A 79-Year-Old Man With Chronic Aspiration and an 18F-Fluorodeoxyglucose-Positron Emission Tomography/Computerized Tomography Positive Lung Mass

CASE PRESENTATION A 79-year-old man with a history of diabetes mellitus presented with a chronic productive cough associated with food intake and unintentional weight loss of 6 pounds in the prior month. He denied fever, chills, night sweats, or pleuritic chest pain. He had smoked 2 packs of cigarettes per day for over 30 years. Physical examination was unremarkable. Chest x-ray showed a right upper lobe pulmonary lesion. Computerized tomography (CT) scan of the chest showed extensive mass-like consolidative changes with associated volume loss in the right upper lobe (Figure 1). Positron emission tomography (PET)-CT scan showed abnormal fluorodeoxyglucose (FDG) uptake in the entire lesion, most marked within the pulmonary apex (Figure 1). The patient underwent bronchoscopy with bronchoalveolar lavage and transbronchial biopsy of the right upper lobe. The right lung biopsy showed organic vegetable matter with associated suppurative inflammation, necrosis, and Gram-positive filamentous bacterial colonies (Figure 2). These organisms stained positive by Gram and silver stain, but were negative by Fite stain. Bronchoalveolar lavage fluid cultures grew Actinomyces graevenitzii, identified by partial 16S ribosomal ribonucleic acid (RNA) gene sequencing. The isolate was susceptible to penicillin and clindamycin. A diagnosis of pulmonary actinomycosis was made based on clinical presentation, histopathology findings, and culture. The patient improved clinically on high-dose, intravenous penicillin therapy. Penicillin was switched to clindamycin after a few days due to the development of a rash. Repeat CT scan of the chest after 8 weeks of antibacterial therapy showed significant improvement in the right upper lobe consolidative process (Figure 3).