Abstract
Background Actinomycosis is an uncommon chronic suppurative bacterial infection caused by anaerobic
bacteria. Pulmonary actinomycosis is even more infrequent and generally simulates
a wide variety of pulmonary disorders including tuberculosis and lung cancer. Therefore
delayed diagnosis and misdiagnosis is common. Here, actinomycosis was initially confused
with pulmonary carcinoma.
Methods We report on three cases of inflammatory tumors caused by pulmonary actinomycosis.
All three patients were male and had a history of alcoholism and poor oral hygiene
associated with dental disease. Clinical symptoms were nonspecific and radiographic
imaging showed tumor-like mass lesions not distinguishable from neoplasms. Preoperative
bronchoscopy, sputum culture, laboratory tests and bronchoalveolar lavage neither
confirmed an infectious disease nor ruled out lung cancer. Hence all patients underwent
thoracotomy for both diagnosis and definitive treatment. Intraoperatively we encountered
a necrotizing infection forming cavitary as well as tumorous lesions and a lobectomy
was performed due to destroyed lung tissue. In one case the tumorous lesion involved
the chest wall so that partial resection of the 3rd rib with the adjacent soft tissue
was mandatory.
Results Histological examination of the pulmonary specimen established the diagnosis of pulmonary
actinomycosis. All patients recovered well and received antibiotic therapy with oral
penicillin.
Conclusions The diagnosis of pulmonary actinomycosis remains challenging. In cases of an inflammatory
tumor imitating lung cancer, surgical resection is mandatory, both to confirm the
diagnosis and for the definitive treatment in cases with irreversible parenchymal
destruction. Here, surgery in combination with medical treatment offered reliably
excellent results.
Key words
pulmonary actinomycosis - cavitary pulmonary disease - lung infection - septic thoracic
surgery - pleural empyema
