Fungal Infection (Pneumocystis) of the Lung in Dogs

A weakened immune system can be one cause of pneumocystis carinii in dogs. This fungal infection occurs in the lungs of dogs and can be fatal if not treated early. The fungus comes from the environment and tends to attack dogs that have a lower than normal immune system. This is because with a weakened immune system, the fungus P. Carinii is able to multiply rapidly. This disease is breed-specific and is first noticed with a wheezing cough or labored breathing, and at first glance, you or the veterinarian may feel that the dog has pneumonia. Much detailed and diagnostic testing will need to be done to diagnose a fungal infection of the lung in dogs.

Fungal infection of the lung in dogs, or pneumocystis, is a respiratory infection caused by an atypical fungus called pneumocystis carinii. It can affect dogs with below normal immune systems.

The main symptom of a fungal infection (pneumocystis) of the lung in your dog will be the difficulty in breathing, and this will worsen over a month-long period of time. Other symptoms can include:

• Coughing
• Diarrhea
• Vomiting
• Lack of appetite
• Weight loss
• Unwillingness to exercise
• Heavy, labored breathing

Types

There are specific types that can get pneumocystis more so than others. These are not the only breeds that can get a fungal lung infection, but there is a breed disposition for this disease. Types of breeds can include:

• Cavalier King Charles Spaniel
• Yorkshire Terrier
• Miniature Dachshund
• Dogs that are deficient in immunoglobulin
• Dogs with distemper
• Dogs with demodicosis

This disease does occur in certain breeds due to the fact that they are more susceptible to having an abnormal and weaker immune system, which raises the risk for the fungus P. Carinii to affect the lungs. Therefore, specific causes of fungal infection (pneumocystis) of the lung in dogs are:

• Immune system deficiency
• P. Carinii fungus

If your dog is having trouble breathing or has been coughing for quite some time, it is important to make an appointment with your veterinarian. He will ask you different questions about his symptoms and review his health history. At first, he may want to rule out different diseases, so he will perform tests to check for canine distemper, heartworm, pneumonia, and pulmonary interstitial fibrosis. These diseases have similar symptoms to the fungal infection of P. Carinii.

The veterinarian will perform a lung auscultation, radiography, bronchograms, and peribronchial density testing. He will also do blood work, a urinalysis, biochemistry profile, serological testing, and any other tests to come to the conclusion of this specific disease.

Tests that will give the veterinarian a clear diagnosis are a bronchotracheal lavage and a biopsy of specific specimens of the lung.  Other testing may be performed, depending on if they are available or if  your veterinarian still needs a more definitive means of diagnosing this disease.

There are several modes of treatment for your dog if he has a lung infection due to the fungus pneumocystis carinii. Treatment can include:

Hospitalization

If your dog’s case is severe, hospitalization will be required. Your dog may have to be treated in the intensive care unit to ensure the best and most aggressive treatment. He will need to be kept alone to prevent other pathogens from infecting him.

Oxygen Therapy

Oxygen will be given to your dog if needed to keep his blood oxygen levels within normal range and to keep your dog comfortable.

Antibiotics

Antibiotics will be given for the infection in the lungs. They will need to be continued even if the dog goes home from the hospital.

Physical Therapy

Physical therapy may be recommended to help with the removal of any discharge or substance from the lungs.

Your dog’s recovery depends on his condition. Every dog is different and will respond differently to the treatment in which he has received. Your veterinarian will tell you the prognosis of your dog; if the disease was caught early then his prognosis may be good.

Keep your dog comfortable and be sure to not allow him to jump, run, or play roughly. His lungs will need time to heal.  Be sure to continue any medication prescribed by your veterinarian. When you are not at home to watch him, keep him in a crate or kennel so he doesn’t do anything to jeopardize his treatment and recovery. You will have regularly scheduled visits to your veterinarian so his vitals can be monitored and so the veterinarian can keep a close watch over his condition. He will tell you what to watch for in terms of behavior, and which behavior should cause a need for a phone call to him.