Pulmonary disease Flashcards
1
Q
What are the various pulmonary disorders (list–9)?
A
- Pneumonia
- Eosinophilic bronchopneumopathy (EBP)
- Pulmonary neoplasia
- Pulmonary edema: non-cardiogenic
- Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS)
- Pulmonary contusions
- Pulmonary thromboembolism (PTE)
- Idiopathic pulmonary fibrosis (progressive interstitial fibrosis)
- Lung lobe torsion and diaphragmatic hernias
2
Q
Pulmonary disease–clinical signs
A
- Difficulty breathing–often expiratory pattern
- Inc. rate and effort
- Coughing
- Exercise intolerance
- Abnormal pulmonary sounds
- Compare to pleural disease
- Abnormal posture–orthopnea
3
Q
Pneumonia
Overview
A
- Inflammatory disorder of pulmonary parenchyma
- Etiology (infectious)
- Bacterial–most common cause in dogs
- Viral–most common cause in cats
- Aspiration
- Fungal
- Parasitic (Paragonimus spp, Aelurostrongylus spp)
4
Q
Pneumonia
Radiographs?
Characterized by?
Other clinical signs?
A
- Radiographic pattern helps distinguish dif. etiologies
- Characterized by soft, ineffectual cough
- Difficulty in breathing on expiration (animals often have both inspiratory and expiratory attern), dyspnea, tachypnea, cyanosis if severe
- Other clinical signs
- Nasal discharge
- Exercise intolerance
- Systemic signs–pyrexia, lethargy, anorexia
5
Q
Bacterial pneumonia
More common in?
What occurs?
Primary bac. pneumonia?
A
- More common in dogs than cats
- Inflammation and consolidation of pulmonary tissue occurs
- Primary
- Younger dogs
- Bordetella
- Pasteurella
- Younger dogs
6
Q
Bacterial pneumonia
Secondary bac. pneumonia
If history of recent sedation/anesthesia?
A
- Secondary bac. pneumonia
- Often older animals
- Aspiration
- Iatrogenic, loss of normal airway protection, megaesophagus, cleft palate, nasogastric tube, laryngeal paralysis, consciousness: anesthesia or neuro disease
- Foreign body (not common in lung tissue)
- Neoplasia
- Viral or fungal infection
- Bronchitis
- If hx of recent sedation/anesthesia, organism most likely is more resistant b/c it is assoc. w/ hospital infection; hospital/super bug
7
Q
Bacterial pneumonia
Diagnosis
A
- Hematology
- L shift neutrophilic leucocytosis
- Monocytosis if more chronic
- Thoracic rads
- Interstitial pattern early in disease
- Alveolar pattern: air bronchograms are classical
- Often assoc. w/ R middle lung lobe pathology or cranioventral distribution
- Look for foreign bodies, megaesophagus, and other thoracic disease
- Radiographic changes lag behind clinical signs
- Transtracheal/endotracheal wash and cytology/culture
- Bronchoscopy w/ BAL and culture/cytology
- Can direct endoscopy to the lesion
- Usually get BAL samples from R middle and L caudal lung lobes (unless pus is visible elsewhere)
- Cytology–degen. neut, monocytes, intracellular bac.
- Bac. pneumonia can result in sepsis which can lead to ALI and ARDS (death)
8
Q
Bacterial pneumonia
Treatment: antibiotics
A
- Begin empirical treatment pending culture results
- Broad coverage
- 4 quadrants: gram (+), (-), anaerobes, Mycoplasma spp
- Begin w/ injectable therapy, then change over to oral medication once under control
- Long-term therapy usually required–4-8wks, esp. if secondary
9
Q
Bacterial pneumonia
Treatment: nebulization
Supportive care
A
- Nebulization
- Travels all the way down to lungs–> attaches to pus–> easier for animal to cough it up
- Mobilizes airway secretions
- Sterile saline +/- gentamycin
- May result in bronchoconstriction, may need to use a bronchodilator before nebulization
- Supportive care
- IV fluids, O2 therapy, and coupage
- Bronchodilators if required
10
Q
Mycotic pneumonia
Etiology
A
- Blastomycosis
- Histomycosis
- Coccidiomycosis
- Aspergillosis
- Others
11
Q
Mycotic pneumonia
Respiratory clinical signs
A
- Similar for all (chronic)
- Abnormal resp pattern
- Tachypnea
- Cough
- Exercise intolerance
- Systemic signs
- Inappetance, weight loss, fever, lameness, lymphadenopathy, chorio-retinitis or anterior uveitis, draining fistula tracts
12
Q
Mycotic pneumonia
Diagnosis
Treatment
A
- Diagnosis
- Urine or serum ag titres
- Cytology/histopathology (biopsy)
- Treatment
- Depends on fungal sensitivity
- Polyene antifungals–amphotericin B ($$$)
- Triazoles–itraconazole, posaconazole, voriconazole, fluconazole
- Imadazoles–clotrimazole, ketoconazole
13
Q
Mycotic pneumonia
How to tell which fungal organism is causing the clinical signs?
