55- Resp System Upper Resp Tract Conditions

what are the body parts of the upper resp tract?

nasal cavity, pharynx, guttural pouch, larynx, trachea

dilation of mucosal vessels (congestion) indicates what

circulatory failure preceding death

epistaxis

blood flow from nose (nasal mucosa or from deep in lungs)

whats unilateral epistaxis from

upper resp tract

whats bilateral epistaxis from

lungs

causes of epistaxis

local trauma, submucosal erosions from inflammation, neoplasia

specific form of pulm hemorrhage in racehorses that occurs after exercise and is characterized by epistaxis in severe cases

exercise induced pulmonary hemorrhage

gross lesion: large areas of dark brown discoloration on caudal lung lobes

exercise induced pulmonary hemorrhage

common pathogens of the guttural pouch

fungus, bacteria

why is infection of the guttural pouch bad?

doesnt drain well, close to carotid arteries and cranial nerves

whats guttural pouch mycosis caused by

inhalation of moldy hay

ASPERGILLUS

horse presents with dorsal and lat walls of gut pouch mucosa covered by focal rounded raised plaques that coalesce into larger masses, unilateral

guttural pouch mycosis

histo: necrotic inflamm of the mucosa with vasculitis and intralesional fungal hyphae

gut pouch mycosis

empyema

accumulation of neutrophils within a potential space

what is gut pouch empyema a sequela to

suppurative inflamm of the nasal cavities from strep equi infection aka strangles !!

what is diff about the secondary lesions of gut pouch empyema

similar to gut pouch mycosis but no erosion of internal carotid artery

when does infectious rhinitis occur

secondary to changes in microbiota balance of the nasal cavity and normally resolves completely

chronic rhinitis

destruction of nasal conchae and deviation of the septum

sequela to infectious rhinitis

hemorrhage, ulcers, nasopharyngeal polyps arising from inflamed mucosa

infectious rhinitis in the facial bones could cause

osteomyelitis

infectious rhinitis in the cribiform plate could cause

meningitis

infectious rhinitis in the eustachian tubes could cause

otitis media or gut pouch empyema in horses

infectious rhinitis in the inner ear could cause

otitis interna and vestibular syndrome

gross lesion: mucosal hyperemia, increased prod of clear fluid manufactured by serous glands present in the nasal submucosa

serous rhinitis (milldest form)

causes of serous rhinitis

mild irritants, cold air, early viral infections, upper resp system infections, mild allergic rxns

gross lesion: serous and mucus discharge, mucus exudate is THICK translucent or kinda turbid viscous fluid

catarrhal rhinitis

histo: mucus gland hyperplasia (inc goblet cells)

catarrhal rhinitis

describe the acute inflamm process of suppurative rhinitis

neutrophilic exudate occurs when the nasal mucosa suffers a more severe injury

• sometimes includes mucosal necrosis and secondary bacteria infection

gross lesion: thick and opaque exudate that is white/green/brown, nasal passages are obstructed by exudate, and possibly mucosuppurative if features of catarrhal inflamm

suppurative rhinitis

inflammation that causes increased vascular permeability, resulting from abundant plasma fibrinogen which forms FIBRIN

fibrinous rhinitis

gross lesion of fibrinous rhinitis

fibrin appears as a yellow tan or gray friable mat on the nasal mucosa

fibrinous rhinitis: if the fibrin mat is fibrinous =

thin film of exudate

fibrinous rhinitis: if the fibrin mat is pseudodiphtheritic rhinitis =

fibrinous exudate can be removed leaving an intact underlying mucosa

fibrinous rhinitis: if the fibrin mat is diphtheritic or pseudomembrane rhinitis =

pseudomembrane is difficult to remove and leaves an ulcerated mucosa

gross lesion: multifocal to coalescing tan granulomas, chronic inflamm can lead to the formation of polypoid nodules that can obstruct nasal passages

granulomatous rhinitis

histo of granulomatous rhinitis

infiltration of epitheloid macrophages mixed with a few lymphocytes and plasma cells

what is granulomatous rhinitis associated with

chronic allergic inflammation and infectious etiologies like fungi or tuberculosis

most common causes of tracheitis are ?

