Infection

, Volume 41, Issue 1, pp 187–194

Predictive factors for tuberculosis in patients with a TB-PCR-negative bronchial aspirate

  • C. H. Kim
  • J. K. Lim
  • S. Y. Lee
  • D. I. Won
  • S. I. Cha
  • J. Y. Park
  • W. K. Lee
  • J. Lee
Clinical and Epidemiological Study

DOI: 10.1007/s15010-012-0394-7

Cite this article as:
Kim, C.H., Lim, J.K., Lee, S.Y. et al. Infection (2013) 41: 187. doi:10.1007/s15010-012-0394-7

Abstract

Purpose

Pulmonary tuberculosis (PTB), with a tuberculosis (TB)-polymerase chain reaction (PCR)-negative bronchial aspirate (BA), but a positive culture result is often encountered in clinical practice. However, limited data are available concerning clinical judgment in patients with suspected PTB and a TB-PCR-negative BA pending culture results. The present study aimed to identify predictors for PTB in patients with a TB-PCR-negative BA.

Methods

A retrospective study was conducted on patients who had undergone a bronchoscopy because of suspected PTB. Clinical, laboratory, and computed tomography (CT) findings were investigated in PTB patients with TB-PCR-negative but positive culture BA results, and non-PTB patients with a radiographic lesion comparable to the former.

Results

Of 250 patients screened, 31 (12 %) were diagnosed with PTB by positive culture results only. Of these 31 patients, 30 (97 %) had a lesion within one-third of the hemithorax as determined by chest radiography. In the final analysis of 30 PTB and 65 non-PTB patients with comparable radiographic lesions, a positive QuantiFERON-TB Gold In-Tube (QFT) result was independently associated with an increased risk of a positive TB culture. CT findings of consolidation were a negative predictor for PTB. Patients with a negative QFT result and consolidation had a negative predictive value of 95 % for PTB, while patients with a positive QFT result and nodular CT abnormalities without consolidation had a positive predictive value of 86 % for PTB.

Conclusion

The simple combination of CT findings of consolidation and QFT test results may help clinicians to refine decision-making in patients with a TB-PCR-negative BA.

Keywords

BronchoscopyInterferon-gamma release assayTuberculosisPolymerase chain reactionComputed tomography

Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  • C. H. Kim
    • 1
  • J. K. Lim
    • 2
  • S. Y. Lee
    • 1
  • D. I. Won
    • 3
  • S. I. Cha
    • 1
  • J. Y. Park
    • 1
  • W. K. Lee
    • 3
  • J. Lee
    • 1
  1. 1.Department of Internal MedicineSchool of Medicine, Kyungpook National UniversityDaeguSouth Korea
  2. 2.Department of RadiologySchool of Medicine, Kyungpook National UniversityDaeguSouth Korea
  3. 3.Department of Clinical PathologySchool of Medicine, Kyungpook National UniversityDaeguSouth Korea