A critical assessment of the current status of non-erosive reflux disease.

Non-erosive reflux disease (NERD) has assumed increasing prominence in studies of gastroesophageal reflux disease (GERD), but it remains a challenge to define NERD precisely and to define its place in the investigation and treatment of GERD. Most simply, NERD may be defined as GERD in an individual who has no evidence of erosions at endoscopy. Unfortunately, the characteristic symptoms of GERD--heartburn and regurgitation--are insufficient to identify all GERD patients and, hence, the diagnosis of NERD is hampered by the lack of clear criteria for the symptomatic diagnosis of GERD. The diagnosis of NERD is hampered further by limited interobserver agreement on the endoscopic diagnosis of erosive esophagitis and by the fact that endoscopy is often performed soon after patients have discontinued therapy. Improvements in endoscopic technology will increase the likelihood of identifying small erosions or other reflux-related lesions; however, this will increase the proportion of patients considered to have erosive esophagitis without defining precisely what constitutes NERD. It is important to recognize that NERD is but one manifestation of GERD and that it, like other manifestations of GERD, is associated with a marked diminution in patients' quality of life. However, this recognition apart, there seems to be little practical benefit or understanding to be gained in clinical practice or clinical research from considering NERD as a distinct entity or from studying NERD patients in isolation. Advances in understanding the pathogenesis of GERD and its symptoms may be better served by categorizing GERD with respect to the spectrum of its histologic, functional, endoscopic and symptomatic manifestations rather than by studying NERD, a manifestation that is characterized solely by the absence of esophageal erosions.