Trematodes: flukes = flatworms Flashcards
Platynosomum concinnum (syn. P. fastosom)
- adult characteristics
- egg characteristics
- adults are hermaphroditic
- eggs are operculated (the top that pops off). they are very dense and heavy such that a fecal float is not sufficient, can only do a sedimentation)
Platyosomum concinuum
Life Cycle
prepatent period
- adults in bile ducts of cats make operculated eggs that leave host via feces
- eggs containing a miracidium are ingested by 1st IH - terrestrial snail
- miracidium hatches and undergoes asexual reproduction to become a cercariae
- paratenic host - ingested by pill pug
2nd IH - lizard or gecko ingests the snail containing the cercariae - cercaiae encyst and become metacercariae in bile duct of lizard
- the lizard is ingested by a cat and metacercariae excyst and migrate to the bile ducts/liver and mature
prepatent period = 8 - 12 weeks
Platynosomum concinnum
clinical signs
- normally no severe disease, if chronic will see biliary hyperplasia and liver failure, may see temporary inappetence
- if large numbers will see “lizard poisoning” - weight loss, emaciation, diarrhea, vomiting, jaundice, death
Platyosomum concinnum
diagnosis
treatment
diagnosis: sedimentation - rare to see if bile ducts occluded and necropsy
treatment: none approved though use praziquantel, epsiprantel, fenbendazole and albendazole have been used
Paragonimus kellicotti
- common name
- main infection location and species
- geographic distribution
- any IH and paratenic hosts
= the lung fluke
- found in the lungs of dogs and cats as an incidental host, the primary DH are minks and muskrats
- found in the eastern US
- 2 IH: 1 = aquatic snail, 2 = crayfish or crab
Paragonimus kellicoti
- adult characteristics
- egg characteristics
adults - covered in spines
eggs - much larger than lizard flukes (Playtnosomum concinnum)
Paragonimus kellicotti
life cycle
pre-patent period
- adults found in pairs within cysts in the lungs produce eggs which are coughed up and swallowed and passed thru feces of dogs and cats.
- eggs must reach the water where they enter their 1st IH - the aquatic snail within which they undergo asexual reproduction and become cercariae and emerge from the snail.
- cercariae penetrate their 2nd IH - a crustacean (crayfish) and encyst as metacercariae in heart, liver, muscles.
- the 2nd IH is ingested by the DH. the metacercariae penetrate the intestine and migrate to the lung where they mature (takes between 1 - 2 weeks)
pre-patent period = 3 - 36 days
Paragonimus kellicotti
infective stage
cercariae within their 1st IH the aquatic snail and 2nd IH the crayfish
Platynosomum concinnum
infective stage
cercaiae within their 1st IH - the terrestrial snail and 2nd IH the lizard or toad
Paragonimus kellicotti
clinical signs and pathogenicity
- juvenille migration causes peritonitis and pleural hemorrhage
- adults cause chronic bronchitis, coughing, chronic eosinophilic granulomatous pneumonia
- zoonotic! acquired by eating undercooked crustaceans. dont typically cause clinical signs but if they do:
1st: fever, abdominal pain, diarrhea, pleural effusions.
2nd: bronchopneumonia, coughing - rarely will undergo aberrant migration to the brain cause neuro signs and ultimately death. this only happens in humans.
Paragonimus kellicotti
diagnosis
treatment
diagnosis: sedimentation (very large, heavy eggs), tracheal wash, radiography
treatment: none approved but have used praziquantel, fenbendazole and albendazole
Nanophetus salmincola
- common name
- location and species found
- geographic distribution
- IH and any paratenic hosts
= salmon poisoning fluke
- found in the small intestine of any mammal that eats fish ie dogs, cats, coyotes, foxes, bears, humans, etc.
- found mostly in Pacific Northwest
- 2 IH: 1. aquatic snail 2. fish (trout and salmon)
interesting fact on nanophyetus salmincola
fecal floatation samples sent out from Fl often come back as this fluke which is only found in the Pacific Northwest. it usually ends up being spirometrum or something but think… this fluke is only found on the west coast and cannot be found on floatations, they are found in sedimentations!
Nanophyetus salmincola
adult and egg characteristics
adults: super small
eggs: yellow-brown, operculated
Nanophyetus samincola
life cycle
prepatent period
- adults in intestine produce eggs which pass thru the DH feces
- eggs hatch in water to produce a miracidium. the miracidium penetrates the aquatic snail.
- cercariae emerge from snail and penetrate 2nd IH: fish. they encyst as metacercariae in various tissues.
- 2nd IH: fish are ingested by the DH from which the metacercariae mature in SI.