Cough/ Nasal discharge Flashcards
What is the physiology of cough?
Cough reflex removes secretions from the tracheobronchial tree promise to the level of the segmental bronchi
Mucociliary escalator => Continuous waves of ciliary motion that start at the level of the bronchioles
What is the neural pathway initiating cough?
Involuntary reflex - involve sensory receptor through tracheobronchial tree —> predominantly vagal nerve
Voluntary
T/F: irritants can trigger both bronchoconstriction and cough and bronchoconstriction is a constant component of cough
True
Both work through separate reflexes though
What can stimulate a cough?
Bronchoconstriction
Excessive mucous production
Deposition of inhaled particles
Release of inflammatory mediator (infectious disease)
Exposure to hot or cold air
Intramural or extramural pressure (tumor, fibrosis, pleural effusion)
Sloughing of airway epithelium (eg smoke inhalation)
Enhanced epithelial permeability
The mucociliary mechanism is made up of a pseudostratified columnar epithelium, how long does this take to regenerate when damaged? How does this relate to resolution of clinical signs?
7weeks
If clinical signs do not resolve right away it could be because of the time it takes to regenerate
ESP with viral conditions —> kills epithelium
What cells secrete surfactant like substances that aids in maintaining patency of airway?
Clara cells
Metabolize airbone toxins
What do premature foals lack that can cause them to suffer from pleuropneumonia ?
Clara cells
Lack of surfactant keeps the airway open
Decreased mucociliary clearance can be caused by?
Decreased cell number Mucous plug Dehydration Irritant gases Dust Cold weather Anesthetic
What will you do as part of your PE on a coughing animal?
Auscultation HR
Increase HR, RR, RE and fever
Nasal discharge
- mucopurulent
- anaerobic bacteria: associated with foul smell
Palpate the thoracic wall
- pleura friction rubs
- fractured ribs
Rebreathing exam
- inhalation of expired CO2
- Eupnea and hyperpnea
When listening to lung sounds, increased lung sounds with crackles and wheezes indicate?
Pneumonia
On auscultation of the lungs, a ventral dull sounds may indicate??
Pleuropneumonia
What is the DDX for cough with fever?
Infectious
Secondary to non-infectious condition
What is the DDX for coughing with no fever?
RAO Larynx or pharyngeal abnormality Parasitic EIPH Foreign body Neoplasia Trauma
What is the peracute clinical manifestation of pleuropneumonia?
Fever Depression Anorexia Pleuodynia : smiler signs to colic (abducted elbow, laminitic, weight losss) Cough may not be present Lung sounds may be normla
Hyperpnea Weight loss (catabolic, decreased appetite)
What are the viral respiratory diseases that can cause a pneumonia?
Equine influenza Equine herpes 1 and 4 Equine viralarteritits Equine adenovirus Equine rhinovirus Hendra virus
A young horse with high fever, cough, and lameness. You ruled out laminitis with hoof testers..
What is your DDX
Both
Equine influenza and equine herpes virus cause respiratory problems and a polysynovitis
EHV can also have conjunctivitis, lymphadenopathy, edema, and vasculitis
What systems do EHV1 and EHV4 affect?
EHV1: respiratory and neurologic
EHV4: respiratory and reproductive
What virus causes respiratory disease, abortions and foal pneumonia but most infections are Subclinical
Equine viral arteritis
Who is most likely to be infected with equine adenovirus
Immunopcompromised foals (SCID)
It is late winter-early spring, and a young horse presents with nasal discharge, laryngitis, and mild bronchitis..
What would be you top ddx?
Equine rhinovirus
What viral disease causes febrile illness, facial swelling, head pressing, and recumbency and can also be zoonotic
Hendra virus
What are the aerobic bacteria that can cause a pneumonia?
Strep zooepidemicus Staph aureus Actinobacillus equuli Pasturella E. Coli Klebsiella pneumoniae Pseudomonas Rhodococcus equi
What are the anaerobic bacteria that can cause pneumonia ?
Bacteroides fragilis
-common in horses with physiologic stress, including transportation, exercise, and viral infection
Parasitic infection of horses lungs?
Dictylocaulus arnfildi (lung worm )
Parascaric equorum (roundworm) — migrate through lung during PPP
In what environment are you more likely to see a primary fungal pneumonia?
Dry and dusty
Stress is a major contributor for bacterial pneumonia/pleuropneumonia.. what are some stressors in a horse?
Transportation — head elevated can compromise mucociliary clearance/ dehydration can decrease secretions
Exercise —increase in peripheral neutrophil function and oxidative burst of alveolar macrophages
Anesthesia — cuff pressure to high (tracheal necrosis, dorsal recumbency cause atelectasis , anesthetics cause depression of resp defense mechanisms
What can be the EDX of aspiration in a horse?
