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70 Cards in this Set

  • Front
  • Back
What are the two classes of Trematodes?
1.Blood flukes
2.Tissue flukes
What's the proper name for trematodes?
what is unique about tissue vs. blood flukes?
Tissue flukes are hermaphroditic.
what's the infectious stage of
-blood flukes
-tissue flukes
blood = cercariae larvae in H2O

tissue = metacercariae on 2' host or water plants
what is used for treatment of all flukes.. except?

cept for Fasciola hepatica
What is the intermediate host for all flukes?
What tissues do the tissue flukes infect?
1. Liver
2. Intestinal
3. Lungs
How many liver flukes are there?
What are their names?
Clonorchis sinensis
Metorchis conjunctus
Fasciola hepatica
How many Intestinal flukes are there?
What are their names?
Fasciolopsis buski
Heterophyes heterophyes
Metagonimus yokogawai
How many Pulmonary flukes are there?
What are their names?
1. Paragonimus westermani
what are 2 other common names for Clonorchis sinensis?

Where is it distributed?
Chinese or Oriental liver fluke

Found in the Far East.
What are the hosts of Clonorchis sinensis?
Fish-eating mammals

Snails, THEN freshwater fish
How long are C. sinensis adults?
What do their ova look like?
Adults are about 15 mm
Their ova are the smallest of the flukes ova; They have an operculum at the NARROW end of the light-bulb shape.
How is C. sinensis transmitted?
By ingestion of undercooked fish; the metacircariae larvae encyst within the scales.
What is the life cycle of C. sinensis after ingesting fish?
Metacircs crawl into bile ducts --> adults live there --> ova pass to intestine, into feces --> stage of detection.
In general how severe is C. sinensis infection?
Typical symptoms?

-How is it diagnosed?
-How is it prevented?
Not very - asymptomatic.
Indigestion, weight loss, hepatomegaly, jaundice, diarrhea, anemia
-Diagn: ova in stool
-Cook your fish
What liver fluke is so similar to C. sinensis it doesn't have to be identified?
Where is it found? Defin. Hosts?
Metorchis conjunctus, aka N. American Liver Fluke.
Canadian Bears/Wolves/Foxes
What is the cause of Liver Rot?

How is it treated?
Fasciola Hepatica

Treat with BITHIONAL - doesn't respond to Praziquantal.
What is F. hepatica's common name? What are 2 names for infections caused by it?
Sheep Liver Fluke
-Liver Rot
What are hosts of F. hepatica?
Defin: Humans, sheep, cattle, deer, rabbits.
Interm: only snails
App. how large are Adults and Ova of F. hepatica?

-What does the ova look like?
Adults = 25mm; Ova = 140x80u

Ova are identical to D. latum ovum except 2x their size.
How is F. hepatica transmitted?
Metacircs encysted on grass/watercress/bank, soil -> humans ingest them.
What happens after ingestion of F. hepatica?
Larvae penetrate the intest. -> go to liver; adults develop -> ova pass thru bile ducts to intestine; passed in feces.
How severe is f. hepatica infection?
Pretty bad -
Early: fever chills, headache, PAIN blw stomach radiates back.
Late: hepatomegaly biliary obstructn, liver abcesses, jaundice, diarrhea
How is F. hepatica diagnosed?
by presence of ova in feces.
By washing what you eat - watercress for sandwiches.
Of the 3 intestinal flukes, which is most common?
What disease does it cause?
Where is it found?
Fasciolopsis buski

What are the hosts of F. buski?
Defin: Humans, Dogs, Rabbits

Interm: only snails
How long are F. buski adults?
What are their ova like?
25-30 mm

Ova are identical and indisting. from F. hepatica
How is F. buski transmitted?

What happens then?
Metacircs hanging out on waterplants are ingested.

-Adults develop in SMALL intest.
-Ova shed in feces.
What types of symptoms are seen in Fasciolopsiasis?
-Epigastric pain
what are the two intestinal flukes other than fasciolopsis buski?
-Heterophyes heterophyes
-Metagonimus yokagawai
Where are H. heterophyes and Metagonimus yokagawai found?
What are their hosts?
-Defin and -Intermed
-Far East, Egypt, Middle East

-Humans and Fish-eating mammals
-Freshwater fish
What are H. heterophyes and Metagonimus yokagawai v. similar to?
Clinorchis sinensis
-different b/c the metacircariae larvae don't go to the liver via the bile duct; adults just develop in the sm. intestine.
When do H. heterophyes and Metagonimus yokagawai cause symptoms, and what?
In heavy infections only - abdominal pain and diarrhea.
How are H. heterophyes and Metagonimus yokagawai
Diagnosed: ova in stool
Prevented: cook fish well
What is the pulmonary fluke?

