Cestodes (tapeworms) Flashcards
What are the Cestodes? (6)
- Taenia saginata
- Taenia solium
- Diphyllobothrium latum
- Hymenolepsis nana
- Diphylidium caninum
- Echinococcus spp.
Taenia saginata:
-AKA
Beef tapeworm
Taenia saginata - Egg:
- size
- shape
- wall
- hooks
*Identical to what?
- 30-40 um
- Spherical
- Thick, radially striated wall
- 3 pairs of hooks
*Identical to T. solium
Taenia saginata:
-Scolex morphology
- 4 suckers
- Smooth surface
*Unarmed Rostellum
Taenia saginata:
-Proglottid morphology
- Longer than wide
- >13 lateral uterine branches
Taenia saginata:
- Geography
- Transmission
- Infection
- South/Central America (NOT in US)
- Beef (cysticerci)
- Small bowel infection by adult worm
T/F: T. saginata eggs are not infections.
True
*T. solium eggs are infectious, causes cysticercosis (larval form of disease in humans). Does NOT occur in T. saginata
Taenia solium:
-AKA
Pork Tapeworm
Taenia solium - Egg:
- size
- shape
- wall
- hooks
*Identical to what?
- 30-40 um
- Spherical
- Thick, radially striated wall
- 3 pairs of hooks
*Identical to T. saginata
Taenia solium:
-Scolex morphology
- 4 suckers
- Many tiny hooklets on surface
*Armed rostellum
Taenia solium:
-Proglottid morphology
- Longer than wide
- <13 lateral uterine branches
Taenia solium:
-Encysted larval form (cysticercosis) consist of..
- 1 cm cyst
- Invaginated scolex w/double row of hooklets*
*Acid-Fast/Birefringent
Taenia solium:
-Infections (2)
Intestinal infection
-Pork with cysticerci
Cystercercosis
- Ingestion of eggs shed in feces
- Pork ingestion not required
Diphyllobothrium latum:
-AKA
Fish Tapeworm
Diphyllobothrium latum - Egg Morphology:
- Size
- Shape
- Features (3)
*Similar to what?
- 60 um
- Oval
- Smooth shell
- Unshouldered Operculum
- Abopercular knob (small)
*Similar to P. westermani, which is larger and has a shouldered operculum
Diphyllobothrium latum - Diagnosis:
-Scolex
Resembles elongated Almond w/
-2 longitudinal sucking grooves
Diphyllobothrium latum - Diagnosis:
-Proglottid (2)
- Wider than long
- Coiled Uterus in shape of Rosette
Diphyllobothrium latum:
-Transmission
Freshwater fish
Diphyllobothrium latum - Diagnosis:
- Infection
- Complication
- Intestinal infection
- Vit. B12 deficiency
Hymenolepsis nana:
-AKA
Dwarf Tapeworm
Hymenolepsis nana - Egg Morphology. (3)
- Thin inner and outer shells
- 2 pairs of polar filaments in space between
- Embryo with hooklets (inner shell)
T/F: Hymenolepsis nana is relatively common in the US.
True
Hymenolepsis nana:
-Transmission (2)
- Ingestion of beetles
- Person-to-Person may occur
Diphylidium caninum:
-AKA
Double Pored Dog Tapeworm
Diphylidium caninum:
-Eggs (2)
- Similar to Hymenolepsis diminuta
- Occur in packets of 5-15 eggs
Diphylidium caninum:
-Proglottid
Double Genital Pore
-One on each side
Diphylidium caninum:
- Infection
- Transmission
Cats and Dogs
-Humans if ingestion of fleas
Echinococcus species:
-Cysts (2)
- Protoscoleces
- Hooklets
Echinococcus species:
- Transmission
- Definitive host
- Common where?
- Dog shit
- Dog
- Sheep and cattle raising areas (pastoral infection)