Differences in CT Findings According to Sputum Smear Results in Patients with Active Pulmonary Tuberculosis Having a Single Cavity

한 개의 공동이 있는 활동성폐결핵 환자에서 객담도말검사 결과에 따른 흉부CT 소견의 차이

  • Song, In Sup (Department of Diagnostic Radiology, Chung Ang University Hospital) ;
  • Lee, Hwa Yeun (Department of Diagnostic Radiology, Chung Ang University Hospital) ;
  • Yoo, Seung Min (Department of Diagnostic Radiology, Guro Saint's Mary Hospital)
  • 송인섭 (중앙대학교 의과대학 영상의학과교실) ;
  • 이화연 (중앙대학교 의과대학 영상의학과교실) ;
  • 유승민 (구로성모병원 영상의학과)
  • Received : 2007.04.20
  • Accepted : 2007.05.18
  • Published : 2007.06.30

Abstract

Background: The purpose of this study was to evaluate the differences in CT findings according to sputum smear-positive or -negative results in patients with active pulmonary tuberculosis having a single cavity. Methods: A total of 32 patients with active pulmonary tuberculosis having a single cavity on CT were classified into two groups: smear-positive (n=19) and smear-negative (n=13). The CT findings were reviewed retrospectively. The presence of consolidation, the number of lobes showing consolidation, ground-glass opacity, micronodules and nodule, the maximum diameter of the cavity, and the shape and maximum thickness of the cavity wall were assessed. Result: The maximum diameter of the cavity was $33.84{\pm}13.65mm$ and $27.08{\pm}9.04mm $ in the smear-positive and -negative groups, respectively (p>0.05). The amount of consolidation and the number of lobes with consolidation were found to be 89.5% and 30.8% (p=0.01) and $1.37{\pm}0.90$ and $0.31{\pm}0.48$ (p=0.0002) in the smear-positive and -negative groups, respectively. Consolidations in two or more lobes were only noted in 31.6% of in the sputum smear- positive group (p< 0.05). There were no other significant differences between the two groups. The sensitivity, specificity, positive and negative predictive values for the presence of consolidation were 89.5%, 69.2%, 73.9%, and 81.8%, respectively. Conclusion: While the absence of consolidation on CT may be associated with sputum smear-negative results in patients with active pulmonary tuberculosis having a single cavity, the presence of consolidation in two or more lobes on CT may be associated with spear-positive results in these patients.

배 경: 한 개의 공동이 있는 활동성 폐결핵환자에서 객담도말검사 결과와 관련된 흉부CT 소견을 알아보고자 하였다. 방 법: 흉부CT에서 한 개의 공동이 있는 32명의 활동성 폐결핵환자를 대상으로 하였다. 객담도말검사의 결과에 따라 객담도말검사 양성(n=19)과 음성(n=13)인 두 군으로 나누었다. 흉부CT 소견을 후향적으로 분석하였다. 흉부CT 소견은 공동의 크기, 공동 벽의 모양, 공동 벽의 최대 두께, 그리고 동반된 소견들을 분석하였다. 공동의 크기는 최대직경으로 하였다. 동반된 소견은 간유리음영, 폐경결 미세결절과 결절로 나누어 분석하였다. 각 소견의 유무와 소견이 보이는 폐엽의 수를 기록하였다. 두 군 간에 흉부CT 소견에 어떤 차이가 있는지 알아보았다. 결 과: 공동의 평균 최대직경은 객담도말검사 양성인 군은 $33.84{\pm}13.65mm$이었고, 음성인 군은 $27.08{\pm}9.04 mm$로 음성인 군에서 작은 경향이 있었으나 통계적으로 의미 있는 차이는 없었다(p>0.05). 폐경결은 객담도말검사 양성인 군은 89.5%, 음성인 군은 30.8%에서 보였고(p=0.01), 폐경결이 보이는 폐엽의 수는 객담도말 양성인 군은 평균 $1.37{\pm}0.90$, 음성인 군은 평균 $0.31{\pm}0.48$개로 두 군 간에 의미 있는 차이가 있었다(p=0.0002). 두 개 이상의 폐엽에 폐경결이 동반된 예는 객담도말검사 양성인 군의 31.6%에서 있었고 음성인 군에서는 없었다(p<0.05). 다른 소견들은 두 군 간에 차이가 없었다(p>0.05). 객담도말검사에 대한 폐경결의 민감도, 특이도, 양성예측도, 그리고 음성예측도는 각각 89.5%, 69.2%, 73.9%, 81.8% 이었다.

Keywords

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