Section: Veterinary Care In-depth
Diagnosis In-depth
Certain diagnostic tests must be performed to confirm the diagnosis of blastomycosis and exclude other diseases that may cause similar symptoms. Tests may include:
A complete medical history and physical examination, including auscultation (listening with a stethoscope) of the lungs, careful examination of the eyes and nervous system, and evaluation of the skin for draining nodules
A complete blood count (CBC or hemogram) to evaluate the severity and chronicity of inflammation, detect the presence of non-regenerative anemia, and check platelet count. The clinical presentation of animals with some diseases associated with low platelet count (Ehrlichiosis, Rocky Mountain spotted fever) can resemble blastomycosis.
Serum biochemistry tests to determine the effect of blastomycosis on other organ systems, and to evaluate the health of other organ systems, especially the liver and kidneys, before treatment with anti-fungal drugs that can be toxic for the liver and kidneys. Rarely, high blood calcium concentration (hypercalcemia) is found in animals with systemic fungal infection and hypercalcemia can occur in diseases that can be confused with systemic fungal infection like lymphosarcoma. Certain blood proteins may be increased in the blood of animals with systemic fungal infection and in those with other chronic infectious diseases.
Urinalysis to identify urogential involvement, evaluate kidney function and check for bacterial urinary tract infection.
X-rays of the chest to evaluate the severity of lung involvement and to check for enlarged lymph nodes in the chest. Bone involvement also may be identified on X-rays of the chest.
X-rays of the abdomen to evaluate vital organs, especially the liver and kidneys. Bone involvement also may be identified on X-rays of the abdomen.
Serologic tests for heartworm disease, brucellosis, and rickettsial infection as well as the agar gel immunodiffusion test to identify blastomycosis. The agar gel test is very reliable but may be negative early in the course of infection.
Finding the blastomyces organism during microscopic examination of material collected from draining skin nodules results in a definitive diagnosis.
Microscopic examination of a biopsy specimen from affected tissue by a veterinary pathologist can also lead to a definitive diagnosis, but this method is more invasive, and results take longer to return from the laboratory.
Related Articles
-
1
Cryptococcosis in Dogs
Cryptococcosis is a fungal disease contracted by inhalation of spores, which may affect dogs, cats and people. The excrement of birds, especially pigeons, is the main environmental reservoir for the spores,...
» Read More
-
2
Chronic Coughing in Dogs
Coughing, a common protective reflex that clears secretions or foreign matter from the throat, voice box, windpipe or airways, and protects the lungs from aspiration, affects the respiratory system by...
» Read More