Eleven newly diagnosed patients and one patient with pemphigus vulgaris who relapsed underwent endoscopy of the upper gastrointestinal tract. Three patients had blisters or erosions and two had longitudinal lines of erythema in the esophageal mucosa. In four patients histopathologic examination showed findings of pemphigus vulgaris but direct immunofluorescence was positive in all patients. This study demonstrates that the immunopathologic disturbance in pemphigus vulgaris involves the entire length of the esophagus, although only some patients have clinical or histologic involvement. To the best of our knowledge this is the first histopathologic and direct immunofluorescence study of esophageal involvement in patients with untreated pemphigus vulgaris.