• gastrointestinal infections
• gastroenterology
• general medicine (see Internal Medicine)
• infectious diseases
• epidemiology
• tropical medicine

A 28-year-old man with an acute history of abdominal pain presented to our emergency department complaining of tape-like structure protruding from his anus (figure 1). There was no history of fever, rebound tenderness or weight loss. He had no previous significant medical problems and denied any recent travel outside Japan. However, he also reported that he regularly ate raw salmon sushi. The complete blood examination, including an eosinophil count and blood chemistry, was unremarkable. The vitamin B12 level was not checked in the emergency …