Abstract
The diagnosis of thoracopulmonary actinomycosis is challenging because it is a rare disease, symptoms are aspecific and can mimic a lot of other lung pathologies. Especially the differential diagnosis with pulmonary tuberculosis is difficult because clinical symptoms are often very similar. We present a case of thoracopulmonary abcedating actinomycosis in a young immunocompetent man with no predisposing illness. He was initially treated for pulmonary tuberculosis. He showed good response to IV penicillin, which was later switched to oral amoxicillin when he went home.