Specialized intestinal epithelium occurs more frequently at the gastroesoph
ageal junction than previously anticipated. It can occur either within tong
ues of mucosa (short segment Barrett's) or just beneath a normal z-line (in
testinal metaplasia at the gastroesophageal junction). Whether the etiopath
ogenesis and the natural history of these two conditions are the same is as
get unclear. The role of gastroesophageal reflux disease (GERD), Helicobac
ter pylori, and inflammation at the gastroesophageal junction in the pathog
enesis of short segment Barrett's and intestinal metaplasia at the gastroes
ophageal junction needs to be carefully documented. Intestinal metaplasia a
t the gastroesophageal junction, short segment Barrett's, and Barrett's may
represent a continuum of the same disease process. Recent evidence suggest
s, however, that short segment Barrett's shares similar characteristics wit
h Barrett's but may be distinct from intestinal metaplasia at the gastroeso
phageal junction. It is conceivable that short segment Barrett's may remain
steady or even regress if and when the noxious influence wanes but, with c
ontinuing stimulation, short segment Barrett's may lengthen further to beco
me what we observe to be Barrett's, If correct, endogenous or exogenous fac
tors that induce progression need to be identified. Acid and bile reflux an
d H. pylori are possible candidates acting either singly or synergistically
, Finally, the true neoplastic potential of short segment Barrett's needs c
larification. (C) 1999 by Am. Cell. of Gastroenterology.