Pneumonia is a serious respiratory disease that can affect dogs of any age or breed. It is caused by pathogens or foreign material that enter the lungs through the airways and cause significant inflammation and disease. Symptoms vary depending on the severity of pneumonia but may include difficulty breathing, coughing up mucus or blood, lethargy, fever, loss of appetite and weight loss. If left untreated pneumonia can be fatal so it's essential to recognize the signs early and seek veterinary care immediately. In this article, we'll explore how pneumonia develops in dogs as well as how to diagnose and treat this condition.

What is pneumonia in dogs?

Pneumonia in dogs is a complex condition involving inflammation of the lungs, leading to fluid build-up in the tiny air sacs known as alveoli. There are different types of pneumonia in dogs, with bronchopneumonia being one that originates from infections in the airways, like those in the respiratory tract. In contrast, hematogenous pneumonia arises when pathogens spread through the bloodstream, ultimately affecting the lungs.

What are the causes of pneumonia in dogs?

Pneumonia in dogs can stem from several different causes, including infections from various agents. Other factors that can lead to pneumonia include aspiration – when gastric contents, food, chemicals, or fluids enter the lungs – and inhalation of foreign materials or particles, such as chemicals or smoke.

Pneumonia can be triggered by a wide range of infectious agents, such as bacteria, viruses, fungi, protozoa, and parasites. However, in the case of aspiration or inhalation pneumonia, the initial cause may not be an infectious agent at all. Instead, these types of pneumonia are linked to the presence of foreign materials in the lungs.

While aspiration and inhalation pneumonia may begin as non-infectious, they can still lead to secondary infections as microbial pathogens take advantage of the compromised lung environment.

In summary, the common causes of pneumonia in dogs include:

  • Bacterial pneumonia - Invariably, bacterial pneumonia in dogs originates from their own microflora if their immune system has been weakened for some reason.
  • Viral pneumonia -  Multiple pathogens are known to cause viral pneumonia, including Canine Distemper Virus, Canine Adenovirus-2, Canine Herpesvirus, canine Parainfluenza Virus and canine Influenza virus.
  • Fungal pneumonia - Blastomycosis is the most common fungus known to cause pneumonia in dogs.
  • Aspiration - When a foreign substance enters the airways, such as food or stomach contents, pneumonia can develop.
  • Inhalation - Inhalation of particulates such as gaseous chemicals or smoke into the lower respiratory tract can cause pneumonia.

What are the symptoms of pneumonia in dogs?

Clinical abnormalities associated with pneumonia in dogs can manifest in various ways. Common symptoms may include:

  • Coughing: A persistent cough can be a sign of pneumonia.
  • Wheezing: Difficulty breathing may cause audible wheezing.
  • Nasal discharge: A clear, yellow, or greenish nasal discharge may be present.
  • Lethargy: Affected dogs may appear more tired or less active than usual.
  • Weight loss: Pneumonia can lead to a negative metabolic state and decreased appetite, resulting in weight loss.
  • Tachypnea: Rapid breathing can be observed in dogs with pneumonia.
  • Dyspnea: Labored breathing, particularly during exertion.
  • Weakness: Dogs with pneumonia may exhibit overall weakness.
  • Fever: Elevated body temperature is common in dogs with pneumonia.
  • Dysphagia: Difficulty swallowing can be a symptom of pneumonia.
  • Altered mentation: Changes in behavior or awareness may be observed.
  • Exercise intolerance: Dogs with pneumonia may have difficulty exercising or show reluctance to engage in physical activity.

If your dog exhibits any of these clinical symptoms, consult your veterinarian immediately for a proper diagnosis and treatment plan. Early intervention is crucial for a better chance of recovery and to prevent complications.

How is pneumonia diagnosed in dogs?

Diagnosing pneumonia in dogs involves a combination of clinical examination, evaluation of the dog's medical history, and various diagnostic tests. Veterinarians will typically use the following methods to determine if a dog has pneumonia:

  • Medical history: Clients may report episodes of vomiting, trauma, or general anesthesia in the history. Moreover, some dogs might have recently been exposed to contagious agents while staying at a shelter or boarding facility.
  • Physical examination: A thorough physical exam will help to identify any clinical signs associated with pneumonia. Your veterinarian will use a stethoscope in order to listen for abnormal breathing sounds (such as wheezing or crackles) that may indicate pneumonia.
  • Chest X-rays: Radiographs are used to take images of the lungs, which can then be evaluated for signs of pneumonia such as pneumonia infiltrates, air bronchograms, and pleural effusion.
  • Blood testing: Evaluation of a blood sample may reveal clues associated with pneumonia, such as an elevated white blood cell count.
  • Bronchoalveolar lavage (BAL): A technique used to obtain a sample of secretions from the lower respiratory tract, which can then be examined for signs of pneumonia. Samples from the BAL can then be sent for bacterial culture and sensitivity testing.
normal chest x-ray in a dog
Normal chest X-ray
pneumonia in dogs
X-ray of a dog with pneumonia

What is the treatment for pneumonia in dogs?

