The Usefulness of Whole-blood Interferon-gamma Release Assay for the Diagnosis of Extra-pulmonary Tuberculosis.
10.4046/trd.2009.67.4.331
- Author:
Hye Min LEE
1
;
Sung Gun CHO
;
Hyung Koo KANG
;
Sung Woon PARK
;
Byung Ook LEE
;
Jae Hee LEE
;
Eun Ju JEON
;
Jae Chol CHOI
Author Information
1. Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Chung-Ang University College of Medicine, Seoul, Korea. medics27@cau.ac.kr
- Publication Type:Original Article
- Keywords:
Mycobacterium tuberculosis;
Interferon-gamma;
Diagnosis
- MeSH:
Hand;
Humans;
Interferon-gamma;
Interferon-gamma Release Tests;
Lymphadenitis;
Mycobacterium tuberculosis;
Pleurisy;
Retrospective Studies;
Tuberculosis;
Tuberculosis, Pulmonary;
Victoria
- From:Tuberculosis and Respiratory Diseases
2009;67(4):331-337
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
BACKGROUND: The whole-blood interferon-gamma release assay (QuantiFERON-TB Gold [QFT-G]: Cellestis, Carnegie, Victoria, Australia) has been studied primarily for the use of diagnosing active pulmonary tuberculosis (TB) or latent TB. In the present study, the usefulness of QFT-G was evaluated for the diagnosis of extra-pulmonary tuberculosis (EP-TB). METHODS: From June 2006 to February 2009, we evaluated the usefulness of QFT-G in patients (n=65) suspected with EP-TB, retrospectively. The diagnostic sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the QFT-G assay were analyzed. RESULTS: EP-TB was diagnosed in 33 (51%) participants. The overall sensitivity, specificity, PPV, and NPV of the QFT-G assay for EP-TB were 78%, 79%, 81%, and 77%, respectively. Of the 33 with EP-TB, 14 (42%) were diagnosed with TB pleurisy, 7 (21%) with TB lymphadenitis, 7 (21%) with intestinal TB, and 5 (15%) with EP-TB in other sites. In subgroup analyses according by site of infection, the QFT-G showed 86% sensitivity, 64% specificity, and 78% NPV in TB pleurisy. On the other hand, the sensitivity, specificity, and NPV of the assay were 71%, 83% and 71%, respectively in TB lymphadenitis, and 86%, 100% and 88%, respectively in intestinal TB. Among the patients with suspected alternative site EP-TB, the sensitivity, specificity, and NPV of the assay were 50%, 80% and 67%, respectively. CONCLUSION: The QFT-G assay showed moderate diagnostic accuracy in EP-TB. However, negative QFT-G assay does not exclude EP-TB because of the low NPV of this assay.