A
- Geographical location
- Coccidiomycosis–Arizona
- Blastomycosis/Histoplasmosis–Ohio river valley
- Difference in clinical signs or organs that are affected
- GI signs–histoplasmosis (+/- organism on rectal scrape)
- Cytology–lymph nodes, draining lesions, TTW, ETW, BAL, pulmonary aspirate
- Serology
- Serum antigen titre for Cryptococcus spp., Aspergillosis spp.
- Urine antigen titre for blastomycosis and histoplasmosis and valley fever (Miravista lab), Aspergillosis
14
Q
Mycotic pneumonia
Treatment
A
- Expensive and long-term (4-12 mo)
- Oral medications
- Itraconazole more costly, fluconazole generics now avail.
- Posaconazole very $$–less hepatotoxic, esp. for cats
- Voriconazole very $$
- Side effects: inappetance, elevated liver enzymes
- IV/SC
- Amphotericin B–nephrotoxic (monitor BUN and Cr)
- Lipid complex form is more $$ but has fewer side effects, less nephrotoxic
- Amphotericin B–nephrotoxic (monitor BUN and Cr)
15
Q
Mycotic pneumonia
Prognosis
A
- How disseminated is the infection
- Poorer prognosis if CNS is involved
- 1st week of treatment–greater chance of worsening resp signs
- Blastomycosis and cryptococcus–80% effectively treated
- Histoplasmosis–disseminated form has guarded prognosis, localized form has better prognosis
- Coccidiomycosis–60% recovery rate but medication often needed for 6-12 mo or longer (lifelong)
16
Q
Blastomycosis
Geographical distribution?
Mode of infection?
Location in body?
A
- Distribution–North America
- Mississippi, Missouri and Ohio river valleys, Mid-Atlantic states and Canadian provinces of Quebec, Manitoba, and Ontario
- MOI
- Inhalation of spores from mycelial growth in environment
- Blastomyces dermatitis establishes in the lungs then disseminates throughout body
- Lungs
- Skin, eyes, bones, LN, SQ, nares, brain, testes
17
Q
Blastomycosis
Clinical findings
A
- Often show no clinical signs–but then the signs develop and worsen very quickly
- 40-60% w/ fever
- Emaciated
- Lymphadenomegaly common
- 85% w/ dry harsh cough
- Exercise intolerance
- 40% w/ ocular lesions–uveitis, iridic hyperemia, aqueous flare, myosis, chorioretinitis, optic neuritis, retinal detachment
- 20-50% w/ skin lesions
- 30% w/ bone lesions
18
Q
Blastomycosis
Diagnosis
A
- Imaging–rads, U/S, MRI
- Hematology and biochemistry
- Chronic anemia
- Moderate leucocytosis w/ L shift + lymphopenia
- Hyperglobulinemia
- Hypercalcemia
- Cytology or histopathology
- LN, skin lesions, TTW (69-76% sensitive), FNA of lung (81% sensitive) (pot. risk of pneumothorax w/ FNA)
- Serology
- PCR available
19
Q
Blastomycosis
Diagnosis–serology
A
- AGID test
- Serum and urine samples
- 41-90% sensitive
- 90-100%
- Radioimmunoassays for Blastomyces
- 92% sensitive
- ELISA on urine
- 93.5% sensitive; also cross-react w/ histoplasma and blastomyces
20
Q
What is this?
