Jenny Resp 2

Front 1

What is the mostcommon route by which injurious agents enter the respiratory tract?

Back 1

-Via inhalation (aerogenous route)

Front 2

What are the variousdefences of the upper respiratory tract?

Back 2

-The sneezing reflex
-The coughing reflex
-Warming and humidification of inspired air
-Mechanical filtration (nasal hairs trap large particles)
-Mucociliary clearance
-Chemical defenses
-Leukocytes (can be recruited from circulation)-Immune defenses (NALT and BALT)

-Normal microflora

Front 3

What are the clinicalsigns that are suggestive of disease of the nasal cavity or nasopharynx?

Back 3

-Nasal discharge (most common), sneezing,stertor (snoring or snorting sounds), reverse sneezing (dogs), gagging,open-mouthed breathing, rubbing at face or throat, decreased exercise tolerance+/- signs of systemic illness.
-Facialdeformity may become apparent with chronicity
-Clinical signs are often exacerbated by exercise, stress, hot weather, andexcitement.
-If there is a severe upper airway obstruction, affected animals may displaymucosal cyanosis or syncope (fainting)

Front 4

How do the normalflora play a role in the upper airway defense?

Back 4

They prevent the colonization of othervirulent organisms and modulate the immune response during infections. They canhowever become pathogenic if the mucosa becomes injured and they make their wayinto the submucosa. If there’s a disruption to this normal flora, there’s anopportunity for a bacterial or fungal infection.

Front 5

How does warming andhumidification of the air help with the upper respiratory system?

Back 5

-Helps to prevent desiccation (extreme dryness) of airway mucosa,promotes MCC clearance, and prevents exposure of the lower respiratory tract tocold air.

Front 6

What is BALT?

Back 6

-Bronchus Associated Lymphoid Tissue: located in the bronchial submucosaat branching points where inhaled particles impact on the mucosa

Front 7

What is NALT?

Back 7

-Nasal associated lymphoid tissue: forms post natally followingacquisition of commensal microflora in the nasopharynx. Small aggregates of Band T lymphocytes are also scatter throughout the nasal submucosa and lymphoidtissue encircles the oropharynx and nasopharynx.

Front 8

What are some of theimmune defenses in the upper respiratory tract?

Back 8

-Nasal associated lymphoid tissue (NALT)
-Bronchial AssociatedLymphoid Tissue (BALT)
-They are covered with a specialized epithelium that are involved with antigentransfer to the underlying lymphocytes. The lymphocytes traffic to otherlymphoid tissue to promote systemic immune response

Front 9

What are some of thegenetic conditions that are associated with the mucociliary clearance?

Back 9

-Primary ciliary dyskinesia (sick cilia syndrome or immotile syndrome);genetic disorder.
-Cystic fibrosis, malfunctioning protein doesn’t allow for the production ofthe serous layer for the cilia to beat, so they get bogged down by mucous.

Front 10

What are the chemicaldefenses of the upper respiratory tract?

Back 10

- Mucus in the upperairway contain multiple antimicrobial molecules
-Lactoferrin: binds iron rendering it useless to bacteria
-Lysozyme
-Beta defensins: peptides expressed either in health by tracheobronchialepithelial cells, or in response to pro-inflammatory cytokine. Capable ofkilling bacteria, fungi, and enveloped viruses by creating pores in theirmembranes
-Secretory IgA and polysaccharides that block mucosal attachment of bacteria

Front 11

What are the congenital malformations that involve the nasal cavity in the domestic animals?

Back 11

-Severe craniofacialdeformities
-Facial clefts
-Cystic nasal conchae
-Choanal atresia
-Brachycephalic airway syndrome

Front 12

What are the variouspossible components of brachycephalic airway syndrome?

Back 12

- Selective breeding for particular craniofacial features lead toconsiderable variation in the nasal cavity anatomy.
-Congenital abnormalities may include: stenotic external nares, elongated softpalate, everted laryngeal saccules, laryngeal collapse, trachealhypoplasia.

Front 13

What ischondrodysplasia?

