HELMINTH: CHAPTER 3

DICROCOELIDAE

Parasites of the bile duct and pancreatic ducts of amphibia, reptiles, birds, and mammals.

Dicrocoelium, Platynosomum, Eurytrema

Genera under Dicrocoelidae

Dicrocoelium dendriticum

• Common names: lanceolate, lancet, or small liver fluke.

Dicrocoelium hospes

• Prevalent in tropical regions.

Dicrocoelium

HOSTS:

• Sheep, goat, cattle, deer

• Pig, dog

• Rarely man

Snail, Ant

I.H. of Dicrocoelium

Bile duct

Predilection site of Dicrocoelium

Snail gut

Miracidium hatches in

Cercaria vitrina

emerges, clumping together in masses called “slime balls” (200–400 cercariae held by gelatinous substance).

Slime balls

200–400 cercariae held by gelatinous substance

Damp weather

Slime balls expelled during

Vegetation

Slime balls adhere to

Abdominal cavity of ants

Metacercaria develop in (Dicrocoelium)

Bile duct

Mature dicrocoelium matures in?

1.5-2 months

Prepatent period of dicrocoelium

6 months

Life span of Dicrocoelium

Cats

Host of platynosomum fastosum

Sublima octona (snail)

1st I.H. of Platynosomum fastosum

Wood louse, sow bug, isopod

2nd I.H. of Platynosomum fastosum

Lizard (Anolis cristatellus)

Paratenic host of Platynosomum fastosum

Liver, Bile duct, Pancreatic Duct

Predilection site of Platynosomum fastosum

Platynosomum fastosum

• Usually mild; temporary inappetence with hepatic dysfunction.

Platynosomum fastosum

• One some cases, progressive icterus may occur → “lizard poisoning”

Eurytrema pangreaticum

Pancreatic and occasionally bile ducts of cattle, buffalo, sheep, goat.

Eurytrema escuderoi

Pancreatic ducts of cattle, carabaos.

Salvador Sonny Escudero

Discovered Eurytrema escuderoi

Eurytrema ovis

Perirectal fat of sheep

Eurytrema coelomaticum

Pancreatic duct of sheep and cattle. All species reported in the Philippines.

Land snails

1st I.H. of Eurytrema coelomaticum

long-horned grasshopper, tree crickets

2nd I.H. of Eurytrema coelomaticum

3 months

Pre-patent period of Eurytrema coelomaticum

Eurytrema coelomaticum

• Low veterinary and public health significance.

• Destruction of duct epithelium (fibrosis) but the parenchyma is normal.

• Pancreas atrophy and chronic wasting and mortality

Opisthorchiidae

• Anterior portion narrower than posterior; lanceolate shape.

Embryonated

Eggs of Opisthorchiidae

Opistorchiidae

Parasites of bile ducts, pancreatic ducts, and gall bladder.

Cat liver fluke

Another term for platynosomum fastosum

Chinese liver fluke

Another term for Opistorchis sinensis

Man, dog, cat, pig

Hosts of Opisthorchis sinensis

Opisthorchis sinensis

• SITE: gall bladder, bile duct, sometimes pancreatic duct and duodenum.

Miracidium

The eggs of Opisthorchis sinensis contain this when laid

40 years

Longevity of Opisthorchis sinensis

Opisthorchis viverrini

carcinogenic; strongly associated with cholangiocarcinoma

Civet cat

Host of Opisthorchis viverrini

Campylobacter

Both are foodborne pathogens that can cause serious health issues, particularly in Southeast Asia.

Opisthorchis viverrini

•  infection may alter the human bile duct environment.

Cholangiocarcinoma (liver cancer)

Interaction of Opisthorchis viverrini and Campylobacter

Opisthorchis tenuicollis/fileneus

Primarily affects cats.

Opisthorchis tenuicollis/fileneus

• Testes lobed (“roseate”)

Praziquantel

Adult flukes treatment

Niclofolan

Eggs treatment

Paragonimidae

Family of paragonimus

oriental lung fluke

Another term for Paragonimus westermani

Paragonimus westermani

• Occurs as cysts in lungs; rarely in brain, spinal cord, and other organs.

Wild and domestic animals

Hosts of Paragonimus westermani

Tiger

Paragonimus westermani is first discovered in?

Brotea aspirata (Snail)

1st I.H. of Paragonimus westermani

Parathelpusa mistio (Crab)

2nd I.H. of Paragonimus westermani

Paragonimus kellicotti

• Cysts in lungs of wild animals, cat, dog, pig, rat, man (North America).

Paragonimus ringer

Occurs in lungs of man

Excystation

Paragonimus, this happens in the duodenum

Eosinophilic peritonitis

Migrating immature Paragonimus flukes has

Bithionol

Treatment of Paragonimus

Salmon fluke, Salmon poisoning fluke

Other term for TROGLOTREMATIDAE

Unembryonated

Egg of Troglotrema when laid

Troglotrematidae

Occur in intestine and cyst-like spaces in various organs.

Neorickettsia helminthoeca

Troglotrematidae are the Reservoir and intermediate host of

Fowl

Hosts of Collyriclum faba

Subcutaneous tissue near cloaca

Collyriclum faba predilection site

Snails (Bithynella)

1st I.H. of Collyriclum faba

Dragonfly naiads

2nd I.H. of Collyriclum faba

Collyriclum faba

Cysts contain pair of worms, black fluid, eggs discharged through pore.

Troglotrema salmincola

Flukes lodge in intestinal mucosa → enteritis due to rickettsial infection.

Troglotrema acutum

Found in frontal and ethmoidal sinuses of carnivores.

Troglotrema acutum

Parasites may cause decalcification and atrophy of sinus walls → eventual perforation of skull.

Apomorphine

Pallative treatment for T. salmincola