Respiratory - Upper Respiratory Tract Flashcards
What are the signs of respiratory distress in SA?
- Respiratory rate >50 breaths per min
- Anxious, open mouth breathing
- Orthopneic position
- standing or sitting in a certian position to make breathing easier
- Reluctance to move
- Cough, wheezes, short shallow breaths
- Pale, cyanotic mucous membranes
Define stertor
snoring-like congestion of upper respiratory tract
Define stridor
Inspiratory wheeze over larynx
Devine wheezes
- Airway sounds occurring secondary to narrowing of bronchi, may be from increased secretions or inflammation
- most commonly expiratory, can be inspiratory or continuous
Define crackles
fine popping inspiratory sounds caused by opening of alveoli/small airways found in patients with pulmonary edema, pneumonia, or hemorrhage
What are the differentials for Epistaxis (nasal bleeding)
- Local:
- Aspergillosis
- Nasal Adenocarcinoma (other cancers)
- Trauma
- Foreign Body
- Dental Disease (abscess, fistula)
- Inflammatory (allergic)
- Nasal Mite (Pneumonysoides caninum)
- Systemic:
- Thrombocytopenia
- Systemic Coagulopathy
- Hypertension
- Multiple myeloma
How are systemic causes of Epistaxis diagnosed?
- Check platelets
- look for petechiae and do CBC or blood smear
- If low, think about tick-borne and immune-mediated disease
- May need to check clotting times (PT/PTT)
- Check blood pressure
- Hypertension can be related to:
- disease (Cardiac, Cushing’s, renal)
- drugs (phenylpropanolamine)
- Hypertension can be related to:
How are local causes of Epistaxis diagnosed?
- Check the teetha dn do an oral exam
- +/- CT Scan vs Skill Radiographs
- Before scope or biopsies
- +/- Rhinoscopy
- Biopsy nasal cavity
- Measure to medial canthus of eye
- Histopathology, culture
- Nasal flush with saline
What is Aspergillosis? common signalment? signs?
- Fungal organism commonly seen in dogs
-
Aspergillus fumigatus
- ubiquitous soil saprophyte
-
Aspergillus fumigatus
- Signalment:
- young - middle aged dogs
- Dolichocephalic breeds
- Outdoor dogs
- Rare in US cats
- Signs:
- Epistaxis, sneezing, pain
- May have depigmentation of nares
- Can invade cribriform and cause neurologic disease
How is Aspergillosis diagnosed?
- Imagining: Radiograph, CT, scope
- Cytology (fast)
- Histopathology (confirms)
- Antibody test - false negatives occur
- Antigen not helpful for nasal disease (helpful for systemic aspergillosis)
- Culture? - too slow
What is the treatment for aspergillosis?
- Debulk fungal plaques
- Clotrimazole infusion OR
- topical treatment under anesthesia for about 1 hour
- Complications - laryngeal irritation/inflammation
- Only if the cribriform plate is intact
- Itraconazole:
- systemic treatment 60-70% success rate
- 5 mg/kg PO BID for 2+ months
- Other options include ketoconazole and terbinafine
Why is fluconazole not a treatment option for Aspergillosis?
aspergillosis inherent resistance
What findings are common with Nasal Adenocarcinomas? how is it diagnosed?
- Common differential for older dogs with epistaxis
- PE: Pain, asymmetry, bony changes
- Diagnostics:
- Rads vs CT
- CT can be used for radiation planning too
- Nasal biopsies for histopathology
- CT/rhinoscopy help guide - can collect biopsies blindly
- Rads vs CT
What is the treatment for Nasal Adenocarcinoma?
- Radiation therapy is treatment of choice
- Consult with oncologist for other options
What is Lymphoplasmacytic Rhinitis?
- Allergies!
- Signalment:
- young/mid-age dogs, any cats
- German shepherds, dachshunds, (possible in any breed)
- Signs: chronic serous bilateral discharge
- Can have cough from post-nasal drip
- Sometimes has a cloudy or mucoid appearance
- Etiology: often unknown, likely multifactorial
What is the pathophysiology of Lymphoplasmacytic Rhinitis?
