Respiratory 3 Flashcards
What are 4 canine cough differentials? (there are 6 total)
- Infection
- Heart disease
- Allergies
- Tonsillitis/sore throat
- Collapsing trachea
- Neoplasia
What are some examples of infectious agents that should be on your differential list for a coughing canine?
Bordetella, parainfluenza, adenovirus-2 (Kennel cough)
Distemper (Pneumonia)
Filaroides osleri
Blastomyces (Fungal infection)
In addition to canines, collapsing tracheas can occur in what 3 other species?
Horses
Goats
Cattle
- Where is the most likely spot for the trachea to collapse?
- What type of an environment increases the risk of developing a collapsing trachea?
- In what age group of animals does tracheal collapse most commonly occur?
- At the thoracic inlet
- Household with smokers increases risk
- Typically in middle aged to older animals
- What is normal post mortem tracheal width to height ratio?
- What is tracheal width to height ratio with collapsing trachea?
- Normal = 1 : 1
- Collapsing trachea = 4+ : 1
With a collapsing trachea…
- Which part of the trachea collapses on inhalation?
- Which part of the trachea collapses on expiration?
- Cervical trachea collapses on inhalation
- Thoracic trachea collapses on expiration
Fill in the missing words of the pathogenesis for collapsing trachea:
C-shaped cartilagenous rings weaken –> rings flatten out –> the dorsal tracheal membrane stretches, becoming _______ –> the trachea collapses under _______ pressure –> collapse leads to mucosal irritation with increased _______ and inflammation –> cough
C-shaped cartilagenous rings weaken –> rings flatten out –> the dorsal tracheal membrane streatches, becoming wider –> the trachea collapses under negative pressure –> collapse leads to mucosal irritation with increased secretion and inflammation –> cough
A 2 year old male Bull dog presents for (1) snorting while breathing, (2) snoring in his sleep, (3) sleeping on his back, (4) and occasionally turinging blue and collapsing during exercise.
What is a likely diagnosis based on the signalment and the history?
Brachycephalic airway syndrome
In addition to the English Bulldog, what are 3 other dog breeds that are prone to the heritable condition of Brachycephalic airway syndrome?
Pug
Perkingese
Boston Terrier
List as many clinical signs of the bradycephalic airway syndrom as you can!
(There are 9 provided)
- Loud snoring
- Coughing
- Gagging
- Syncope (fainting)
- Episodes of collapse
- Difficulting eating
- Stertorous breathing (heavy snoring or gasping sound)
- Exercise intolerance with cyanosis
- Sleeping on their back
- What are the 3 primary anatomic components of bradyceophalic airway syndrome?
- What are the 3 secondary components that develop as a result of the increased respiratory effort?
- Elongated soft palate
- Stenotic nares
- Hypoplastic trachea
- Everted laryngeal saccules
- Everted tonsils
- Laryngeal collapse
This is tissue from a dog with a chronic cough for 2 years.
What is your diagnosis?
Collapsing trachea
- What abnormality do you notice?
- What disease process is this a component of?
- In what percentage of these cases would you likely see this abnormality?
- Stenotic nares
- Collapsing trachea
- 77%
- What do you call this abnormality?
- What disease process is this change associated with?
- Elongated soft palate (the tip of the soft palate has protruded into the airway and interfered with inspiration of air into the lungs)
- Collapsing trachea
This is tissue from a dog:
- What is your diagnosis for the diffusely mottled area of lung in the image?
- What is your diagnosis for the dark red anteroventral lung in the image?
- Intersitial pneumonia
- Bronchopneumonia
This is tissue from a dog that presented with the following symptoms:
Mild to moderate fever
Oculonasal discharge
Vomiting and diarrhea
Cough, labored breathing
Ataxia
Hyperesthesia (increased sensitivity to stimuli)
Deteriorating mental and motor skills
- What do you call the object circled in red?
- What are the objects circled in yellow?
