title: Actinomyces meyeri presenting as an asymptomatic lung mass.
abstract: A 55-year-old man was admitted to the hospital for an elective herniorrhaphy. A significant past history of smoking and alcohol abuse was noted. The patient had no other complaints but a routine chest X-ray revealed an isolated left upper lobe mass. Laboratory tests were unrevealing and the impression was that the patient had a carcinoma. The surgical specimen consisted of a lobular mass containing multiple microabscesses. Grains consistent with actinomycosis were seen and the culture grew out Actinomyces meyeri. There was no other evidence of disease.
mesh_terms: D000196:Actinomycosis / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery; D003937:Diagnosis, Differential; D006801:Humans; D008169:Lung Abscess / Q000175:diagnosis; D008171:Lung Diseases / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery; D008175:Lung Neoplasms / Q000175:diagnosis; D008297:Male; D008875:Middle Aged