Fig. 4

The microscopic findings. a There is a volcanic eruption image, in which the pseudomembrane component is ejected into the intestinal lumen at the mucosal defect. The pseudomembrane histologically consists of fibrin, mucus, neutrophils, and nuclear debris. b The expanded frame of the crypt remains on the mucosa of the pseudomembrane attachment site, and the dropped-out epithelial cells are seen in the lumen