Respiratory Disease Flashcards
1
Q
Eupnea
A
- Normal breathing
2
Q
Hyperpnea
A
- Breathing fast but deep
- Hypoxemia or pain
- NOT like they are struggling to breathe
3
Q
Dyspnea
A
- Difficulty breathing
- Nostril flare
- Abdominal effort
4
Q
Normal lung fields in a horse
A
- Quite small
- Draw a dorsoventral line behind the shoulder
- Draw a line cranially from the tuber coxae
- Draw a line connecting them from the level of the elbow
5
Q
Rebreathing exam goal
A
- Get them to take a deep breath
- Easier to hear abnormal sounds
- See how they can tolerate the bag
- How long does it take to recover?
6
Q
What lymph nodes should you be able to feel normally in the facial region? Which lymph nodes do we get very worried about if we can feel them?
A
- Submandibular you should be able to feel
- Retropharyngeal if palpable that is quite worrisome (Strangles)
7
Q
What sample is best to take if you want to culture?
A
- Transtracheal wash
- Lower respiratory tract
8
Q
Normal cytology for TTW
A
- Greater amount of macrophages normal
- Should be <20% neutrophils
- Sampling lower respiratory tract
9
Q
When to use bronchoalveolar lavage?
A
- Inflammatory conditions or hemorrhage
- Not sterile
10
Q
Where can you take arterial samples from in the adult horse?
A
- Transverse facial artery only
11
Q
Where can you take arterial blood gas from in the foal?
A
- lateral metatarsal artery
- Transverse facial artery
12
Q
Four structures that are caudal to the mandible?
A
- Guttural pouch
- Retropharyngeal lymph node
- Thyroid
- Salivary gland
13
Q
Dfdx for a distended guttural pouch
A
- empyema
- Tympany
- Hemorrhage
14
Q
Important structures in medial guttural pouch (larger pouch)
A
- IX-XII
- Sympathetic trunk
- Internal carotid
15
Q
Diagnostics for a non-painful distention of GP
- Worse on the right side
- Acute
- Afebrile
- Only affected
A
- Endoscopy (visualization, lavage, culture)
- Sedation
- Radiographs may help
16
Q
Who gets GP tympany?
A
- Arabians, fillies
17
Q
Treatment for GP tympany?
A
- Decompress
- Good prognosis
- can go in and cut a hole
18
Q
Primary signs indicating dysphagia?
A
- Nasal discharge of feed material
- NOT DROPPING OF FEED/QUIDDING
19
Q
GP empyema etiology
A
- Streptococcus equi sbsp zooepidemicus or equi
20
Q
Diagnosis for GP empyema
A
- endoscopy and culture or PCR
21
Q
Treatment for GP empyema
A
- Lavage and removal
- Topical antibiotics (Penicillin best)
- NSAIDs
22
Q
What should you think about with an acute onset respiratory noise and distress with retropharyngeal lymph node enlargement?
- Bilateral, no fever
A
- Think of strangles
- Streptococcus equi sbsp equi
23
Q
If a horse has fever and you suspect Strangles, is it shedding or not?
A
- Not shedding
- Fever occurs 1-2 days before shedding
- You could prophylactically give Penicillin during an outbreak to prevent abscessation
24
Q
Carriers of Strangles
A
- 10% carriers
- SILENT carriers
- Maintained in the Guttural pouch
25
Complications of Strangles
- Dyspnea/dysphagia
- Metastatic abscessation (AKA Bastard strangles)
- Myositis (poorly understood; if occurs, SUPER POOR PROGNOSIS)
26
Purpura hemorrhagica and Strangles
- Vasculitis
- Painful edema
- Immune complex formation
- High antibodies
- If exposed and get the vaccine
27
What should you do prior to vaccinating for Strangles if your owner decides to do that, and what are you trying to prevent?
- Measure antibodies
| - If >1:3200, risk of purpura hemorrhagica
28
Diagnosis of Strangles
- Culture or PCR of the discharge
- GP lavage
- Nasopharyngeal WASH
- DO NOT DO A NASOPHARYNGEAL SWAB
29
How to determine if a horse has cleared Strangles?
- 3 negative cultures done every 2-3 weeks
30
What protein does S. equi equi use to avoid phagocytosis?
