Infection

, Volume 41, Issue 1, pp 187–194

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

Authors

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