No parietal cell hypertrophy of the metaplastic corpus mucosa in the distal esophagus under PPI treatment.

When biopsies obtained from short tongues of columnar epithelium in the distal esophagus show only corpus or cardia-corpus transitional mucosa, it remains uncertain whether we are dealing with columnar epithelium metaplasia or a sampling error. In 50 patients with gastro-esophageal reflux disease receiving proton pump inhibitor (PPI) with such tongues of columnar epithelium, we noted that under this treatment, PPI-typical hypertrophy of the parietal cells in the corpus can be found, but not in the corpus or cardia/corpus transitional mucosa in biopsy material obtained from tongues of columnar epithelium in the distal esophagus. These observations may by an indication that in short segments of columnar epithelium corpus, mucosa with no PPI-induced hyperplasia of the parietal cells may be interpreted as metaplastic mucosa.