• An infectious process caused by bacteria of the Actinomyces species. It is characterized by the formation of purulent and painful abscesses in the mouth, lungs and gastrointestinal tract.
  NCI
  U.S. National Cancer Institute, 2021
• Infections with bacteria of the genus ACTINOMYCES.
  NLM Medical Subject Headings
  U.S. National Library of Medicine, 2025
• Actinomycosis is a chronic localized or hematogenous anaerobic infection caused by Actinomyces israelii and other species of Actinomyces. Findings are a local abscess with multiple draining sinuses, a tuberculosis-like pneumonitis, and low-grade systemic symptoms. Diagnosis is by the typical appearance plus laboratory identification....
  Merck Manuals
  Merck & Co., Inc., 2025
• Actinomycosis is a subacute-to-chronic bacterial infection caused by filamentous, gram-positive, non�acid-fast, anaerobic-to-microaerophilic bacteria. It is characterized by contiguous spread, suppurative and granulomatous inflammation, and formation of multiple abscesses and sinus tracts that may discharge sulfur granules.
  Medscape
  WebMD, 2025
• Actinomycosis is a bacterial infection that occurs most often in the face and neck. Symptoms of actinomycosis include a neck mass, jaw or face pain, and formation of pockets of pus (abscess). When actinomycosis occurs in other parts of the body, symptoms can include cough, chest or stomach pain, fever, and weight loss. It is usually...
  NIH Genetic and Rare Diseases
  National Center for Advancing Translational Sciences
• Actinomycosis is an infectious disease caused by anaerobic, gram-positive actinomycetes. The most common clinical forms of actinomycosis are cervicofacial and abdominal. In women, pelvic actinomycosis is possible. Many other sites of infection have been described, although less frequently than cervicofacial and abdominal actinomycoses....
  Epocrates
  Athenahealth, Inc., 2019
• Actinomycosis, chronic bacterial infection of humans and cattle that is caused by anaerobic or microaerophilic (oxygen-requiring) species of the genus Actinomyces. The disease is characterized by the development of multiple abscesses (painful, hard, pus-filled swellings) and draining sinus tracts...
  Encyclopedia Britannica
  Encyclopedia Britannica, Inc., 2025