Actinomycosis Diagnosed by Transthoracic Needle Aspiration That Imitate Malignancy

Diagnosis of pulmonary actinomycosis is still an important problem for clinicians. Since clinically it is similar to other infectious and malignant diseases, the majority of patients are diagnosed after the surgical procedure. Fifty five years old male patient was referred to our clinic with the prediagnosis of malignancy. The patient's chest X-ray revealed increased nonhomogeneous density in the left hemithorax unresponsive to antibiotic treatment. In his thoracic computed tomography (CT) a consolidation area with cavitation was observed in the lingular segment. The consolidation area was was in the form of a triangle extending from the hilum to the periphery, with a large base area placed on the pleural surface. The diagnosis could not be obtained by fiberoptic bronchoscopy. With CT-guided transthoracic needle aspiration, diagnosis of pulmonary actinomycosis was obtained histopathologically. Here, we are presenting this case to remind the clinicians that pulmonary actinomycosis should also be considered in the differential diagnosis of pulmonary malignancy.