CESTODES
EGG
LARVA
ADULT WORM
LIFE CYCLE
INFECTIVE
FORM:
CLINICAL FEATURES
LAB DIAGNOSIS:
Key takeaways:
Pseudophyllidean:
Diphyllobothrium
latum
(fish tapeworm)
(broad tapeworm)
• operculated, has
knob on other end
• passed as
unembryonated
egg
3 larval stages:
L1 = coracidium
(ciliated)
L2 = procercoid
L3 = plerocercoid
(encysted)
• Scolex = spoon
shaped, with 2-
slit longitudinal
groove (bothria)
• Strobila =
bilobed ovary,
rosette-like
uterus,
3 Hosts:
Diphyllobothriasis
• cause mechanical
obstruction
• cause pernicious
anemia
(bothriocephalus
anemia)
• cause megaloblastic
anemia
These anemia is
caused by vit. B12
deficiency.
Stool microscopy:
Detection of
eggs/proglottids
Serodiagnosis:
coproantigen
Common name: Fish
tapeworm
• longest, broad, and
largest tapeworm
infecting humans
• embryogenesis &
hatching to L1
happens in the
environment
• feeds on Vit. B12
• has paratenic life
cycle
DH = Man
➔ Plerocercoid
larva
IH #1 = Copepods,
crustaceans
➔ Coracidium
IH #2 = Freshwater
fish
➔ Procercoid
larva
Spirometra spp.
Same as D. latum
Same as D. latum:
Only that its name of
plerocercoid larva
(L3) = SPARGANUM
Same as D.
latum
Same as D. latum
with 3 hosts:
Same as D. latum
Sparganosis
-caused by ectopic
infection of sparganum.
-sparganum penetrates
subcutaneous tissue,
forming nodules.
Diagnosis only possible
after surgical removal of
nodules
•definitive treatment is
surgical removal of
nodules
• once the sparganum
invades the
subcutaneous tissue
and form nodules, it
will no longer develop
into adult worm
DH= dog, cat
IH#1 = copepods,
cyclops
IH#2 = snakes, frogs,
fishes
• man is accidental
host and dead end
Cyclophyllidean
Taenia saginata
(Beef tapeworm)
Embryonated egg,
striated
embryophore
Cysticercus bovis
•Scolex=
rostellum and
hooks ABSENT
• Longer than T.
solium
• Has (1) genital
pore/ vaginal
sphincter
2 HOSTS:
DH= Man
IH = Cow/cattle
Cysticercus bovis
Intestinal taeniasis
Stool microscopy:
Demonstration of
eggs/proglottids/scolex
Coproantigen
Definitive diagnosis of
unarmed scolex
Taenia solium
(Pork tapeworm)
Embryonated egg,
striated
embryophore
Cysticercus
cellulosae
•Scolex =
rostellum and
hooks PRESENT
• Shorter than T.
saginata
2 HOSTS:
DH= Man
IH = Pigs
Cysticercus
cellulosae
& embryonated
egg (for
cysticercosis)
Intestinal taeniasis
and
Cysticercosis
For intestinal taeniasis:
• Stool microscopy:
demonstration of
eggs/proglottids/scolex
For cysticercosis:
• Biopsy = definitive method
Treatment for
intestinal taeniasis:
praziquantel
For cysticercosis:
excision is the best
method
