Toxoplasmosis Small Animal Medicine 1

Front 1

What is the agent that causes toxoplasmosis?

Back 1

Protozoa coccidian Toxoplasma gondii

Front 2

What is the definitive host of toxoplasmosis?

Back 2

Cats**they complete the life cycle

Front 3

If a human ingests oocysts from cat feces and the cat pooped 22 hours ago, is the human at risk of developing toxoplasmosis? Why or why not?

Back 3

No, because it takes 1-5 days for the oocysts to sporulate in the environment, so if the oocysts have been in the environment less than 24 hours the toxoplasmosis cannot cause disease.

Front 4

What is the distribution of toxoplasmosis?

Back 4

Enzootic world wide

Front 5

How prevalent is toxoplasmosis in the US in cats and humans?

Back 5

~30-40% of cats and humans in the US are seropositive
-dogs ~20%

Front 6

Most of the dogs that were diagnosed for toxoplasmosis via histopathology were most likely really infected with _________.

Back 6

Neosporum

Front 7

What are the 3 routes of transmission of toxoplasmosis?

Back 7

1) Ingested of infected animal tissues
2) Ingestion of oocysts shed in cat feces
3) Congenital (transplacental)

Front 8

What is the primary source of toxoplasmosis infection in cats?

Back 8

Ingested of infected animal tissues
-important in dogs & humans too

Front 9

What 3 species are most commonly infected with toxoplasmosis by ingestion of oocysts in cat feces?

Back 9

humans, dogs, rodents

Front 10

When can congenital transmission of toxoplasmosis occur?

Back 10

Only when toxo is acquired DURING pregnancy, then it can be transmitted to the fetus

Front 11

Why is diagnosis of toxoplasmosis via looking for oocysts in the feces not efficient?

Back 11

Because cats only eliminate oocysts for about 24-72 hours and then NEVER eliminates them again
-cats that shed virus do not have clinical signs

Front 12

What clinical signs often develop in cats after ingesting infected animal tissue for the first time?

Back 12

Cats may develop a self-limiting small bowel diarrhea

Front 13

What is the difference b/w acute and chronic toxoplasmosis?

Back 13

Acute: clinical signs occur at the time of infection
Chronic: signs occur during reactivation, caused by immunosuppression (also called secondary toxoplasmosis)

Front 14

What are 3 non-specific signs of toxoplasmosis?

Back 14

Fever, anorexia, depression

Front 15

The specific clinical signs of toxoplasmosis depends on the affected organs. What are 5 organs that can be affected by toxoplasmosis?

Back 15

1) Lung
2) Eyes
3) Brain
4) Liver
5) Skeletal muscle

Front 16

What clinical signs develop when toxoplasmosis affects the lungs?

Back 16

Acute necrotizing pneumonia

Front 17

What clinical signs develop when toxoplasmosis affects the eyes?

Back 17

Uveitis

Front 18

What are 2 clinical signs that develop when toxoplasmosis affects the brain?

Back 18

Seizures & ataxia

Front 19

What is a clinical sign of toxoplamosis affecting the liver?

Back 19

Icterus

Front 20

What are 3 clinical signs of toxoplasmosis affecting skeletal muscle?

Back 20

Myositis with hyperesthesia (increased sensitivity to touch), stiff gait, and muscle pain

Front 21

True or false. Clinical signs are more severe in kittens that are infected transplacentally.

Back 21

True

Front 22

What will you find on a CBC of an animal with toxoplasmosis?

Back 22

-Leukopenia (acute) or neutrophilic leukocytosis
-non-regenerative anemia

Front 23

What will you see on a biochemistry profile of an animal with toxoplasmosis?

Back 23

-depends on what organ system is affected
~Liver: increased ALT & ALP
~Pancreas: increased TLI
~Muscle: increased CK & AST

Front 24

What will you see on radiographs of an animal with toxoplasmosis?

Back 24

-Interstitial pneumonia (sometimes alveolar)
-Pleural effusion
-Usually don't help much

Front 25

What lab abnormalities can be detected in the CSF of an animal with toxoplasmosis that's affected the brain?

Back 25

Increased in protein and cell count
-protozoal so mostly mononuclear cells

Front 26

Is demonstration of the organism a very efficient method for diagnosing toxoplasmosis? Why or why not?

Back 26

Very difficult, bradyzoites and tachyzoites are RARELY detected in tissues, effusions or fluids

Front 27

What sample(s) do you mail in when trying to diagnose toxoplasmosis?

Back 27

CSF or aqueous humor, but can also get + in normal cats

Front 28

True or false. Antibodies, antigens and immune-complexes to toxoplasmosis can only be detected in sick cats.

Back 28

False, found in serum sick and normal cats

Front 29

What type of antibody increase correlates with toxoplasmosis?

Back 29

IgM

Front 30

When do IgM titers rise with toxoplasmosis infection? How long do they persist?

Back 30

Titers rise 1-2 weeks
Persist for less than 12 weeks
*rises w/ acute toxo infections

Front 31

What level of IgM titers suggest an active toxoplasmosis infection?

Back 31

*Titers 1:256

Front 32

How long does it take IgG titers to rise with toxoplasmosis? How long do they persist?

Back 32

Rise in 2-4 weeks
Persist for longer than 1 year

Front 33

When do IgG titers suggest an active toxoplasmosis infection?

Back 33

4 fold increase over 2-3 weeks suggests an active infection

Front 34

What are 4 components/options for treating toxoplasmosis?

Back 34

1) Supportive therapy
2) Antimicrobials
3) Topical corticosteroids
-for uveitis
4) Treat secondary infections

Front 35

What 2 antimicrobials are most effective for treating toxoplasmosis?

Back 35

1) Clindamycin
2) Sulfonamide + trimethropin

Front 36

True or false. Antimicrobials work for acute toxoplasmosis, reactivation of toxoplasmosis, and to eliminate the cysts.

Back 36

False, only works for acute and reactivated toxoplasmosis, does not eliminate the cysts- can only treat active infection

Front 37

How long does it take clinical signs of toxoplasmosis not involving CNS or eyes to resolve?

Back 37

2-3 days
-if fever or muscle hyperesthesia do not resolve in 3 days consider other differentials

Front 38

True or false. Cats are a common source of toxoplasmosis infection in humans.

Back 38

False, people ingest oocysts in water or working with soil or *ingest tissues containing cysts

Front 39

Toxoplasmosis infection in immunocompromises is usually acute or reactivation?

Back 39

Reactivation

Front 40

How can you prevent people from ingesting oocysts?

Back 40

Keep kids sandbox covered
Clean litterbox daily (then oocysts don't have time to sporulate)

Front 41

What are 2 ways to prevent dogs from getting infected with toxoplasmosis?

Back 41

1) Avoid coprophagia
2) Do not feed raw meat or uncooked meat byproducts

Front 42

How can you prevent cats from getting infected with toxoplasmosis? (3)

Back 42

1) Do not feed raw meat, viscera or bones
2) Do not allow cats to eat mechanical vectors (insects, earthworms)
3) Do not allow cats to roam free where they can hunt

Front 43

Is it better for a cat to test positive or negative when a pregnant woman is concerned about contracting toxoplasmosis from their cat?

Back 43

If cat tests positive then can tell owner they already have it and already eliminated oocysts, but still take same precautions as if cat was negative - wash hands etc