Strongyloides stercoralis Flashcards
Common name
Thread worm
A ____ Transmitted Helminth
Soil
The smallest nematode of man
Strongyloides stercoralis
Rarer than _____
hookworms
A ______ Parasite (both parasitic and Free-living)
Facultative
Usually seen among ______ patients
- elderly
- Immunocompromised
Forms: ____ are rarely seen
Eggs
Eggs will already hatch in the _________
small intestine
Possible although rare: Eggs can be recovered in severe cases; will be seen ___________ in appearance
‘chinese lantern’
____ worms will only be seen in the
free-living cycle
Male
Only _____ worms are recovered in
humans
Female
Females are capable of fertilizing their own
eggs
Parthenogenetic
MOT
arval penetration
HABITAT
small intestine
INFECTIVE STAGE
L3 filariform larva
Strongyloides stercoralis: Life Cycle
Male and Female worm undergo ______
Free-Living Phase
reproduction
Strongyloides stercoralis: Life Cycle
____ are produced by fertilized female worms
Free-Living Phase
Eggs
Strongyloides stercoralis: Life Cycle
Eggs will embryonate in the ____
Free-Living Phase
soil
Strongyloides stercoralis: Life Cycle
Eggs will hatch to release the ______
Free-Living Phase
L1 Larva
Strongyloides stercoralis: Life Cycle
L1 Larva becomes an ___ Larva, eventually, it will then become ___
Free-Living Phase
- L3
- L4
Strongyloides stercoralis: Life Cycle
Forms a new generation of adults
Free-Living Phase
L4
Strongyloides stercoralis: Life Cycle
In some unfavorable conditions, the _______ can be the infective form of filariform
Free-Living Phase
L1 Larva
Strongyloides stercoralis: Life Cycle
Presence of Infective Filariform larvae = start of the ________
Free-Living Phase
parasitic phase
Strongyloides stercoralis: Life Cycle
Infective _______ penetrates a susceptible host
Parasitic Phase
L3 Larva
Strongyloides stercoralis: Life Cycle
Once inside the host, it undergo ________
Parasitic Phase
Heart-Lung Migration
Strongyloides stercoralis: Life Cycle
After migrating, larva matures in the___________
Parasitic Phase
small intestine.
Strongyloides stercoralis: Life Cycle
Larva matures to a _______ worm in the small intestine
Parasitic Phase
female
Strongyloides stercoralis: Life Cycle
Female worm will undergo _________ to fertilize
its own eggs
Parasitic Phase
Parthenogenesis
Strongyloides stercoralis: Life Cycle
Eggs are released by the female worm to be burrowed
in the ___________
Parasitic Phase
small intestine