- M protein
| - SeM ELISA is for the antibody against the M protein
31
ELISA for Strangles - what is it looking for? /
- Antibody against the SeM protein
32
Immunity if you give penicillin to a horse with a fever in a Strangles outbreak
- They won't get the abscess, but they also won't get immunity
- NSAIDs
33
Purpura and myositis treatment
- No need to give antibiotics
- Corticosteroids
Supportive care
34
Immunity post infection of Strangles
- 75% immune >5 years
35
Vaccines for Strangles
- Make sure you measure antibodies first
- IM has a poor efficacy with the M protein extract
- Intranasal MLV only to healthy horses <1 year old (not to foals; strain different than field; local immunity)
36
Clinical signs for recurrent airway obstruction
- Respiratory distress at rest that is EXPIRATORY
- Heave line
- Weight loss (chronic problem)
- No signs of infection (e.g. no fever)
- Older horse (>7 years old)
- Often worse in the winter, spring, and summer
37
Pathogenesis of RAO
- Allergen --> lymphocytes --> neutrophils --> bronchospasm, mucus plugs, smooth muscle hyperplasia, airway wall thickening, fibrosis
38
Diagnosis of RAO
- Bronchoalveolar lavage (>25% non-degenerative NT)***
- Curschmann's spirals
- Maybe atropine to see if they get better
39
Treatment for RAO
- No cure: progressive (you must tell the owner)
- Minimize exposure to antigen
- Medical treatment with steroids (prednisOLONE or dexamethasone; fluticasone) and bronchodilators (clenbuterol, albuterol)
- Environmental management (decrease straw, feed on the ground, wet steam hay; clean)
- During transport, don't tie them up
40
Prognosis of RAO
- Exacerbations
- Always susceptible
- Advanced changes suggest euthanasia :(
41
Interstitial Airway Disease physical exam findings
- Normal auscultation of heart and lungs, thoracic ultrasonography, blood work
42
Interstitial Airway Disease Signalment
- younger racehorses (Thoroughbred)
43
Clinical signs and history of Interstitial Airway Disease
- Poor performance
- Delayed recovery
- Increased effort
44
Diagnosis of Interstitial Airway Disease
- Exclusion diagnosis
- Endoscopy may visualize mucus
- Bronchoalveolar lavage and cytology (NT >5-10% BUT NOT as high as 25%; Mast cells >2-5%; EO >1-5%)****
45
Treatment for Interstitial Airway Disease
- Corticosteroids
- Rest
- Environmental changes
- IFN gamma maybe
46
Exercise Induced Pulmonary Hemorrhage signalment
- younger TB colt
| - Racehorses, barrel horses, polo ponies, etc.
47
EIPH clinical signs
- Few drops of blood from nostrils can be unilateral or bilateral
- Often post exercise
48
Diagnosis of EIPH
- Post-work Endoscopy
| - Blood in esophagus, possible RBCs or hemosiderin on BAL
49
EIPH pathogenesis
- Capillary stress failure
| - Maybe high transmural pressures and high capillary pressures combined with a negative intra-thoracic pressure
50
Treatment of EIPH
- None really
- Furosemide might help, by reducing volume
- Don't do nasal strips
51
Which EHV is associated with abortion?
- EHV-1!
| - 1 is more severe
52
Diagnosis of EHV
- Best to do a PCR on a 6" nasal swab and blood (purple top)
- Can do a test on the fetus too
- Serology possible, but takes too long
53
How soon after infection do horses shed EHV1?
- 1-3 days after infection
- BEFORE they get fever
- By the time they have fever, everyone is exposed
54
Clinical signs of EHV-1
- Biphasic fever (very high)
- Younger horses (yearlings and weanlings)
- Serous nasal/ocular discharge
- Submandibular LN sswelling
55
When in gestation does EHV-1 cause abortions?
- LATE in gestation
56
Vaccination for EHV-1
- Vaccinate!
- Every 6 months if <5y or >5y and high risk
- MLV in foals >3 m
57
Transmission of equine viral arteritis
- Semen
- Urine
- Respiratory secretion
58
Who is the inapparent carrier for EVA?
