Thoracic actinomycosis: CT findings

Radiology. 1998 Oct;209(1):229-33. doi: 10.1148/radiology.209.1.9769836.

Abstract

Purpose: To characterize computed tomographic (CT) findings of thoracic actinomycosis.

Materials and methods: Chest CT scans and radiographs obtained in 22 patients with histopathologically proved thoracic actinomycosis were retrospectively reviewed. All patients were immunocompetent; they were aged 12-73 years (mean, 42.6 years; 14 male, eight female). CT findings were correlated with histopathologic findings in nine patients who underwent surgery (lobectomy [n = 8] or segmental resection [n = 1]).

Results: All of the lesions were unilateral, with an average diameter of 6.5 cm (range, 2-12 cm). Patchy air-space consolidation (n = 20) or a mass (n = 2) was seen on CT scans. Fifteen (75%) of the 20 patients with air-space consolidation had central areas of low attenuation (5-30 mm in diameter) within the consolidation. Thirteen of the 15 patients underwent contrast medium-enhanced CT. Ten (77%) of the 13 patients showed ring-like rim enhancement. Adjacent pleural thickening was seen in 16 patients (73%). At histopathologic examination, central low-attenuation areas at CT were seen as microabscesses with sulfur granules or a dilated bronchus that contained inflammatory cells and Actinomyces colonies. Peripheral enhancement of the low-attenuation areas was wall of the microabscess or surrounding parenchyma composed of granulation tissue rich in vascularity.

Conclusion: Findings of chronic segmental air-space consolidation that contained low-attenuation areas with peripheral enhancement or adjacent pleural thickening at CT were suggestive of thoracic actinomycosis.

MeSH terms

  • Actinomycosis / diagnostic imaging*
  • Actinomycosis / pathology
  • Actinomycosis / surgery
  • Adolescent
  • Adult
  • Aged
  • Biopsy
  • Child
  • Chronic Disease
  • Female
  • Humans
  • Lung / diagnostic imaging
  • Lung / pathology
  • Male
  • Middle Aged
  • Pneumonectomy
  • Radiography, Thoracic
  • Retrospective Studies
  • Thoracic Diseases / diagnostic imaging*
  • Thoracic Diseases / pathology
  • Thoracic Diseases / surgery
  • Tomography, X-Ray Computed*