- What is an infectious agent associated with the object circled in red?
- Red = eosinophilic, intracytoplasmic inclusion body
- Yellow = neutrophils
- Canine distemper virus
- Canine distemper virus is immunosuppressive and causes necrosis of what?
- That necrosis disrupts respiratory defenses, predisposing an animal to what?
- Pneumocytes, bronchiolar macrophages, and alveolar macrophages
- Bacterial bronchopneumonia
If an unvaccinated animal presents to you with a combination of GI, respiratory, and neurologic signs, what should be a top differential?
Canine distemper virus
Complete the pathogenesis of canine distemper virus:
Unvaccinated dog –> exposed to canine distemper virus –> viremia –> spreads to the epithelium of the ___?___, ___?___, ___?___, and central nervous system.
Unvaccinated dog –> exposed to canine distemper virus –> viremia –> spreads to the epithelium of the RESPIRATORY, GASTROINTESTINAL, UROGENITAL TRACTS, and the central nervous system.
Complete the pathogenesis for Blastomyces in a dog:
Fungus grows in the soil –> conidia are inhaled –> ___A___ –> hematogenous & lymphatic dissemination –> ___B___ –> macrophages release cytokines –> recruite additional inflammatory cells into the interstitium –> ___C___
A. Fungus becomes a yeast at elevated temperature of host
B. Systemic blastomycosis
C. Interstitial pneumonia
What are the following cell types:
Yellow?
Green?
Red?
Yellow = macrophage
Green = PMNs
Red = Blastomyces
Which type of dogs are most at risk for Blastomyces infection?
Large, male, hunting dogs
1-5 years of age
This is tissue from a dog with the following clinical signs:
Pyrexia
Weight loss
Lethargy, depression
Dyspnea
Tachypnea
Bilaterally diminished lung sounds
Marked abdominal breathing
Non-productive cough
- Describe this lesion.
- What is your morphologic diagnosis?
- What is the causative agent?
- Gross description: lungs are dark, wrinkled, moderatly collapsed, but spongy; thoracic cavity contains abundant thick, opaque, red-colored fluid with small yellow flecks (sulfur granules)
- Pyogranulomatous and hemorrhagic pleuritis
- Nocardia asteroides
Whar are 4 causes of pleuritis? (There are 6 provided)
- Migration down fascial planes of the neck
- Penetrating wound through the thoracic wall
- Inhalation and/or migration of a foreign body
- Rupture of an infectious focus in the chest
- Hematogenous spread
- Intra-thoracic esophageal perforation
There are 5 common causes of chronic nasal discharge in the dog, can you name 3 of those 5?
- Neoplasia
- Fungal sinorhinitis
- Nasal foreign body
- Rhinitis secondary dental disease
- Idiopathic lymphoplasmacytic rhinitis (allergic rhinitis)
Notic the destruction and proliferation of the nasal turbinates in this dog. On biopsy there was a suppurative and necrotizing rhinitis with intralesional fungi.
- What is your diagnosis?
- What is the typical causative agent?
- Nasal aspirgillosis
- Aspergillus fumigatus
This is tissue from a dog who presented with the following clinical signs:
Chronic unilateral nasal discharge (purulent to blood-tinged)
Mild to moderate but transiet response to antibiotics
Facial asymmetry
Recently had 5 seizures over the course of 48 hours
- Describe the lesion and give a diagnosis.
- Why the transient response to antibiotics?
- Why the neurologic signs?
- Uniform, tan-colored mass in the nasal cavity & cranial vault = nasal adenocarcinoma
- Space occupying mass prevents nasal drainage –> secondary infection
- Tumor infiltrated through the cribiform plate –> bacterial meningitis or tumor directly impacting the brain –> seizures
This is an x-ray of a dog with the following clinical signs:
Decreased heart and lung sounds
Progressive breathing problems, with cough
Loss of appetite
NO fever
X-ray findings:
Fluid in the chest cavity
Right middle lung lobe appears enlarged and dense
Chest tap:
Abundant serosanguinous fluid removed
- What is your diagnosis?
