Parasitology
Lab-19 (F. hepatica + H. heterophyes)
1- Fasciola hepatica:
1- definitive host : man , sheep , cattle , ……..
2- intermediate host : snail lymnea
3- habitat : bile duct and biliary passages
4- infective stage to man : metacercaria (present in water vegitations)
5- diagnostic stage to man : egg ( stool examination )
6- route of infection : oral route ( eating uncooked watercress )
7- life cycle
غير هام
((adult in biliary passages egg in stool miracidium in snail
lymnea sporocyst – radia – cercaria cercaria leave snail encyst as metacercaria on
grass , watercress eaten uncooked by man penetrate intestinal wall , liver capsule
, biliary tree repeat the cycle ))
8- morphology :
Adult :
1- Leaf shape with branched intestine , testes , vitallariae
2- Large ( 2-3 cm in length )
3- Has shoulders ( shouldered appearance )
4- Anteriorly wider than posteriorly
5- Oral , ventral suckers
6- Ovary
7- Short convoluted uterus ( with eggs )
Cerearia :
1. Not - bifurcated tail
2. Has body
9 – Symptoms : pruritus - fever - Eosinophilia - urticara – epigastric pain – jaundice –
hepatomegaly - cholangitis - biliary obstruction
10 - Diagnosis :
stool examination ( see egg )
duodenal aspirate
skin test
Serological diagnosis
11 - Treatment : bithionol
2- Heterophyes heterophyes:
1- definitive host : man , cat , dog , animals that eat fish
2- intermediate host : first snail pirenella // second fish (mugil fish )
3- habitat : small intestine
4- infective stage to man : metacercaria (present on the scales , tail , gills , fins of fish)
5- diagnostic stage to man : egg fully empryonated ( stool examination )
6- route of infection : oral route ( eating uncooked fish )
7- life cycle
غير هام
((adult in small intestine egg in stool fully empryonated first
intermediate host snail sporocyst , radia , cercaria cercaria encyst to metacercaria on
scales , tail , gills , fins of mugil fish second intermediate host man eat raw fish
metacercaria escape become adult in week repeat the cycle )
8- morphology :
Adult :
1. Very small ( 1-2 mm )
2. Pyriform shape ( posterior end more rounded than anterior end )
3. Large oral sucker anteriorly
4. Large ventral sucker ( behind oral sucker )
5. Genital suckers ( behind and lateral to the ventral sucker)
6. 2 ovoid testes posteriorly
7. Ovary ( anterior to testes – oval shape – red color)
8. Polygonal Vitellarial glands ( posterior and lateral )
9. Intestine
10. Convoluted uterus ( with eggs )
Cerearia :
1. Not - bifurcated tail
2. Has body and head
9 – Symptoms : irritation - diarrhea - colicky pain - abdominal discomfort - tenderness -
eosinophilia
10 - Diagnosis :
stool examination ( see egg )
11 - Treatment : praziquantel