Dilated intercellular spaces: extending the reach of the endoscope.

Two manuscripts in this issue utilize quantitative methods to analyze the association between gastroesophageal reflux disease (GERD) and dilated intercellular spaces (DIS) evident on transmission electron microscopy of the esophageal epithelium. One study of 20 patients found that, irrespective of whether or not a pH study was positive, all GERD patients who had responded to proton pump inhibitors therapy had intercellular space measurements that were at least twice normal. The other study demonstrated that DIS resolved with effective GERD therapy in essentially every instance. Both studies suggest that DIS are an objective structural marker of endoscopy-negative reflux disease.