All dogs have lungs and these important parts of the lower respiratory tract can develop a variety of problems, including pneumonia. Just like people, pneumonia can make it difficult for a dog to breathe and can even be life threatening. By better understanding this problem and being able to recognize some of the signs and symptoms of this disease, pet owners can be more prepared to care for a pet with pneumonia.
What is Pneumonia?
Pneumonia is a disease that affects the lungs. Inflammation inside the microscopic parts of the lungs called air sacs causes swelling, pus, and fluid that makes it difficult for a dog to breathe. Lungs are not normally filled with fluid or pus so when they are there is less room for air to fill these balloon-like structures in the chest.
Signs of Pneumonia in Dogs
- Short, shallow breaths
- Yellow, green or bloody mucus from the nose or after a cough
- Difficulty breathing
- Blue, grey, or purple mucus membranes
- Loss of appetite
The signs of pneumonia in dogs are often the same as in people. Anytime the lower respiratory tract is compromised there may be difficulty breathing. This is most easily recognized with short and shallow breaths that can turn into hyperventilation and coughing which may produce mucus. This mucoid discharge is typically green, yellow, or even bloody when there is an infection and an infection is quite common with pneumonia. Colored mucus can be seen coming from the nose as well as after a productive cough. A rectal body temperature over the normal 101-102.5 degrees is indicative of a fever, which is also usually seen in a dog with pneumonia, due to the secondary infection inside the lungs.
Since the lungs aren't able to work efficiently in a dog with pneumonia, oxygen isn't being moved throughout the body very well. Blue, grey, or purple tinged mucus membranes may be seen if oxygenation is extremely poor along with lethargy and fatigue. In addition to the other symptoms, a dog with pneumonia also can't smell its food and simply doesn't feel well so it often doesn't eat much, if at all.
Causes of Pneumonia in Dogs
Pneumonia can be caused by an irritation, injury, or more commonly an infection of the lungs. Some examples of these causes include:
- Inhaled irritants: Aerosol sprays, smoke, air pollutants, and other inhaled irritants may cause inflammation in the lungs and result in pneumonia. Pets who live in homes where their owners smoke are more likely to develop lung issues just like their human counterparts.
- Aspiration: Aspiration is when food or other liquid or solid material is accidentally inhaled into the lungs. This can be seen in a dog that has been vomiting. It is also a potential complication associated with anesthesia.
- Diseases: Many diseases can affect the dog's immune system or compromise it's respiratory tract including megaesophagus, cleft palate, cancer, laryngeal paralysis, and others. These diseases can make a dog more likely to develop a bacterial infection in the lungs which causes pneumonia.
- Viruses: Secondary bacterial infections and inflammation due to viral infections such as parainfluenza, canine adenovirus type-2, and canine flu may occur in a dog and cause pneumonia. These viral infections are often easily spread from dog to dog.
- Bacteria: The most common cause of pneumonia, bacteria such as Escherichia coli, Pseudomonas aeruginosa, Bordetella bronchiseptica, Streptococcus zooepidemicus, Pasteurella multocida, Klebsiella pneumoniae, and different Mycoplasma species often lead to infections that result in pneumonia. These bacteria may even spread from dog to dog.
- Trauma: If an injury to the chest occurs, a dog may develop inflammation in the lungs. Pneumonia can result from being hit by a car, falling off a balcony, or any other chest injury.
Diagnosing Pneumonia in Dogs
A veterinarian will perform a full physical examination on a dog after an owner notes symptoms that are characteristic of pneumonia. The vet will look for nasal discharge, coughing, take the temperature of the dog, and listen to the lungs using a stethoscope. If pneumonia is suspected X-rays of the lungs will need to be taken to look for fluid and inflammation. Sometimes a bronchial lavage is also performed in order to check if bacteria is present in the lungs. A sample of the nasal discharge or lung fluid from the lavage may be sent out for a microbial culture or cytology to see what type of bacteria is causing the pneumonia. Finally, bloodwork is often checked to see if an infection is systemic by looking for an elevation in the white blood cell count.
Treatment of Pneumonia in Dogs
Pneumonia is typically treated in a veterinary hospital in order to monitor a dog's breathing and administer medications. Pneumonia can be life threatening so this is a serious condition. Medications including antibiotics, anti-inflammatories, antitussives, expectorants, bronchodilators, and sometimes even steroids may be used to manage the symptoms of pneumonia. Coupage may be performed in order to break up mucus inside the lungs, humidifiers or nebulizers may be used to loosen the mucus, and brief exercise sessions may be needed to encourage a dog to cough up the mucus.
Dog's with pneumonia will often not want to eat, but good nutrition is important in helping them recover. Techniques such as warming up the food and offering extra smelly canned or baby foods may be used to entice a pet to eat. There are also medications to stimulate their appetite. In severe cases, a feeding tube may need to be placed. IV fluids are also often needed to prevent dehydration as well as administer medications. Finally, if oxygen levels are low, supplemental oxygen may also be needed to help a dog with pneumonia get enough oxygen circulating in its body.
How to Prevent Pneumonia in Dogs
The best way to prevent a dog from developing bacterial or viral pneumonia is to vaccinate it for these diseases. The most common causes of pneumonia have vaccines available for them but keeping a dog out of a known infected area is also of course recommended. Places where dogs frequent, including dog parks, dog daycare, and boarding facilities can all harbor bacteria and viruses that can cause pneumonia. If a dog is coughing or showing signs of pneumonia or another respiratory disease, other dogs should be kept away from it as well.
If inhaled irritants are the concern, keeping the air clean where a dog lives can decrease the likelihood of it causing pneumonia. Air purifiers can help keep home air clean, pet owners should never smoke in the house or by their pets, and aerosol sprays should be avoided.
Is Pneumonia Contagious?
If the pneumonia a dog has is caused by a virus or bacteria then yes, it can be contagious. If pneumonia is caused by aspiration, an irritant or trauma and inflammation is present without an infection then it is not contagious but there is always concern for an infection developing. To be safe, if a dog is diagnosed with pneumonia it is best to keep it isolated and away from other pets.