- What would this look like grossly?
- Lung lobe torsion
- Torsed lung would be dark red to black in color due to consolidation of blood (see image)
Complete the following pathogenesis for a lung lobe torsion?
Torsion –> muscular artery continues to pump blood into the lobe but vein collapses –> ___A___ –> infarction –> ___B___ –> serosanguinous thoracic effusion –> ___C___ –> respiratory distress
A. Venous congestion
B. Serosanguinous fluid leaks from necrotic lung
C. Atelectasis
- Which lung lobe is most commonly affected in a lung lobe torsion?
- Lobe torsions typically occur at the level of what?
- Right middle lung lobe is most commonly affected
- Lobe typically twists at the level of the base of the heart
This is tissue from a pig:
(Hx: suckling pigs have been sneezing, snuffling, and have a nasal discharge. Older pigs have tear-stained skin beneath the eyes and malformations of the nose, including twisting and shortening of the snout, as well as decreased growth)
- What is your diagnosis?
- What is a common phrase for this condition?
- What are 2 common causative agents of this disease process?
- Atrophic rhinitis (with moderate deviation of the median septum)
- AKA “Shotgun snout”
- Bordetella bronchiseptica & Pasteurella multocida type D
Complete the following pathogenesis for atrophic rhinitis in a pig:
Bordetella bronchiseptica colonizes nasal epithelium –> rhinitis –> ___A___ –> elaboration of cytotoxins which disrupt osteogenesis of the turbinate bone –> ___B___
A. Toxigenic Pasteurella multocida type D colonizes damaged nasal mucosa
B. Atrophic rhinitis
In a pig, what type of disease process is this patchy, lobar consolidation pattern suggestive of?
Swine influenza
Complete the following pathogenesis for Mycoplasma hyopneumoniae in a pig:
Mycoplasma binds to cilia –> ___A___ –> clumping and loss of cilia –> ___B___
A. Ciliostasis
B. Loss of airway epithelial cells
- How does a lung infected with Mycoplasma hyopneumoniae look grossly?
- What would the clinical signs typically be with a Mycoplasma hypopneumoniae infection?
- Mild & patchy with anterior ventral consolidation
- Minimal - often not clinically ill
- What are the clinical signs associated with an enzootic pneumonia in pigs?
- What would their lungs look like grossly?
- Clinical signs = chronic, sporadic, nonproductive cough with decreased weight gain
- Well-demarcated, tan-colored, with anteroventral consolidation (see image)
Complete the following pathogenesis for enzootic pneumonia in a pig:
Mycoplasma hyopneumoniae colonizes the respiratory epithelium –> ___A___ –> loss of cilia –> ___B___ –> decreased mucociliary clearance –> ___C___
A. Ciliostasis
B. Decreased epithelial cells & goblet cells
C. Bacterial bronchopneumoniae
Good pig…
Found dead…
Blood coming from nose…
What is you diagnosis??
Actinobacillus pleuropneumonia (APP)
What is your most likely causative agent involved here?
Actinobacillus pleuropneumoniae
- What type of morphologic diagnosis would be consistent with an APP infection?
- List 3 gross characteristics of a lung infected with APP.
