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Updated: Jan 30, 2026

Diagnosing Pulmonary Tuberculosis with the Xpert MTB/RIF Test
Published on: April 9, 2012
[CLINICAL ANALYSIS OF 115 PULMONARY TUBERCULOSIS PATIENTS WITH SPUTUM SMEAR-NEGATIVE]
Abstract:
[Methods] We retrospectively studied 115 con- secutive pulmonary tuberculosis patients whose sputum smear was .negative, diagnosed by positive culture and/or PCR of various samples, or positive QFT. [Results] The culture positive rate of tuberculosis by spu- tum, gastric aspirate, bronchoscopy, and computed tomogra- phy (CT)-guided needle biopsy samples was 55.7%, 45.6%, 73.2%, and 71.4%, respectively. In multivariate analysis, negative or unknown sputum PCR, negative or unknown gastric aspirate, and minimal spread of tuberculosis were risk factors for negative culture from both sputum and gas- tric aspirate. Sputum culture was positive in only one of the four patients with multi-drug resistant Mycobacterium tuberculosis. [Conclusion] Invasive diagnostic procedures such as fiber- optic bronchoscopy should be considered in patients with negative sputum PCR and minimal spread of tuberculosis.
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