In patients with GERD, there is a proportion of patients with negative endoscopy, which we call non-erosive reflux disease (NERD). Western literature reports that NERD accounts for 50% to 70% of GERD patients. The natural history of NERD It is believed that GERD is a spectrum of disease, with NERD, reflux esophagitis and barrett’s esophagus in descending order of severity. Is this really the case? Does NERD develop into a more serious disease over time? The answer is no. Isolauri et al. conducted a long-term follow-up of GERD patients over a period of 17-22 years. At the end of an average of 19 years of follow-up, none of the 50 GERD patients with grades 0 to II had progressed to grades III or IV according to the severity of the disease. On the other hand, do the symptoms of NERD patients indicate the severity of esophagitis? In a study by Venables et al, of 993 patients with GERD, 667 (68%) had NERD and 316 (32%) had reflux esophagitis (RE), and the proportion of patients with severe symptoms was exactly the same in both groups according to the severity of heartburn symptoms, so the symptoms of patients with NERD did not indicate the severity of esophagitis. It is believed that NERD and reflux esophagitis are two different diseases with different pathogenesis, and there are different subtypes of NERD patients, namely acid reflux, non-acid reflux and functional heartburn. The widening of the esophageal epithelial gap plays an important role in the pathophysiological pathogenesis of NERD. New diagnostic techniques In addition to traditional methods such as endoscopy and 24-hour esophageal pH monitoring, some new esophageal tests can help to differentiate between erosive and non-erosive GERD. Esophageal capsule endoscopy This is an accurate, convenient, safe and well-tolerated method of screening for esophageal disease, and patients do not require sedation. While the small bowel capsule endoscope can take 2 pictures per second, the capsule endoscope passes through the esophagus at a faster rate. By using a special technique, the esophageal capsule endoscope can take 7 pictures per second, and since it can take pictures in both directions, 14 pictures per second can be obtained. BravoTM pH System Traditional 24-hour transnasal catheter pH monitoring methods, while providing valuable information to physicians, are limited in their use due to increased patient discomfort. The new catheterless BravoTM pH system can successfully monitor a patient’s intraesophageal gastric acidity. The BravoTM pH capsule probe is inserted through a transfer catheter and secured to the esophageal wall, then the catheter is removed and the capsule attached to the esophageal wall delivers the measured pH to an external receiver device for 48 hours, with the capsule probe melting naturally after 2 to 7 days. Portable combined impedance-pH measurement This is a dual-mode reflux test that measures acid reflux and non-acid reflux, observes acid reflux and heartburn in relation to non-acid reflux episodes, observes the movement of the food mass, and is not dependent on radiation. A subtype of NERD, non-acid reflux, is characterized by normal esophageal pH and abnormal impedance. Treatment Proton pump inhibitors remain the treatment of choice for NERD, but they are not as effective in symptom control as they are in erosive esophagitis. Further staging of NERD patients to identify those with non-acid reflux will allow for more targeted treatment. In addition, baclofen can be used for transient relaxation of the lower esophageal sphincter, but it is difficult to accept clinically because of some side effects. In addition, it is important to tell patients that whether it is NERD, RE or Barrett’s esophagus, if there is a recurrence after the symptoms disappear, the disease will remain the same, for example, NERD will remain NERD after a recurrence and RE will remain RE after a recurrence, just like a person’s ethnicity will not change.