Respiratory Pathology Lecture 2 Flashcards
What are two viral infectious causes of rhinitis in horses
- Equine influenza
- Equine viral rhinopneumonitis/ equine herpes viruses 1 and 4
What are some mild signs of equine influenza
Serous nasal discharge, fever, and conjunctivitis
What industry is equine influenza especially a concern in
Race industry- respiratory distress
How does equine viral rhinopneumonitis/ equine herpes viruses 1 and 4 affect foals
Mild respiratory disease
How does equine viral rhinopneumonitis/ equine herpes viruses 1 and 4 affect mares
Myeloencephalopathy and abortions
Herpes virus can remain latent in ___, become reactive during time of __ and ___ and undergo ___ transmission to susceptible host
Trigeminal ganglia, stress, immunocompromised, Aerogenous
What is the guttural pouch
Large air filled diverticula on the ventral portion of the Eustachian tubes in horses
What are some important structures in the guttural pouch
Internal and external carotid arteries, maxillary artery. CN VII, IX, X, XI, and XII
Atlanto-occipital joint
Strangles/ Streptococcus equi affects what age group
Young horses
What is the pathogenesis of strangles/ Streptococcus equi
- Aerogenous infection of nasopharyngeal mucosa
- Lymphatic vessels
- Mandibular and retropharyngeal LN
- Suppurative rhinitis and lymphadenitis
- Clinical signs: cough, nasal discharge, conjunctivitis, swollen lymph nodes
Young Horse presents with suppurative rhinitis and swollen lymph nodes. What is your concern
strangles
What are some sequela of strangles
- Bastard strangles
- Bronchopneumonia
- Laryngeal hemiplagia
- Dysphasia
- Facial paralysis
- Horners syndrome
- Purpura hemorrhagica
- Guttural pouch empyema +/- chondroids
What is bastard strangles and how does it spread
Hematogenous spread
Abscess formation in organs throughout the body
Often fatal-systemic spread
What nerve compression and atrophies can result from strangles
- Recurrent laryngeal nerve—> laryngeal hemiplegia
- Vagus and glossopharyngeal—> dysphagia
- SNS nerves—> facial paralysis and horners
What does horners syndrome look like
Miosis, partial ptosis, and elevated third eyelid
What is purpura hemorrhagica
Streptococcus equi antigen-antibody complexes form in the small vessels in skin and mucosa causing vasculitis
What type of hypersensitivity reaction is purpura hemorrhagica
Type III
what is wrong and what can be the cause
Guttural pouch pus- empyema
Caused by strangles
What wrong here and what is a potential cause
empyema with chondroids
Cause: strangles
What is wrong here and what is causative agent
guttural pouch mycosis
Cause: aspergillus fumigatus
How can you grossly tell difference between guttural pouch mycosis and guttural pouch empyema
Mycosis appears more necrotizing and hemorrhagic, whereas empyema is more yellow pus
What are some possible sequela to guttural pouch mycosis
- Epistaxis
- Thrombosis of a carotid artery—> cerebral infarcts
- CN deficits
What is wrong here
mycosis with hemorrhage
Where do nasopharyngeal polyps form
Middle ear to Eustachian tube and nasopharynx or external ear canal
What is a nasopharyngeal polyp composed of
Mildly inflamed fibrovascular stroma covered by squamous or pseudostratified epithelium
What species are nasopharyngeal polyps common in
Most common in cats, also seen in horses
Nasopharyngeal polyps are associated with what 3 problems
- Chronic rhinitis
- Sinusitis
- Otitis media
what is wrong
Nasopharyngeal polyp
What non-neoplastic space occupying mass do horses get in the nasal cavity
Ethmoid hematomas
How do horses with ethmoid hematomas present
Unilateral epistaxis
What is wrong
Ethmoid hematoma