PR CST Flashcards
smallest tapeworm of man and most common cestode infection
Hymenolepis nana
Hymenolepis spp.
Habitat
small intestine (upper portion of ileum)
Hymenolepis spp.
MOT
- ingestion
- H. nana : Autoinfection
Hymenolepis nana
FH
Humans
Hymenolepis nana
Common name
Dwarf tapeworm
Hymenolepis nana
IH
- Ctenocephalides canis (Dog Flea)
- Pulex irritans (Human Flea)
- Xenopsylla cheopsis (Rat Flea)
- Tenebrio (Rice Beetle)
- Tribolium (Flour Beetle)
Hymenolepis nana
IS
- Indirect - Cysticercoid
- Direct - Embryonated Egg
Hymenolepis nana
Adult Worm (Scolex)
- Subglobular or rhomboidal
- Four suckers
- Armed rostellum : 20-30 hooklets
Hymenolepis nana
Mature Proglottid (Testes and Ovary)
Testes - 3 ovoid
Ovary - 1 bilobed
Hymenolepis nana
Gravid Proglottid
- Twice as wide as long
- Sac-like uterus filled with eggs
Hymenolepis nana
Egg
- Circular and thin-shelled
- Oncosphere with hexacanth embryo
Hymenolepis nana
Egg (# of hooklets)
6 hooklets
Hymenolepis nana
Egg (polar thickenings and polar filaments)
Presence of polar thickenings and 4-8 polar filaments
Hymenolepis diminuta
FH & AH
FH : Rat
AH : humans
Hymenolepis diminuta
Common name
Rat tapeworm
Hymenolepis diminuta
IH
Variety of arthropods
- cockroach, rat flea, flour moths, flour beetles
Hymenolepis diminuta
IS
Cysticercoid larva
Hymenolepis diminuta
Adult Worm (Scolex)
- Knob shaped and unarmed rostellum
- 4 suckers
Hymenolepis diminuta
Mature Proglottid (Testes and Ovary)
- Wide but short
- Testes : 3 ovoid
- Ovary : 1
Hymenolepis diminuta
Gravid Proglottid
Very wide but short
Hymenolepis diminuta
Eggs
- large, ovoid, yellowish
- striated shell
- six-hooked oncosphere
Hymenolepis diminuta
Eggs appearance
Fried egg appearance
Hymenolepis diminuta
Egg (polar thickenings and polar filaments)
Presence of polar thickenings, but no polar filaments
Hymenolepis diminuta
Eggs (hooklets)
fan-like arrangement
Hymenolepis spp.
Pathology
Adult : epigastric pain, nausea, vomiting, anorexia, diarrhea
Hymenolepis spp.
Diagnosis
Stool exam
Hymenolepis spp.
Treatment
Praziquantel
Dipylidium caninum
Common name
Double Pored Tapeworm, Dog Tapeworm, Flea Tapeworm, Cucumber Tapeworm