's Editor's Choice by Merlini l'Héritier et al. evaluated ablation of the tract by applying radiofrequency thermocoagulation 1. They used a control group, selected from a prospective database consisting of patients who underwent occlusion of the fistula tract by a rectal advancement flap, paired-matched for sex, age and the presence of Crohn's disease. The healing rate was only 26% at 5 months after radiofrequency thermocoagulation, vs 68% after flap repair, and dropped further to 10% after 21 months. These findings suggest that obliteration of the fistula tract is not enough to accomplish healing of perianal fistulae in most cases. The authors must be congratulated on publishing these findings. Negative findings provide much needed feedback on the effectiveness of treatment after introducing a new technique or pursuing new indications for a known technique. Radiofrequency thermocoagulation has become common practice as the primary treatment of varicose veins. Recently, new indications for the radiofrequency technique have been defined. For example, obliteration of the sinus in simple pilonidal disease with radiofrequency has been shown to be highly successful 2. We now know that pilonidal disease is caused by loose hairs entering the pits in the intergluteal cleft by their root ends, where a foreign body reaction creates the pilonidal sinus. Consequently, it is understandable that after removing the hairs from the pilonidal cavity, obliteration of the pits by thermocoagulation in order to avoid future potential ports of hair re-entry is a sound treatment principle. The pathophysiology of cryptoglandular and Crohn's fistulae has not been conclusively established. Crohn's disease is thought to be caused by a failure of the intestinal mucosal immune system to tolerate commensal bacteria. The highest healing rates in the featured study were achieved in patients with Crohn's disease (overall success 64 percent) 1. All these patients were on anti-tumour necrosis factor alpha therapy. There is now growing evidence that in patients with Crohn's fistulae, it is essential to combine surgery with biologic agents 2, 3. When managing Crohn's fistulae, combining a surgical procedure, which prevents entry of bacteria to the fistula, with immunotherapy seems to be the logical approach. The overall healing rate in patients with cryptoglandular fistulae was only 41% at 5 months follow-up 1. The persistent inflammation in the anal crypt is nowadays believed to occur as a result of a defective local immune system. Hence, before introduction of new surgical techniques, a better understanding of what process drives this ongoing perianal sepsis is recommended.