Jin Kyoung Kim, Presenter: Nothing to Disclose

Jae Seung Seo, Abstract Co-Author: Nothing to Disclose

Chul Gu Park, Abstract Co-Author: Nothing to Disclose

Hyun Jeoung Pyo, Abstract Co-Author: Nothing to Disclose

Jun Soo Byun MD, Abstract Co-Author: Nothing to Disclose

Semin Chong MD, Abstract Co-Author: Nothing to Disclose

The aim of this study was to evaluate the usefulness of chest CT, the whole blood interferon-r (IFN-r) assay and polymerase chain reaction (PCR) in the diagnosis of active pulmonary tuberculosis (TB) in acid-fast bacilli (AFB) smear-negative patients who are clinically suspected as active pulmonary TB.

In this retrospective evaluation, we reviewed data of the patients who had been suspected as active pulmonary TB with negative of AFB smear on the basis of clinical and radiographic features for last two years. During these periods, 168 patients were visited our institute with suspicion of having pulmonary TB. After exclusion of smear-positive (n=74) and inconclusive diagnosis cases (n=10), we conducted our study in 84 patients.

Active TB was diagnosed in 39 of 84 participants (46%). The sensitivity, specificity, PPV and NPV of the PCR for the diagnosis of active TB was 44.4%, 97.7%, 94.1% and 5.9%. The sensitivity, specificity, PPV and NPV of the chest CT for the diagnosis of active TB was 89.7%, 66.7%, 70% and 88.2%, respectively. The IFN-r assay was available in 75 patients. The sensitivity, specificity, PPV and NPV of the IFN-r assay for the diagnosis of active TB was 83.9%, 81.8%, 76.5% and 87.8%. Among patients who suggested as TB by chest CT, the 24 patients showed positive IFN-r assay results. The sensitivity, specificity, PPV and NPV of the chest CT and the IFN-r assay for the diagnosis of active TB was 85.2%, 92.9%, 95.8% and 76.5%, respectively.

Where the prevalence of TB is intermediate, it is evaluated that combined results of chest CT and the IFN-r assay were used as the most exact method in predicting TB diagnosis in patients with AFB stain negative pulmonary TB.

Evaluation for the combined results of chest CT and the IFN-r assay were used as the most exact method in predicting TB diagnosis in patients with AFB stain negative pulmonary TB.

Kim, J, Seo, J, Park, C, Pyo, H, Byun, J, Chong, S, Multimodality Approach in the Diagnosis of Active Pulmonary Tuberculosis in Acid-fast Bacilli Smear-Negative Patients: Comparison of Chest CT, the Whole Blood Interferon-r Assay, and Polymerase Chain Reaction.  Radiological Society of North America 2009 Scientific Assembly and Annual Meeting, November 29 - December 4, 2009 ,Chicago IL. http://archive.rsna.org/2009/8005369.html