Back 13

-An inherited condition in which impaired longitudinal growth of thecartilage model of the future skeletonàdisproportinate dwarfism. Affected animals will have abnormaldevelopment of the ethmoid bones and turbinates, and a short maxilla with anormal mandible.

Front 14

What isholoprosencephaly?

Back 14

-It is the term used for a spectrum of forebrain deformities whichtypically include agenesis or severe hypoplasia of the olfactory bulbs andtracts.
-The most severe expression is cyclopia

Front 15

What is cyclopia?

Back 15

-Associated with the absence of several cranial bones, a tube-likeproboscis located above the eye and not communicating with the pharynx, severemalformation of the forebrain, displacement or absence of the pituitary, andoften foetal gigantism due to prolonged gestation.

Front 16

What is a wry nose?

Back 16

-A congenitalmalformation where there is shortening and lateral deviation of the maxilla, premaxilla,nasal and vomer bones and nasal septum. Causes malocclusion of incisors andnasal obstruction

Front 17

What is cheiloschisis?

Back 17

-Cleft lip, uni or bilateral failure of fusion of the upper lips at themidline philtrum. May be superficial or it may extend into the nostril

Front 18

What ispalatoschisis?

Back 18

-Cleft palate. A midline defect in the hard and/or soft palate--> communication between the oral and nasalcavitiesà--> neonatal death fromstarvation and/or aspiration pneumonia.

Front 19

What is sytic nasalconchae?

Back 19

-Often occur in cattle. Uni or bilateral, smooth-surfaced, bony,projecting nodules in the ventral nasal meatuses. The cysts expand slowly overtime to cause progressive air flow obstruction with inspiratory and expiratorynoise.

Front 20

What is choanalatresia?

Back 20

-Uni or bilateral failure of formation ofa communicating channel between the nasal cavity and the nasopharynx. Usuallydue to persistence of the choanal membrane, but obstruction can involve bothsoft tissue and bone. Results in partial or complete obstructionof nasal airflow and exercise intolerance. Common in foal and crias.

Front 21

· Whichanimals are affected by brachycephalic airway syndrome?

Back 21

- Brachycephalic airway syndrome refers to the multiple congenitalanatomic abnormalities found in brachycephalic dog breeds and to a less extentshort faced cats

Front 22

What is theaieteogenesis of brachycephalic airway syndrome?

Back 22

- increased respiratory effort--> secondary inflammation and oedema of the laryngeal and pharyngeal mucosa--> enhanced eversion of the laryngeal saccules andfurther narrowing of the glottis--> exacerbation of the clinical signs.
-The prognosis depends on the severity of the abnormalities and their capacityto be corrected surgically. Laryngeal collapse is a poor prognostic indicator and may require permanent tracheostomy

Front 23

Reddening of thenasal mucosa may be due to either passive congestion or hyperaemia. What aresome circumstances in which nasal congestion or hyperaemia may develop?

Back 23

-Congestion of the nasal mucosa is a common post mortem finding, presumably reflecting terminal circulatory failure and pooling of venous blood in the submucosal vessels. Intense nasal mucosal congestion +/- haemorrhage is a feature of bloat in ruminants.
-Hyperaemia and odema of the nasal submucosa is expected in active inflammation.

Front 24

Outline theparasympathetic vs. sympathetic stimulation on the nasal cavity

Back 24

-Parasympathetic stimulation--> stimulation of nasal secretion and vasodilation and increasedpermeability of the submucosal blood vessels.
-Sympathetic stimulation--> Decreased nasal secretion,and vasoconstriction and decreased permeability of the submucosal blood vessels

Front 25

What is epistaxis?

Back 25

-Haemorrhage from thenose

Front 26

What are potentialcauses of epistaxis?

Back 26

-Trauma, foreign bodies, tumours, severe rhinitis, intense sneezingepisodes, and bleeding disorders. Infrequently, it may be caused by systemichypertension, right-sided congestive heart failure or an intra-nasal aneurysm.
-It can also arise from pulmonary haemorrhage or in horses, from a guttural pouch fungal infection

Front 27

What is a progressiveethmoid haematoma in a horse?