- The stallion
| - Mares can clear in 28 days
59
EVA replication
- Endothelial cells
- Replicates in macrophages
- Results in vasculitis
60
Clinical signs for Equine Viral Arteritis
- High fever
- Lethargy
- Conjunctivitis
- Cough
- Dyspnea
- Ventral edema (vasculitis)
- Fatal pneumonia in neonates
61
Diagnosis of EVA
- Nasopharyngeal swab or conjunctival swab
- Blood (EDTA) during viremia
- Fetal tissues
62
Positive EVA
- Notify state vet
- Suspend breeding
- Quarantine
63
Positive EHV-1 or EHV-4
REPORT
64
Treatment of EVA
- If severe hind limb edema may want to give furosemide
| - Can do wraps as well
65
Vaccination for EVA
- No US eradication
| - Consult state vet for vaccine because you can't tell it apart from the infection
66
What is the agent of equine influenza?
- H3N8
67
Who is extremely susceptible to equine influenza?
- DONKEYS
- Yearlings too
- leads to many outbreaks
68
Clinical signs of Equine influenza
- Biphasic fever (2nd fever due to secondary infection)
- Limb edema
- 2° bacterial infection!!** (2-3 weeks later, because it replicates in the epithelium of the respiratory tract and decreases clearance)
- Serous nasal discharge
69
Diagnosis of equine influenza
- PCR on nasopharyngeal swab or TTW
- ELISA Stall side test
- Virus isolation on a swab
- Serology (takes too long)
70
Positive equine influenza result
- Notify state vet
- Quarantine 21 d after last clinical case
- Strict biosecurity
- Treatment is same as others
71
Prevention of equine flu
- Vaccine every 6 months
- 4-6 weeks pre-foaling
- Foals 3-6 months
- Boost in an outbreak
72
Vaccine types and pregnancy
- Inactivated (okay for pregnant; will pass to offspring)
- Canarypox vector (okay for pregnant; will pass to offspring)
- Intranasal (MLV; does not pass to offspring)
73
Signs of pleurodynia
- Shallow breathing
- Reluctant to move
- Elbows abducted
- Intolerant to rebreathing exam
- Painful to percussion, pressure on thorax
- Painful coughing
74
Clinical signs of pleuropneumonia
- Pleurodynia
- Dyspnea
- Elevated temperature (but not extremely high)
- Signs of pneumonia (crackles, wheezes, tachypnea, fever; absent sounds)
- Ventral edema
- Dyspnea
75
#1 cause of pleural effusion in horses
- Extension of pleuropneumonia (#1 by far)
76
Pleuropneumonia risk factors
- History of travel (>4 hr) or anesthesia
- Previosu condition like respiratory virus or choke
- All ages
77
Pathogenesis of pleuropneumonia if extension of pneumonia
-- Sterile inflammatory exudate into the pleural space followed by bacteria
- Fibrin can deposit there normally; chronically turns into fibrosis
- Fibrin serves as a nidus for bacterial development
- Usually bilateral
78
Diagnosis of pleuropneumonia
- Clinical signs
- Thoracic ultrasound
- Drain + thoracic radiographs
- TTW: culture and cytology*********
- Pleural fluid may be sterile
79
What is the gold standard for pleuropneumonia diagnosis?
- TTW with culture and cytology
80
Signs on TTW cytology for pleuropneumonia
- Elevated protein
- Low glucose
- Degenerative neutrophils
- +/- bacteria
- 75,000 cells/µL
81
What is the most common isolate of pleuropneumonia in horses?
- Bacteroides fragilis is #1 isolate by far
82
Treatment for pleuropneumonia in horses?****
- Drain chest and leave a chest tube
- K Penicillin (Gram positive and anaerobes)
- Metronidazole (Bacteroides)
- Gentamicin (after hydrating, for gram negative)
- Flunixin
- Can give inhaled antibiotics; oxygen; may need lavage, rib resection, thoracotomy
83
Blood work for pleuropneumonia indicating inflammation
- Neutrophilia
- Monocytosis (chronic)
- Thrombocytosis (inflammation)
- Hyperfibrinogenemia (Inflammation)
- Hyperglobulinemia (chronic)
84
Complications of pleuropneumonia
- Laminitis, thrombosis, sepsis/endotoxemia/diarrhea
85
Prognosis for pleuropneumonia
- Survival is only 40-78%
- Expensive
- Worse if anaerobic bacteria
86
Neonatal pneumonia causes
- Systemic infection (in utero; post-partum)
- Aspiration (weakness; dysphagia)
- Otherwise less common)
87
Commonly implicated bacteria in neonatal pneumonia
- Gram negatives (E. coli, Klebiella, Actinobacillus; Streptococcus zooepidemicus)
88
Risk factors for neonatal pneumonia
- FPT
- Placentitis
- Prematurity
89
Gold standard for diagnosis of neonatal pneumonia
- Blood culture
- Auscultation can be MISLEADING!!!)
