ORIGINAL ARTICLE Prognostic Significance of Endoscopic Remission in Patients with Active Ulcerative Colitis Treated with Oral and Topical Mesalazine: A Prospective, Multicenter Study Gianmichele Meucci, MD,** Renato Fasoli, MD, † Simone Saibeni, MD, ‡ Daniela Valpiani, MD, § Renzo Gullotta, MD, k Enrico Colombo, MD, ¶ Renata D’Inca', MD,** Maddalena Terpin, MD, †† and Giovanni Lombardi, MD ‡‡ on Behalf of the IG-IBD Background: It has been recommended that the treatment of active ulcerative colitis (UC) should be continued until complete healing of endo- scopic lesions. However, the evidence supporting this recommendation is scanty. Aims of the present study were to assess the rate of patients with active UC who achieve clinical but not endoscopic remission after treatment with oral plus topical mesalazine and to compare the rate of relapse in patients with clinical/endoscopic remission and those with only clinical remission. Methods: Patients with active mild or moderate UC were eligible. All patients received mesalazine, 4 g/day orally and 2 g/day per rectum for 6 weeks. Those achieving clinical remission underwent colonoscopy: afterwards, all received maintenance treatment with oral mesalazine, 2 g/day orally for 1 year. Clinical remission was defined as normal frequency of bowel movements with formed stools, no abdominal pain, and no blood in the stools. Endoscopic remission was defined as normal-appearing mucosa or only mild redness and/or friability, without either ulcers or erosions. Results: In all, 81 patients were enrolled. Sixty-one (75%) achieved clinical remission. Endoscopic activity was still present in five (8%). The cumulative rate of relapse at 1 year was 23% in patients with clinical and endoscopic remission and 80% in patients with only clinical remission (P < 0.0001). Conclusions: Persistence of endoscopic activity is quite infrequent in patients with active UC achieving clinical remission after a 6-week treat- ment with oral plus topical mesalazine, but is a very strong predictor of early relapse. (Inflamm Bowel Dis 2011;000:000–000) Key Words: ulcerative colitis, mesalazine, endoscopic remission, mucosal healing U ntil recently, treatment of active ulcerative colitis (UC) has focused on improving symptoms and endo- scopic demonstration of mucosal healing has not been con- sidered a necessary endpoint in patients achieving clinical remission. 1,2 However, recent data suggest that concentrating exclusively on clinical outcome measures may not be adequate to achieve long-term treatment success. Indeed, achievement of endoscopic remission has been shown to correlate with a reduced risk of colectomy, 3,4 hospital admissions, and need for immunosuppressive treatments. 4 Recently, a panel of experts recommended that the pri- mary endpoint for therapeutic trials in patients with mildly to moderately active UC should be induction of remission, defined as complete symptom resolution and endoscopic healing. 5 Moreover, some experts at present recommend that the treatment of active UC should be continued until com- plete healing of endoscopic lesions is observed, 6 although no consensus exists on this topic. 2,7 In fact, the evidence supporting practical value associated with repeat endoscopy to monitor treatment progression is limited, and no consen- sus exists on how endoscopic remission should be assessed. 7 Mesalazine is currently the mainstay of treatment for patients with mild or moderate UC flares, 2 and combined treatment with oral and topical formulations appears to be Received for publication June 2, 2011; Accepted July 5, 2011. From the *Divisione di Gastroenterologia, Ospedale Valduce, Como, Italy, † Servizio di Gastroenterologia ed Endoscopia Digestiva – Unita ` Complessa di Medicina, Ospedale Costantino Cantu `, Abbiategrasso, Italy, ‡ Cattedra di Gastroenterologia, Universita ` degli Studi e IRCCS Policlinico, Milano, Italy, § Centro di Gastroenterologia ed Endoscopia Digestiva, Ospedale Morgagni Pierantoni, Forlı `, Italy, k Unita ` di Gastroenterologia ed Endoscopia Digestiva, Clinica San Carlo, Paderno Dugnano, Italy, ¶ Unita ` Operativa di Medicina Generale ad Indirizzo Gastroenterologico, Azienda Ospedaliera G. Salvini, Garbagnate Milanese, Italy, ** Dipartimento di Scienze Chirurgiche e Gastroenterologiche, Universita ` di Padova, Padova, Italy, †† UOC Gastroenterologia ed Endoscopia Digestiva, Azienda Ospedaliera ‘‘Ospedale Civile di Legnano,’’ Legnano, Italy, ‡‡ UOC Gastroenterologia ed Endoscopia Digestiva, Ospedale ‘‘Casa Sollievo della Sofferenza’’ IRCCS, San Giovanni Rotondo, Italy. Reprints and current address: Gianmichele Meucci, Division of Gastroenterology, Ospedale San Giuseppe, Via San Vittore 12, 20123 Milano, Italy (e-mail: g.meucci@teletu.it). Copyright V C 2011 Crohn’s & Colitis Foundation of America, Inc. DOI 10.1002/ibd.21838 Published online in Wiley Online Library (wileyonlinelibrary.com). Inflamm Bowel Dis 1