Abstract
Between 1994 and 1999, we had experienced 17 cases of gastric anisakiasis at Tako Central Hospital, Which is located in the north eastern part of Chiba Prefecture. Seven patients (41.2%) developed gastric anisakiasis after eating raw sardines and 2 (11.8%) after eating raw bonito. The disease was prevalent between December and May, i.e., the period when sardines abound. Fourteen patients (82.4%) developed symptoms at night and upper abdominal pain was the commonest symptom (16 patients) . Twelve patients (70.6%) visited the hospital within 12 hours since the onset of symptoms. However, three patients waited 2 days or longer to see the doctor. Gastric anisakiasis usually presented as upper abdominal pain of sudden onset and anamnesis was most important for a correct diagnosis of the infection because it does not follow a typical pattern. As for the number of Anisakis larvae found at the gastroscopy, there was one larva in 15 patients (88.2%) , two larvae in one and four larvae in one patient. The gastric mucosa at the site of the larvae penetrated the tissues most frequently presented edema, erosion and redness. The mucosa often showed erosion, spotty coagulation and superficial gastritis in other areas. These results indicate that close gastroscopic examination of the gastric mucosa, especially at the corpus, should be done when a patient is suspected of having anisakiasis.
