Blast mycosis: A fungal disease that often results from inhaling the fungus into the respiratory system. Once the spores are inhaled, they begin to grow in the small airways of the lungs. Later on, the fungus spreads throughout the body and may infect many body organs. The usual source of infection is the soil and is most commonly found in the warm, moist environments of the Ohio and Mississippi River valleys and the Southeastern U.S. There is no treatment of the soil to rid the fungus from the area. Common signs of Blastomycosis include fever, depression, weight loss, and loss of appetite. Many cases have draining skin wounds. Coughing and other signs of respiratory infection may or may not occur. Blindness can result from the infection when the eyes are infected. Other signs may include lameness, seizures, enlarged lymph nodes, and testicular inflammation.
DIAGNOSIS:
Requires laboratory microscopic examination of fluids and/or tissues. If draining skin lesions are present, the diagnosis can often be made in the office during the initial visit by examination of the wound exudate. Chest X-rays are also useful in diagnosis. A blood test is also available to determine potential exposure. A diagnosis by this method may require a repeated test 3-4 weeks after the initial test.
TREATMENT:
Available but not always successful if the pet is not presented for treatment until the later stages of the disease. Treatment of this disease may require months of therapy and is quite expensive. There is no way to accurately determine if treatment will be successful. The first 24-72 hours after treatment is begun is the most critical. Death may occur from respiratory distress caused by the inflammation resulting from large numbers of the organism dying when treatment is begun.
Relapses are more common when the disease affects the nervous system and/or the eyes. Castration may be required in male dogs to remove a potential source of re-infection. Treatment of infected eyes usually is surgical removal, again to remove a major source of re-infection of the rest of the body.
HUMAN RISK:
The disease is not thought to be infectious to other animals or people once it is in the pets body. Therefore isolation of the pet is not necessary. The true risk for other pets & people comes from sharing the same environment (allowing contact with the same soil). We recommend your personal physician be notified once Blastomycosis has been diagnosed in your pet for his/her human health recommendations. Humans falling into the category of having known immunosuppression would be the most vulnerable to the disease. This group might include infants, small children, transplant patients, chemotherapy patients, elderly family members, and HIV/AIDS positive people. Strict hygiene should be followed when handling pets with draining skin wounds. Thorough hand washing is recommended after handling the pet.