What is its infection called? (2 things)
Paragonimus westermani

-Pulmonary distomiasis
What is the common name for Paragonimus westermani?

Where is it found?
Oriental lung fluke

Far East
What are P. westermani's hosts?
Defin: Humans and other mammals

Intermed: Freshwater crabs
Length of P. westermani adult:

Size of ova:
Adult = 10mm

ova = 85 x 55u
Cite 2 unique characteristics of P. westermani ova:
-Instead of at narrow end, the OPERCULUM is at the wide end.
-Ova are yellow-brown naturally.
How does P. westermani infect humans?
the metacircariae larvae get into crabs of all things; then they are ingested, from intest to lungs where Adults develop; Ova are passed in SPUTUM.
why would you see P. westermani in a stool sample?
if you swallowed the sputum and pooped it out.
what 3 symptoms are seen in paragonimiasis, and what can they be confused as?
-Blood-stained sputum
-Pleural pain

Strep pneumoniae
How is paragonimiasis diagnosed and prevented?
Diagn: ova in SPUTUM

Prevent: cook crabs well
what is the blood fluke genus name?
what is its old name?

what three schistosoma species are parasites in humankind?

where is each found?
-Mansoni - Africa and S. america
-Japonicum - Far east
Hematobium - Africa
What are the hosts of Schistos?
Defin: Humans and mammals
Intermed: Snails
How long is a Schistosoma adult?
What are the components of it?
0.6-2.5 cm
-Male gynecophroic canal
-Female lies within the canal
-Not hermaphroditic.
How long are the ova?
-S. mansoni
-S. japonicum
-S. hematobium
Mansoni & hematobium = 150u
Japonicum = 100u
Match the spines w/ the species:
-Lateral spine
-Rudimentary spine
-Terminal spine
Lat = Mansoni - like a shark
Rudi = Japonicum - kinda dumb
Termin = Hematobium - like a dacrocyte
What stages of the fluke larva exist, and which is infectious?
-Cercaria --> infectious
How long is the Cercaria?
What 2 features help it infect?
Cilia help it move
Forked tail helps it propel
What are the 3 stages of Schistosoma infection?
1. Developmental
2. Oviposition/extrusion of ova
3. Proliferation and repair
What occurs in the Developmental period?
Cercariae larva penetrate the skin and Adults form
-Mild allergic rxn at pntrn pnt.
What occurs in the oviposition/extrusion stage?

Ova are laid/penetrate blood vessels.
-Inflammatory Rxn: Immune complexes form, granulomas and fibrous tissue buildup.
What happens during proliferation and repair?
Scar tissue forms and occludes the blood vessel.
What 2 names denote diseases caused by Schistosoma mansoni?
-Intestinal bilharziasis
-Schistosomal dysentary
What 2 names denote diseases caused by Schistosoma japonicum?
-Oriental schistosomiasis
-Katayama disease
What 3 names denote diseases caused by Schistosoma hematobium?
-Schistosomal hematuria
-Urinary bilharziasis
-Vesical schistosomiasis
What are symptoms of infections of S. mansoni/japonicum?
-Malaise, fever
-Abdominal pain, weight loss
What symptoms are seen in infections of S. hematobium?
Suprapubic pain
How are Schistosomal infections diagnosed?

How can all 3 be prevented?
-S. japonicum/mansoni: ova in stool
-S. hematobium: ova in urine
-To prevent: don't go in contaminated water.
What does Schistosomal dermatitis cause?

What animals do the parasites come from?
Swimmer's and Clamdigger's itch.

From Avian/Mammalian Schistosomes pooping in water.
What are symptoms of Swim. Itch?
How is it treated?
How is it prevented?
Itchy rash
Antihistamine lotion
Towel dry vigorously
What are 4 classes of Arthropods and what type of "infection" do they cause?
Crustacians, Chilopoda, Arachnida, Insecta

What are 2 Crustaceans?

1 Chilopoda?
-Crabs and Crayfish

3 species of Arachnida:
Mites aka Scabies
What 3 infections do ticks transmit?
What are the 3 types of lice?
Pediculus humanus var. capitis
Pediculus humanus var. corporis
Phthirus pubis
What's the last really gross type of Arthropoda?
Where is it found?
What does it do?
Myiasis --> Botflies
-South America
-Burrows under skin and might come crawling out :s