CHEST I 103 I 6 I JUNE, 1993 1887 Pulmonary actinomycosis usually occurs as a result of the aspiration of oropharyngeal material in the setting of poor dental hygiene or oral trauma. When pathogenic, it is invasive, often mimicking a malignancy in presentation and macroscopic appearance. Endobronchial disease due to this pathogen rarely is reported. Ariel et al recently described five patients ...