4-Month-Old Female Domestic Shorthair

By Kylie Gamber c/o 2022

Signalment & History

4-month-old female Domestic Shorthair who presented with a 1-week history of progressive lethargy. On physical evaluation, lung sounds are absent in the left ventral thoracic region.


  • Within the left cranial and left caudal lung lobes, there is a severe homogenous increase in soft tissue opacity, which causes border effacement the pulmonary vasculature, the left side of the cardiac silhouette, as well as a portion of the left diaphragmatic crus. Within this soft tissue opacity, there are air bronchograms and small, multifocal, well-defined, smoothly marginated and irregularly shaped gas opacities.
  • The left caudal and cranial lobar bronchi cannot be definitively identified.
  • The ventrodorsal projection is obliquely positioned with mild rightward displacement of the cardiac silhouette. The visualized cardiovascular structures are normal.
  • The cranial abdominal organs have a normal anatomical position.


  • Left-sided alveolar pattern with multifocal gas opacities and mild rightward mediastinal shift. Differentials include severe pneumonia (with possible abscess formation), lung lobe torsion, or diaphragmatic hernia.


The patient underwent a left cranial lung lobectomy. Histopathology of the left cranial lung lobe was consistent with severe diffuse chronic bronchopneumonia (histiocytic-neutrophilic) with proliferative pleuritis.

Given the histopathology finding, bronchopneumonia associated with a chronic infectious process (e.g. bacterial or possibly fungal in nature) was considered primarily.

Bacteria most commonly cultured in primary bronchopneumonia are Bordetella bronchiseptica and Streptococcus zooepidemicusBordetella is highly contagious. In one study, over 60% of cases with pneumonia had more than one bacteria species as part of the infection, hence the importance of culture and antibiotics. Bronchopneumonia can develop secondary to parainfluenza virus or canine adenovirus type-2. Antivirals are not commonly used. Usually the treatment is aimed as secondary bacterial infections.


  1. Maden, M., et al. “Clinical, cytologic, bacteriologic and radiographic analysis of respiratory diseases in dogs.” Veteriner Bilimleri Dergisi1 (2000): 43-50.
  2. Wagener, J. S., et al. “Role of canine parainfluenza virus and Bordetella bronchiseptica in kennel cough.” American journal of veterinary research9 (1984): 1862-1866.