F.buski

the Medical Parasitology of Fasciolopsis buski of BioMedical Science

1. TREMATODA TREMATODA
Fasciolopsis buskiFasciolopsis buski

2. IntroductionIntroduction
Fasciolopsis buskiFasciolopsis buski lives in the small intestine of lives in the small intestine of
humans and pigs. humans and pigs.
Measuring up to 80 mm in lengthMeasuring up to 80 mm in length
largest trematodes found in humanslargest trematodes found in humans
Geographic Distribution:Geographic Distribution:
Asia and the Indian subcontinent, especially in Asia and the Indian subcontinent, especially in
areas where humans raise pigs and consume areas where humans raise pigs and consume
freshwater plants.freshwater plants.
As with many other parasites that infect humans, As with many other parasites that infect humans,
pigs serve as a reservoir hostpigs serve as a reservoir host
Can cause FascioslopsiasisCan cause Fascioslopsiasis

3. MORPHOLOGY : ADULT MORPHOLOGY : ADULT
The adult flukes range in size: 20 to 75 mm by 8 to The adult flukes range in size: 20 to 75 mm by 8 to
20 mm. 20 mm.
No cephalic cone, acetabulum larger than oral No cephalic cone, acetabulum larger than oral
sucker. sucker.
Testis posterior & branched.Testis posterior & branched.
Attach themselves to the tissues of the small Attach themselves to the tissues of the small
intestine of the host by means of ventral suckers; intestine of the host by means of ventral suckers;
the sites of attachment may later ulcerate and form the sites of attachment may later ulcerate and form
abscesses.abscesses.

5. The adult flukes range in size: 20 to 75 mm by 8 to 20 mm.
Fasciolopsis Buski adult;
approximate length = 50 mm

6. Typical gymnocephalus cercaria of a fascioliid.  This is a
ventral view showing the spherical acetabulum framed by the
two branches of the caeca.  This Fasciolopsis buski cercaria
is indistinguishable from the cercaria of Fasciola hepatica. 
100x

7. This photo is to compare the sizes of Fasciolopsis buski (left) and
Fasciola hepatica (right), 2x.

8. Egg is practically indistinguishable from those of Egg is practically indistinguishable from those of
Fasciola hepaticaFasciola hepatica. .
The eggs are ellipsoidal, with a thin shell, and a The eggs are ellipsoidal, with a thin shell, and a
usually small, indistinct operculum, range in size: usually small, indistinct operculum, range in size:
130 to 159 µm by 78 to 98 µm.130 to 159 µm by 78 to 98 µm.
MORPHOLOGY : EGGMORPHOLOGY : EGG

10. Life cycleLife cycle

11. Cont..Cont..
Immature eggs are discharged into the intestine and stool.Immature eggs are discharged into the intestine and stool.
Eggs become embryonated in water , eggs release miracidia , Eggs become embryonated in water , eggs release miracidia ,
which invade a suitable snail intermediate host. which invade a suitable snail intermediate host.
In the snail the parasites undergo several developmental stages In the snail the parasites undergo several developmental stages
(sporocysts, rediae, and cercariae ). (sporocysts, rediae, and cercariae ).
The cercariae are released from the snail and encyst as The cercariae are released from the snail and encyst as
metacercariae on aquatic plants. metacercariae on aquatic plants.
The mammalian hosts become infected by ingesting The mammalian hosts become infected by ingesting
metacercariae on the aquatic plants. metacercariae on the aquatic plants.
After ingestion, the metacercariae excyst in the duodenum and After ingestion, the metacercariae excyst in the duodenum and
attach to the intestinal wall.attach to the intestinal wall.
There they develop into adult flukes (20 to 75 mm by 8 to 20 mm) There they develop into adult flukes (20 to 75 mm by 8 to 20 mm)
in approximately 3 months, attached to the intestinal wall of the in approximately 3 months, attached to the intestinal wall of the
mammalian hosts (humans and pigs).mammalian hosts (humans and pigs).
The adults have a life span of about one year.The adults have a life span of about one year.

12. Pathogenicity & SymptomPathogenicity & Symptom
Most infections are light and asymptomatic. Most infections are light and asymptomatic.
In heavier infections, symptoms include diarrhea, In heavier infections, symptoms include diarrhea,
abdominal pain, fever, ascites, and intestinal abdominal pain, fever, ascites, and intestinal
obstruction. obstruction.
Chronic infections with this parasite lead to Chronic infections with this parasite lead to
inflammation, ulceration, hemorrhage, and inflammation, ulceration, hemorrhage, and
abscesses of the small intestine, and these can abscesses of the small intestine, and these can
ultimately lead to the host's death. ultimately lead to the host's death.

13. Laboratory Diagnosis Laboratory Diagnosis
Microscopic identification of eggs, or more rarely Microscopic identification of eggs, or more rarely
of the adult flukes, in the stool or vomitus is the of the adult flukes, in the stool or vomitus is the
basis of specific diagnosis. basis of specific diagnosis.
The eggs are indistinguishable from those of The eggs are indistinguishable from those of
Fasciola hepaticaFasciola hepatica..
TreatmentTreatment : Praziquantel : Praziquantel

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