anisakiasis

Introduction

Gastrointestinal infection caused by accidental ingestion of uncooked saltwater fish containing nematodes of the family Anisakidae.

Etiology

• Anisakis simplex
• Pseudoterranova decipiens

Epidemiology

• most cases in Japan, Netherlands & Chile
• sushi, pickled green herring & ceviche respectively, implicated
• larvae killed by cooking to 60 degrees C or freezing at -20 degrees C for 3 days
• larvae not killed by smoking, marinating, or salting

Pathology

• larvae may pentrate mucosa of stomach
• larvae may enter small bowel & penerate mucosa eliciting eosinophilic granulomatous response

Clinical manifestations

• violent upper abdominal pain may occur within hours of ingestion
  • nausea & occasionally vomiting
  • may mimick acute abdomen
• symptoms may appear 1-2 weeks after ingestion
  • intermittent abdominal pain
  • diarrhea
  • nausea
  • fever
  • may resemble Crohn's disease

Laboratory

• direct visualization with upper endoscopy
• outlining of worms by radiocontrast studies
• histopathology of biopsied material
• eggs not found in stool since larvae do not mature in humans
• Anisakis IgE in serum

Differential diagnosis

• Crohn's disease

More general terms

• helminth infection

Additional terms

• Anisakidae