DILATED INTERCELLULAR SPACES - A MORPHOLOGICAL FEATURE OF ACID REFLUX-DAMAGED HUMAN ESOPHAGEAL EPITHELIUM

Background & Aims: Dilated intercellular spaces are a sign of epitheli al damage in acid-perfused rabbit esophagus, a change best identified by transmission electron microscopy. The aim of this study was to dete rmine if this change is also a feature of acid damage to human esophag eal epithelium. Methods: Endoscopic esophageal biopsy specimens from p atients with (n = 11) and without (n = 13) recurrent heartburn were ex amined using transmission electron microscopy. Of 11 patients with hea rtburn, 6 had erosive esophagitis and 5 had normal-appearing mucosa on endoscopy; 13 controls had no symptoms or signs of esophageal disease . Using a computer, intercellular space diameter was measured from tra nsmission electron microscopy photomicrographs of the specimen from ea ch patient. Results: Intercellular space diameter was significantly gr eater in specimens from patients with heartburn than those from contro ls; this was true irrespective of whether the patient had erosive or n onerosive disease. Space diameters of greater than or equal to 2.4 mu m were present in 8 of 11 patients with heartburn and in no controls. Conclusions: Dilated intercellular spaces are a feature of reflux dama ge to human esophageal epithelium. As a morphological marker of increa sed paracellular permeability, its presence in patients without endosc opic abnormalities may help explain their development of heartburn.