Actinomycosis and Nocardiosis in dogs

These bacterial skin infections, acquired by contact with infected soil, generally occur in hunting dogs. Both types of bacteria can produce a systemic infection that involves the lymph nodes, brain, chest cavity, lungs, and bones.

Subcutaneous abscesses with draining sinus tracts appear at the site of a puncture wound or break in the skin, usually in the head and neck area. The wound discharge often resembles tomato soup and/or contains material that looks like sulfa granules. Norcardiosis can be associated with gingivitis and mouth ulcers.

Treatment: The diagnosis is made by culturing the wound drainage. Treatment involves surgically opening infected abscesses and draining body cavities. Norcardiosis responds to sulfa drugs; actinomycosis to penicillin. Prolonged antibiotic treatment is necessary. If the infection has spread deeper than the skin, the dog may not survive.