- Most foals are too sick for TTW culture and cytology
90
Treatment of neonatal pneumonias
- Treat the primary condition
- Broad spectrum antibiotics
- Anti-inflammatories
- Intranasal oxygen
- CAREFUL WITH bronchodilators
91
Which antibiotics to use in neonatal pneumonia?
- K penicillin (gram positive and anerobes)
- Amikacin (gram negative; hydrate)
- Unlikely to do metronidazole as a first choice
92
Atypical interstitial pneumonia signs and mortality
- <6 months respiratory distress
| - High mortality
93
EHV-1 Pneumonia
- Weak foal
- Progressive pneumonia
- Secondary bacteria
- Look for other signs at the farm
94
Pneumocystis carinii diagnosis and treatment
- Diagnose with cytology
| - TMS treatment
95
Adenovirus what should you suspect if you diagnose in a foal?
- Underlying condition: e.g. SCID!
- Arabians
- Immunosuppressed foals
96
Signs that a foal never stood up after foaling?
- Have epomicium
| - Covering on the hoof
97
Older foal pneumonia likely etiology
- Streptococcus zooepidemicus
98
Physical exam findings for an older foal pneumonia
- Slight fever
- May have a slightly elevated heart rate
- BAR often but dyspneic
- Often can't hear abnormal lung sounds
- Agitated and not nursing well
- 1.5 months old ish
99
Diagnosis of pneumonia in an older foal
- Ultrasound is helpful
| - Can see a consolidated lung on ultrasound
100
Antibiotic for Streptococcus zooepidemicus
- Penicillin
101
What signs on bloodwork are indicative of an abscess?
- High fibrinogen and high globulins!!!
102
What is one of the features of Rhodococcus equi that makes it pathogenic?
- Vap A protein (allows it to escape macrophages
103
Who gets R. equi?
- Young foals
- Immunosuppressed adult horses
- Infected early in life
- If ingested, diarrhea; if inhaled, pneumonia
104
Clinical signs of R. equi
- Febrile
- Tachycardic
- Dyspneic
- Lethargic
105
Extrapulmonary lesions with R. equi
- Ulcerative colitis (Diarrhea)
- Ulcerative lymphangitis
- Arthritis/osteomyelitis (BAD NEWS)
- Abscesses
- Immune mediated polysynovitis, thrombocytopenia, anemia
106
Diagnosis of R. equi
- Can see an abscess on the ultrasound
- Bloodwork with a high fibrinogen and high globulins will suggest abscess
- TTW is definitive diagnosis; cytology and culture; PCR for VapA
- Need a positive culture plus a septic neutrophilia!
107
Treatment of R. equi
- 80% don't need treatment
| - Often if small enough, don't need treatment
108
Treatment of R. equi
- Macrolides + rifampin
| - Azithromycin example
109
Warnings for treatment
- Watch out for hyperthermia
| - Will also urinate orange
110
Prevention
- Small abscesses no treatment
- Clinical pneumonia (Antibiotics and NSAIDs)
- No vaccine
- Hyperimmune plasma may help?
111
Hyperimmune plasma for R. equi
- At birth - dose?
- Decreases severity
- Expensive
112
Parascaris equorum age affected and clinical signs
- Weanlings (4m-1 year)
- Occasional cough
- No other signs
- Self-limiting
- Migration phase in lungs leads to inflammation and eosinophils
113
Diagnosis for parascaris equorum
- TTW and BAL (eosinophils and larvae)
| - Non-specific blood work
114
Treatment for Parascaris equorum
- Fenbendazole
- Multiple doses
- Be really careful because if the worms die all at once, can cause an impaction