- Hemorrhagic necrotizing pleuropneumonia
- Gross characteristic on necropsy:
- Focally intense fibrinous pleuritis
- Areas of necrosis
- Areas of hemorrhage
- Typically unilateral
- Typically begins in the region of the hilus
Complete the following pathogenesis for APP –> No disease:
___A___ –> colonizes squamous epithelium of tonsil & upper respiratory tract –> ___B___ –> NO DISEASE
A. APP inhaled
B. Mucociliary apparatus prevents APP from reaching the lower respiratory tract
Complete the following pathogenesis for APP –> Pleuopneumonia:
APP inhaled –> colonizes squamous epithelium of tonsil & upper respiratory tract –> ___A___ –> APP reaches alveoli –> ___B___
A. Mucociliary apparatus damaged by SIV or Mycoplasma hyopneumonia
B. Pleuopneumonia
Complete the following pathogenesis of APP –> Pleuropneumoniae:
APP inhaled –> colonizes squamous epithelium of tonsil & upper respiratory tract –> ___A___ –> ___B___ –> pleuropneumoniae
A. Outbreak of disease with aerosolation of massive numbers of organisms
B. APP reaches the alveoli
True or False:
Actinobacillus pleuropneumoniae will NOT typically cause disease without some form of impairment to the mucociliary apparatus.
TRUE
- What is this change called?
- What is the causative agent?
- Explain what is occuring to cause this change.
- “Streaming leukocytes”
* Actinobacillus pleuropneumoniae* - Bacteria produce a leukotoxin which causes degeneration and necrosis of leukocytes
Lungs are diffusely tan, mottled, heavy, rubbery, and non-collapsing.
- What is your morphologic diagnosis?
- What are 4 causes of this in pigs?
- Diffuse interstitial pneumonia
- PRRS virus (porcine reproductive & respiratory syndrome virus
- PCV2 (porcine circovirus type II)
- Salmonella choleraesuis septicemia
- Ascarid larval migration
The following refer to swine cases:
- Interstitial pneumonia + enlarge iliac lymph nodes = ?
- Interstitial pneumonia + enlarged spleen + enlarged, hemorrhagic lymph nodes = ?
- Interstitial pneumonia + pigs moved from slatted floors to a dirt lot = ? (milk spots in the liver)
- PRRS virus or PCV2
- Salmonella choleraesuis septicemia
- Ascarid larval migration
This is tissue from a pig who became rapidly depressed, had an elevated temperature, stopped eating and died. Additoinal herd problems include (1) occasional neurologic signs and (2) occasional swollen joints & lameness.
- Describe the lesion.
- What is the likely causative agent?
- What is the name of this disease?
- Diffuse fibrinous pleuritis and pericarditis
- Haemophilus parasuis
- Glasser’s disease
Complete the following pathogenesis of Haemophilus parasuis –> polyserositis:
Aerosol exposure to a new strain (mixing nursery pigs) –> ___A___ –> bacteremia –> ___B___ –> polyserositis (pleuritis, pericarditis, peritonitis)
A. colonizes nasal cavity
B. seeds serosal surfaces
Complete the following pathogenesis of Haemophilus parasuis –> arthritis:
Aerosol exposure to a new strain –> colonizes nasal cavity –> ___A___ –> ___B___ –> arthritis
A. bacteremia
B. seeds joints
Complete the pathogenesis of Haemophilus parasuis to meningitis:
Aerosol exposure to new strain –> colonizes nasal cavity –> bacteremia –> ___A___ –> ___B___
A. seeds meninges
B. meningitis
- What type of morphologic diagnosis would be consistent for a lung infected with swine influenza?
- Damage to the mucociliary apparatus (notice flattening of the epithelium in the image) then could predispose the animal to what?
- Necrotizing & suppurative bronchiolitis (image)
- Secondary bacterial pneumonia
This is tissue from a dog:
(Hx: mild fever, visual difficulties, anorexia, weight loss, non-healing draining skin lesion on right paw, depression, decreased stamina, persistent cough, and shortness of breath)
- Describe the lesion.
- What is your morphologic diagnosis?
- What is a likely causative agent?
- Lungs: are diffusely heavy, rubbery, non-collapsing and exhibit a diffuse miliary pattern with cream-colored foci alternating with red regions (Interstitial pneumonia); Lymph nodes: tracheobronchial lymph nodes are enlarged (Arrow)
- Pyogranulomatous interstitial pneumonia
- Blastomyces dermatitidis
