Lecture 1: Trematodes Flashcards Preview

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Flashcards in Lecture 1: Trematodes Deck (63):
1

trematodes are

flukes

2

lizard poisoning fluke

platynosomum concinnum

3

where is the fluke found in the DH

Bile ducts of cats

4

Intermediate hosts of platynosomum concinnum (lizard fluke)

terrestrial snail (subulina, eulata)
anolis lizards

5

paratenic host of platynosomum concinnum (lizard fluke)

pill bug

6

eggs of platynosomum concinnum (lizard fluke)

operculated eggs containing miracidium

7

what infects the snail (IH) in platynosomum life cycle

miracidium ingested by 1st IH the terrestrial snail

8

what leaves the terrestrial snail IH in platynosomum LC

miricidium hatches and sporocysts, cercariae burst out of snail

9

after the 1st IH (terrestrial snail) in platynosomum LC what happens next

cercariae can be ingested by pill bug or anole
anole can also eat infected pill bug
cercariae then encyst to metacercariae in bile ducts of anole lizard

10

platynosomum LC

Operculated eggs
miracidium in terrestrial snail
cercariae leave snail into 2IH
2IH has encysted metacercariae which is consumed by cat

11

dz seen with platynosomum in cats

typically asymptomatic
liver dz
cholangiocarcinoma

12

diagnosing platynosomum

fecal sedimentation - can be hard to pick up still

eosinophilia, increased ALT
visible on necropsy

13

treatment choice for platynosomum

praziquantel
no labeled treatments though!

14

the lung fluke

paragonimus kellicotti

15

lung fluke DH (paragonimus)

dogs, cats, mink, muskrat

16

lung fluke IH (paragonimus)

1st IH: aquatic snail (melania, ampullaria)
2nd IH: crayfish or crab

17

regional distribution of paragonimus (lung fluke)

eastern US

18

adult morphology differences of paragonimus vs. platynosomum

paragonimus is 2x larger and integument is covered in spines

19

adult paragonimus found in the __ of DH and passed in __

lungs (inside cysts), feces

20

paragonimus eggs require __ to hatch/complete LC

Water
miracidium will penetrate aquatic snail

21

what emerges from the aquatic snail in paragonimus LC

Cercariae
this penetrates the 2IH (crustation)

22

what happens to the cercariae of paragonimus in the crustation

encysts as metacercariae in heart, liver, muscles

23

what happens to the adult paragonimus in the lungs

they make a cyst, may be a pair in one

24

how do paragonimus flukes survive in the lung

cleave IgG to reduce eos and down regulate host inflamm response

25

clinical signs with paragonimus kellicottii (lung fluke)

juvi migration - peritonitis, hemorrhage
adults - chronic bronchitis, coughing, eos, pneumonia

26

is paragonimus kellicotti zoonotic?

yes! humans can get the lung fluke by ingesting undercooked crustations (crabs, cray fish)

27

what CS can be seen with paragonimus kellicotti infection in dogs, cats, and humans

normally asymptomatic
can have abdominal pain, diarrhea from fluke migration
can have pleural effusion, coughing, bronchopneumonia, chest pain from encysted flukes

28

what is a severe CS that can happen when paragonimus kellicotti infects humans

aberrant migration to the brain! (headache, vomiting, seizures, coma, death) usually seen in young adults 15-30yo

29

paragonimus kellicotti diagnosis

sedimentation
tracheal wash
rads

30

treatment for paragonimus kellicotti

none approved
same as with platynosomum; praziquantel, fenbendazole, albendazole (crosses BBB)

31

the salmon poisoning fluke

nanophyetus salmincola

32

region for nanophyetus salmincola infections

salmon poisoning fluke is mostly seen in pacific NW (travel hx is important)

33

DH for nanophyetus salmincola

dogs, cats, coyote, fox, fish-eating mammals (bears, humans)

