Parasitology

Question 1

What do lungworms in the airway rely on to move their eggs up to the pharynx?

Answer 1

Mucociliary escalator

Question 2

What is the inflammatory response related to lungworms a reaction to?

Answer 2

The worms themselves and eggs

Question 3

Will there be an increase or decrease in clinical signs after a treatment for lungworms?

Answer 3

Increase → inflammatory response to dead worms

Question 4

What is the metastrongylid nematode parasite of cats in which the adult worms are found in the terminal bronchioles and alveolar ducts?

Answer 4

Aelurostrongylus abstrusus

Question 5

What is the often intermediate host for order strongylida?

Answer 5

Invertebrate → mollusc

Question 6

How are parasites of order strongylida diagnosed?

Answer 6

Finding larvae in feces

Question 7

What type of inflammation do A. abstrusus eggs and worms stimulate that leads to nodule formation?

Answer 7

Granulomatous inflammation

Question 8

What two conditions/diseases are resultant of the inflammatory response to A. abstrusus, presenting with clinical signs such as cough, increased breath sounds, tachypnea/dyspnea, nasal discharge, and/or sneezing?

Answer 8

Severe bronchitis and emphysema

Question 9

What is the preferred test for identifying parasitic larvae?

Answer 9

Baermann test

Question 10

Can A. abstrusus larvae be seen in a fecal floatation?

Answer 10

Yes

Question 11

What lung patterns can be seen on radiograph of cats with A. abstrusus infections?

Answer 11

Bronchial or interstitial patterns

Question 12

What is the treatment for A. abstrusus?

Answer 12

Macrocyclic lactones

Question 13

Are the enoplida Eucoleus aerophilus nematodes bigger or smaller than A. abstrusus?

Answer 13

Bigger → 20-40mm, A. abstrusus → 10mm

Question 14

How is E. aerophilus diagnosed?

Answer 14

Eggs in fecal floatation

Question 15

What are the possible treatment options for E. aerophilus?

Answer 15

Macrocyclic lactones → moxidectin specifically or fenbendazole

Question 16

What is the treatment for Cuterebra spp.?

Answer 16

Physical removal

Question 17

Systemic disease in cats with Toxoplasma gondii infections is associated with what action of the parasite?

Answer 17

Tachyzoite multiplication in tissues

Question 18

(T/F) Although Toxocara cati migrate through the lungs, it is very unlikely to see clinical signs.

Answer 18

True

Question 19

What is the fluke parasite that is found in lung parenchyma of wild animals, dogs, and cats?

Answer 19

Paragonimus kellicotti

Question 20

Is the above parasite (P. kellicotti) zoonotic?

Answer 20

Yes

Question 21

How many intermediate (maybe paratenic hosts) do P. kellicotti have?

Answer 21

Two

Question 22

(T/F) Adult P. kellicotti forms cysts in pairs in the lungs.

Answer 22

True

Question 23

How is P. kellicotti diagnosed?

Answer 23

Eggs in sedimentation fecal exam

Question 24

How is P. kellicotti treated?

Answer 24

Praziquantel or fenbendazole

Question 25

What is the Eucoleus species that is similar to E. aerophilus but lives in the nasal passages and is more commonly found in dogs?

Answer 25

E. boehmi

Question 26

Which macrocyclic lactone may be the most effective in treatment of E. boehmi?

Answer 26

Moxidectin

Question 27

What is the canine nasal mite that is transmitted directly and is typically asymptomatic?

Answer 27

Pneumonyssoides caninum

Question 28

What are the three genuses of lungworms, all of which are rare in the US?

Answer 28

Crenosoma, Filaroides, and Oslerus

Question 29

How can Strongyloides spp. cause respiratory signs?

Answer 29

Larval migration in heavy infections

Question 30

Respiratory disease is associated with what action of ascarid nematodes?

Answer 30

Larval migration through the lungs

Question 31

After a pig is infected with Ascaris suum, how long does it take for the lung damage and consequent clinical signs to appear?

Answer 31

1-2 weeks

Question 32

(T/F) A fecal float test will be diagnostic when clinical signs begin in swine infected with Ascaris suum.

Answer 32

F, prepatent period not complete

Question 33

What life stage of Ascaris suum is very difficult to kill?

Answer 33

Egg

Question 34

Is Ascaris suum zoonotic?

Answer 34

Yes

Question 35

What husbandry style is related to swine lungworm (Metastrongylus) infections?

Answer 35

Backyard, pastured pigs

Question 36

What is the recommended interval for deworming for Parascaris prophylactically?

Answer 36

Every 2 months

Question 37

(T/F) Parascaris spp. Infections are common in young horses and respiratory disease from their larval migration is also common.

Answer 37

F, dz not common

Question 38

Dirofilaria immitis are parasites of where in the body?

Answer 38

Pulmonary arteries

Question 39

What size are female D. immitis worms?

Answer 39

30 cm

Question 40

(T/F) The disease process of D. immitis involves their attachment and subsequent damage to the pulmonary arteries.

Answer 40

F, do not attach

Question 41

What are the two definitive hosts of D. immitis?

Answer 41

Dogs and ferrets

Question 42

What type of host are cats and other mammals for D. immitis?

Answer 42

Abnormal

Question 43

What is the relationship between D. immitis and Wolbachia?

Answer 43

Symbiotic → Wolbachia is required for survival and reproduction of D. immitis

Question 44

What is the prepatent period of D. immitis?

Answer 44

6 months

Question 45

What is the infective stage of the D. immitis life cycle?

Answer 45

L3

Question 46

How long can microfilaria circulate in peripheral blood?

