resp 4 lectures

Question 1

how can pulmonary neoplasia cause issues (in cats)? what issues?

Answer 1

• progressive dyspnea > occupying space within lung tissue
• compression of a vital structure > eg. tumor compresses airway > chronic cough
• also more systemic effects > inflammatory cytokines > cachexia, malaise
• metastasis….
• diffusion from tumour > pulmonary edema, or pleural effusion resulting in clinical signs

Question 2

cat pulmonary carcinoma
- how common?
- significacne?
- possible lesions?

Answer 2

• not super common in cats compared to other neoplasias, but not rare
• in cats, pulmonary carcinomas are almost always malignant tumors, that metastasize within lungs, invade pleura, go to many sites in the body
  > classic site is the footpad of the digit > lameness

Question 3

expected clinical signs from lung lobe torsion?
- appearance?

Answer 3

• lobe heavier than normal (presence of tumour eg?) > torsions (can be other causes too, eg. inflammatory lesions, etc.)
  > pleural effusion is common
  > venous infarction due to twisting > occlusion > effusion

Question 4

Cats:
Sneezing, nasal discharge + oral ulcers =
- what does this point to?

Answer 4

• calicivirus infection
  > upper resp, occasionally can get primary viral pneumonia, but usually secondary bacterial

Question 5

cats Chronic rhinitis:
- pathology of why this can happen? pathogens?

Answer 5

• excavation of nasal turbinates
  > herpes virus can do this very commonly > only destroys the epithelium but can be secondary loss of turbinates
  > they cannot regrow > permenant impairment of resp defences

Question 6

Why Do Feline Upper Respiratory Tract Infections Become Chronic??

Answer 6

• Recrudescence from latency—herpesvirus * Persistent infections: calicivirus, Bordetella
• Destruction of epithelium or turbinates
• Post-inflammatory scarring and stenosis
• Hidden focus of infection: sinusitis
• FeLV, FIV

Question 6

Which is more important in bacterial pneumonia of cats compared to that of dogs?
a. Predisposing viral infections
b. Bordetella, Pasteurella, Streptococcus, …
c. Aspiration pneumonia

Answer 6

all of them can happen but:
a. Predisposing viral infections
- very common reason for cats to get pneumonia, less common in dogs
> dog cases are often aspiration related

Question 7

Feline bronchitis
1. Reasons for airway obstruction?
2. Functional effects of airway
obstruction?
3. Expected clinical signs?

Answer 7

• common disease
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• inflammation/ edema, exudate and necrotic debris, bronchoconstriction
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• Increased resistance to airflow through the airways
• Increased respiratory effort (dyspnea)
• Failure to ventilate the alveoli, thus leading to hypoxemia and hypercapnia.

Question 8

Aelurostrongylus abstrusus (cats)
* Source of infection?
* Are worms grossly visible?
- lesions
* Clinical significance?
What parasite of sheep and goats does this remind you of ?

Answer 8

• outdoor young cats
  > access to the snail or slug intermediate hosts
• microscopic worms
  > soft 2-5 mm diameter nodules beneath the pleura of the dorsal lung
  > granulomatous inflammatory response
• usually subclinical
• DDx metastatic neoplasia esp in older animal
  <><><><>
  Muellerius capillaris

Question 9

PARAGONIMUS KELLICOTTI (cats)
- from who?
- lesions
- clinical significance?
- also in who?

Answer 9

• crayfish intermediate host
• cyst-like cavitations in the lung
• usually no clinical signs, But:
  infection can be significant in two ways:
• The cyst can be mistaken radiographically for a neoplasm, leading to unnecessary euthanasia.
• Rupture of the cysts causes pneumothorax with acute dyspnea.
• also in dogs

Question 10

Are nasal biopsies useful?
- when yes? when no?

Answer 10

• often dont get back specific or useful information…
• they are good when you can actually find the lesion and biopsy it… sometimes can be useful by chance
  <><><><>
  Yes:
• Neoplasia
• Nasal polyps
• Aspergillosis
• Allergic–eosinophils are suggestive > need to look at this in context of clinical findings (can be adjacent to fungal lesions, neoplasms)
• “Lymphoplasmacytic rhinitis” ??? > non-specific pathological lesion, any of these can cause it. But if we can ule others out, this may respond to corticosteroid therapy, even though lesion not specific
  <><><><>
  Not really:
• Foreign body–observed by endoscopy
• Trauma–radiographs
• Tooth root abscess – clinical exam, radiographs
• Oronasal fistula – clinical exam
• Allergic
  > all of these are not diagnosible by biopsy, up to the clinicial
  <><><><><>
• in over half, maybe over 80%, will get a diangosis that may not be helpful, but can get useful info in a subset of cases…

Question 11

NASAL CRYPTOCOCCOSIS
- who?
- lesion
- impact?

Answer 11

• cats, less commonly dogs, other mammals
• thick capsule that invokes very little inflammation, so the gross lesions appear as a gooey gelatinous mass of yeast bodies
• inhalation, leading to nasal disease
• can invade from the nasal cavity through the cribriform plate to cause meningoencephalitis
• Aspiration of infected nasal mucus may cause pneumonia.
• In immunosuppressed individuals, hematogenous spread results in ulcerating cutaneous nodules, uveitis, or lesions in the viscera.

Question 12

AUDITORY POLYP
- who
- what? where? lesion and effects?

Answer 12

• Auditory (nasopharyngeal) polyp is a common condition in young adult cats
• middle ear or auditory (Eustachian) tube
• grows into the pharynx to cause gagging or dysphagia, or into the nasal cavity to cause stertor and nasal discharge, or into the middle ear to cause head tilt, head shaking, or Horner’s syndrome.
• It is important to distinguish this common condition of young cats from neoplasia.

Question 13

Diffuse interstitial pneumonia in pigs, pathogens:

Answer 13

1. PRRS
2. Porcine circovirus
   (3. Swine influenza)
   - septicemia

Question 14

Cranioventral bronchopneumonia in swine, pathogens

Answer 14

(3. Swine influenza)
4. Mycoplasma hyopneumoniae
5. Opportunistic bacterial pneumonia (Pasteurella & others)

Question 15

Bronchopneumonia: middle/caudal lobe, fibrinonecrotic in swine- pathogen

Answer 15

Actinobacillus pleuropneumoniae

Question 16

Enzootic nasal tumour - sheep, goats
- cause

Answer 16

• caused by retrovirus
  > result in stridor or stertor

Question 17

septicemia in small ruminants, pathogens

Answer 17

mannheimia haemolytica, bibersteinia trehalosi

Question 18

Maedi visna in goats and sheep, disease

Answer 18

• slow virus
• chronic progressive disease
• at least 2 years of age when we see signs in sheep
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• kids can develop lung disease
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• interstisial pneumonia

Question 19

Muellerius capillaris

Answer 19

• nodules, most common in dorsocaudal portion of lung
• no clinical disease in sheep
• clinical signs more common in goats due to heavier burdens