Treatment for pneumonia in dogs depends on the severity of the condition and the underlying cause. A tailored treatment plan will be developed by your veterinarian based on the diagnostic findings. Common components of treatment for canine pneumonia may include:

  • Antibiotics: If the pneumonia is caused by a bacterial infection, your veterinarian will prescribe antibiotics. The choice of antibiotic will depend on the results of the culture and sensitivity testing, if available. It is crucial to complete the entire course of antibiotics as prescribed to ensure the infection is fully treated and to prevent antibiotic resistance.
  • Antifungal or antiviral medications: In cases of fungal or viral pneumonia, appropriate antifungal or antiviral medications will be prescribed by your veterinarian.
  • Fluid therapy: When dehydrated, both mucus production and its ability to clear the airways is drastically reduced. This can lead to respiratory issues that make it difficult to breathe properly. Dehydration resulting from pneumonia may be addressed with intravenous or subcutaneous fluid therapy to help maintain hydration and electrolyte balance.
  • Oxygen therapy: Dogs experiencing difficulty breathing or low blood oxygen levels may require oxygen supplementation. This can be provided through oxygen cages, masks, or nasal cannulas.
  • Cough suppressants: If the dog has a persistent, nonproductive cough, your veterinarian may prescribe cough suppressants to provide relief. However, cough suppressants should be used with caution and only under a veterinarian's guidance, as they may not be appropriate in all cases.
  • Bronchodilators: These medications can help open up the airways and ease breathing in dogs with pneumonia.
  • Nebulization and coupage: Nebulization involves using a machine that produces a fine mist of medication or saline, which the dog inhales to help break up mucus in the airways. Coupage is a technique where the chest is gently percussed to help loosen secretions and stimulate coughing, which can help clear the airways.

It is crucial to follow your veterinarian's recommendations for treating pneumonia in your dog. Early intervention and adherence to the prescribed treatment plan can significantly improve your dog's chances of a full recovery.

What is the prognosis for dogs with pneumonia?

The prognosis for pneumonia in dogs depends on the severity of the condition and the underlying cause. With an early diagnosis and prompt treatment, most dogs (70-90%) will make a full recovery from pneumonia. However, pneumonia can lead to serious complications if left untreated or if treatment is not successful. Some cases may even be fatal. Prompt veterinary care is essential for ensuring the best prognosis for your dog. Recurring pneumonia appears to be a negative prognostic indicator in dogs with a recent study revealing only 2/11 dogs were alive at the 1-year mark.

If pneumonia is suspected in your dog, it is important to contact your veterinarian right away for an accurate diagnosis and appropriate treatment plan. Early intervention can make all the difference when it comes to ensuring a successful recovery. With proper care, most dogs with pneumonia will make a full recovery.

FAQs

Is pneumonia in dogs contagious?

Pneumonia in dogs can be contagious, depending on the underlying cause. If pneumonia is caused by infectious agents, such as bacteria, viruses, or fungi, it can be contagious to other dogs.

What is the recovery time for dogs with pneumonia?

The recovery time for dogs with pneumonia can vary depending on the severity of the condition, the underlying cause, and the dog's overall health. For mild cases of pneumonia, where the dog is stable and treated on an outpatient basis, the recovery time may be shorter, potentially ranging from many weeks. However, more severely affected dogs that require hospitalization and frequent monitoring may take longer to recover fully.

It is generally recommended to re-evaluate the dog's physical, hematological, and radiographic parameters 10-14 days after starting therapy to assess their progress. Some veterinarians may suggest continuing treatment for at least a week after the resolution of radiographic signs of pneumonia to ensure a complete recovery. In some cases, the recovery process may take several weeks to a few months, especially if there are complications or pre-existing health conditions.

What is the treatment for aspiration pneumonia in dogs?

As aspiration pneumonia is typically contaminated with microbes, treatment for aspiration pneumonia in dogs typically involves a combination of supportive care and antibiotics.

In conclusion, pneumonia in dogs is a serious condition that requires prompt attention and proper treatment. The prognosis for recovery can be favorable, particularly when the condition is diagnosed early, and appropriate therapy is initiated. Recovery times may vary, but with patience, diligence, and adherence to the prescribed treatment plan, many dogs can make a full recovery and return to their normal, healthy lives. Remember that maintaining your dog's overall health, including keeping them up-to-date with vaccinations, can help protect them from contagious respiratory diseases and contribute to their long-term well-being. Thanks for reading and if you have any questions, please contact your veterinarian.