Anisakiasis is infection with larvae of worms of the genus Anisakis and related genera such as Pseudoterranova. Infection is acquired by eating raw or poorly cooked saltwater fish; larvae burrow into the mucosa of the GI tract, causing discomfort.
(See also Approach to Parasitic Infections.)
Anisakis is a parasite that resides in the GI tract of marine mammals. Excreted eggs hatch into free-swimming larvae, which are ingested by fish and squid; human infection is acquired by ingestion of these intermediate hosts in a raw or undercooked state. Thus, infection is particularly common in locations such as Japan and cultures in which raw fish is traditionally consumed. Larvae burrow into the stomach and small bowel of humans.
Symptoms of anisakiasis typically include abdominal pain, nausea, and vomiting within hours of ingesting the larvae. In the small intestine, the infection may result in an inflammatory mass, and symptoms resembling Crohn disease may develop 1 to 2 wk later.
Anisakiasis typically resolves spontaneously after several weeks; rarely, it persists for months.
Humans acquire Anisakis when they consume the intermediate hosts (fish or squid) that are raw or undercooked; thus, anisakiasis is common in Japan and other cultures where raw fish is traditionally consumed.
Anisakiasis typically causes abdominal pain, nausea, and vomiting within hours of ingesting the larvae; an inflammatory mass may form in the small intestine and symptoms may resemble Crohn disease.
Anisakiasis typically resolves spontaneously after several weeks.
Do upper endoscopy to diagnose anisakiasis.
Endoscopic removal of the larvae is curative.