Back 27

-A unilateral space-occupying mass of organizing haemorrhage andreparative granulation tissue in the submucosa of the ethmoid turbinates.
-Associated with intermittent, usually unilateral epistaxis
-In extreme cases, the mass may fill the nasal meatus as far as the externalnares or extend into the maxillary sinus.

Front 28

What is rhinitis?

Back 28

· Inflammation of the nasal cavity

Front 29

What are potentialcauses of rhinitis in the domestic animals?

Back 29

-Viruses (canine distemper, feline calicivirus, herpesviruses
-Bacteria (Streptococcus equi, Bordetella bronchiseptica, Pasteurellamultocida)
-Fungi (Aspergillus, Cryptococcus neoformans)-Parasites (Nasal mites (dogs), fly larvae (sheep), leeches)
- Foreign bodies (sticks, splinters,dust, food particles)
-Allergens (plant pollens)

Front 30

What is acuterhinitis?

Back 30

- Characterised by nasal mucosal oedema and hyperaemia and exudationinto the nasal passages, with discharge from one or both nostrils.

Front 31

Serous rhinitis

Back 31

-Acute rhinitis usually commences with a serous nasal discharge thatcontains few leukocytes. Nasal muscosa is oedematous and hyperaemic and thereis increased secretion--> sneezing, snuffling.Nasal epithelium may be histologically normal or show evidence of hydropicdegeneration with cilia loss. Mildest form of rhinitis.

Front 32

Catarrhal Rhinitis

Back 32

-Within hours to days, the nasal exudate typically becomes morecatarrhal (mucoid) due to increased mucus production. Additional recruitment ofneutrophils and sloughing of mucosal epithelial cells.

Front 33

Purulent(suppurative) Rhinitis

Back 33

-Exudate thickens due to large numbers of neutrophils. Oftenaccompanying erosion and ulceration of the nasal mucosa. In severe cases, thenasal passage may be occluded by exudate. Typical of bacterial infection, but pus does not indicate bacterial infectionper se.

Front 34

What are some causesof fibrinous rhinitis in domestic animals?

Back 34

-Indicative of severe nasal mucosal injury with a marked increase invascular permeability--> leakage of fibrinogenand neutrophils.
-Coagulation of fibrinogen -->pseudomembraneformation.
-Caused by fungal rhinitis, infectious bovine rhinotracheitis, and in cattle Fusobacterium necrophorum infection.

Front 35

What are the grossand histological nasal lesions that can develop if rhinitis becomes chronic?

Back 35

-Progressive fibrosis of the nasal submucosa, atrophy of the submucosalseromucoid glands, and hyperplasia +/- squamous metaplasia of the mucosalepithelium.
-+/- formation of proliferative soft tissue masses
-+/- destruction and atrophy of nasal turbinate bones, deviation of the nasalseptum, and eventually gross craniofacial deformity.

Front 36

What islymphocytic-plasmacytic rhinitis?

Back 36

-Uni or bilateral chronic form of rhinitis in dogs, and to a lesserextent cats.
-Associated with persistent catarrhal to mucopurulent nasal discharge
-Histologically characterized by submucosal infiltrates of lymphocytes andplasma cells.
-May initially be triggered by viral, bacterial, or fungal infection, inhaledallergens, or foreign body trauma. Inflammation sometimes becomesself-sustaining via dysrefulation of local immune responses with ongoingcytokine release and recruitment of additional lymphocytes.

Front 37

What is granulomatousand pyogranulomatous rhinitis?

Back 37

-Characterised histologically by accumulation of submucosal macrophages and smaller number of lymphocytes, plasma cells +/- neutrophils or eosinophils.
-May cause formation of grossly protuberant mucosal nodules

Front 38

What are possiblecauses of chronic granulomatous to pyogranulomatous rhinitis in domesticanimals?

Back 38

-Chronic allergic rhinitis, chronic fungal infections, foreign bodies,chronic infections with Actinobacillus lignieresii or Actinomyces bovis inruminants.

Front 39

• What is allergic rhinitis?

