Parasites of the respiratory system

Question 1

How to diagnose a parasital infection of parasites…
1. at the predilection site
2. that cause systemic infection
3. that migrate

Answer 1

Question 2

Aelurostrongylus abstrusus
- species affected
- location

Metastrongylid nematodes

Answer 2

Asymptomatic, don’t cause severe respiratory disease
- cats (most severe in kittens)
- adult worms in terminal bronchioles and alveolar

adult worms up to 1cm / 10mm

Question 3

How is Aelurostrongylus abstrusus diagnosed in cats?

Answer 3

Baermann test: Detection of L1 w/ distinctive tail and spine in feces

kinked or s-shaped tail with a dorsal spine

Question 4

Pathogenesis of Aelurostrongylus abstrusus

Answer 4

eggs and worms in airway stimulate granulomatous inflammation -> may cause severe bronchitis and emphysema

clinical sign = coughing

Question 5

Eucoleus aerophilus
- hosts
- life cycle/movement of eggs

Answer 5

• mainly foxes; cats and dogs
• eggs move from bronchi/bronchioles to the pharynx -> swallowed -> passed in feces

Question 6

How is Eucoleus aerophilus diagnosed?

Answer 6

egg visualization by centrifugal fecal float

NOT A WHIPWORM (Trichuris) EGG!! whipworm eggs have more symmetrical bipolar plugs

Question 7

What are the 2 intermediate hosts of Paragonimus kellicotti (a fluke)?

Phylum: Platyhelminths
Class: Trematoda

Answer 7

Snail and crayfish

Question 8

Paragonimus kellicotti
- hosts
- location in host

Answer 8

found in lung parenchyma of wild animals (e.g., raccoons) and dogs/cats

clinical sign: coughing

Question 9

How do Eucoleus aerophilus and Eucoleus boehmi differ?

Answer 9

E. aerophilus:
- live in trachea, bronchi, bronchioles;
- coughing, dyspnea, bronchopneumonia
- dogs and cats

E. boehmi:
- live in nasal passages
- chronic sneezing, nasal discharge
- dogs only (mostly hunting dogs)

Question 10

Where do adult Ascardids live in mammals?

Answer 10

Adults live in the lumen of the small intestine with NO muccosal attachment

Question 11

Pathogenesis of Ascardids

Answer 11

• are very large
• hepatotracheal migration: eggs ingested -> mature/hatch into larve in SI -> larvae penetrate SI wall and enter systemic circ. -> reach liver and enter hepatic portal system -> reach the lungs -> coughed up and are either exit host or are swallowed again -> larvae return to SI and mature in adults
• cause mechanical damage from migration

edema, congestion, emphysema, coughing, dyspnea