A
Blastsomyces dermatitis
21
Q
Blastomycosis
Pathological findings?
Therapy?
A
- Pathological findings–pyogranulomatous lesions
- Therapy
- Amphotericin B
- Nephrotoxic–give slowly through IV
- 0.5mk/kg every other day
- Accumulated dose of 8-10mg/kg is required to cure blastomycosis
- Comes in lipid complex (less toxic)
- Costs more, high dose required
- Amphotericin B
22
Q
Blastomycosis
Treatment
A
- Triazole
- Itraconazole
- Oral administration 5mg/kg OD for dogs, TD for cats
- In dogs start w/ TD administration for 5 days to inc. serum conc., then reduce to OD
- 60-90 days administration
- 68% response rate
- Adverse effects, anorexia assoc. w/ hepatotoxicity
- Oral administration 5mg/kg OD for dogs, TD for cats
- Itraconazole
23
Q
Histoplasmosis
Epidemiology
A
- Histoplasma capsulatum
- Worldwide
- Midwestern and Southern US
- Regions along Mississippi, Missouri and Ohio river
- Likes soil that is high in bird or bat feces
- Midwestern and Southern US
24
Q
Histoplasmosis
Clinical findings: dogs vs. cats
A
- Cats
- 2nd most common systemic fungal disease
- Disseminated dz
- Mental depression, wt. loss, fever, anorexia, pale mm
- Coughing uncommon, but dyspnea, tachypnea, and abnormal lung sounds are found
- Dogs
- Inappetance, wt. loss, fever unresponsive to antibiotics
- Signs can be limited to resp tract–dyspnea, coughing, abnormal lung sounds
- Signs are generally disseminated
25
**Histoplasmosis**
Diagnosis
* Hematology
* Chronic anemia
* Thrombocytopenia (50% dogs, 33% cats)
* Leukocyte counts vary--often get neutrophilic leucocytosis, monocytosis, and eosinopenia
* Biochemistry--may show hypoalbuminemia
* Imaging--rads, U/S
* TTA/BAL (cytology)
* Organism found w/in mononuclear-phagocyte system
* Single or multiple organisms
* FNA/biopsy--cytology/histo
* Serology--**no test is reliable**
26
What is this?
Histoplasmosis
27
**Histoplasmosis**
Therapy
* **Itraconazole treatment of choice**
* ****10mg/kg once to twice daily (some cats)
* Treat 4-6mo
* Fluconazole
* Better penetration into brain and eye (good for cats w/ neuro signs)
* But not that effective
* Voriconazole and posaconazole
* Penetrates **blood brain barrier**
* Amphotericin B used in severe cases
28
**Cryptococcosis**
Etiology/epidemiology
* *Cryptococcus neoformans* and *C. gattii*
* Worldwide
* *C. neoformans*
* **Usually assoc. w/ avian droppings
* *C. gattii*
* **Assoc. w/ Eucalyptus trees
* Also found in British Columbia and California
29
**Cryptococcosis**
Clinical findings (cats and dogs)
* Animals often immunosuppressed
* Cats
* Chronic infection, chronic listlessness, wt. loss, poor appetite
* Bilateral nasal discharge, snuffly
* Firm to flucuant swelling over bridge of nose
* Lymphadenopathy--mandibular
* Neuro signs if CNS affected, ocular lesions
* Dogs
* Frequently have disseminated dz
* 2/3 have neuro signs
30
**Cryptococcosis**
Diagnosis
* Hematology and biochemistry
* Usually non-specific
* Cytology
* Nasal swab, nasal wash, FNAs, BAL, pleural fluid, CSF, urine
* Thick capsulated yeast
* Tissue biopsy
* Fungal isolation
* **Easy to grow**
* Serology
* Serum, CSF
* Latex-agglutination procedure test (90-100% sensitive, 97-100% specific)
* Nucleic acid detection
* PCR--highly sensitive and specific (only used if other methods fail)
31
What organism is this?
