Two Cases of Stomach Granuloma Caused by Anisakis-like Larval Nematodes in Japan

Keizo Asami Department of Parasitology, School of Medicine, Keio University, Tokyo, Japan

Search for other papers by Keizo Asami in
Current site
Google Scholar
PubMed
Close
,
Tsutomu Watanuki Department of Parasitology, School of Medicine, Keio University, Tokyo, Japan

Search for other papers by Tsutomu Watanuki in
Current site
Google Scholar
PubMed
Close
,
Hazime Sakai Department of Parasitology, School of Medicine, Keio University, Tokyo, Japan

Search for other papers by Hazime Sakai in
Current site
Google Scholar
PubMed
Close
,
Hiroshi Imano Department of Parasitology, School of Medicine, Keio University, Tokyo, Japan

Search for other papers by Hiroshi Imano in
Current site
Google Scholar
PubMed
Close
, and
Ryozo Okamoto Department of Parasitology, School of Medicine, Keio University, Tokyo, Japan

Search for other papers by Ryozo Okamoto in
Current site
Google Scholar
PubMed
Close
Restricted access

Summary

Larval nematodes more than 2 centimeters in length were found in eosinophilic granulomas in the stomach of two patients suffering from acute abdominal symptoms. On the basis of morphological comparison with worms identified as immature Anisakis sp. from the sperm whale, the larva of one case was identified as Anisakis sp., and that of the other was identified as a different but closely related species. Striking features of the larvae were large Y-shaped lateral chords extending into the body cavity, and numerous, high columnar epithelial cells forming the wall of the intestine as well as a large gland-like organ along the esophagus and upper intestine.

The infections presumably were acquired by eating raw fish, a custom that is widespread among the Japanese. It is expected that similar cases may be found among Japanese patients presenting with acute abdominal symptoms.

Author Notes

Department of Pathology, School of Medicine, Tohoku University, Sendai, Japan.

Otaka Municipal Hospital, Otaka-machi, Fukushima, Japan.

Pathology Laboratory, Kitasato Institutes, Minato-ku, Tokyo, Japan.

Save