resp pathology Flashcards
What type of fluid is this and what is this condition called?
-sero-sanguinous transudate
hydrothorax
what can cause a hydrothorax?
CHF
What has hapenned to the dark areas of lung?
congested and deflation (atelectasis)
what diseases can cause congestion and atelectasis?
thoracic cavity tumour
pneumothorax
haemothorax
pyothorax
abscess
inhaled fb / food
What is the major abnormality present in image A?
emphysema - diffuse alveolar and interstitial
What major abnormality is seen in image B?
- flooding of alveoli with protein rich fluid
- widened interlobular septa with fibrin
what cattle disease can cause emphsema and alveoli flooding with protein rich fluid?
Acute bovine pulmonary oedema and emphysema (fog fever)
- lush autumn grass has tryptophan which converts to a pneumotoxin in the rumen
name 4 features of the upper and lower resp tract that protect the lung from airborne infections?
- mucociliary escalator
- mucus
- nasal cavity with turbulent air flow
- resident alveolar macrophages
what area of the resp tract is most vulnerable to infection?
where cilia end before alveoli
(bronchoalveolar junction)
What portion of the lung is affected and what has hapenned to it?
- Cranioventral distribution on each lobe
- dark bit = consolidation and congestion (chronic pneumonia)
what is the condition shown?
bronchiolectasis = permenant bronchiole dilation
What is illustrated in image B?
artery and bronchiole infiltrated in wall and lumen by inflammatory cells
neutrophils and purulent exudate stretch the bronchiole and fix it as dilated
How do the changes in image A develope from the changes in image B?
-damaged smooth muscle so stay dilated
what is the blue material that is asteriksed within the airway lumen?
thick mucous plugging the airways
can also see excess goblet cells and hyperplasia of the wall so reduced cilia so cant clear mucous
This is from a stabled horse with a chronic history of dyspnoea and coughing. What is the most likley diagnosis?
RAO
How can you alleviate the symptoms of RAO?
- soak hay
- good hay quality
- change bedding to mats
- turn horse out
- mucolytics
- bronchiodilators
- expectorants
- NSAIDs, steroids, anti-histamines
What is the obvious abnormality and what do we call this in neonates?
- light and dark patchy appearance
- primary partial atelectasis
- it has taken a few breaths as some areas inflated
What is the difference between the two images?
Top = normal
Bottom = pink protein rich exudate - oedema
What can cause pulmonary oedema?
LS HF
brain injury
symp stimulation
tryptophan
smoke
paraquat
iatrogenic - excess fluids
barbiturate euthanasia
A = normal
B and C = abnormal
c= more magnified
What is the difference in B and C?
- pink exudate and no air in alveoli
- neutrophils present
What two patterns of pneumonia are characterised by the changes in B and C?
bronchopneumonia - infl cells in air space, inhaled
Embolic - from blood
Describe the gross appearance of the lungs
Large variably sized cream - yellow nodules
Granuloma or abscess
what is the difference in cell type between a granuloma and abscess?
Granuloma - macrophage
Abscess - neutrophil
What does image A show?
necrotic centre with viable macrophages then lymphocytes then capsule
- a granuloma
- dark foci = dystrophic mineralisation due to necrosis
What cell is indicated by the asterisk in image B?
multinuclear giant cell
(fused macrophages)
How can you confirm Tb presence?
ziehl - neelson stain - see magenta bits in macrophages
What are the pathological changes with Tb?
giant cells
granulomas
What pigment do all these lesions have in common?
Melanosis
-flat nodule
what is the gross abnormality?
Mucopurulent exudate
diffuse redenning (hyperaemia / congestion / haemorrhage)
sulphur granules in exudate
what is the most likely undelrying cause?
Norcardia or actinomyces as make sulphur granules
- from environment from cat fight wound
What has hapenned and what is this condition called?
Atrophic rhinitis
- bilateral concha loss, smaller turbinates and wonky snouth
- tear staining
- more prone to secondary infection
What pathogens cause atrophic rhinitis and how do they work?
- pasturella multocida - activates osteoclast
- bordatella bronchiseptica - inhibits osteoblasts
Describe the macroscopic changes in the lung? What are 3 possible causes?
White nodules on very dark red lung - atelectasis
- neoplasia
- granuloma
- abscess
What is the underlying cause?
Glandular (cells stuck to neighbouring cells and forming lines) neoplasia
- adenocarcinoma
what is the most likely parasite causing this infection?
Dictycalus viviparus
what is the likley immune status of this calf to the parasite?
Been exposed before as formed a type 4 hypersensitivity granuloma