It is classified as moderate when congested areas are present together with edema which reduces the caliber of the bulb slightly and when the first portion does not fully distend with insufflation. It is considered to be severe when congested areas are present together with edema which reduces the caliber of the bulb so severely that the size and elasticity of the bulb become difficult to determine visually, but there is no presence of ulceration or erosion. Erosive duodenitis is defined by the presence of parietal defect in the mucosa which are less than one millimeter deep and less than one millimeter in diameter, and by variables related to lesion location.
La primera se clasifica en grado leve presencia de zonas de congestión, moderado presencia de congestión y edema que reduce parcialmente el calibre del bulbo y la primera porción que no se distienden completamente a la insuflación y severo congestión y edema que reducen severamente el calibre y distensibilidad del bulbo y dificultan la visualización, sin presencia de ulceración ni erosión; la segunda, duodenitis erosiva, definida por la presencia de soluciones de continuidad de la mucosa menores a un milímetro de profundidad, de extensión y localización variables.