Routine histological examination: (A) Control: normal esophageal mucosa, no inflammatory cells, epithelium basal layer thickness is often less than 15% of the total thickness. (B) Non-erosive reflux diseases: no inflammatory cells in squamous mucosa, mild basal cell hyperplasia, mild papillae elongation (C) NERD + Gastritis: few neutrophils or eosinophils in squamous mucosa. (D) Reflux esophagitis: numerous neutrophils or eosinophils (5-15/HPF) in squamous mucosa, elongated papillae, more than 30% of epithelial thickness is basal cells. (Magnification: 40x,20x) with hematoxylin-eosin staining.