Back 39

-May be associated with sneezing, nasaldischarge, lacrimation, nose rubbing, head shaking +/- epistaxis
-Type I (immediate) hypersensitivity to allergens--> exudation ofeosinophils and mucus
-Granulomatous (macrophage-rich) rhinitis typical in chronic phase

Front 40

Which domestic animalspecies are known to develop allergic rhinitis?

Back 40

- Recognised in dogs, cats, horses,cattle, and sheep.

Front 41

What are possibletriggers of allergic rhinitis?

Back 41

-A familialpredisposition is documented in cattle

Front 42

At what time of yearare animals most likely to be affected by allergic rhinitis?

Back 42

- affected in late spring to late autumn as a result of exposure toplant pollens

Front 43

Where can polypsdevelop as a consequence of chronic inflammation of the upper respiratory tract?

Back 43

-Polyps are masses of well-vascularised reparative connective tissue that can arise within the nasal cavity, nasopharynx or auditory tubes.
-Variably sized, smooth-surfaced, or ulcerated, tumor-like masses.
-Composed of a chronically inflamed, oedematous or fibrous core covered by hyperplastic respiratory epithelium or stratified squamous epithelium

Front 44

What are the clinicalsigns of a polyp?

Back 44

-Depend on the location
-Nasal polyp --> sneezing,nasal discharge, and even protrusion of the polyp through the nares,
-Nasopharyngeal polyp --> gagging, dysphagia, or dyspnea
-Aural polyp (one in the external ear canal)--> ataxia, unilateralhead tilt and Horner’s syndrome, and/or unilateral facial nerve paralysis.
-Polyps can be clinically silent and they can reoccur if they’re incompletelyexcised.

Front 45

Which species aremost likely to develop polyps of the upper airway?

Back 45

-In cats and horses

Front 46

To what anatomicsites can an infectious process involving the nasal cavity spread directly?

Back 46

-Into the paranasal sinuses (sinusitis), into the nasopharynx(nasopharyngitis) and/or along the auditory tubes, into the underlying nasalbones, or through the cribiform plate into the cranial vault to provokemeningitis and encephalitis.

Front 47

What is sinusitis?

Back 47

-Sinusitis=inflammationof the paranasal sinus

Front 48

What are possiblecauses of sinusitis in the domestic animals?

Back 48

-Commonly coexists with rhinitis and is an extension of it.

Front 49

In which domesticanimal species is sinusitis most often investigated and why?

Back 49

-In horses because oflimited drainage of the sinuses and the tendency for periodontitis to extend toinvolve the maxillary sinuses

Front 50

• Which sinuses are most often involved in sinusitis?

Back 50

-The frontal and maxillary sinus

Front 51

What is a sinusmucocoele?

Back 51

-In acute catarrhal and purulent sinusitis, the exudate often occludesthe sinus orifices--> impaired drainage--> chronic sinus mucocoele or sinus empyema.

Front 52

What are some causesof nasopharyngitis in the domestic animals?

Back 52

-Infections that involve the oral cavity, oropharynx, or nasal cavitymay extend to involve the nasopharynx.
-Ingested foreign bodies commonly lodge in the oropharynx of dogs
-Small foreign bodies may lodge in the caudal nadopharynx of dogs and cats
-In cattle large root crops may lodge in the pharynx
-Balling and drenching gun injuries in ruminants or rough intubation in anyspecies--> perforation of thecaudodorsal pharynx--> cellulitis.
-Pigs have a caudal pharyngeal diverticulum craniodorsal to the entrance of theoesophagus; plant awns and fibres may lodge there.

Front 53

What are the risksassociated with nasopharyngitis?

Back 53

- Airway obstruction and asphyxiation oraspiration pneumonia.

Front 54

Pharyngeal/laryngeallymphoid hyperplasia is common in young Thoroughbred horses. What are thoughtto be possible causes?

Back 54

-Chronic antigenic stimulation (from exposure to viruses or persistenceof bacteria), possibly compounded by vigorous exercise with drying of themucosa.

Front 55

What does Pharyngeal/laryngeallymphoid hyperplasia look like grossly?

