Spirocerca Lupi

Question 1

Name the Superfamily, Genus Species, and Common Name.

Answer 1

Superfamily: Spiruroidea Genus Species: Spirocerca Lupi Common Name: Esophageal Worm

Question 2

What is the parasite rating of Spirocerca Lupi?

Answer 2

Rating 1

Question 3

What are the final hosts of Spirocerca Lupi?

Answer 3

Dogs, wolves, coyotes, foxes, etc

Question 4

What are the intermediate hosts of Spirocerca Lupi?

Answer 4

Dung Beetles

Question 5

What are the paratenic hosts of Spirocerca Lupi?

Answer 5

Chickens, birds, lizards

Question 6

What are the characteristic features of identifying Adult Spirocerca Lupi? What about the eggs?

Answer 6

Adults: Pink to red in color and up to 8cm long Eggs: Small and elongated containing L1 (30-35 micrometers)

Question 7

What do Spirocerca Lupi cause in the esophagus?

Answer 7

Large lesions (granulomas) in esophagus, can be size of golf ball

Question 8

Is the life cycle direct or indirect for Spirocerca Lupi?

Answer 8

Indirect :)

Question 9

List all stages (life cycle) of Spirocerca Lupi.

Answer 9

Egg with L1 is passed in feces or vomitus -> Egg is ingested by intermediate host (dung beetle) and hatches in which L1 develops into L3 and encysts -> Dung beetle with L3 can be eaten by paratenic host in which the paratenic host will become infected -> L3 encysts in the viscera of these hosts -> Final host ingests intermediate or paratenic host -> L3 is liberated, penetrates stomach wall, and migrates via celiac artery to thoracic aorta -> 3 months later they cross to esophagus and provoke granulomas and develop to adults in a further 3 months.

Question 10

What is the PPP (pre-patent period) for Spirocerca Lupi?

Answer 10

6 months

Question 11

What happens if granulomas don’t have openings into the esophageal lumen?

Answer 11

Eggs will not be laid in the ingesta and found on fecal flotation.

Question 12

Name the sites of infection for the Adult Spirocerca Lupi.

Answer 12

Adults are embedded within granulomatous nodules in esophagus and stomach.

Question 13

Name the site of infection for the larvae of Spirocerca Lupi.

Answer 13

Larvae cause lesions in wall of the aorta.

Question 14

List the pathogenesis and lesions of Spirocerca Lupi.

Answer 14

1. Migrating larvae scar internal wall of the aorta, which can rupture. 2. Development of osteosarcoma. 3. Spondylosis of the thoracic vertebrae or Osteopathy of long bones, both of which are rare.

Question 15

What are the clinical signs of Spirocerca Lupi?

Answer 15

Esophageal lesions interfere with swallowing and cause persistent regurgitation.

Question 16

List the ways that Spirocerca Lupi is diagnosed?

Answer 16

1. Eggs in the feces or vomitus and can be examined through fecal flotation (Sodium Nitrate). 2. Endoscopy or radiography

Question 17

What is the treatment/prevention for Spirocerca Lupi?

Answer 17

Macrocyclic Lactones (MCL) are used extra-label

Question 18

Is there a registered treatment for Spirocerca Lupi?

Answer 18

No, this is a rare parasite in the United States

Question 19

What are the arrows pointing at in this picture?

Answer 19

Adult Spirocerca Lupi and a granuloma in the esophagus.

Question 20

What is this image showing?

Answer 20

Spirocerca Egg containing larvae. Remember they resemble a paperclip.

Question 21

What is this image showing?

Answer 21

A sarcoma that has developed in the esophagus of a dog infected with Spirocerca Lupi.

Question 22

A dog infected with Spirocerca Lupi is most likely to develop:

a. Diarrhea
b. Anemia
c. Dysphagia
d. Pulmonary insufficiency
e. Right heart failure

Answer 22

C. Dysphagia

Question 23

List the type of hosts for the Spirocerca Lupi life cycle.

Answer 23

Intermediate, paratenic, final host

Question 24

List the common sites of infection in the dog caused by Spirocerca Lupi.

Answer 24

Esophagus (adults)

Question 25

Why are eggs not found in the feces of some animals infected with Spirocerca Lupi?

Answer 25

Many reasons: Long PPP, eggs are in the nodules and aren’t being released, nematodes might not be sexually active