Endoscopic ultrasound for perianal Crohn's disease: disease and fistula characteristics, and impact on therapy.

BACKGROUND AND AIM Appropriate treatment of perianal fistulas in Crohn's disease (CD) involves accurate anatomic evaluation. EUS is an accepted imaging method for this purpose. The aim of the current study was to evaluate the clinical and endosonographic characteristics of perianal fistula in CD and to assess its impact on therapy. METHODS All CD patients referred to the Sheba medical center from June 2004 to August 2008 for EUS examination of perianal fistulas were included. Perianal fistulas were diagnosed based on a clinical examination revealing at least one perianal cutaneous orifice. Demographic, clinical and therapeutic data was obtained. EUS was performed using an ultrasound scanner producing a 360° cross sectional image of the anal sphincters. RESULTS Fifty six patients were included in the study. Four patients were excluded from the final analysis: 3 because no fistula could be detected by EUS, and one due to inability to tolerate the examination. The mean CD duration was 10±9.16 years (range 1-37). Mean perianal disease duration was 5.3±6.5 (range 1-29) years. 27 patients had perianal involvement at presentation. Among the fistulas diagnosed, 13 were simple (25%) and 39 were (75%) complex. No correlation was found between CD duration or location, patients' age and gender or fistula location with fistula type or complexity. EUS results influenced patient management in 86% of the patients. CONCLUSIONS CD-associated perianal fistulas are mainly complex. EUS is a well tolerated and informative imaging modality, with significant impact on treatment.