- Allergen present in nose
- Infiltration with inflammatory cells
- Vasodilation and ⇡ permeability
- Leakage of fluid into nasal cavity
- Destruction of mucociliary clearance
- Can have secondary bacterial infections
- Present with more mucoid/purulent discharge
What is the diagnostic plan for Lymphoplasmacytic Rhinitis?
- Consider likelihood of differentials
- Dental disease, foreign body, mites, fungal, bacterial, neoplasia
- Empirical treatment trial okay
- Confirm rhinitis with histopathology, rule out differentials
- Culture to identify secondary infection (if signs are present)
What is the treatment of Lymphoplasmacytic Rhinitis?
- Avoid allergens, smoke, etc (if IDed)
- Antihistamines - not routinely helpful
- Glucocorticoids
- Systemic: prednisone/prednisolone
- goal is control, not realistic to cure completely
- Inhaled fluticasone propionate
- rare systemic side effects
- Systemic: prednisone/prednisolone
- Cyclosporine
- alone or with steroid therapy
- Desensitization (?) small studies done
- Antimicrobial Agents (secondary bacterial infections)
What nasal mites are common in SA? Signs? Treatment?
- Pneumonysoides caninum
- Transmission - direct contact
- Signs:
- Sneeze, reverse sneeze
- serous or epistaxis
- Decrease smell
- Diagnostics: visualize mite
- Therapy: Selemectin, Ivermectin, Milbemycin
What is Feline Herpesvirus-1? Who is affected? How is it transmitted? Incubation time?
- Replicates in the upper respiratory tract
- Causes multifocal epithelial necrosis
- Osteolytic changes of turbinates
- Signalment:
- most severe in kittens
- multi-cat households or shelters
- Remain infected for life
- Transmission: Direct contact (fomites aerosol?)
- High morbidity, low mortality
- Incubation 2-6 day
What symptoms does Feline Herpesvirus-1 cause?
- Lethargy
- Fever
- Nasal and ocular discharge
- Sneezing, stertorous breathing
- Conjunctivitis, keratitis, corneal ulcers
- Rare oral ulcers
How is Feline Herpesvirus-1 treated?
- Self-limiting Disease
- Usually resolves in 1-3 weeks
- Carriers:
- nearly all recovered cats are latent carriers (trigeminal ganglia)
- Intermittent shedding and flare-ups
- Stress trigger
- 1 week lag to shedding that lasts 1-2 weeks
What is Feline Calicivirus?
- Single-stranded RNA virus
- High mutation rate
- Minimal repair
- Antigenic diversity
- Non-enveloped virus
- High morbidity, Low mortality
- Transmission:
- Shed in nasal, oral, and ocular secretions
- Fomites play an important role
What symptoms does Feline Calicivirus cause?
- Fever
- Sneezing
- Nasalocular discharge
- Oral ulceration - Hallmark!
- Conjunctivitis and chemosis
- Lameness
- Dermatitis
- Can also cause: vasculitis, edema (head/limbs) ulcers on skin and paws, multiorgan disease/failure
What is the treatment for Feline Calicivirus?
- Self-limiting disease
- supportive care
- Shedding temporary, not life-long
What are the core vaccinations for cats for respiratory diseases?
- Feline Rhinotracheitis (herpes-1)
- Feline calicivirus
- Panleukopenia
What are the goals of core feline respiratory vaccines?
- Minimize clinical signs and shedding
- will not prevent infection or carrier state
What are the differential Diagnoses for Upper Respiratory Disease in cats?
- Recurrent Herpesvirus or Calicivirus
- Secondary Bacterial infection
- Mycoplasma spp.
- Bordetella bronchiseptica
- Dental Disease or Fistula
- Nasopharyngeal Polyp of foreign body
- Neoplasia (lymphoma or carcinoma)
- Lymphoplasmacytic Rhinitis
- Fungal Disease: cryptococcus
What are the risk factors in cats for secondary bacterial infections?
- Chronic viral infection
- bony destruction
- brachycephalic
- repeated antimicrobial use
What are the normal respiratory flora that may cause secondary bacterial infections in cats? what are other options?
-
Staph, Strep, Pasteurella, Moraxella
- liquid doxy or amoxi (empirical choices)
- More resistant bacteria including Pseudomonas
What is the diagnostic Strategy for Cats with Upper Respiratory Disease?
