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Updated: Feb 1, 2026

Diagnosing Pulmonary Tuberculosis with the Xpert MTB/RIF Test
Published on: April 9, 2012
Urine Xpert MTB/RIF for the diagnosis of childhood tuberculosis
Anna Lena Lopez1, Josephine G Aldaba1, Merrylle Morales-Dizon1
1Institute of Child Health and Human Development, National Institutes of Health, University of the Philippines Manila, Manila, Philippines.
Introduction:
Xpert MTB/RIF is recommended for the simultaneous detection of tuberculosis (TB) and rifampicin resistance directly from sputum specimens. Since young children cannot always expectorate, we assessed urine as a possible specimen source to diagnose TB in children using Xpert MTB/RIF.
Methods:
During a field study to enhance childhood TB identification, spot urine samples were prospectively collected from consecutive ambulatory children aged 0 to 14 years presenting with presumptive pulmonary TB in community health centers. Urine Xpert MTB/RIF was performed by blinded technicians in 182 samples using 2ml of unprocessed urine.
Results:
The mean age of presumptive TB cases was 5.9 years (median 5.4, range 0.1 to 14.7) with more males (113, 62%) compared to females. All urine samples tested negative for Xpert MTB/RIF, regardless of whether concentration was performed or not. Out of these 182 presumptive TB cases, 50 (28%) were clinically diagnosed and 5 (3%) were bacteriologically diagnosed to have TB disease using either sputum or nasopharyngeal aspirate specimens.
Conclusions:
In this community-based study, urine Xpert MTB/RIF does not appear to contribute to the diagnosis of childhood TB.
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