Geographic distribution. China, Korea, Japan, Hong Kong, South America, etc.
Infection rate. E. pacreaticum is a common parasite of pancreatic (or rarely bile) ducts of herbivorous mammals, i.e., cattle, sheeps, goats, monkeys, and camels.
Life cycle. The adult flukes live in the pancreatic passages of the herbivores. Eggs are passed in the feces and ingested by land snail, which is the first intermediate host(snail). The cercariae develop into infective metacercariae only if ingested by grasshoppers, the second intermediate host. The life cycle is completed when the infected insects are eaten by grazing herbivores. The metacercariae excyst and migrate to the pancreatic passage, where they develop into adults. Humans become infected when they accidentally swallow infected grasshoppers.
Morphology. The parasite (10∼18 x 5∼9 mm in size) is broad, flat, and oval to fusiform. The suckers are large, the oral sucker is larger than the ventral sucker. The eggs (50∼80 x 35∼40 ㎛) are embryonated in the uterus.
Pathology and clinical symptoms. Eurytremiasis usually causes mild symptoms. Heavy infections, however, may be marked by gastrointestinal disturbances, including abdominal distress, flatulence, vomiting, diarrhea or constipation. Jandice, an enlarged liver, and systemic symptoms are reported. Eosinophilia is rare.
Diagnosis. Diagnosis is made by finding the characteristic eggs in feces. Spurious infection must be ruled out by repeated examination. Definitive diagnosis can be made by recovery of adult flukes at surgery or autopsy.
Prevention. Human infections are generally accidental.
Comments. Eggs of the Dicrocoelium dendriticum and E. pancreatum is almost indistinguishable.
Adult worm of Eurytrema pancreaticum.
Tai Soon Yong
Eurytrema pancreaticum : from pancreas of cattle, Acetocarmine stain, X40
Yong Suk Ryang
Eurytrema pancreaticum collected from a cattle.Semichon's acetocarmine stained.