The Actinomyces culture test is used to detect the presence of Actinomyces species—anaerobic bacteria that can cause chronic infections, especially in the face, neck, chest, or abdomen. Although these bacteria are part of the normal flora of the mouth and gastrointestinal tract, they can cause disease when they invade deeper tissues. The test involves culturing a specimen to isolate the organism and confirm infection. While serum is not a typical sample type (pus, tissue, or drainage are preferred), it may be used in some cases for supportive diagnosis.