Refractory chronic diarrhea complicated with optic neuritis in a young woman: A case report

Figure 2 Histopathological analysis. A and B: The epithelium of the mucosal portion of the descending duodenum had sloughed off, the subepithelial collagen band was thickened, the mucosal villi were significantly atrophied (arrow in A), and there was plasma cell infiltration throughout the mucosal layer. Degeneration in the local mucosal muscle was suspected; C: Masson staining was positive, indicating that the subepithelial substances were collagen fibers (arrow).