Cestode

  1. Cestodes

    What are cestodes?
    They are tapeworms which live attached to the mucosa of the small intestine.

    *Absorb protein & carbs to reproduce

    • Scolex is organ of attachment
    • Proglottids is attached to scolex
    • Stobila is the chain of proglottids
  2. Diphyllobothrium latum - d. latum

    Life Cycle
    • Human eats under-cooked fish
    • scolex, proglottis, & adults harbor in small intestine.
    • human passes unembronated egg
    • embryonated eggs infect crustacean which
    • then infect fish.
  3. D. latum

    Who is the definitive host & intermediate host
    Definitive:humans, dogs, foxes, cats, seals, etc. that might eat fish

    Intermediate: copepod(crustacean), fish, pike or salmon are common
  4. D. latum

    Location & Disease
    Europe, Russia,Israel,US in heavy fish eating regions. ie. Great Lakes Region

    sparganosis
    (larval infection), anemia (B12), obstruction, diarrhea, abd pain
  5. D. latum

    Diagnosis
    Eggs or proglottids in stool
  6. Cestode: Taenia species - 


    Life Cycle - same for saginata and solium
    • 1) Animal (Beef/Pork) eat infected vegetation
    • 2) Oncospheres hatch & invade intestinal wall then migrated to striated muscles. 
    • 3) Develop into cysticerci.
    • 4) Humans eat undercooked meat.
    • In 2 mos time, cysticerus mature to adult tapeworm.
    • 5) Adults attache to small intestine & produce proglottids.
    • 6) Proglottids leave via stool with eggs.

    *In Solium: if eggs ingested, oncosphere hatch and move to muscle of man instead of pig.
  7. T. saginata - Beef Tapeworm

    Location/Disease
    Worldwide - rare in US

    Disease: Taeniasis

    Few symptoms: discomfort, proglottids crawling out of anus
  8. T. saginata

    Worm Identification
    • Scolex: 4 Suckers, NO hooks
    • Proglottids: 15-20 lateral uterine branches

    Egg: 35-45um with Radial striations
  9. T. solium - Pork Tapeworm

    Location/Disease
    Worldwide - rare in US

    Disease: Taeniasis or cysticercosis

    cysticercosis must be surgically removed
  10. T. saginata 

    What is the intermediate host
    Cow - beef
  11. T. solium

    What is intermediate host
    Pig - pork
  12. T. solium

    Worm Identification
    • Scolex: 4 Suckers with a central crown of HOOKS. 
    • Proglottids: 7-13 uterine branches (usually 9)

    Egg: Identical to T. saginata
  13. T. saginata & T. solium

    Identification
    Eggs are identical - treatment same for both. 

    • Count uterine branches
    • Solium has hooks too.
  14. Cestode: Hymenolepis nana - H. nana

    is also known as:
    dwarf tapeworm
  15. H. nana

    Location / clinical disease
    • Worldwide - common in children
    • Spread person to person via eggs

    • Autoinfection possible
    • hymenolepis - can by asymptomatic, symptoms may include headache dizziness, abd pain, diarrhea.
  16. H. nana

    Worm & Egg Identification
    • Worm: up to 40mm long
    • Scolex: 4 small suckers & short rostellum with hooks.

    Egg - Round to oval, thin wall 30-45um
  17. H. nana

    Diagnosis
    Recovery of characteristic eggs in stool.

    Adult rarely found
  18. Hymenolepis diminuta: H. diminuta:

    Rat Tapeworm

    Diagnosis & Worm & Egg Ident
    Recovery of eggs. adult rarely found

    Worm: adult 20-60cm long

    • Eggs are similar to those of H. nana
    • *little more round thought* (my thoughts.)
  19. Diipylidium caninum - Dog Tapeworm

    Location / disease / life cycle
    World wide

    • Dogs & cats are host.
    • Humans (usually young children) accidental host via eating fleas.

    indigestion, abd discomfort, eosinophilia
  20. D. caninum

    Diagnosis
    Recovery of egg packets or proglottids.

    • O&P may not be useful if proglottids are not seen. 
    • *Gravid segments are small, white, & motile & sometimes mistaken for pinworms.
  21. Echinococcus granulosis : E. granulosis

    Life Cycle
    • Adult worm in dogs intesting
    • Proglottids & eggs passed
    • Eggs ingested by intermediate host (man)
    • Hatch in duodenum, oncospheres penetrate intestine & moves into bloodstream
    • Various organs affected.
    • cysts contain protoscolices or hydatid sand
  22. E. granulosis

    Disease
    • Echinococcosis,, hydatid cyst disease -
    • Cyst location determines severity
    • Liver 65%
    • lungs 20%
    • brain 1% or kidney 3% or peritoneal 7%
  23. E. granulosis

    Treatment & Diagnosis
    Dx. Abd mass, EITB, pathology (examination of cyst fluid)

    Treatment: Surgery, removal of cysts. 

    If rupture, anaphylactic reactions may occur!
Author
Kwalke12
ID
246768
Card Set
Cestode
Description
Cestode
Updated