8.2.2: Pleuropneumonia Flashcards
Pneumonia
Infection of the lower respiratory tract
Bronchopneumonia
Infection of the bronchi and parenchyma
Pleuropneumonia
infection of the lower respiratory tract that extends to the pleural space
What are the stages of pleuropneumonia?
- Exudative stage - sterile transudate increased in the pleural space
- Fibrinopurulent stage - bacterial invasion and fibrin deposition
- Organisation stage - fibroblasts grow into the exudate (pleural peel)
What pathogens might be involved in pneumonia in horses?
- Streptococcus equi subsp. Zooepidemicus = most common
- Staphylcoccus aureus, Staph pneumoniae
- Actinobacillus spp. (gram -ve non-enteric)
- Escherichia coli, Pasteurella spp., Enterobacter spp., Klebsiella spp., Bordetella bronchiseptica
- Bacteriodes fragilis
- Fusobatcerium and Peptostreptococcus anaerobius
Clinical signs of pneumonia
- Tachycardia/ tachypnoea
- Respiratory distress
- Fever
- Anorexia
- Depression
- ± nasal discharge
- Exercise intolerance
- Crackles and dull areas on auscultation
Clinical signs more specific to pleuropneumonia
- Pain in the intercostal space
- Reluctance to walk, colic
- Grunting during respiration
- Abduction of elbows
- Ventral oedema
Lung sounds suggestive of pneumonia/ pleuropneumonia
- Crackles and wheezes
- Dull areas
- Dull area following a flat line (pleuropneumonia)
- Pleural rubs (pleuropneumonia)
- Radiation of cardiac sounds to areas well outside the typical areas (this occurs when there is lots of fluid/ pleural consolidation around the heart)
Diagnosis of pneumonia/ pleuropneumonia
- Suspicion based on physical exam and rebreathing bag
- Haematology and biochemistry
- Endoscopy
- Trans-tracheal wash and BAL
- Thoracic ultrasound
- Thoracic radiography
- Thoracocentesis
- Thoracoscopy
Clinical pathological findings with pneumonia
- Neutrophilic leukocytosis
- Leukopaenia
- Anaemia (seen in chronic cases)
- Increased fibrinogen and SAA (= systemic inflammation)
- Decreased Fe2+
Discuss the use of TTW for suspected pneumonia
Trans-tracheal wash
* Extremely useful in suspected pneumonia
* Culture and sensitivity - best if percutaneous TTW; can do aerobic and anaerobic culture, if so do not fridge anaerobes
* Can get cytology representation of both lungs
* Obtain this even if pleural fluid is also available for culture
* Consider the impact of concurrent antibiotics the horse might be on
What might you see on endoscopy of a horse with pneumonia? What might this look like?
- Might see lots of mucus - this is characteristic of bacterial pneumonia, equine asthma.
- With a long endoscope, can try to identify the affected side/bronchi; and can see if there is an abscess draining into a bronchus
Describe the findings on this thoracic ultrasound, including the structures 1 and 2
1 - intercostal muscles
2 - pleural and lung surface
There is a defect in the pleura with comet tail below it - this could be pathology, or just an older horse.
Describe the findings on this thoracic ultrasound.
Several areas of pulmonary consolidation
Ultrasound is best for imaging which areas of the lungs?
The lung periphery/surface and pleura. If there is anything further in, might not be able to reach and image.
Describe the findings on this thoracic ultrasound.
- This lung is consolidated - we can see further medially than the pleura, which is unusual.
- Can see full thickness of the tip of the lung (not normal!)
- A small amount of gas in the lung creates a hyperechoic artefact.
Describe the findings on this thoracic ultrasound.
There is consolidated lung without air in it.
Describe the lung pattern and pathology on these radiographs
- Bronchoalveolar lung pattern
- There is a fluid line visible
- This is a horse with pleuropneumonia
Describe the lung pattern shown here
Multinodular bronchoalveolar pattern
Describe the pathology shown here
This is a horse with a pulmonary abscess