*Cryptococcus spp*
| (Cytology on L, histopathology on R)
32
**Cryptococcosis**
Treatment
* Surgery
* Therapy (long--8-9mo)
* Amphotericin B
* Fluconazole--10mg/kg BD
* Itraconazole--10mg/kg OD
* Voriconazole and posaconazole
* Monitoring
* Use LAT--antigen titre should drop at least one dilution (2 fold) per month during effective treatment
* Continue therapy until LAT is negative
33
**Coccidioidomycosis**
Organism?
Environment?
Epidemiology?
Known as?
* *Coccidioides spp.*
* Likes dry environment
* Epidemiology
* Southwestern US
* A few places w/in South America
* "Valley fever"
34
**Coccidioidomycosis**
Clinical findings?
* Dogs
* Dry, harsh cough--usually due to hilar lymphadenopathy or diffuse pulmonary interstitial disease
* Fever, partial anorexia, wt. loss, weakness, lameness
* Can become disseminated
* Cats
* Similar signs as dogs, but the cutaneous lesions are most common in cats
35
**Coccidioidomycosis****--diagnosis**
Hematology?
Imaging?
* Hematology
* Non-regenerative anemia
* L-shift neutrophilia and monocytosis
* Eosinophilia--variable
* Imaging
* Thoracic rads
* Diffuse interstitial pattern
* Miliary to nodular interstitial densities
* Solitary nodules
* Hilar lymphadenopathy
* U/S
* MRI
36
**Coccidioidomycosis--diagnosis**
Cytology/histopathology
Fungal culture
Serology
* Cytology or histo
* Organism found along w/ pyogranulomatous inflammation
* Round, double-walled structure containing endospores
* Fungal culture--difficult, use proper labs
* Serology
* Tube precipitation antigens (less use today)
* Body produces IgM antibodies
* Complement fixation antigens (less use today)
* Body produces IgG antibodies
* Latex agglutination for IgM or IgG
* AGID test for IgM or IgG--antibodies
* Elisa test for IgM or IgG--antibodies
37
What organism is this?
*Coccidioides spp*
38
**Coccidioidomycosis**
Treatment
Prognosis
* Treatment
* Azoles
* 3-6mo **past resolution of clinical signs**
* Ketoconazole, itraconazole, or fluconazole
* Prognosis
* Good for resp disease
* Poor for disseminated disease
39
**Parasitic pneumonia**
Two main worms (cats/dogs)?
* *Aleurostrongylus abstrusus* (cat lungworm)
* Larvae may be found in feces
* TTW/ETW--cytology
* BAL--cytology
* *Paragonimus kellicoti* (dog/cat lung fluke)
* Operculated egg
40
***Aleurostrongylus abstrusus***
What is it?
Signs?
Diagnosis?
Treatment?
* Feline lungworm
* Can have subclinical to clinical signs similar to asthma
* Usually younger cats
* Diagnosis
* Hematology--poss. eosinophilia
* Thoracic rads--diffuse nodular densities, caudal lobes
* TTW/BAL--inc. # of eosinophils and/or larvae
* Fecal--larvae evident
* Treatment
* Fenbendazole
* Ivermectin
41
***Aleurostrongylus abstrusus***
Life cycle?
42
***Paragonimus spp.* pneumonia**
Signs?
What forms?
Possible end result?
* Can be subclinical or clinical--cough, wheeze, or resp distress
* Flukes form cysts w/in lungs
* Cysts can easily rupture--\> pneumothorax
43
***Paragonimus spp* pneumonia**
Diagnosis?
* CBC--eosinophilia
* Thoracic rads--air-filled cysts
* TTW/BAL
* Fecal--**zinc sulphate fecal float**
* **Operculated egg**
44
***Paragonimus spp***
Life cycle?
45
**Idiopathic pulmonary fibrosis--progressive interstitial fibrosis**
What is it?
Signalment?
* Chronic fibrosis of the lung interstitium characterized by infiltration of fibroblasts; collagen deposits in alveolar septa
* Signalment
* West Highland White Terrier
* Middle or older
* Some cats
46
**Idiopathic pulmonary fibrosis--progressive interstitial fibrosis**
History?
Clinical signs?