34

IH for nanophyetus salmincola

1IH - aquatic snail (oxytrema)
2IH FISH (trout or salmon)

35

describe the eggs of flukes

operculated, usually darker colored and dense

36

describe eggs and adult nanophyetus salmincola

adults are very small, shaped kind of like a yeast/peanut
eggs are large, yellow-brown and operculated

37

LC of nanophyetus salmincola

miracidium penetrates aquatic snail
cercariae emerges from snail and penetrates fish
encysts as metacercariae in fish tissues
fish ingested by DH and fluke matures in SI
NO MIGRATION

38

CS of salmon poisoning

usually asymptomatic if only a nanophyetus salmincola infection
if co-infected with neorickettsia helminthoeca will see fever, anorexia, V/D, hemorrhagic enteritis, lymphadenopathy and death

39

treatment for salmon poisoning

praziquantel, fenbendazole for flukes
doxycycline for neorickettsia

40

diagnosis of nanophyetus salmincola

sedimentation

41

the canine blood fluke

heterobilharzia americana

42

describe the adult heterobilharzia mericana

look like nematodes, but they are flukes. NOT hermaphroditic like the other flukes discussed.

43

Where does the male carry the female heterobilharzia americana

in the gynecophoric canal

44

where is heterobilharzia located in DH

mesenteric and hepatic veins of dogs, bobcats, raccoons

45

where is heterobilharzia americana seen most often

gulf coast, louisiana bayous, mississippi delta

46

IH for heterobilharzia americana

aquatic snail (lymnaea)

47

how many IH are involved in LC for heterobilharzia

one, the aquatic snail

48

cercariae can cause skin irritation from penetration in which species of flukes

heterobilharzia americana zoonotic, causes "swimmer's itch" aka cercarial dermatitis

49

treatment for most flukes

praziquantel, fenbendazole, albendazole

50

diagnosis for most flukes

fecal sedimentation

51

fluke which inhabits the SI of dogs and cats that has a unique route of trasmammary transmission

alaria spp.

52

IH for alaria spp.

1IH: aquatic snail (helisoma)
2IH: tadpole (rana pipiens)
paratenic hosts

53

describe the adult alaria flukes

spoon-shaped, have weird appendages at the anterior end that look like antenna

54

LC of alaria spp.

eggs pass in feces from DH
1IH miracidium penetrates aq snail and cercariae emerge
cercariae penetrate tadpole (2IH) and develop into mesocercaria and metacercariae - this can be ingested by paratenic host

55

infective stage of alaria to cat and dog

metacercariae

56

if a lactating cat ingests mesocercariae (juvi fluke) what happens

can migrate to mammary gland and infect kittens

57

alaria spp has __ migration

lung - can cause pulmonary hemorrhage

58

are there any approved drugs for treating flukes in SA?

No, usually use praziquantel, fenbendazole, and albendazole off label for treatment

59

flukes with zoonotic potential

paragonimus kellicotti (lung fluke); aberrant migration to brain
heterobilharzia americana (canine blood fluke); swimmer's itch or cercarial dermatitis

60

phylum for flukes

Phylum; platyhelminthes "flatworms"
includes the trematodes "flukes" and cestodes "tapeworms"

flukes are in the class Trematoda

61

fluke morphological recap

dorsoventrally flattened
have a tegument (can be smooth or spined)
attachment organs; anterior feeding oral sucker and ventral attachment acetabulum
digestive ssytem has two blind ceca
excretory and nervous systems
hermaphroditic (with exception of schistosomes like heterobiharzia americana)

schistosomes "split bodied flukes" inhabit blood vessels of DH, they are NOT hermaphroditic and they look more like "roundworms". Males have a gynecophoric canal to hold female in. We only discussed the canine blood fluke, heterobilharzia americana

62

typical lifecycle of fluke

operculated egg
miracidium
cercaria
metacercaria - infective stage
adult fluke

63

infective stage of fluke

metacercaria