Discussion
Diagnosis With Brief Discussion
- Diagnosis
- Endobronchial Actinomycosis Associated with Broncholithiasis
- Radiologic Findings
- Chest CT shows calcified material suggesting broncholith in the lateral segmental bronchus of right middle lobe. Associated parenchymal infiltration suggesting subsegmental atelectasis or organizing pneumonia is also seen in lateral segment of right middle lobe.
- Brief Review
- Thoracic actinomycosis is a chronic suppurative pulmonary or endobronchial infection caused by Actinomyces species, most frequently Actinomyces israelii, a gram-positive anaerobic saprophytic organism in the oral cavity that historically was thought to be fungus, but now is considered to be a branching filamentous bacterium.
Rare cases of predominantly endobronchial actinomycosis have been reported including an article on endobronchial actinomycosis associated with broncholithiasis and a case report on endobronchial actinomycosis associated with a foreign body. Endobronchial actinomycosis associated with broncholithiasis likely results from secondary colonization of a preexisting endobronchial broncholith by aspirated Actinomyces organisms. The subsequent inflammatory process results in progressive airway obstruction with distal postobstructive pneumonia of the involved pulmonary lobe or segment.
The CT feature of endobronchial actinomycosis associated with broncholithiasis is a proximal endobronchial calcified nodule (broncholith) associated with distal postobstructive pneumonic consolidation of the involved lobe or segment. Distal postobstructive pneumonic consolidation shows a central low-attenuation area with or without cavities. Mediastinal or hilar lymph nodes are enlarged frequently. Most cases show evidence of an earlier tuberculous infection (e.g., calcified hilar and mediastinal lymph nodes or calcified granulomata). In areas where tuberculosis is endemic, the possibility of endobronchial actinomycosis should be suggested when findings of broncholithiasis are present on CT.
- References
- 1. Kim TS, Han J, Koh W-J, et al. Thoracic actinomycosis: CT Features with histopathologic correlation. AJR 2006; 186:225-231
2. Suzuki JB, Delisle AL. Pulmonary actinomycosis of periodontal origin. J Periodontol 1984;55 : 581-584
3. Chouabe S, Perdu D, Deslee G, Milosevic D, Marque E, Lebargy F. Endobronchial actinomycosis associated with foreign body: four cases and a review of the literature. Chest 2002;121 : 2069-2072
4. Hirschfield LS, Graver LM, Isenberg HD. Broncholithiasis due to Histoplasma capsulatum subsequently infected by actinomycetes. Chest 1989; 96:218 -219
5. Kim TS, Han J, Koh W-J, et al. Endobronchial actinomycosis associated with broncholithiasis: CT findings in nine patients. AJR 2005; 185:347 -353
6. Lee SH, Shim JJ, Kang EY, et al. Endobronchial actinomycosis simulating endobronchial tuberculosis: a case report. J Korean Med Sci 1999; 14:315 -318
- Keywords
- Airway, Infection, Bacterial infection ,