Canine Blastomycosis Symptoms Diagnosis

Canine Blastomycosis is a fungal disease that affects the entire body and is often misdiagnosed as cancer, viral infections, Lyme disease and other fungal infections. Unfortunately, time wasted with improper diagnosis can result in loss of vision or death, and, even if correctly diagnosed, relapse is a concern. With advances in antifungal medication, however, treatment is becoming more effective and affordable once a proper diagnosis is made. Young dogs that have access to outdoor areas are at increased risk for contracting blastomycosis, but any dog can contract the disease.

Features

Blastomycosis is caused by a parasitic fungus called Blastomyces dermatidis. This mold grows in moist soil or decaying vegetation and can be inhaled by humans and dogs. It is considered to be more common in working dogs such as coonhounds, pointers and weimaraners, but this is because they often hunt in areas where the mold is prevalent. There is no way to remove Blastomyces dermatidis from the environment, but be aware of areas with decaying organic material, recently disturbed soil, rotting vegetation, bird droppings or landscape projects, especially where Blastomyces dermatidis is present in the midwest, south and Canada.

Symptoms

After inhaling the spores, your dog may not show symptoms for days or weeks during incubation as the spores settle in the airways and begin to reproduce. Since Blastomycosis can imitate a range of other diseases, the symptoms appear generic, even though the illness is quite serious. Symptoms include fever, lethargy, anorexia, vomiting, persistent cough, pneumonia, ocular infection or sudden blindness, depression, twitches, loss of coordination, stumbling gait, skin ulcerations, lumps and lymph node swelling, weight loss, hair loss, lameness or bloody urine.

Diagnosis

Diagnosis is based on clinical signs and laboratory tests, which are often not definitive. The two most effective lab tests are cytology, the microscopic study of cells obtained from fluid from an open wound or aspirated from a lymph node, and histopathology, taken from a tissue sample. A blood test can determine exposure but doesn't indicate a diagnosis.

Treatment

Treatment has evolved significantly in the past few years, though it is still not a guarantee of recovery. Amphotericin-B, which had to be given intravenously to protect the kidneys, was once the only known medication to treat Blastomycosis. Since then, oral azoles such as Itraconazole (Sporanox), Ketoconazole (Nizoral) and Fluconazole (Diflucan) have proven effective when used for three to six months, depending on severity.

Recovery

During the first few days or weeks of treatment, large numbers of fungi in the lungs die, causing severe illness and lung inflammation, which can be treated by Prednisone. This may cause your dog to become anorexic, so it is important to force your dog to eat and drink. A high-calorie diet is important so adding chicken, stewed meats, peanut butter, cheese, Pedialyte, eggs or yogurt to meals can provide an enticement to eat as well as improve overall health.

References

• Dog Health
• Allergic Pet
• Veterinary Medicine