Respiratory Pathology up to Sp Pneumonias (AH) Flashcards
What makes up the Conductive respiratory system?
nostrils, pharynx, larynx, trachea, and bronchi
What makes up the Transitional respiratory system?
bronchioles
What makes up the gas exchange system?
Pneumocytes in alveoli
What are the two types of pneumocytes and which one can regenerate?
Type I-membranous (BM)- no regeneration –> fluid into alveoli from blood vessel. Type II- granular. Type II regenerates.
What makes up the detox system?
Goblet cells in the bronchioles are replaced by clara cells (detox similar to hepatocytes)
***What are the main routes of entry of etiological agents?
Aerogenous (infectious/non-infectious). Hematogenous (infectious/toxins). Direct extension (infections through trauma)
What are the main defense mech against aerogenous entry?
- Sneeze, cough, reflex bronchoconstriction. 2. Mucocilliary effect: mycociliary clearance, antibodies, lysosomes, mucus. 3. BALT: bronchiole associated lymphatic tissue (immunologic). 4. Alveolar macrophages
What does mucocilliary defend against?
***Particles >10um, about 5% of particles 1-2um in Bronchi
**Which bacteria are resistance to alveolar macrophages?
Mycobacterium, Rhodococcus, Lysteria spp.
**Which spp. defend against blood borne agents with pulmonary intravascular macrophages?
Ruminants, pigs, cats and horses
**In what spp. are hepatic and splenic macrophages key in fighting blood borne agents?
Dog, rodent, human
How do viruses impair pulmonary defense mechanisms?
Destruction of mucocilliary blanket and Impaired alveolar macrophage function
How do bacteria impair pulmonary defense mech?
Some live and replicate within macrophages. Produce toxins –> direct destruction of cells
Rhinitis
Inflammation of the nasal cavity
Main causes of rhinitis?
virus, bact, fungi, chemicals and allergens, parasitic.
How is rhinitis characterized?
by the nature of the exudate which varies by causative agent
What are the types of exudate associated with Rhinitis?
Serous - serum. Catarrhal - Mucous membranes. Purulent - pus. Hemorrhagic - blood. Granulomatous - granulation/ ulcers
What is the only dz of the nasal cavity and sinuses is found in bovine?
Infectious bovine rhinotracheitis (red nose)
What is the etiology of IBR?
Bovine herpes virus
What type of discharge is associated with IBR?
Serous to mucopurulent
When is IBR fatal?
2* M. hemolytica infection –> pneumonia
What are the CS of IBR? (5)
Pyrexia, anorexia, coughing. Serous to mucopurulent nasal discharge. Lacrimation and corneal opacity. Inflammed nares (red nose). Dyspnea of laryngitis develops.
What is a micro lesion of IBR?
INIC bodies
In addition to nasal infections what else can IBR cause?
Genital infections in breeding cattle
Nasal Granulomas are found in which animals?
almost all animals
Etiology of nasal granulomas?
*Mycotic is the main cause: R. seeberi in cattle, dog horse, cat. C. neoformans in cat. Aspergillus and penicillium in dogs. Blood fluke - Schistosoma nasalis in cattle. Allergic - all spp.
Gross lesions of nasal granulomas?
granuloma is seen as polypoid nodules Cauliflower like). Soft, pink and bleed easily. Large growths may obstruct the nasal passage –> resp. distress.
What are diseases of the nasal cavity in sheep and goats? (3)
Non-specific Dz. Nasal granuloma, Myasis (O. ovis larvae), Endemic Ethemoidal Carcinoma
What diseases of the nasal cavity do horses get? (6)
Eq. viral Rhino, Eq. Influenxa, Eq. Viral Arteritis, Strangles**, (Glanders, Meliodiosis)
Etiology of equine viral rhinopheumonitis (EVR)?
Herpes 4 (occasionally Herpes 1)
Type of exudate associated with EVR?
Serous inflammation
CS of EVR?
serous inflammation of nasal mucosa, sometimes edematous swelling of pharyngeal lymph nodes, conjunctivitis, cough, , fever, coughing, congestion.
Lesions of EVR?
**Ulceration and necrosis of resp. epithelium with INIC in epithelial cells.
Ddx of EVR?
equine influenza and equine viral arteritis. (VI, serology)
Equine influenza etiology?
Type A Orthomyxovirus
Type of discharge associated with Eq. flu?
Serous discharge first, then mucopurulent later.
Lesions of Eq. flu?
*Usually not seen in the nasal passages. Mild Dz but may lead to *interstitial pneumonia and pulmonary edema.
Dx of Eq. flu?
Need lab confirmation to differentiate for other resp. viruses. VI/serology
Etiology of Eq. Viral Arteritis?
Arterivirus
Lesions of Eq. viral arteritis?
*serous (to mucopurulent) rhinitis. Conjuctivitis and plapebral edema. Fibrinoid degeneration of muscular arteries. –> hemorrhage in varius tissues
CS of Eq. Viral arteritis?
edema of the limbs and ventral abdomen. Respiratory distress, feer, diarrhea, colic, abortion in 50-80% of mares.
Etiology of Strangles?
Strep. equi equi*
CS of strangles?
bilateral mucopurulent nasal discharge. Lymphadenopathy and painful swalling of lymph glands. Fever.
Lesions of Strangles?
*suppurative rhinitis and lyphadenitis
***Sequelae of strangles?
Purpura hemorrhagica (type III hypersens.) Extension of infection to: paranasal sinuses, Guttural poush, internal organs. Facial paralysis and horners syndrome. Laryngeal hemiplagia.
Dx of strangles?
isolation of bact from surgically drained abscess of lymph gland
What is a nasal polyp?
growth on nasal or septum mucosa made of chronic inflammatory leasions. Cause is unknown. Surgery is curative.
What are the diseases of nasal cavity in dogs?
Transitory rhinitis, Nasal granuloma, Linguatula serrata, Allergic rhinitis.
What is transitory rhinitis is a generlized dz associated with?
*Generalized bacterial and viral Dz. (Bact. - B. bronchiseptica, E.coli, P. multocida. *Viral - canine distemper, canine adenovirus 1,2, reovirus, canine herpes virus, and areainfluenza virus)
Nasal granuloma is associated with what type of infection?
Fungal
What is Lingualtula serrata ? What kind of inflammation does it produce and in which type of animals?
Specialized arthropod. Produce catarrhal inflammation in carnivores.
*What are the diseases of the nasal cavity in cats?
Feline virus rhinotracheitis (FVR), Feline Calicivirus, Feline Chlamydiosis, Feline Respiratory Disease complex
Etiology of FVR?
Feline herpesvirus 1
Besides respiratory infection, what else can FVR cause?
Ulcerative keratitis, hepatic necrosis, abortion and stillbirths
Where is FVR found?
Worldwide
CS of FVR?
Suppurative rhinitis, conjunctivitis with oculonasal discharge
What other resp. disease is similar to FVR in cats?
Feline calicivirus
Which two viruses account for 80% of resp. disease in cats?
FVR and FCV
CS of FCV? What is unique?
Conjunctivitis, rhinitis. Unique: herpes virus in immunocompromised cats –> ulcers of the tongue and hard palate.
FCV Dx?
differentiate from FVR by** ulcers on tongue and hard palate. **
What is limping kitten syndrome?
An acute self limiting arthritis caused by infection of vaccination with some FCV strains.
What does Feline Chlamydiosis cause?
Conjunctivitis and serous to mucopurulent rhinitis