Nematode Parasites of the Urinary Tract, Eyes, Integumentary, and central nervous systems

Which Capillaria sp is found in the urinary tract of dogs, foxes, wolves, coyotes, and cats?

Capillaria (Pearsonema) plica

Which Capillaria sp is found in the urinary bladder of only cats?

Capillaria (Pearsonema) feliscati

What are the clinical signs of Capillaria sp in the urinary tract in dogs and cats?

• relatively harmless

• occasional cystitis, difficulty with urination

How do we diagnose Capillaria sp in the urinary tract?

by observing eggs (65 × 35 micrometers) in clean urine catch

How do we treat Capillaria sp. in the urinary tract?

Ivermectin

How do we control Capillaria sp in the urinary tract?

environmental hygiene

Which parasite does this lifecycle match:

• obligate indirect with earthworms as intermediate host

• rodents/birds may serve as paratenic host (“bridge ecological gap”)

• prepatent period 60 days

Capillaria sp

What size worms are Capillaria sp?

13-30mm for males

30-60mm for females

Which parasite egg is shown in the image?

Capillaria sp

What is the common name of Dioctophyma renale?

giant red kidney worm

What parasite is the largest of parasitic nematodes, with females being up to 100cm long and 1cm in diameter?

Dioctophyma renale (giant red kidney worm)

Which parasite matches this lifecycle:

• opportunistically infects pet dogs

• important reservoid hosts include wild canidae, bear, mink, raccoon, otter

• obligate indirect lifecycle

• free living awuatic annelids are intermediate host

• crayfish, frogs, fish are paratenic hosts

• infective larvae 1) penetate bowel, 2) develop in peritoneum, 3) penetrate kidney, and 4) develop to adults and reproduce

• prepatent period 138 days

Dioctophyma renale (giant red kidney worm)

How do we diagnose Dioctophyma renale?

by finding eggs (68 × 44 micrometers) in urine sediments

Which parasite is depicted in the image?

Dioctophyma renale

Where do adult Dioctophyma renale often reside?

pelvis of the kidney

Disease of Dioctphyma renale is caused by the destruction of what?

the parenchyma of the kidney, and eventually only the capsule remains

What happens if worms of Dioctophyma renale extend down to the ureter?

blockage/tissue destruction results in inability to remove waste from the body (uremia)

The presence of free Dioctophyma renale worms in peritoneum stimulates what?

inflammation, adhesions, and peritonitis

Severe infections of Dioctophyma renale ultimately results in what?

kidney failure and death

Sometimes infections of Dioctophyma renale occur without symptoms of clinical disease. Why?

• worms show a tendency to parasitize only the right kidney

• renal function is impaired, but functional with only one kidney

What are the common names of Dracunculus sp?

• guinea worm

• fiery serpent

Which parasite species is on the brink of eradication by international public health programs?

Dracunculus sp

Adult worms of Dracunculus sp are parasitic where?

in subcutaneous tissues of North American carnivorous mammals, usually seen on a limb

Which parasite does this lifecycle match:

• opportunatically infects pet dogs and cats

• important reservoir hosts are wild canidae, raccoon, otter, muskrats

• carnivores frequenting aquatic habitats most susceptible

• obligate indirect lifecyle

• free living aquatic copepods are intermediate host

• frogs may be an important paratenic host

• 1) accidental ingestion of IH containing infective larvae OR predatory ingestion of PH containing infective larvae, 2) infective larvae migrate through intestinal wall, reach SC tissues within 3 weeks, sexual maturity and reproduction reached 6-7 weeks PI, 3) host rx results in blister/ulcer at end of migration tunnel, 4) female workers protrudes uterus when stimulated by contact with water and discharges larvae

Dracunculus insignis

This image depicts what parasite?

Dracunculus insignis

What is the parasitic species of Dracunculus that affects humans residing in Africa?

Dracunculus medinensis

Is there an effective treatment for Dracnculus medinensis?

