Trematodes Flashcards
Schistosome characteristics
Seperate sex
Non-operculated eggs
Blood flukes
Daughter sporocyst
No metacercaria
Human is definitive host
S. mansoni characteristics
Has papilla located on tegument of females
Egg shape: Lateral spine (sticks out to side)
Eggs are excreted in feces
Adults mainly inhabit mesenteric menules of large intestine
Pathology: Portal hypotension, liver disease, fibrosis, hemmorhage
S. japonicum characteristics
Smooth papilla on tegument of females
Egg shape: No spine
Eggs are excreted in either urine or feces(!)
Adults mainly inhabit mesenteric venules of small intestine
Pathology: high egg production, can reach CNS
S. hematobium chracteristics
Few papilla located on tegument of females
Egg shape: Terminal spine
Eggs are excreted in either urine (!) or feces
Adults mainly inhabit mesenteric venules of urinary bladder
Pathology: Hermaturia, bladder cancer
F. hepatica characteristics
Spines on tegument
Eggs hatch in water and excreted in feces
Eggs are opperculated
Metacercaria are carried on aquatic plants
Adults inhabit: liver, bile duct of liver
Adult features: cephalic cone shape, shoulders, highly branched cecum (intestine)
Pathology: Destruction of Bile Duct, anemia
F. hepatica lifecycle
Unembryonated eggs passed in feces > Embryonate in water > Micricidia hatch and penetratil snail > become sprorocysts -> Rediae -> Cercariae in snail tissue > Free swimming cercariae encyst on water plants > Metacercariea on water plant > Waterplant ingested by human, sheep, or cattle > Encyst in duodenum > Adults in hepatic bilary ducts
F. buski characteristics
Smooth teguments
Eggs hatch in water and excreted in feces
Opperculated eggs
Cone-chaped, non protruding head
Metacercaria are carried on aquatic plants
Adults inhabit: small intestine
Adult features: giant, gravid anterior, uterus; Branched testes, but cecum is normal
Pathology: Diarrhea, intestinal blockage, systemic toxicity, malnourishment
F. buski lifecyle
Unembryonated eggs passed in feces > Embryonate in water > Micricidia hatch and penetratil snail > become sprorocysts -> Rediae -> Cercariae in snail tissue > Free swimming cercariae encyst on water plants > Metacercariea on water plant > Water plant ingested by humans/pigs > Exit cyst in duodenum > Adults in hepatic bilary ducts
C. sinensis characteristics
Requires 2nd intermediate host
Smooth teguments
Eggs hatch in snail
Eggs are excreted in feces
Metacercaria are carried on fish
Adults inhabit: Bile duct
Adult features: elongated, branched uterus anteriorly, testis posteriorly, cecum not wavy
Pathology: Destruction of bile duct, jaundice, heptamegaly
C. sinensis lifecycle
Embryonated eggs passed in feces > Eggs are ingested by snail > Miracida -> Sporocysts -> Rediae -> Cercariae > Free-living cercariae encyst in flesh on fish > Become Metaceriae ingested by human > Exit cyst in intestines > Mature in bile duct
P. westermani charcteristics
Eggs excreted in sputum and feces
Eggs hatch in water
Metacercaria are carried on crustaceans
Adult features are coffee bean shape and wavy cecum
Spines located on tegument
Adults inhabit the lungs
Pathology: cough
P. westermani lifecycle
Unembryonated eggs passed in feces > Embryonate in water > Micricidia hatch and penetratil snail > become sprorocysts -> Rediae -> Cercariae > Cercariae invade crustacean and encyst into metacercariae > Human ingests infected crustacean > Exits from cyst intestines > Adults in lay eggs in lungs > Eggs are re-swallowed
Schistosome lifecyle
Eggs are passed in feces (s. mansoni|s. japonicum) or urine (s. hematobium) > Eggs hatch in environoment releasing miracidia > Mericidia penetrate snail tissue > Sporocysts in snail > Cercariae are released into water > Penetrate human skin > Cercariae lose tails during penetration become schistosomulae > Enter circulation > Migrate to portal blood in liver and mature into adults > Paired adults enter mesenteric venules of bowel/rectum
