Prevalence of intestinal metaplasia according to the length of the specialized columnar epithelium lining the distal esophagus in patients with gastroesophageal reflux.

The diagnosis of Barrett's esophagus is based on the presence of intestinal metaplasia (IM) at the distal esophagus. The aim of this study was to determine the prevalence of IM in patients with symptoms of gastroesophageal reflux in whom endoscopically a segment of distal esophagus was covered by columnar epithelium (CE). In a prospective, descriptive and transversal study, 492 patients (33%) from 1480 patients with gastroesophageal reflux, in whom endoscopic evaluation demonstrated the presence of a short-segment CE measuring less than 3 cm or a long-segment CE measuring more than 3 cm, were evaluated. From each patient, several biopsy specimens were taken, which were stained with hematoxylin-eosin and Alcian blue pH 2.5. Out of 492 cases, 421 patients (86%) presented with a short-segment CE and 71 patients (14%) had a long-segment CE. Among these 71 cases, 38 had a 3-6 cm-length CE, 21 patients had a 6.1-10 cm-length CE and 12 patients had CE more than 10.1 cm in length. Endoscopic short-segment CE was six times more frequent than long-segment CE. The prevalence of IM was 35% among patients with short-segment CE and increased progressively according to the length of CE, being 100% in patients with > 10 cm in length. Therefore, true short-segment BE was three times more frequent during endoscopic studies than long-segment BE. Dysplasia in the metaplastic epithelium also increased parallel to the length of the CE. True BE (presence of IM at the columnar epithelium lining the distal esophagus), was present in 13.6% of all patients with symptoms of gastroesophageal reflux submitted to endoscopic evaluation. Short-segment BE is three times more frequent than long-segment BE, and endoscopic and bioptic evaluation is fundamental in all cases with gastroesophageal reflux who exhibit some segment of the distal esophagus lined by columnar epithelium, even if it is > or = 1 cm long.