* History
* Slow onset, exercise intolerance
* Clinical signs
* Depends on severity, resp distress, tachypnea
* Coughing increases as it progresses
* Wt. loss in cats
47
**Idiopathic pulmonary fibrosis--progressive interstitial fibrosis**
Diagnosis
* Very difficult
* Inspiratory crackles on auscultation (**hallmark**)
* Thoracic rads
* Generalized or diffuse interstitial pattern
* Arterial blood gas
* Hypoxemia if severe
* TTW/BAL
* Eliminate other differentials
* Epithelial dysplasia? Non-regenerative neut and lymphocytes
* Lung FNA
* **Lung biopsies--definitive diagnosis**
48
**Idiopathic pulmonary fibrosis--progressive interstitial fibrosis**
Treatment?
Prognosis?
* Lack of specific treatment
* Corticosteroids (not very effective alone) + bronchodilators aleviate clinical signs of chronic bronchitis
* Cyclophosphamide or azathioprine?
* Colchicine?
* Prognosis
* Guarded
* Progressive resp failure
49
**Pulmonary neoplasia**
Etiology--primary vs. metastatic vs. multicentric
* Primary
* Adenocarcinoma (alveolar or bronchogenic)
* SCC
* Metastatic
* Many sources
* Adenocarcinoma
* Osteosarcoma/chrondrosarcoma
* Hemangiosarcoma/oral or digital melanoma
* Multicentric
* Lymphoma, malignant histiocytosis, mastocytoma
50
**Pulmonary neoplasia**
Signalment?
Clinical signs?
* Signalment--usually older animals
* Clinical signs
* Wide spectrum
* Respiratory
* Abnormal thoracic auscultation, crackles, wheezes, or muffled sounds
* Cough (from compression), dyspnea, tachypnea, hemoptysis
* Non-resp signs
* Wt. loss, inappetance
* Lameness (hypertrophic osteopathy)
* Dyshagia/regurgiation (MG)
* Edema of head/neck (venous obstruction)
51
**Pulmonary neoplasia**
Radiographs?
Cytology/histo?
* Thoracic rads
* **3 views essential (2 laterals and DV/VD)**
* Assess LN size
* Assess pleural space (pneumothorax, effusion)
* Cytology/histopathology
* FNA--lung/mass
* Bronchoscopy (BAL or biopsy)
* If metastatic find primary mass and sample
52
**Pulmonary neoplasia**
Treatment
Prognosis
* Treatment
* Primary
* Surgical removal--lung lobectomy
* Metastatic/multicentric
* Treat primary mass
* Chemotherapy (lymphoma)
* Prognosis
* Guarded to poor
* If it is a solitary mass or benign mass--prognosis good w/ surgical removal
53
**Pulmonary neoplasia**
Prognostic factors (common sense)
* Benign better than malignant
* Primary better than metastatic
* Adenocarcinoma better than SCC
* Small tumors better than large tumors
* Tumors involving one lobe better than mult. lobes
* No LN involvement is better
54
**Pulmonary edema**
What is it
2 possible origins
* Accumulation of fluid in alveoli or pulmonary interstitium
* Cardiogenic or non-cardiogenic in origin
55
**Non-cardiogenic pulmonary edema**
4 mechanisms?
* Vascular overload/inc. hydrostatic pressure
* IV fluid overload
* Decreased plasma oncotic pressure
* Low albumin
* Increased alveolar-capillary membrane permeability
* Pulmonary insults--aspiration, upper airway obstruction, smoke
* Non-pulmonary insults--sepsis, electric shock, CNS (seizures, head trauma), pancreatitis, DIC
* Lymphatic obstruction
56
**Non-cardiogenic pulmonary edema**
Interference?
Can progress to?
* Fluid accumulation interferes w/ ventilation and perfusion
* Can progress to
* Accute lung injury and/or
* ARDS
* Resp failure
57
**Non-cardiogenic pulmonary edema**
Thoracic auscultation?
Thoracic rads?
Looks for what?
