[Ulcerative colitis with segmental involvement].

Introduction: Ulcerative colitis is a chronic inflammatory disease affecting areas of the colon or the full length. From the endoscopic point of view, ulcerative colitis presents lesions that stretch continuously from the rectum to variable colon segments, a characteristic that is of great value when distinguishing it from Crohn's disease. Continuous involvement, without healthy patches, justifies ending endoscopic exploration once the distal end of the lesion has been reached.

Objective: To retrospectively study the frequency of segmental lesions in the colonoscopies performed in patients with ulcerative colitis.

Methods: Diagnosis of ulcerative colitis and proctitis was established by clinical, endoscopic, histologic, analytical, and radiological criteria. The indication and number of endoscopies was made on the basis of the clinical criteria of diagnosis, acute episodes, refractoriness or dysplasia screening. The extent of the examination also depended on clinical criteria: the severity of the episode, tolerance to colonoscopy or the degree of cleansing.

Results: A total of 155 coloscopies were performed. In 113 colonoscopies (73%) the distal end of the lesion was reached and in 70 (45%) the cecum was reached. Of the 80 patients, 27 (33%) presented ulcerative proctitis at diagnosis. Nine of the 80 patients (11.3%) biopsies were performed in healthy colonic patches, which confirmed histological normality. Six of the 9 patients were receiving no treatment. In all patients except two, the cecum was reached in one or more of the colonoscopies. The distribution of the segmental lesions varied but these were mainly found in the periappendicular region and in the cecum in 6 of the 7 patients in whom the cecum was reached. Of the 80 patients, endoscopic evidence of rectal sparing was found in 5 (6.3%); of these, 4 were receiving systemic or topical treatment. Histological analysis confirmed the absence of inflammatory lesions in these patients. The only patient who was not receiving treatment presented microscopic lesions compatible with ulcerative colitis.

Conclusions: Endoscopic segmental lesions in ulcerative colitis were present in 11.3% of patients. Segmental lesions were most frequently found in the cecum and periappendicular region. Endoscopic and histologic evidence of rectal sparing may be the result of systemic or topical treatment.