Actinomycosis is a long-term (chronic) bacterial infection that commonly affects the face and neck.
Actinomycosis is usually caused by bacterium called Actinomyces israelii. This is a common and organism found in the nose and throat. It normally does not cause disease.
Because of the bacteria's normal location in the nose and throat, actinomycosis most commonly affects the face and neck. The infection can sometimes occur in the chest (pulmonary actinomycosis), abdomen, pelvis, or other areas of the body. The infection is not contagious. This means it does not spread to other persons.
Symptoms occur when the bacteria enter the tissues of the face after trauma, surgery, or infection. Common triggers include dental abscess or oral surgery. The infection can also affect certain women who have had an intrauterine device (IUD) to prevent pregnancy.
Once in the tissue, the bacteria causes an abscess, producing a hard, red to reddish-purple lump, often on the jaw, from which comes the condition's common name, "lumpy jaw."
Eventually, the abscess breaks through the skin surface to produce a draining sinus tract.
Draining sores in the skin, especially on the chest wall from lung infection with Actinomyces
Minimal or no pain
Swelling or a hard, red to reddish-purple lump on the face or upper neck
Exams and Tests
The health care provider will perform a physical exam and ask questions about your symptoms.
Tests that may be done to check for presence of the bacteria include:
Culture of the tissue or fluid
Examination of drained fluid under a microscope
Treatment of actinomycosis usually requires antibiotics for several months to a year. Surgical drainage or removal of the affected area (lesion) may be needed. If the condition is related to an IUD, the device must be removed.
Full recovery can be expected with treatment.
In rare cases, meningitis can develop from actinomycosis.
When to Contact a Medical Professional
Call your health care provider if you develop symptoms of this infection. Beginning treatment promptly helps quicken the recovery.
Good oral hygiene and regular dentist visits may help prevent some forms of actinomycosis.
Russo TA. Agents of actinomycosis. In: Mandell GL, Bennett JE, Dolin R, eds. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases. 7th ed. Philadelphia, Pa: Elsevier Churchill Livingstone; 2009:chap 255.
Jatin M. Vyas, MD, PhD, Assistant Professor in Medicine, Harvard Medical School; Assistant in Medicine, Division of Infectious Disease, Department of Medicine, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Bethanne Black, and the A.D.A.M. Editorial team.