Management of intersphincteric abscesses

Intersphincteric abscesses are relatively rare, and in some cases of upward extensions in the supralevator plane, can be difficult to manage. The aim of this study was to analyse the type of treatment used in these abscesses.

Twenty-one intersphincteric abscesses treated by endoanal drainage in our colorectal unit between 1992 and 2004 were reviewed from our database; location and extension of the abscess, type of treatment and recurrence rates and the use of endoanal ultrasound were studied.

Ninety per cent of patients were male; 10 had a previous history of surgery for perianal abscess and suppuration (48%); 16 (76%) had a posterior location and five were anterolateral. Twelve patients had low intersphincteric abscesses and were treated by laying open the abscess and dividing the internal sphincter. Nine were found to have high extensions into the intermuscular planes and were treated by staged procedures: a temporary transanal mushroom catheter was used in seven patients. Endoanal ultrasound was used initially in seven patients (33.3%) and for the evaluation of definitive treatment in 11 (52%).

Low intersphincteric abscesses should be treated by de-roofing of the abscess and division of the internal sphincter up to a level of the dentate line. High intersphincteric abscesses are relatively frequent and mostly require staged surgery with a temporary mushroom (de Pezzer) catheter. Accurate anatomical ultrasound localization and proper drainage become important to avoid recurrences or extrasphincteric fistulas.