Pneumonia can be caused by
viruses, bacteria, fungi, or parasites. Bacterial and viral
pneumonia are often preceded by an infection in the nasopharynx or airways.
Pneumonia is uncommon in healthy adult dogs. It tends to target the very young and the very
old, and those whose immune systems have been compromised as a result of
corticosteroid therapy, chemotherapy, or chronic
illness. Dogs with chronic bronchitis, collapsing trachea,
or foreign bodies in the lower airway frequently develop bacterial
The leading cause of heart failure in dogs
is chronic valvular disease. Next
is dilated cardiomyopathy, followed by congenital heart disease and heartworms. More infrequent
causes include bacterial endocarditis and myocarditis. Coronary artery disease
is rare in dogs. It occurs only in dogs with severe hypothyroidism accompanied by
extremely high serum cholesterol levels.
Inhalation or aspiration pneumonia occurs with megaesophagus, gastroesophageal
reflux, paralysis of the swallowing mechanism, and reflux of gastric contents
into the lungs during general anesthesia or vomiting. Chemical pneumonia is
caused by inhaling smoke or ingesting hydrocarbons such as gasoline or
Signs of pneumonia are cough, fever, depression, rapid
breathing, rapid pulse, and occasionally a nasal discharge that is thick
with mucus. The cough is moist and bubbling, indicating fluid in the lungs.
Dogs with severe pneumonia frequently sit with their head extended and elbows
turned out to allow for greater expansion of the chest.
The diagnosis is made by chest X-ray and blood tests. Bacterial culture and
sensitivity tests aid in selecting the most effective antibiotic.
Treatment: Dogs with fever and signs of respiratory infection should receive
urgent veterinary care. Take the dog to the hospital immediately. Do not give
cough suppressants. Coughing is beneficial because
it clears the airway and facilitates breathing.
Bacterial infection responds well to antibiotics selected
specifically for the bacteria causing the disease. Your veterinarian will
select the most appropriate drug. The antibiotic should be continued for at
least three weeks, or until the follow-up chest X-rays show clearing.
Any predisposing causes, such as gastroesophageal reflux or a bronchial
foreign body, should be treated to prevent recurrence.
WebMD Veterinary Reference from "Dog Owner's Home Veterinary Handbook"