Back 55

-May appear grossly as numerous tiny cream-white mucosal nodules or, in extreme cases, as large polypoid mucosal projections suggestive of neoplasia.
-In severe cases, the lymphoid hyperplasia may be accompanied by mucosal bacterial infection and inflammation

Front 56

What are the clinicalsigns that would be suggestive of guttural pouch infection in a horse?

Back 56

-Usually unilateral. In severe infection, erosion of the medial septumcan permit bilateral involvement.
-Clinical signs include nasal discharge, epistaxis, painful swelling of theparotid area, abnormally high head carriage, enlargement of regional lymphnodes, dysphagia, or other neurological signs, and stertor

Front 57

Which infectiousagents are most likely to cause guttural pouch infection in a horse?

Back 57

-Suppurative inflammation of a pouch is most often caused by infection with Streptococcus equi. (strangles), with guttural pouch involvement a sequel to abscessation of the retropharyngeal lymph nodes.
-Fungal infections are usually caused by Aspergillus fumigatus. Most often seen in stabled horses and probably initiated by inhalation of spores from mouldy hay. The inflammatory process is typically fibrinous.

Front 58

What are the possibleconsequences of guttural pouch infection, especially with fungal infection?

Back 58

-Guttural pouch empyema or especially mycosis may lead to compression orinflammation and necrosis of cranial nerves and/or the cervical sympathetictrunk and/or extend to involve the internal carotid artery (--> rupture and severe epistaxis, or septicthrombosis and/or cerebral septic thromboembolism)
-+/- facial or vestibular nerve injury
-+/- central blindness due to cerebral thromboembolism
-infection may also extend to involve adjacent hyoid bones, petrous temporalbone and middle ear on the atlanto-occipital joint.

Front 59

What happens if thereis damage to the glossopharyngeal nerve?

Back 59

-Damage to the glossopharyngeal nerve and the pharyngeal branch of the vagus nerve--> ipsilateral hypoaesthesia (decreased sensory perception) of the pharyngeal mucosa, pharyngeal paresis (weakness), dysphagia, and regurgitation

Front 60

What happens if thereis damage to the vagus nerve?

Back 60

-Damage to the vagus nerve--> laryngeal paralysis

Front 61

What happens if thereis damage to the cervical sympathetic nerve trunk?

Back 61

-Damage to the cervical sympathetic trunk or cranial cervical ganglion--> ipsilateral Horner’s syndrome

Front 62

What is gutturalpouch tympany?

Back 62

-Accumulation of air in the guttural pouch

Front 63

What is thought to bethe cause of guttural pouch tympany?

Back 63

-Thought to be due to abnormal valvular function at the nasopharyngealorifice of the auditory tube. Usually unilateral. Sever, non-painful andcompressible swelling of the parotid are on the affected side.
-Compression of the nasopharynx by the distended pouch-->stertor

Front 64

How old are horsesaffected by guttural pouch tympany?

Back 64

-Older than a year

Front 65

In which species arenasal tumours most often diagnosed?

Back 65

· -Mostcommonly seen in dogs and cats

Front 66

What are potentialrisk factors of a nasal tumor?

Back 66

Exposure to tobacco smoke, pollutants from coal fires and keroseneheaters.

Front 67

What are the clinicalsigns of a nasal tumor?

Back 67

-Sterterous breathing or sneezing, nasal discharge or epistaxis, facialdeformity, exophthalmos (protrusion of the eyes), tooth loss, or increasedlacrimation due to obstruction of the nasolacrimal ducts.
-Nasal tumors are commonly associated with secondary bacterial infections

Front 68

What are the commonnasal tumours in dogs and cats?

Back 68

-Nasal carcinomas are more common than sarcomas
-Squamous cell carcinoma
-Transitional cell carcinoma
-Adenocarcinoma
-Olfactory neuroblastoma
-Endemic ethmoidal carcinomas
- Tumors of the paranasal sinuses
-Tumors of the guttural pouch

Front 69

What is the expected behaviorof a nasal tumor in a cat or dog?

Back 69

-Most are malignant
-All nasal malignancies tend to be locally invasive and destructive but distantmetastasis is uncommon