9 – Pneumonia (Dog, Cat, Horse)

Question 1

Kennel cough

Answer 1

• Bordetella bronchaseptica with a virus
  o Tracheitis
  o Atrophic rhinitis

Question 2

Bordetella bronchoseptica in kennel cough is often associated with

Answer 2

• Virus
  o Canine adenovirus 2
  o Canine parainfluenza virus

Question 3

Bronchopneumonia in dogs

Answer 3

• NOT common in dogs
• (don’t need to remember bacteria)
• May result in outbreaks
• Secondary cause (immunosuppression or viral infections)
• More hemorrhage in cranial portion of lungs

Question 4

Aspiration pneumonia vs. bronchopneumonia in a dog

Answer 4

• Aspiration pneumonia:
  o Colour change
  o More likely UNILATERAL
• HISTORY: under anesthetic recently?

Question 5

Canine distemper

Answer 5

• *canine distemper virus
• Effects a wide range of species (ferrets!, wildlife species (racoons, skunks, seals)
• Infection occurs via INHALATION
• Causes bronchointerstitial pneumonia
  o Diffusely wet, firmer, failed to collapse
  o Cranio-ventral portion darker red
• More common in rescue and stray dogs

Question 6

Canine distemper causes/signs

Answer 6

• Immunosuppression
• Nasal discharge
• Coughing
• Dyspnea

Question 7

Canine herpes (Herpes virus)

Answer 7

• VIREMIA in young puppies
• *Interstitial pneumonia
• Diffusely effected
• Heavy, wet, red
• Slight rib impressions

Question 8

Acute respiratory distress syndrome (dogs) (clinical term rather than a specific disease)

Answer 8

• Hyaline membranes=bright pink histologically
  o Associated with MASSIVE ACUTE damage to alveolar epithelium
  o Large amounts of high protein edema fluid in the alveoli
• Severe hypoxia without L. atrial hypertension
• Many causes (use HISTORY: secondary to other conditions)
• Lungs heavy, wet, red, firm

Question 9

Blastomyces and pulmonary neoplasia (dogs)

Answer 9

• Look the same
• Use geographical location
• *differentials for each other!

Question 10

Blastomyces (dogs)

Answer 10

• Most common one in dogs (often die as a result)
• *yeast (blatomyces dermatidis)
  o Distribution is geographical (S. SK, S. MB: hunting or farm dogs)
• Multifocal, granulomatous pneumonia with soft white nodules (not metastatic neoplasia)
• Looks like embolic pneumonia, but caused by inhalation of organisms
• *always CHRONIC INFECTIONS

Question 11

Pulmonary neoplasia (dogs)

Answer 11

• Older dog, not from S. SK
• Adenocarcinomas (and alveolar carcinomas) most common
• Likely malignant from somewhere else (widespread)

Question 12

Lung lobe torsion (dog)

Answer 12

• ACUTE onset of respiratory distress
• Variation in which lung lobe is twisted
  o R. middle lobe in large dogs
  o L. cranial lobe in pugs
• Heavy, wet, congested
• Unclear cause: something that leads to a more mobile lobe (consolidation or atelectasis)

Question 13

Bronchitis/asthma (cats)

Answer 13

• Chronic constant: bronchitis
• Chronic intermittent: asthma
• Lots of eosinophils
  o Hypersensitivity reaction=swelling in walls of airways and hypersecretion of mucous
• Airways obstructed with mucous and inflammatory exudate within lumen

Question 14

Bronchopneumonia (cats)

Answer 14

• Uncommon
• Secondary to viral infection
  o Pasteurella multocida
  o Bordetella bronchiseptica

Question 15

Toxoplasma Gondii (cats)

Answer 15

• Parasitic disease that causes diffuse interstitial pneumonia
  o Red, wet, heavy lungs that fail to collapse

Question 16

Aelurostrongylus abstrusus (lungworm) (cats)

Answer 16

• Multifocal, dark red, soft nodules (maybe more on dorsal side?)
• History! (outside cats)
• Not common of bacterial or viral infections

Question 17

Paragonimus Kellicotti (cats)

Answer 17

• Fluke in lungs of cats (from crayfish)
• Outside cats
• Individual soft nodules (could be confused with neoplasia)
• Rupture of cyst=great damage or pneumothorax

Question 18

Cats with pulmonary tumours

Answer 18

• More than in dogs
• Adenocarcinomas
  o Metastasis to digits=‘lung digit syndrome’ (first clinical sign)
   Sores on their feet
• *can also happen in people
• Metastatic neoplasms to lung are frequent

Question 19

Heaves (COPD, recurrent airway obstruction)

Answer 19

• Hypersensitivity reaction
  o Dirty environment
• Changes to bronchioles=inflammation, hypertrophy, metaplasia of goblet cells
  o Airway epithelium=more goblet cells than expected (=more mucous)
  o Increased respiratory effort
• Heave line: hypertrophy of muscles associated with breathing

Question 20

Heaves: damage to bronchioles where there is

Answer 20

• Neutrophilic and lymphocytic inflammation in walls and lumen
• Smooth muscle hypertrophy in bronchiole walls
• Goblet cell metaplasia

Question 21

Rhodococcus equi (horse)

Answer 21

• Soil bacterial infection
• Sporadic disease and rare outbreaks in 2-6month olds
• Cough, depression, weight loss, fever
• *cranioventral abscess formation in lungs
  o May also form in bronchial lymph nodes

Question 22

Pleuropnemonia (horse)

Answer 22

• Usually extension of bronchopneumonia into pleural cavity
• Inflammation of pleura and of the lung beneath
• Produce large amounts of fibrin
• More common in young horses

Question 23

Pleural fluid in pleuropneumonia (horses)

Answer 23

• Very abundant
• Foul smelling with fibrin clots (eventually adhesion formation)

Question 24

Dictyocaulus arnfieldi (horse)

Answer 24

• Nematodes whose natural host=donkey
• Disease occurs in horses
  o Worms found within caudal bronchi

Question 25

Exercise induced pulmonary hemorrhage (horses)

Answer 25

• Bleeding from lungs during exercise
• *bleeding from noses 30-90mins after exercise=most common clinical sign
  o Can cause death
• More associated with racing breeds
• Unclear cause (maybe high pulmonary pressure and changes in vascular walls)

Question 26

Disease of immunosuppression in horses

Answer 26

• Pneumocystis carinii
• Adenovirus