P146 Ultrasonography and perianal involvement in inflammatory bowel disease

Abstract

Background: Ano-rectal ultrasonography (AR-EUS) is an accurate, simple and well-tolerated method for assessing perianal complications of inflammatory bowel disease (IBD). The aim of this study is the characterisation of AR-EUS findings in patients with IBD. Method(s): This was a retrospective cohort single centre study. Patients with IBD and perianal involvement confirmed by AR-EUS were included. Demographic, clinical, and ultrasonographic data were collected. Result(s): One hundred and thirteen AR-EUS were performed in 71 patients with IBD: 68 with Crohn's disease (CD), 1 with ulcerative colitis (UC) and two with unclassified colitis. Sixty-two per cent were female with a median age of 28.1 years (range 17-60). Fiftyfour percent of the patients had perianal disease at time of IBD diagnosis. CD localisation was ileal (L1) in 29.4%, colonic (L2) in 22.1% and ileocolonic (L3) in 48.5%. Upper gastrointestinal disease (L4) was present in 14.7% of the patients. CD had an inflammatory behaviour (B1p) in 70.6%, stricturing behaviour (B2p) in 19.1% and penetrating behaviour (B3p) in 10.3% of the cases. All the patients were treated with anti-TNF therapy (Infliximab: 70.4%, Adalimumab: 29.6%) and 56 received combination therapy (azathioprine: 75% and methotrexate: 25%). All the AR-EUS were performed without sedation. In CD, 87 perianal fistulas were found (43 intersphincteric; 26 transphincteric, seven suprasphincteric, 11 anovaginal); 43.7% fistulas were complex. Others ultrasonography findings were: 18 perianal abscesses (4 supralevator, 6 Ischiorectal, three Intersphincteric, 5 subcutaneous), 24 anal fissures (12 posterior, 11 anterior and 1 lateral), 13 internal sphincter lacerations, 19 anal ulcers and 5 external sphincter lacerations. Cicatricial changes and superior anorectal strictures were present in 15 and 4 patients, respectively. In the patient with UC, cicatricial changes and one lateral anal fissure were evident on AR-EUS. Ultrasonography findings in Unclassified Colitis patients were: one suprasphincteric fistula, one internal sphincter laceration and one anterior anal fissure. We found no significant association between the localisation or behaviour of CD and the type of fistula (p = 0.85 and p = 0.89, respectively). Conclusion(s): Suppurative complications were the main perianal finding in ano-rectal ultrasonography. In our series, we also found a high prevalence of echostructural changes, fissures and sphincteric lacerations, most due to prolonged and recurrent suppurative processes and surgical complications. We consider that anorectal ultrasonography has excellent tolerability and should be used in the assessment of perianal disease in all IBD patients.