Stomach tube - with mineral oil
Choke
Laryngeal hemiplegia
Dysphagia — neonatal encephalopathy — botulism — guttural pouch disease — strangles
Severe bronchoconstriction
Pseudomonas cast
Carboxyhmeoglobin >10%
What is the EDX?
Smoke inhalation
What is the most common primary lung tumor in horse?
Glandular cell
DDX:
Pulmonary chondrosarcoma
What virus is associated equine multinodular pulmonary fibrosis
EHV5
How does equine multinodular pulmonary fibroisis?
Exercise intolerance
Acute respiratory distress
What type of pattern is present on rads that would be consistent with equine multinodular pulmonary fibroisis?
Diffuse bronchointerstitial pattern with multiple coalescing circular nodules throughout the lung field
Horse presents ..
Thin, dull attitude, poor hair coat Tachypnea Increased RE and RR Abnormal lung sounds Occasional dry cough Increased WBC Increased firbrinogen
What is your ddx?
Infectious pneumonia
Viral
Bacterial
Fungal
Parasitic
Horse presents ..
Thin, dull attitude, poor hair coat Tachypnea Increased RE and RR Abnormal lung sounds Occasional dry cough Increased WBC Increased firbrinogen
What diagnostic tests can you do?
Rads
US
Horse presents ..
Thin, dull attitude, poor hair coat Tachypnea Increased RE and RR Abnormal lung sounds Occasional dry cough Increased WBC Increased firbrinogen
Rads- diffused bronchointerstitial pattern with multiple coalescing circular nodules
US- multiple circular hypoechoic masses
DX?
Equine multinodular pulmonary fibroisis
Proposed treatments of EMPF?
Corticosteroids
NSAIDS
Antiviarals — meh, questionable if it works (depends on budget)
Bronchodilators - meh
Oxygen supplementation usually not beneficial because gas exchange cannot occur
Antifibrotic agents
Immune modulators
What can be the cause of foal pneumonia in an animal less than 1month and what are the infectious organisms involved?
In utero or perinatal infection
Aspiration - meconium, reflex, from nasogastric tube
Surfactant inactivation
Adenovirus (SCIDS)
EVA, EHV1, EHV4
—> can lead to secondary bacterial infection
What can be the cause of foal pneumonia in an animal that is 1-6months and what are the infectious organisms involved?
Strep equi zooepidemicus Rhodococcus equi (chronic —> abscess formation)
Respiratory viruses are often the primary agents (EVA, EHV)
T/F: hyperfribinogenemia and neutropenia reflect an acute process
True
What does a neutrophilia anemia indicate in a case of pneumonia? What is it is a left shift neutropenia??
Chronic
Left shift= very bad prognosis
Horse presents with
Symmetric airflow from lungs
Expiratory
Abnormal lung sounds
There is cough but and mucopurulent discharge (bilateral)
Temp is normal
Abnormal lung sounds
What would be your DDX?
What would be your next step diagnostically?
Non- infectious lower airway disease
No fever— infectious causes are unlikely
DDX: Equine asthma (inflammatory airway obstruction or Recurrent airway obstruction)
Smoke inhalation
Neoplasia (granular cell tumor or pulmonary chondrosarcoma)
Equine multinodular pulmonary fibrosis (associated with EHV5)
Diagnostics:
Endoscopy—> should see pseudomembranous cast with smoke inhalation
BAL
Rads and US for neoplasia or EMPF
Adult horse presents with..
Intermittent cough
Serous/mucous bilateral nasal discharge
Symmetrical nasal flow
Abnormal lung sounds : crackles and wheezes
Temp: high
What is your DDX
What further diagnostics will you do?
Infectious lower airway disease
DDX: Pneumonia/ pleuropneumonia —> Bacterial —> fungal —> parasitic —> viral (equine viral arteritis, most other resp viruses affect young horses)
CBC— infectious would have neutrophilia and hyperfibrinogenemia (left shift => bad prognosis)
Transtracheal wash — culture
Young horse in a breeding facility..
Has bilateral serous/mucoid discharge
Symmetrical nasal air flow
Cough
Abnormal lung sounds
What is your top DDX and what further diagnostics would you do ?
Infectious lower respiratory tract disease
Foal pneumonia
— rhodococcus
—streptococcus equi zooepidemicus
CBC - neutrophilia and hyperfibrinogenemia ( much higher in cases of rhodococcus )
Ultrasounds — pleural abnormalities
Rads — lung consolidation
TTW — culture and cytology (neutorphils)
Following a race…
An older horse presents with bilateral epistaxis
What would be your differentials??
What would you do next diagnostically?
