Pulmonary Actinomycosis Revealed by a Solitary Pulmonary Nodule

Background. Pulmonary actinomycosis (PA) is a rare and ubiquitous bacterial disorder, combining subacute or chronic focal suppuration and an expansive fibrogranulomatous lesion. Lung involvement is rare. The radioclinical manifestations of this infection are polymorphic and confusing. The form revealed by a solitary pulmonary nodule is exceptional and not documented in the literature. Case Presentation. We report a case of a 71-year-old patient, 25-year package smoker, revealed by repeated moderate-abundance hemoptysis with a rare radiological image: in the form of a solitary pulmonary nodule located at the left chest base. The negativity of bacteriological research, endoscopic samples, the failure of treatment of the bleeding by medical and embolization, and at last the suspicion of a neoplasia led us to perform a thoracotomy for diagnostic and therapeutic purposes. This surgery highlighted evidence of filamentous basophilic grains posing the diagnosis of PA. Appropriate treatment allowed a cure without recurrence after 02 years of follow-up. Conclusion. Pulmonary actinomycosis can be revealed by different radiological forms. Pulmonary actinomycosis should be considered in the presence of any solitary lung nodule in order to reduce the morbidity and cost associated with thoracotomy.