Fig. 3

Excised specimen and pathological findings. a Gross appearance of the excised specimen. The small intestinal mucosa was edematous and thickened, and a live Anisakis larva (arrow) was seen burrowing into the intestinal wall. A live Anisakis larva (arrow) is observed in the mesentery, along with severe circulatory disturbance and edematous of the intestinal wall. There was severe damage, but no obvious perforation was found in the intestinal wall. b, c Histopathology of the larva in the mesentery with hematoxylin and eosin (H&E) staining, b 2×, and (c) 10× magnification. The Anisakis larva was visually recognized with cuticular fragments. Eosinophil infiltration was not prevalent, but neutrophils were often phagocytosed, and granulation was observed. e–f Histopathology of the small intestine with H&E staining, and (d) 2× and (e, f) 10× magnification. The mucous membrane was extensively degraded and showed a ghost-like appearance. The muscle layer showed bleeding and severe circulation abnormalities