Blood parasites

Question 1

Babesia canis locations and host tick

Answer 1

North America; rhipicephalus sanguineous

Question 2

Babesia gibsoni

Answer 2

North America, NO HOST TICK, transmission by infected blood from fighting

Question 3

Basics of Babesia

Answer 3

in RBC, trophozoites in red cells, piroplasms are feeding stage (tear drop paired in canis and singly in gibsoni)

Question 4

Life cycle of Babesia

Answer 4

Merozoites taken up by tick, undergo gametogony in tick to sporozoites, dog is infected when tick feeds (this is all like coccidia), erythrocytes are the ONLY host cell parasitized in the dog, piroplasms reproduce asexually. Transplacental transmission occurs

Question 5

What is the infective stage versus the feeding stage of

Babesia?

Answer 5

Sporozoites versus trophozoites (also diagnostic stage)

Question 6

How are Babesia organisms transferred in the tick?

Answer 6

Transovarian and transstadially

Question 7

How do you diagnose Babesia?

Answer 7

Difficult, by blood smear to find piroplams, serology, or most accurate PCR

Question 8

Treatment for Babesia?

Answer 8

Imidocarb diproprionate (will not clear), and combo therapy of azithromycin and atovaquone (only possibility of clearing B. gibsoni); use tick control for B. canis

Question 9

Cytauxzoonosis

Answer 9

Protozoan found in Mid-Atlantic and Mid-west states; bobcats are natural reservoir hosts. Sporozoites invade endothelial-associated mononuclear phagocytes which undergo schizogony and adhere to wall. Diagnose with piroplasms

Question 10

What is the tick associated with Cytauxzoonosis?

Answer 10

Amblyomma americanum

Question 11

What is the pathology asso. with Cyt?

Answer 11

primarily from the tissue phage, histiocytic macrophages attach to vessel wall and cause obstruction

Question 12

What is the major clinical sign asso. with Cyt?

Answer 12

body temperature is very high and then drops below normal after 3-6 days

Question 13

Treatment for Cyt?

Answer 13

Unrewarding, supportive therapy, atavoquone and azithromycin combo–too much tissue damage has already occurred by the time it is initiated

Question 14

Hepatozoon americanum

Answer 14

Fatal tickborne disease in southern US. Amblyomma maculatum is the tick. Dogs become infected by EATING the tick! Coyotes important reservoir

Question 15

Classic pathology of H. americanum

Answer 15

Schizogony in phagocytic cells between myocytes (classic onion skin appearance). Also called granulomatous myositis with extensive atrophy–>pain

Question 16

Diagnosis of H. americanum

Answer 16

Neutrophilic leukocytosis, lifelong infection in dogs

Question 17

Trypanosomes

Answer 17

lives in blood stream, lymph, and tissue spaces. Transmitted by blood sucking arthropods

Question 18

Trypanosoma cruzi

Answer 18

Dogs in southern US, transmitted by kissing bugs. Metacyclic trypomastigotes shed in insect feces. Amastigotes in tissues replicate in cardiac and smooth muscle.

Question 19

Pathology of T. cruzi

Answer 19

Myocardial disease proportional to amastigotes in cardiac muscle. Heart disease is ultimate cause of death

Question 20

Diagnosis and treatment of T. cruzi

Answer 20

usually based on serology. MUST contact CDC if find disease in order to get drug

Question 21

Is T. cruzi zoonotic?

Answer 21

Yes, Chagas’ disease is most common cause of CHF in world

Question 22

What are the five neglected parasitic infections?

Answer 22

Chagas disease, cysticercosis, toxocariasis, toxoplasmosis, trichomoniasis

Question 23

Dipetalonema reconditum

Answer 23

SQ tissue of dogs, southern US, will be less than 270um. **do not confuse with heartworm. decreased in prevalence due to flea control

Question 24

Dracunculus insignis

Answer 24

SQ tissues, raccoon is normal host, females associated with skin ulcers. Females deposit L1 into water, gets taken up by copepod and develops into L3, host ingests PH and the larvae migrate through intestine to get to SQ. Treatment is surgical removal, disruption of worm leads to anaphylaxis!

Question 25

Thelazia californiensis

Answer 25

tear duct or conjunctival sac in Western states. Picked up from fly, needs to be removed and then the eye flushed

Question 26

Neospora caninum

Answer 26

FATAL protozoan likened to T. gondii. Major cause of bovine infertility and abortion. Coccidian, dogs/coyotes are DH. sporulated oocysts consumed by hosts. IH has asexually reproducing tachyzoites and tissue cysts. Can be transmitted transplacentally. Primary CNS pathogen in dogs

Question 27

What is the classic sign of N. caninum?

Answer 27

Hind limb paralysis and hyperextension.

Question 28

Dioctophyme renale

Answer 28

Giant kidney worm, females can be up to 1 meter long and is the largest nematode. DH is carnivores, adults usually in right kidney. Eggs are passed in the urine and hatch when swallowed by IH. Worms completely destroy parenchyma. May be reluctant to walk, have hematuria. Diagnosis by finding eggs in urine sediment. have to remove entire “kidney”

Question 29

Pearsonema spp.

Answer 29

From earthworms, these worms are tiny, embed in bladder mucosa, no symptoms