Exercise induced pulmonary hemorrhage
Trauma
Ethmoid hematoma
Guttural pouch myositis
Pulmonary abscess rupture
Coagulopathy
Endoscopy
EIPH —> +/- blood in trachea
Ethmoid hematoma —> mass in nasal cavity
Guttural pouch myosis —> visualize plaque in pouch
Trauma ( usually by history)
Horse presents with
Symmetric airflow from lungs
Expiratory
Abnormal lung sounds
There is cough but and mucopurulent discharge (bilateral)
Temp is normal
Abnormal lung sounds
Endoscopy shows some tracheobronchial mucus BAL shows.. neutrophils >10% masts > 5% Eos >5%
What is your dx?
Inflammatory airway disease
=> clinical signs are not severe enough and neutrophils not high enough for recurrent obstructive airway disease (25%)
Horse presents with
Symmetric airflow from lungs
Expiratory
Abnormal lung sounds
There is regular and frequent cough but and mucopurulent discharge (bilateral)
Temp is normal
Abnormal lung sounds and increase respiratory effort
Inappetence and weight loss
Endoscopy shows some tracheobronchial mucus
BAL shows..
neutrophils >25%
What is your dx?
Recurrent airway obstruction
What is the treatment for inflammatory airway disease?
Environmental
Decrease airborne dust, bedding, and feed
Anti-inflammatories
What is the treatment for recurrent airway obstruction??
Environmental
Reduced dust, bedding
Increase ventilation
Anti-inflammatories
- > corticosteroid (prednisolone or dexamethasone)
- > triamcinolone acetonide and isoflupredone
- > fluticasone propionate
- > dedomethasone
Bronchodilators
-> anticholinergic (atropine - careful can cause ileus)
- > phosphodiesterase inhibitors
- > B2-agonists (clenbuterol - increase intracellular cAMP and cause smooth muscle relaxation, also some anti-inflammatory properties)
What are the aerobic bacteria that ca cause a pneumonia?
Strep zooepidemicus Staph aureus Actinobacillus equi E.coli Klebsiella Pseudomonas Rhodococcus equi
What anaerobic bacteria cause a pneumonia?
Bactericides fragillis
What are the lung worms that can cause a pneumonia?
Dictylocaulus arnfeldi
Parascaris equorum
What are the theories for cause of EIPH?
Capillary rupture theory - stress failure of vessel wall where pulmonary capillary vessels increase and rupture
Lower airway inflammatory theory
Previous dz has damaged airway causing weak areas of fibrosis
Concussive lung injury theory
Impact of hoof on ground transmitted to lung causing shearing in caudodorsal lung
How would you grade this EIPH?
Flecks of blood or a short narrow line
Grade 1
How would you grade this EIPH??????????
Multiple distinct streams covering >1/3 of trachea?
Grade 3
How would you grade this EIPH?
Multiple coalescing streams covering >90% of trachea
Grade 4
What is the treatment for EIPH?
Furosemide
Controversial because it causes loss of weight and better racing times
Nasal strip (flair)
Young horse presents for
Unilateral serous nasal discharge
Temp high
No abnormal lung sounds
What are your top DDX
What diagnostics would you do next?
Infectious upper respiratory disease
Viral
Infectious sinusitis
Culture and sensitivity
PCR
What are the possible clinical presentations of strangles?
Pneumonia Pleuropneumonia Guttural pouch empyema Weight loss Colic of other causes
You have a horse that presents with
High fever and depression
Purulent-yellow-green discharge
Respiratory distress
Swelling of the submandibular and retropharygenal lymph nodes
Top DDX?
Strangles
Infectious cause = streptococcus equi var equi causes the high fever
Swelling of the retropharyngeal lymph nodes can lead to respiratory distress
What is the aseptic vasculitis associated with strangles in mature horses called?
Purpura hemorrhagica
What respiratory diseases are associated with purpura hemorrhagica ??
How do you treat this?
Influenza
Strangles
Purpura hemorrhagica is treated with corticosteroids
What is bastard strangles???
Systemic manifestation of strangles
Mets to lymphnodes throughout body —> lungs, mesentery, liver, spleen, kidney, and brain
Ocular
Endocarditis
Suppurative necrotic bronchopneumonia
What is the treatment for bastard strangles?
No complications — best to let dz run its course
Accelerate maturation of abscesses and provide drainage
Long term antimicrobial therapy (complicated disease)
Biosecurity
- isolate
- monitor for feverr
- quarantine until no postive results
Vaccination
What specific tests can you do to diagnose bastard strangles?
Anti-strep antibody titer
SeM specific ELISA
Serum amyloid A (can help distinguish which animals to give antibiotics — if high)
What immune-mediated complications can arise from strangles?
Purpura hemorrhagica
Myositis
Glomerulonephritis
Myocarditis
What are the EDX for foal pneumonia?
Strep zooepidemicus
Actinobacillus equi
How do you treat foal pneumonia?
Depends on degree of pneumonia
- gram pos
- gram neg
Bronchodilators
Fluid therapy
Anti inflammatory
Nebulization
