Disorders of the Equine Lower Resp Tract 2 Flashcards
what are the differentials for coughing (13)
- severe equine asthma and SPA-SEA
- mild to moderate equine asthma
- URT inflammation/irritation/trauma
- influenza, equine herpes virus etc
- S. equi equi infection (Strangles)
- dysphagia
- bacterial or viral pneumonia
- parasitic pneumonia
- URT/LRT foreign body
- neoplasia
- pulmonary edema
- neoplasia
- smoke inhalation
when should you assume infectious respiratory disease
- pyrexia
- is the horse unwell?
- enlarged lymph nodes
- other animals effected
what is the difference between tracheal and bronchoalveolar lavage
what age of horse does mild to moderate equine asthma affect
young athletic horses but it can be any age
what are the clinical signs of horses with mild to moderate equine asthma (4)
- exercise intolerance/poor performance
- coughing
- increased resp secretions
- no increased expiratory effort (dyspnea) at rest –> but perhaps at exercise
what is the etiology of mild to moderate equine asthma (4)
- environmental dusts/organic particals/gases etc
- bacteria/virus
- genetics, immune status
- exercise induced pulmonary hemorrhage (EPIH)
how is mild to moderate equine asthma (5)
- history and clinical exam
- endoscopy
- cytology particularly of BAL
- pulmonary dysfunction
- pulmonary hypersensitiviy
how is mild to moderate equine asthma diagnosed on endoscopy
+/- tracheal mucus (often excessive)
TW with culture to rule out bacterial infection
what is seen on BAL cytology with mild to moderate equine asthma
neutrophilia
some may have increased inflammation 5-20% of differential count
how is mild to moderate equine asthma treated
similar to SEA
- low dust environment
- corticosteroids
what are the types of corticosteroids used to treat mild to moderate equine asthma
systemic
inhaled
how is the mild to moderate equine asthma response of treatment monitored
subclinical so need to repeat BAL cytology to confirm
how is mild to moderate equine asthma prevented in young horses
- low dust environment (feeding/housing/bedding) –>avoid peak concentrations, mucking out etc.
- good ventilation
what is the difference in signalment with mild/moderate vs severe equine asthma
MEA usually young adults
SEA > 7 years
what are the difference in clinical signs in mild/moderate vs severe equine asthma
MEA: no dyspnea at rest, may have tachypnea
what are the differences in BAL cytology in mild/moderate vs severe equine asthma
what is the difference in prognosis of mild/moderate vs severe equine asthma
MEA: short duration, can resolve spontaneously or with treatment, low risk of recurrence
SEA: long duration, recurrent
what is exercise induced pulmonary hemorrhage
common pulmonary disorder of the hrose
associated with strenous exercise
what is the pathogenesis of EIPH
unknown
stress failure of pulmonary capillaries
may be associated with mild/moderate equine asthma
low alveolar pressure?
upper airway obstruction?
mechanical forces associated with poor performance?
does EIPH cause poor performance
moderate to severe EIPH associated with reduced performance
BUT many horses have EPIH without impaired performance
what are the presenting signs of EIPH (5)
- none
- +/- post exercise/race epistaxis
- +/- poor performance
- +/- repeated swallowing post exercise/race
- +/- prlonged recovery post exercise/race
what are the clinical signs of EIPH
- none
- +/- epistaxis
- +/- abnormal lung sounds (rarely)
how is EIPH diagnosed
- endoscopy (30-60 min post exercise)
- BAL cytology: free red blood cells, hemosiderophages, +/- neutrophils
how is EIPH treated
aim to reduce hemorrhage, minimize sequelae (inflammation/fibrosis)
how can frequency of EIPH episodes
altered training
prophylaxis –> frusemide
what is interstitial lung disease
acute or chronic inflammatory process of primary alveolar walls and adjoining bronchiolar interstitium
what does acute phase interstitial lung disease
present in acute respiratory distress
how does chronic phase interstitial lung disease present
presents clinically like SEA
what are the causes of interstitial lung disease (3)
multifactorial
- toxic agents: mineral oil, silicosis
- infectious agents: bacteria, virus, parasite
- idiopathic
how is interstitial lung disease diagnosed
process of elimination and radiography
how is interstitial lung disease treated
treat infectious agent (if present) and anti-inflammatory therapy
what is equine multinodular pulmonary fibrosis (EMPF)
a progressive fibrosing lung disease associated with presence EHV-5
when is equine multinodular pulmonary fibrosis seen
typically in older horses
often intially suspected to be SEA or infectious bronchopneumonia
what are the signs of equine multinodular pulmonary fibrosis (EMPF) (4)
- tachypnea
- tachycardia
- weight loss
- pyrexia
what can be heard on auscultation with equine multinodular pulmonary fibrosis (EMPF)
wheezes and crackles
how is multinodular pulmonary fibrosis differentiated from SEA
prove it is NOT reversible –> administer short acting bronchodilator? buscopan
how is multinodular pulmonary fibrosis differentiated from infectious pneumonia
BAL cytology –> non septic neutrophilia
what is seen on BAL samples with multinodular pulmonary fibrosis
presence of EHV-5
what is seen on radiography with multinodular pulmonary fibrosis
diffuse, nodular interstitial pattern
what is seen on ultrasonography with multinodular pulmonary fibrosis
diffuse pleaural thickening
may identify nodules superficial in lung
biopsy
how is multinodular pulmonary fibrosis treated
fair to poor prognosis
dexamethasone, doxycyline, acyclovir
what causes lungworm
Dictylocaulus arnfieldi
what is a question you should ask when examining a horse to distinguish SEA from lungworm
has there been any contact with donkeys/mules
what is seen with horses on lungworm
- BAL cytology
- larvae in tracheal wash
- few eggs in feces as usually not patent infection in horses