[Last Modified: ]

February 2007
Answer to Case 198
The objects shown were eggs of the hepatic trematode, Dicrocoelium dentriticum.  Diagnostic features were:

• eggs that were ovoid in shape, brown color, and with an inconspicuous operculum.
• eggs within the size range for D. dentriticum.

Dicrocoelium dentriticum requires two intermediate hosts; the first intermediate host is one of several species of land snails and the second intermediate host is an ant.  The ants are ingested by herbivores such as sheep and cattle.  For humans to become infected, they would have to ingest metacercariae-infected ants.  Eating raw or undercooked liver from an infected animal can result in a spurious (i.e., false) infection.  This infection was most likely spurious based on the case history given.

For more information on dicrocoeliasis, please click here.