糜烂Erosion · 前胃 · 消化系统 · NTP ntp-0217

Comment：
An erosion ( Figure 1 and Figure 2 ) is defined as the loss of superficial epithelial layers of the mucosa, whereas an ulcer is the loss of all epithelial cell layers, extending through to the submucosa. Erosions can occur anywhere in the gastrointestinal tract, but the forestomach is a relatively common location. Erosions often occur in areas of preexisting epithelial hyperplasia. Alternatively, the presence of an erosion can induce epithelial cell proliferation (as a healing response), which can result in epithelial hyperplasia. Inflammation is common in tissues around erosions. Erosion of the forestomach can be spontaneous, secondary to the gavage procedure, or treatment related (especially when the test article is an irritant), but in many cases, the exact cause of erosions is not known.

Recommendation：
Erosion of the forestomach should be diagnosed whenever present. Erosions should be graded based on the extent, number, and depth of the lesions. Secondary lesions, such as edema, inflammation, and hyperplasia of the adjacent epithelium, should not be diagnosed separately unless they are prominent components of the lesion or they are considered a primary lesion (e.g., the hyperplasia occurred prior to the erosion). Necrosis of the epithelium is diagnosed instead of erosion if the necrotic epithelium is still present and attached to the underlying lamina propria (see Stomach, Forestomach - Necrosis ). Related Links: Stomach, Forestomach - Necrosis