* Hear crackles--caudal/dorsal area
* Thoracic rads
* Alveolar pattern--bilateral
* Caudo-dorsal lung fields
* Looks for underlying disease
58
**Non-cardiogenic pulmonary edema**
Treatment
* Aggressive control of primary/underlying disease
* Cage rest and O2 therapy
* Supportive care
* Sedation--reduce anxiety, O2 requirements and cardiac workload
* IV fluids--**be very careful**
* Positive pressure ventilation--if required
59
**Non-cardiogenic pulmonary edema**
Prognosis
* Guarded w/ permeability edema pathogenesis
* Depends on underlying disease
* Ex: Ehrlichia--more difficult to treat
* Increase alveolar-capillary membrane permability
* Better when there is no fluid overload or renal function is intact
60
**Respiratory distress**
Types?
Commonly secondary to what?
1. Acute lung injury (ALI)--pulmonary inflammation and edema resulting in acute resp failure
2. Acute resp distress syndrome (ARDS)--severe manifestation of ALI; hypoxemia is worse
* ALI/ARDS commonly secondary to sepsis, systemic inflmmatory distress syndrome, sock or bac. pneumonia
* With known FiO2:
* PaO2/FiO2 \< 300 = ALI
* PaO2/FiO2 \<200 = ARDS
* Raised alveolar-arterial O2 gradient
61
**Respiratory distress**
Clinical signs?
Current theray?
Prognosis?
* Clinical signs can be delayed 1-4d after inciting event
* Progressive hypoxemia, resp distress, cyanosis
* Therapy
* Aggressive supportive care that requires ICU
* Positive pressure ventilation
* Prognosis
* Mortality rate very high--close to 100%
62
**Pulmonary contusions**
Various degrees of what?
Thoracic auscultation?
Concurrent pathology w/ trauma?
* Various degrees of resp distress
* Thoracic auscultation--crackles
* Concurrent pathology
* Pneumothorax/hemothorax
* Herniation
* Myocarditis
* Rib fractures
* Hypotension
63
**Pulmonary contusions**
Thoracic radiographs
Treatment
* Radiographic evidence can take 2-12hrs to show up
* Consolidation
* Treatment
* Monitor closely for 24-48hrs
* O2 therapy
* IV fluids
* Pain medication for trauma
64
**Eosinophilic bronchopneumopathy**
What is it?
Antigen?
Signalment?
* Inflammation of lungs--thought to be due to a hypersensitivity to some unknown antigen
* Lots of eosinophils roduced--\>infiltrates to lungs
* Usually the antigen is not detected, but possibilities include:
* HW, lung parasites, drugs, inhaled allergens, neoplasia, fungal, bac. infections
* Signalment
* Siberian huskies predisposed
* Young to middle-aged
65
**Eosinophilic bronchopneumopathy**
Clinical signs
* Harsh cough
* Progressive resp difficulty, exercise intolerance
* Some have nasal discharge or anorexia/lethargy
* Lack of response to antibiotics
66
**Eosinophilic bronchopneumopathy**
Diagnosis
* Thoracic auscultation--harsh crackles, expiratory wheezes
* Tracheal palpation may elicit moist productive cough
* Hematology--50% have inc. neuts or eos
* Ensure HW (-) and fecal float (-)
* Eosinophilia often assoc. w/ parasites
* Pulse oximetry and arterial blood gas
* Hypoxemia can be marked
* Can persist post-recovery
* Thoracic rads
* Diffuse bronchointerstitial pattern, alveolar infiltrates, bronchiectasis
* Cytology--eos predominate (\>20-25%)
67
**Eosinophilic bronchopneumopathy**
Treatment
* Find and treat any underlying disease
* Even if no evidence of lungworms--fenbendazole
* Corticosteroids
* Prednisolone--taper over several months depending on clinical radiographic response
* Often required long-term due to relapses
* Try inhalation steroids
* Other immunosuppressives can be tried--cyclosporin, azathioprine
68
**Pulmonary thromboembolism (PTE)**
Associated with?
* HW
* Immune-mediated hemolytic anemia
* Nephrotic syndrome
* Hyperadrenocorticism--hypercoagulability
* Pancreatitis
* DIC
* Endocarditis
69
**PTE**
Treatment
Prognosis
* O2 supplementation
* No stress
* Treat underlying disease
* Bronchodilators
* Prednisolone in IMHA and HW cases
* Low dose heparin if DIC or hypercoagulable
* Prognosis--poor to grave
