INTESTINAL (Helminths) AND LIVER PARASITES
TREMATODA Order: Echinostomata

FASCIOLA HEPATICA

fh1-ic

F.hepatica: life cycle.

F.hepatica infection is found in rural areas of temperate
and tropical regions, related to cattle herding.
High prevalence is described in Europe and Latin America.

fh2-ic	fh2a-ic

fh2: F.hepatica, adult worm, macroscopic examination:
adults measure 2-5 cm by 8-13 mm, are flat, oval in shape with a cephalic
cone containing the oral sucker.
The adults live in biliary ducts for up to 10 years. 

fh2a: Fasciola hepatica, living adult in bile duct of sheep.

fh3-ic

F.hepatica, adult worm, macroscopic examination:
higher magnification: particular of the cephalic cone with the oral sucker.

fh4-ic

F.hepatica, adult worm, liver biopsy: after excistation
in the small intestine, metacercariae penetrate the intestinal wall
and the Glisson capsule, cross the liver parenchima to the bile ducts.
Eggs can be found in faeces 3-4 months after penetration.

fh5-ic

F.hepatica, adult worm: the diagnosis is confirmed by the presence of eggs in faeces.
Repeated examinations and concentration techniques are recommended.
Serology is useful when the clinical picture is compatible and eggs are not found.

fh6-ic

F.hepatica, egg: eggs measure 140 by 80 µm and are operculated.
The colour is yellow to brown. (Formol-ether concentration).

fh7-ic

F.hepatica, egg: the opercular end is more visible at higher magnification;
sometimes it can present a shell irregularity.

fh8-ic

F.hepatica, egg: the operculum can be open.
Eggs are unembrionated and contain a granular material.

fh9-ic

F.hepatica, egg: the open operculum at higher magnification.

fh10-ic

Fasciola hepatica: although direct diagnosis by observation of eggs in faecal smears
it the reference method, indirect diagnostic tests such as IF may allow diagnosis
when direct observation is negative.
Immunodiagnosis by indirect immunofluorescence.
Antigen: frozen sections of Fasciola hepatica.

 

INT...(Helminths)LIVER....