Lecture 1 - Small Animal (Babesua and Cytaux) Flashcards
an apical complex allows a protozoa to do what
enter cells
what are apicomplexan characteristics
- apical complex
- gliding motility
- sexual and asexual reproduction
what are piroplasms
- intracellular, apicomplexan parasites
- tick-transmitted
- indirect life cycles
- infect vertebrate blood cells
what is the definite host of piroplasms? why?
ticks; asexual reproduction occurs in them
what is the intermediate host of piroplasms? why?
vertebrates; only asexual reproduction occurs
when piroplasms are identified in erythrocytes, they are classified as
large or small
what piroplasms infect dogs
babesia gibsoni and vogeli
what piroplasms infect cats
cytauxzoon felis
what is a hallmark diagnostic finding of babesia spp.
anemia and thrombocytopenia
what spreads B. vogeli
rhipicephalus sanguineus (brown dog tick)
what spreads B. gibsoni
Haemaphysalis spp.
describe the lifecycle of babesia
- sporozoites transmitted by ticks
- trophozoites undergo binary fission to become merozoites (daughter cells)
- ingestion of RBCs containing babesia by the tick
- babesia create sporozoites
what are the 4 ways babesia are transmitted
- sporozoites injected by tick bite
- dog-to-dog (fighting)
- blood transfusion
- transplacentally (vertically)
what is the pathogenesis of babesia
- direct destruction of erythrocytes
- autoantibodies directed against host erythrocytes
a 3 y/o pitbull presents for injuries sustained after a dog fight. The patient is febrile, lethargic, and has thrombocytopenia. what is the diagnosis? be specific.
babesia gibsoni
a 7 y/o Great Pyrenees used as a farm dog present for tick attachment. The patient has pale mucous membranes and lymphadenomegaly upon palpation. RBC morphology reveals agglutination and spherocytes. what is the diagnosis? be specific.
babesia vogeli
what diagnostic finding is more common with babesia infections
thrombocytopenia
T/F: there are no pathognomonic biochemical findings of babesia
TRUE
what are 3 diagnostic tests you can use to diagnose piroplasms
- parasite visualization (via blood smear)
- serology
- PCR
if you only have time for one test to diagnose babesia, what will you do?
PCR
what may cause artifacts on babesia parasite visualization
Howell-jolly bodies, water, mycoplasma hemocanis
T/F: babesia vogeli is large
TRUE
T/F: serology is species-specific
FALSE - can cross-react
T/F: a serologic false negative can occur because antibodies take a while to generate
TRUE
why would a negative PCR test occur
parasite load is too low to be detected
what is recommended treatment for both B. gibsoni and cytauxzoon felis
azithromycin and atovaquone
what are the 5 risk factors for Babesia
- breed (greyhounds, pit bulls, etc.)
- dog bite
- exposure to ticks
- transfusions
- splenectomy
T/F: babesiosis can be acute or chronic
TRUE
14 m/o outdoor/indoor cat presents with a 7-day history of lethargy, fever, and emesis. The patient is laterally recumbent upon presentation and diagnostics reveal pancytopenia (anemia, neutropenia, thrombocytopenia). what is your diagnosis?
cytauxzoon felis
summarize the life cycle of cytauxzoon felis
- lone star tick ingests infected RBCs
- sporozoites infect macrophages throughout the body
- schizonts rupture and release merozoites
who is the natural resivoir host for cytauxzoon felis
bobcats
T/F: a chronically infected survivor can become a natural reservoir host
TRUE
Schizonts of cytauxzoon felis infect what two WBCs
macrophages and monocytes
what is the pathogenesis of cytauxzoon felis
- direct destruction of RBCs
- widespread dissemination of schizont-laden macrophages
- inflammation that recruits macrophages and monocytes
a 5 y/o DSH presents for acute febrile disease and dyspnea. Patient is an indoor apartment cat that has access to a balcony. mucous membranes are icteric. what is your diagnosis?
cytauxzoon felis
why shouldn’t a PCR or serology test be done on a cat you expect has C. felis
you won’t have the results back fast enough to treat
summarize the progression of symptoms of C. felis in cats
signs 12-15 days after infection - ADR to coma in days - death within 5 days of clinical signs
what cats are at higher risk of contracting C. felis
- outdoor cats
- cats in the southeast and midwest
is there season prevalence associated with C. felis infection? if so, when?
Yes, April to August
if C felis is diagnosed and treated quickly what is the survival rate of cats
60%
