Pneumonia (Fungal) in Dogs

Your dog may ingest one of the fungi that cause fungal pneumonia by breathing in the spores from the soil where they live. It is impossible to see or smell these fungi so there is no way for you to know where or how your dog got the infection. Although sometimes the infection comes on suddenly, it is much more common for it to slowly progress from a minor cough or runny nose into full blown respiratory distress over a period of months. The main symptom of fungal pneumonia is coughing and noisy breathing, so if you notice that your dog has a cough or is having trouble breathing you should take a trip to the veterinarian just in case. Some dog owners may try to treat fungal pneumonia at home with antibiotics available to the public, but fungal pneumonia does not respond to antibiotics and that can make the infection worse. It is always best to get treatment from a professional rather than home remedies because some illnesses, such as fungal pneumonia, can be life threatening if treatment is not started right away. As with most illnesses, the earlier you start treatment, the better the chances of a successful recovery.

Fungal pneumonia, also called mycotic pneumonia, refers to a fungal infection of the lungs that results in pneumonia caused by breathing in one of many different fungi spores. The fungi will travel through the dog’s circulatory system and lymph nodes, causing severe coughing, breathing trouble, and a viscous phlegm in the nose and throat. Most of the fungi that cause fungal pneumonia is in the soil and is not usually contagious from one dog to another. This is a serious disorder that can become a life-threatening emergency quickly if not treated right away so treatment from a veterinarian or animal hospital is critical to the health of the dog.

The symptoms of fungal pneumonia will vary depending on the type of fungi spores that your dog is infected with and the length of time your dog has had the infection. The most common signs of fungal pneumonia are:

• Diarrhea (sometimes tinged with blood)
• Appetite loss
• Losing weight
• High temperature
• Discharge from eyes and nose
• Coughing
• Breathing difficulty
• Loss of sight (i.e. squinting, bumping into things)
• Depression
• Raised rash on the skin
• Loud breathing
• Weakness
• Inability to walk
• Fainting

Although any breed or sex of dog can get fungal pneumonia, it is most common in male sporting and hunting dogs, such as the:

• Pointers
• Retrievers
• Setters
• Spaniels
• Vizslas
• Weimaraners

There are many fungi that can cause fungal pneumonia, but the most common ones are:

• Cryptococcus
• Histoplasma
• Coccidioidomycosis
• Candida
• Blastomyces
• Aspergillus

A complete physical examination will be done by your veterinarian including weight, body temperature, heart rate, and blood pressure. The veterinarian will listen to your dog’s lungs and check his eyes, nose, throat, and ears. It is best to provide the veterinarian with as much of your dog’s medical history as you know including vaccinations, previous illnesses or injuries, changes in behavior, what symptoms you have noticed, and when they started. Some medical tests need to be done to rule out other illnesses, such as cancer or a bacterial infection. These tests include checking your dog’s blood count for white cell count, a tracheal wash to get a sample of fluid and pus, urinalysis, and a fine needle aspiration of any nodules or lesions. The veterinarian will also need to get x-rays of your dog’s chest to see how far the infection has spread. An ultrasound and CT scan may also be necessary.

If your dog is in respiratory distress, the veterinarian will most likely give IV fluid and oxygen therapy. This will need to be done in the hospital, and they may decide to keep your dog overnight for observation. Antifungal medication (i.e. fluconazole, ketoconazole, Itraconazole) is the only treatment for fungal pneumonia. It can be a long and expensive process because it may take several types of medication before finding the one that works on your dog.

Although the treatment can be very costly and may last for up to six months, it is best to keep trying until you find the right type of medication that works. The veterinarian will want to get lab work on your dog while taking the medication because it can be hard on your dog’s liver and kidneys. You will also need to get more radiographs of the chest to be sure the pneumonia is clearing up. Restricted activity may be necessary in some cases until your dog is well enough to walk around without coughing or collapse. Be sure to use all of the medication as prescribed. Do not stop giving your dog the medication because he is “better” because the infection may return and be harder to get rid of. Call your veterinarian if you have any questions or concerns.