- Mild/First occurrence:
- Discuss DDx, Vx status, exposure to other cats, stress
- If consistent with viral infection: diagnostic tests optional
- Educate owners about viruses
- Clinical signs likely to resolve without intervention
- Supportive care as needed
- Severe/Chronic
- Test for Cryptococcus
- Good dental exam, rule out polyp
- Imaging: nasal CT/rhinoscopy
- Biopsies for histopathology
- Culture for bacteria
- Test of Mycoplasma
What is the treatment for cats with Upper Respiratory Disease?
- Supportive:
- keep nose clean, nares patent
- Humidification
- Nutritional support
- L-lysine
- Antimicrobial trial?
- If mucopurulent discharge with fever, anorexia, lethargy
- Saline Nasal Flush
What is Bordetella bronchiseptica? What are the risk factors?
- Aerobic Gram-negative bacteria
- 1o and 2o pathogen
- Risk factors:
- Rescue cats
- Multi-cat households
- Exposure to dogs with kennel cough
- Concurrent respiratory infections
What are the signs of a Bordetella bronchiseptica infection in cats? diagnostics?
- Signs:
- Upper Respiratory Infection - sneezing, discharge
- Kennel cough - coughing
- Bronchopneumonia - dyspnea
- Diagnostics:
- Bacterial Culture or PCR - biopsies or wash
What is the treatment for Bordetella bronchispetica
- Oral liquid doxycycline 5mg/kg PO BID 2-4wks
Why are doxycycline pills not used in cats?
Can cause esophageal stricture!
What is Mycoplasma felis? (and other spp)
- Prokaryotic organism
- Lack cell wall (not true bacteria)
- Some are part of the normal flora of cats’/dogs’ upper respiratory tracts
- 1o or 2o pathogen
- Transmisssion:
- Direct contact and aerosol droplets
- Aspiration from own flora to lower respiratory tract
How are Mycoplasma spp infections diagnosed?
- Nasal biopsy, nasopharyngeal swabs, or airway wash
- Mycoplasma PCR
- Culture (request growth media for Mycoplasma)
What is the treatment for a Mycoplasma spp infection?
- Antibiotic that does NOT target the cell wall
- Doxycycline, azithromycin, fluoroquinolones
What is Cryptococcosis?
-
Cryptococcus neoformans
- More common in cat than aspergillosis
- Dimorphic fungus
- Nasal Cryptococcosis:
- Bump/mass on nose in common
- Very invasive
- Destroys turbinates
- External skin erosion/ulceratoin
- Can invade CNS via direct extension
- Through cribriform plate
What is the pathogenesis of Cryptococcosis?
- Spores inhaled
- Classically “pigeon droppings”
- Most stay locally in the nose
- may spread to skin, eyes, CNS
What is the common signalment of cats with Cryptococcosis?
- Any breed (Siamese, Birmans, Ragdolls ⇡ risk)
- Usually young adults
- ⇡ risk:
- outdoor cats
- live near construction sites
- Immunosuppressed (FIV+, FeLV+, steroids)
What are the signs and symptoms of Cryptococcosis?
- History:
- ⇣ appetite, weight loss, nasal and ocular discharge, sneezing
- PE:
- BAR, usually not febrile
- Bump on nose, ulceration, palpable bony destruction, asymmetry, pain
- Decreased nasal airflow, discharge
- May have big lymph nodes, neurologic deficits, blindness
- Fundic exam ⇢ chorioretinitis
What are the diagnostic tests for Cryptococcosis?
- Cytology of mass, ulcer, discharge
- Aspirates, are fast, easy, and may be diagnostic
- India Ink, Diff-Quik, New methylene blue
- Numerus small yeast with thick/large capsule
- Latex agglutination for Capsular Antigen
- 90-100% sensitivity and specificity on serum
- Biopsy - wedge or punch biopsy on superficial lesion
- Nasal CT Scan, biopsies inside the nose, CSF for latex agglutination are options
What is the treatment of Cryptococcosis?
- Fluconazole
- 10 mg/kg PO BID
- treat for 1 mo past resolution of signs
- Side effects: GI upset and hepatotoxicity