No

What happens if a Dracunculus medinensis breaks during extraction?

significant host reaction, inflammation, anaphylaxis, and possible death

Thelazia species are parasitic where?

in conjunctival and lacrimal sac

Which Thelazia species affect dogs, cats, people, sheep, and deer?

T. californiensis

Which Thelazia species affect horses?

T. lacryrmalis

Which Thelazia species affect cattle?

T. glucosa

Which Thelazia species affects people, dogs, and cats only?

T. callipaeda

Whcih parasite does this lifecycle match:

• obligate indirect lifecycle is characteristic of the family

• Flies are intermediate host

• Feed on lachrymal secretions, ingest eggs, and develop into 3rd larvae within the fly

• transmission back to DI when they return to feed

Thelazia species, Spiruidae family

How do we treat for Thelazia sp. infections?

macrocyclic lactones - 200 micrograms/kg ivermectin SID or 1-2 drops 1% Moxidectin OU or Tpical moxidectin + Imidacloprid (advantage multi)

What is the pathogenic effects of infection with Thelazia sp.?

• irritation and conjunctivitis

• increased tearing attracts flies which leads to increased transmission

This image matches what parasite species?

Thelazia sp

How can you differentiate Thelazia sp from Onchocerca lupi in the dog eye?

• Thelazia sp is a smal hookworm like body

• Onchocerca lupi is a long filametous worm

What may help with prevention/transmission of Canine Ocular Onchocerciasis?

Canine Heartworm prophylaxis

Does Onchocerca lupi show zoonosis?

Yes

How is Onchocerca lupi transmitted?

Bite of black fly

Where can adult worms of Onchocerca lupi be found in the dog?

ocular nodules and granulomatous masses around eyeball/conjunctiva

Which parasite is seen in the image on the left?

Thelazia sp

Which parasite is seen in the image on the right?

Onchocerca lupi

What is the common name of Paraelaphostrongylus tenuis?

Meningeal worm

Paraelaphostrongylus tenuis is a naturally occuring parasite of which animal?

White tail deer

Which parasite is a metastrongyloid parasite with an obligate indirect life cycle and shows significant morbidity and mortality in moose and elk?

Paraelaphostrongylus tenuis

Describe the seasonal epidemiology of Paraelaphostrongylus tenuis .

• infective larvae acquired in summer

• clinical signs appear during fall-early winter

• consistent with deer activity on pastures

What are the first clinical signs of animals affected by Paraelaphostrongylus tenuis?

• lateral recumbency, dysorexia, not doing right

• ataxia, head tilt, circling

• paraparesis with advanced disease

How do we diagnose infection of Paraelaphostrongylus tenuis?

• antemortem diagnosis by exclusion

• clinical signs can be suggestive

• use complete database: signalment, history, CBC/Chem, CSF analysis, diagnostic imaging (CT)

• definitive diagnosis by necropsy

How do we treat infections of Paraelaphostrongylus tenuis?

FBZ at 20-50 mg/kg SID x5 days as parasiticide

Flunixin meglumine 1mg/kg BID x5 days for analgesia/pain

DMSO/prednisolone as steroidal tx to cross the BBB

How do we prevent infections of Paraelaphostrongylus tenuis?

• limit contact with white tail deer

• gravel/limestone barriers to snail-slug migration around fence lines

• improve drainage

Which parasite is seen in this image (arrow pointing at worm)? DVS = dorsal venous sinus.

Paraelaphostrongylus tenuis

Which parasite is seen in this image?

Halicephalobus gingivalis

Which parasite may be a facilitating factor for drug resistance in Haemonchus?

Paraelaphostrongylus tenuis

Which parasite is a naturally occurring free living nematode and opportunstically infects horses with fatal consequences?

Halicephalobus gingivalis

How do we definitively diagnose Halicephalobus gingivalis?

at necropsy, clinical presentation is generalized not doing right, respiratory, renal effects, etc

Does Halicephalobus gingivalis portray zoonosis?

Yes

Is there an effective treatment for Halicephalobus gingivalis?

No