Pulmonary localisation represents only 15% of all cases of actinomycosis. The clinical symptoms and radiological changes of this disease are non-specific and sometimes it can be misdiagnosed, usually as tuberculosis, lung cancer or lung abscess. In the reported case, what might look like the lung cancer, finally turned out to be actinomycosis. The interesting case is presented of lung actinomycosis in a 77-year-old farmer, admitted to the Department of Pneumonology, Oncology and Allegology in Lublin due to a massive haemoptysis. CT scan of the chest showed, apart from other changes, the spicular consolidation in the right lung which aroused oncology vigilance. The diagnostic path, which was a real medical challenge, led to the diagnosis of actinomycosis. The process of diagnosis and consequent treatment, which led to the complete regression of clinical and radiological changes, is presented.
Keywords: actinomycosis; imitator; lung cancer.