112.3 Digenea Flukes

What is an Trematoda

Flukes (flatworms)

What are the two groups of flukes

Intestinal/Organ flukes  & Blood flukes

Trematodes require what to complete a life cycles

fresh water

Do the trematodes have one or more intermediate hosts

yes

Who is the first or only intermediate host for trematodes

freshwater snail

What are other intermediate hosts for trematodes

fish, crayfish, crabs, H₂0 plants (bamboo, water cress/ chestnuts)

What are some Intestinal/Organ Fluke Genera

Fasiolopsis buski: small intestine

Fasciola hepatica: liver; bile ducts

Clonorchis (Opisthorchis) sinensis: bile ducts

Paragonimus westermani: lungs

What does Intestinal/Organ flukes eggs look like

operculated

How can humans get infected with Intestinal/Organ flukes

Humans infected by encysted larvae in raw fish, crabs or raw vegetation-bamboo  & water chestnuts, etc.

Are Intestinal/Organ flukes monoecious

yes

Are Intestinal/Organ flukes leaf-shaped adults

yes

What does blood flukes eggs look like

have a spine, but no operculum

How can humans get infected with blood flukes

Humans infected by  larvae that penetrate the skin

Are blood flukes dioecious

yes

What are dioecious

female  in gynecologic canal  of the male

Are blood flukes cylindrical adults

yes

Paragonimus (lungs)

Clonorchis (bile ducts)

Fasciola (liver; bile ducts)

Fasciolopsis (small intestine)

What is the first intermediate hosts for Intestinal/Organ Fluke

fresh water snails

What is Fasciolopsis buski and where does the adult live

Giant intestinal fluke

Small intestine

What is the infective stage for Fasciolopsis buski

metacercariae in raw bamboo or water chestnuts

What are the disease manifestations for Fasciolopsis buski

Adults in duodenum cause ulceration and inflammation of mucosa

diarrhea, anorexia, intestinal obstruction

What are the heavy burdens for Fasciolopsis buski

diarrhea, anorexia, intestinal obstruction

What is Fasciola hepatica where does the adults live

Sheep liver fluke

liver; bile ducts

What is the infective stage for Fasciola hepatica

: metacercaria  encysted in  watercress

What are the Disease manifestation for Fasciola hepatica

Adults live in bile duct/gallbladder

diarrhea, abdominal pain, hepatomegaly, cirrhosis, liver obstruction

What are the heavy burdens for Fasciola hepatica

diarrhea, abdominal pain, hepatomegaly, cirrhosis, liver obstruction

How can one tech differentiate between  Fasciolopsis/Fasciola eggs

measure  with micrometer

Fasciolopsis/Fasciola (Diagnostic egg)

What is the diagnostic stage for Fasciolopsis/Fasciola:

Eggs in stool

Egg large, ellipsoidal with indistinct operculum

What is Clonorchis (Opisthorchis) sinensis and where does the adults live

Chinese liver fluke

bile ducts

What is the infective stage for Clonorchis (Opisthorchis) sinensis

metacercaria encysted in fish

What are the disease manifestations for Clonorchis (Opisthorchis) sinensis

Adults in distal bile ducts

inflammation, fever, diarrhea, bile duct obstruction

What are the heavy burdens for Clonorchis (Opisthorchis) sinensis

inflammation, fever, diarrhea, bile duct obstruction

What is the diagnostic stage for Clonorchis sinensis

embryonated eggs in stool

small, vase-shaped; domed operculum; prominent shoulders

small knob opposite operculum

bile-stained

Clonorchis sinensis ( Diagnostic egg)

Clonorchis sinensis

Are Heterophyes heterophyes and Metagonimus yokogawai eggs similar to Clonorchis sinensis but lack a knob

yes

Where is Heterophyes heterophyes and Metagonimus yokogawai more commonly seen at

Far East

What is Paragonimus westermani and where does the adults lives

Oriental lung fluke

lungs

What is the infective stage for Paragonimus westermani

metacercariae encysted in  freshwater crabs/crayfish

What is the Disease manifestations for Paragonimus westermani

Adults live in lungs

inflammation, persistent cough, hemopytsis (bloody sputum)

What are the heavy burdens symptoms for Paragonimus westermani

inflammation, persistent cough, hemopytsis (bloody sputum

What is the Diagnostic Stage for Paragonimus westermani

unembryonated Eggs in sputum  (or stool)

eggs: urn-shaped with small operculum and shoulders

bile stained

Note: Distinguish this egg from D. latum egg

Paragonimus westermani Diagnostic Egg

What are the characteristics of Paragonimus westermani eggs

urn-shaped

small operculum

What are the characteristics of Diphyllobothrium latum eggs

broadly oval/knob

larger operculum

Paragonimus westermani

Diphyllobothrium latum

Paragonimus westermani

What are some blood flukes species

Schistosoma haematobium:

Schistosoma mansoni:

Schistosoma japonicum:

Where does the adult form of Schistosoma haematobium live at

adults live in veins of urinary bladder; may lead to bladder cancer

Where does the adult form of Schistosoma mansoni live at

adults  in veins of colon

Where does the adult form of Schistosoma japonicum live at

adults in veins of small intestine

What is the infective stage of Schistosoma

cercariae larvae leave snail, swim in water, attach to human skin, lose their forked tail, and penetrate the skin, then enter circulation

Where does the adults in Schistosoma develop/ migrate at

Adults develop in liver/lungs, then migrate in pairs through the hepatic portal vein to the veins of the small intestine, colon, or bladder, depending on the species habitat

How can Schistosoma infect humans

Cercaria larva penetrate skin, lose tail

S. haematobium  

S. mansoni     

S. japonicum          

What is the Disease Manifestations for Schistosomiasis from Cercaria larvae

local dermatitis: red/rash

What is the Disease Manifestations for Schistosomiasis from Larval migration

urticaria, fever, malaise

What is the Disease Manifestations for Schistosomiasis from Eggs

damage to veins & intestinal wall  as eggs penetrate and enter lumen of intestine or bladder

diarrhea or hematuria (S. haemtobium)

ascites, anemia, hypertension, enlarged liver and spleen, hematuria (bloody urine

What is the chronic damage for Schistosomiasis from eggs

ascites, anemia, hypertension, enlarged liver and spleen, hematuria (bloody urine

What is the Diagnostic Stage for Schistosoma haematobium

embryonated eggs in urine (or stool)

egg large, oval

prominent terminal spine

Schistosoma haematobium ( Diagnostic Egg)

What is the Diagnostic Stage for Schistosoma mansoni

embryonated eggs in stool

eggs large, oval

prominent lateral spine

Schistosoma mansoni (Diagnostic Egg)

What is the Diagnostic Stage for Schistosoma japonicum

embryonated eggs in stool

eggs large, round

small, indistinct lateral spine

Schistosoma japonicum (Diagnostic Egg)