title: Nontuberculous mycobacterial pulmonary infection in immunocompetent patients: comparison of thin-section CT and histopathologic findings.
abstract: OBJECTIVE
  To identify and describe the thin-section computed tomographic (CT) findings of nontuberculous mycobacterial (NTM) pulmonary infection in immunocompetent patients and to compare these findings with histopathologic findings.
  
  
  METHODS
  Between April 2002 and March 2003, the thin-section chest CT findings in and histopathologic lung tissue specimens from 22 patients who fulfilled the American Thoracic Society diagnostic criteria for NTM pulmonary infection were retrospectively reviewed. The lung lesion patterns (ie, small nodules, branching centrilobular nodules [ie, tree-in-bud pattern], consolidation, cavities, bronchiectasis, and volume loss) seen at CT at the sites of transbronchial lung biopsy (n = 22) or lobectomy (n = 1) were compared with the histopathologic findings.
  
  
  RESULTS
  Thirteen of the 22 patients were found to have Mycobacterium abscessus pulmonary infection; seven, to have Mycobacterium avium-intracellulare complex infection; and two, to have Mycobacterium fortuitum infection. Regardless of the specific infective mycobacterial species, bilateral small nodules (in 22 [100%] lung locations), cylindric bronchiectasis (in 20 [91%] locations), and branching centrilobular nodular lesions (in 17 [77%] locations) were the most common CT findings seen at the biopsy sites. All of the transbronchial lung biopsy specimens showed a thickened bronchiolar wall and bronchiolar and peribronchiolar inflammation at histopathologic analysis. Dilated bronchioles were identified in 19 (86%) patients, and epithelioid granulomas with or without caseation were seen in seven (32%).
  
  
  CONCLUSIONS
  Regardless of the specific infective mycobacterial species, the most common thin-section CT findings of NTM pulmonary infection are bilateral small nodules, cylindric bronchiectasis, and branching centrilobular nodules. These findings correspond histopathologically to bronchiolectasis and bronchiolar and peribronchiolar inflammation with or without granuloma formation.
authors.affiliation: Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Ilwon-Dong, Kangnam-Ku, Seoul 135-710, Korea.
authors.forename: Yeon Joo
authors.initials: YJ
authors.lastname: Jeong
authors.forename: Kyung Soo
authors.initials: KS
authors.lastname: Lee
authors.forename: Won-Jung
authors.initials: WJ
authors.lastname: Koh
authors.forename: Joungho
authors.initials: J
authors.lastname: Han
authors.forename: Tae Sung
authors.initials: TS
authors.lastname: Kim
authors.forename: O Jung
authors.initials: OJ
authors.lastname: Kwon
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D007121:Immunocompetence; D008168:Lung / Q000000981:diagnostic imaging* / Q000473:pathology; D008171:Lung Diseases / Q000000981:diagnostic imaging* / Q000382:microbiology*; D008297:Male; D008875:Middle Aged; D009165:Mycobacterium Infections, Nontuberculous / Q000000981:diagnostic imaging* / Q000276:immunology / Q000473:pathology; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed