Dr. Souza trained at Howard University, Beth Israel Hospital (Boston), and the University of Maryland Medical Center. She is an Associate Professor of Medicine at the University of Texas Southwestern Medical Center and the Dallas VA Medical Center. Dr. Souza’s laboratory focuses on exploring molecular mechanisms through which the gastroesophageal reflux of acid and bile mediates the development of Barrett’s esophagus, the condition in which a metaplastic epithelium predisposed to malignancy replaces the squamous epithelium normally lining the distal esophagus. Her laboratory has demonstrated differences between esophageal squamous cells in patients who have gastroesophageal reflux disease (GERD) with and without Barrett’s esophagus in the signaling pathways that are activated by acid and bile salts. Those findings have formed the basis for her highly original perspective on why Barrett’s esophagus develops in only a minority of GERD patients. Her laboratory also focuses on how GERD might contribute to carcinogenesis in Barrett’s esophagus. Most recently, she has shown that gastroesophageal reflux elicits an immune-mediated injury (rather than a caustic chemical injury) as the initial pathogenetic event in reflux esophagitis, a finding that challenges long-held views on the development of that condition. In partnership with Dr. Stuart Jon Spechler, Dr. Souza combines traditional in vitro approaches to the study of disease with a novel, in vivo, translational approach involving perfusion of the human esophagus with acid or bile salts during endoscopic examination. As a result, Dr. Souza’s work has had substantial impact on the clinical management of patients with GERD and Barrett’s esophagus.