Answer 46

1-2 years

Question 47

What is the length of patency for D. immitis worms?

Answer 47

Up to 8 years

Question 48

What group of drugs are used in treatment for D. immitis?

Answer 48

Macrocyclic lactones

Question 49

(T/F) Macrocyclic lactones kill D. immitis L4 larvae when administered at any point in the life cycle.

Answer 49

F, only prior to 60 days

Question 50

What life stage of D. immitis can you not unalive?

Answer 50

Juvenile/immature adults

Question 51

What three things does the degree of damage due to D. immitis infection depend on?

Answer 51

Worm numbers, duration of infection, and host immune response

Question 52

What lifestyle characteristic plays an important role in pathogenesis of D. immitis infections?

Answer 52

Exercise

Question 53

Is villous proliferation pathognomonic for D. immitis infections?

Answer 53

Yes

Question 54

What leads to tricuspid/right AV valve insufficiency related to D. immitis infections?

Answer 54

Increased arterial pressure

Question 55

How long can microfilaria circulate in peripheral blood?

Answer 55

1-2 year

Question 56

What occurs reflexively to the dilation of the right ventricle from the increased pressure and subsequent decreased cardiac output in D. immitis infections?

Answer 56

Compensatory hypertrophy

Question 57

What syndrome is the most severe manifestation of heartworm disease?

Answer 57

Caval syndrome

Question 58

What number of worms needs to be involved to induce caval syndrome?

Answer 58

40

Question 59

How is caval syndrome treated?

Answer 59

Surgical removal

Question 60

(T/F) Treatment and subsequent death of D. immitis worms tends to worsen the vascular damage being caused and enhance abnormal coagulation.

Answer 60

True

Question 61

The release of what (in relation to D. immitis infections) is associated with the increase of proinflammatory cytokines and a decrease of the host’s immune response?

Answer 61

Wolbachia

Question 62

Treatment of heartworm positive dogs with what drug prior to treatment with immiticide will decrease the pathologic changes associated with Wolbachia release?

Answer 62

Doxycycline

Question 63

(T/F) D. immitis microfilariae are generally not pathogenic.

Answer 63

True

Question 64

Of the diagnostic tests for D. immitis (MF detective, antigen detection, and antibody detection), which is used in cats only?

Answer 64

Antibody

Question 65

If a dog has adult worms but not circulating microfilaria, what type of infection is this?

Answer 65

Occult/hidden infection

Question 66

Though you can see microfilaria on a direct smear, what is the best diagnostic test for microfilaria detection?

Answer 66

Knott’s test

Question 67

Are false positives possible for heartworm disease?

Answer 67

Yes, non-pathogenic worm present in US that produces MF

Question 68

The antigen that is detected in D. immitis antigen tests is found in the highest amounts where?

Answer 68

Adult female worm reproductive tract

Question 69

When is annual D. immitis antigen testing especially indicated for dogs?

Answer 69

When preventatives are not used year round

Question 70

Dogs should not be tested for heartworm prior to what age?

Answer 70

6 months of age

Question 71

(T/F) ‘Heartworm preventive’ prevents heartworm infection.

Answer 71

False

Question 72

What drug class are the FDA approved heartworm preventatives that prevent development of adult worms that cause disease?

Answer 72

Macrocyclic lactones

Question 73

(T/F) Although macrocyclic lactones may kill microfilaria, they are only FDA approved to kill L3 and L4 stages up to 6-8 weeks post infection

Answer 73

True

Question 74

What is the duration of administration for doxycycline in the heartworm treatment protocol?

Answer 74

Day 1 - 28

Question 75

What should be done on day 30 in the process of heartworm treatment?

Answer 75

Administer heartworm preventative; apply mosquito repellent

Question 76

How long should you wait after your heartworm positive patient finishes their doxycycline course to administer the first melarsomine treatment?

Answer 76

1 month, day 61

Question 77

When is the second melarsomine treatment done?

Answer 77

1 month after the first treatment; day 90

Question 78

When is the third melarsomine treatment done?

Answer 78

1 day after the second treatment; day 91

Question 79

When should a knott's test be performed after the third melarsomine treatment?

Answer 79

1 month; day 120

Question 80

What should be done if the above knott’s test is positive? (When should a knott's test be performed after the third melarsomine treatment? (1 month; day 120) )

Answer 80

Treat with microfilaricide and retest in 4 weeks

Question 81

When should an antigen test be performed after the third melarsomine treatment?

Answer 81

9 months; day 365

Question 82

What should be done if the above antigen test is positive? When should an antigen test be performed after the third melarsomine treatment? (9 months; day 365)

Answer 82

Retreat with doxycycline followed by two doses of melarsomine 24 hours apart

Question 83

What is the protocol for the not FDA approved non-arsenical adulticide treatment?

Answer 83

Doxy for 4 week period, monthly oral ivermectin until no appreciable disease on testing, antigen and MF testing every 6 months

Question 84

(T/F) Exercise restriction is only applicable to arsenical heartworm treatment.

Answer 84

F, all hw treatments

Question 85

Why are cats considered abnormal hosts for D. immitis?

Answer 85

Do not effectively support transmission

Question 86

How do D. immitis infection related clinical signs differ in cats compared to dogs?

Answer 86

Cats - respiratory signs; dogs - circulatory signs

Question 87

(T/F) Knott’s tests are used in the diagnosis of heartworm in cats.

Answer 87

F, cats rarely have MF

Question 88

(T/F) Macrocyclic lactones are used as preventative in cats just as in dogs.

Answer 88

True