VIRAL infections like infectious bovine rhinotracheitis, equine viral rhinopneumonia, canine distemper, feline rhinotracheitis

with tracheitis, viral lesions are typically mild but become complicated with

secondary BACTERIAL infections and can lead to tracheal ulceration

what is seen after aspiration, inhalation of fumes during fire, aspiration of food or grass awns

tracheitis

what occurs freq with rhinitis

sinusitis

what can cause sinutitis

sequela to penetrating object or septic wounds of nasal, frontal, maxillary, palatine bones

improper dehorning

max tooth infection

whats this pic show

sinusitis

dog presents with acute onset coughing and has rhinitis/pharyngitis but also was normal prior

canine infectious resp disease complex

pathogenesis of CIRD involves mult pathogens like

CAdV-2, bordetella, strep zoo

severity increases with mult pathogens and poor ventilation

gross lesions: CATARRHAL TO MUCOPURULENT MATERIAL, pneumonia in some cases, tonsil enlargement, retropharyngeal and trachealbronchial LN enlargement

CIRD

most common cause of mycotic and algar rhinitis/sinusitis in canines

aspergillus and penicillium spp

what breed is predisposed to aspergillus

GSD

gross lesion: NECROSIS of nasal epithelium , plaques of fibrinupurulent exudate, disruption of nasal conchae in chronic cases

mycotic and algae rhinitis/sinutisis in canines

histo: granulomatous inflamm mixed with fungal hyphae

mycotic and algae rhinitis/sinutisis in canines

cause of feline viral rhinotracheitis

feline herpesvirus 1

feline viral rhinotracheitis becomes ___ and shed during stress

latent in various ganglia

gross lesions of feline viral rhinotracheitis

tropism for epithelial cells results in necrosis and inflammation of the conjuctiva, nasal passages, pharynx, trachea

rhinitis and sinusitis with persistant SUPPURATIVE discharge in chronic cases

what are some lesions of feline calicivirus

mild oculonasal discharge, severe rhinitis, mucopurulenet conjunctivitis, ulcerative gingiviris glossitis and stomatitis

whats a common complication of feline calicivirus

secondary bacterial infection like bordetella, pasteurlla, e. coli

whats the most common mycotic infection in the feline nasal cavity

cryptococcosis

gross lesion: external swelling with nasal passage, discrete nasal granulomas to large confluent masses of mucosuppurative exudate filling entire nasal cavity and sometimes meningitis from extension into CNS

cryptococcosis in felines h

histo: yeast with abundant clear CAPSULE soap bubbles

cryptococcosis

common dz of pigs associated with atrophic rhinitis (pasteurella multocida, bord) with predisposing factors of genetics, environment, nutrional def

porcine progressive atrophic rhinitis

gross lesion: inflamm and atrophy of nasal conchae, DEVIATED SEPTUM, asymmetric conchae, in severe cases complete loss of conchae causing facial deformity

porcine progressive atrophic rhinitis

condition in YOUNG pigs from penetrating wound with swollen snout deformed snout

necrotic rhinitis in pigs

gross lesion: necrosis and suppuration of the nasal cavity and turbinates

necrotic rhinitis in pigs

what is Oestrus ovis in sheep

brown fly that deposits first stage larvae in nostrils of sheep. they mature into maggots and spend their time in nasal passages resulting in inflamm of airway

common dz of FEEDLOT cattle which gains entry thru lesions of viral infections or traumatic injury (from fusobacterium necrophorum aka oppurtunistic pathogen)

necrotic laryngitis

gross lesion: inflammation of mouth or larynx, well demarcated dry yellow gray thick crusted FIBRONECROTIC exudate can can progress ot ulceration

necrotic laryngitis aka calf diptheria

gross lesion: hyperemia and necrosis of nasal, pharyngeal, laryngeal, tracheal mucosa

secondary infection in necrotic regions = formation of thick layer of FIBRINONECROTIC MATERIAL and can turn into pneumonia

infectious bovine rhinotracheitis