RESUMO
The aim of this study was to demonstrate changes in nature of mucin and production of acidic forms using PAS-Alcian blue stain at PH=2.5. Appearance of non-goblet metaplastic columnar cells of lower esophagus is considered as an early sign of Barrett'esophagus,"simultaneous in conjunction or before the appearance of goblet cells in patients with gastroesophageal reflux disease. Material and Forty four biopsy samples where taken from the squamo-columnar junction of patients with reflux associated columnar metaplasia of lower esophagus who referred to Shariati Hospital during 1378. All specimens were stained by Alcian blue-PAS at PH=2.5 to search for acidic mucin production in non-goblet metaplastic columnar cells of lower esophagus. Colonic mucosa specimen and the goblet cells from 9 case with overt intestinal metaplasia were used as external and internal positive controls and cardiac type columnar cells were considered as negative control for acidic mucin production. Eight out of 44 biopsy samples taken at squamo-columnar junction of patients with reflux associated columnar metaplasia in lower esophagus showed acidic mucin production in non-goblet metaplastic columnar cells. Alcian blue-PAS stain at PH=2.5 can demonstrate changes in nature of mucin content and reveals acidic mucin production in non-goblet metaplastic columnar cells of lower esophagus in some patients with gastroesophageal reflux disease. This finding can be considered as an early sign of "Barretts esophagus" before the appearance of goblet cells and can help in early detection of this premalignant lesion and as a result, better surveillance and follow up of the affected patients