Evaluation of Xpert MTB/RIF Ultra performance for pulmonary tuberculosis diagnosis on smear-negative respiratory samples in a French centre

Collection Location Koleksi E-book & E-Journal Perpustakaan Pusat Unila
Edition Vol. 38, Issue 3
Call Number
ISBN/ISSN 1435-4373
Author(s) Hodille, Elisabeth...[et al.]
Subject(s) Biomedicine
Classification NONE
Series Title
GMD E-Journal
Language English
Publisher Springer
Publishing Year 2019
Publishing Place Switzerland
Abstract/Notes Abstract
Tuberculosis (TB) is a worldwide public health concern, including in high-resource countries with a low prevalence of TB. Xpert
MTB/RIF assay was developed to improve TB and rifampicin (RIF) resistance detection, but sensitivity remains poor on smearnegative
sputum. XpertMTB/RIF Ultra assay was designed to enhance the sensitivity of TB detection in clinical samples. Herein,
we evaluated retrospectively the performance of this test on smear-negative respiratory samples. Respiratory specimens with
smear-negative and a Mycobacterium tuberculosis (MTB) complex-positive culture were retrospectively selected from those
taken from patients during routine care, and analysed in the Mycobacteria Laboratory of the Lyon University hospital, France.
Specimens were stored at − 20 °C before testing by Xpert MTB/RIF Ultra. For each sample, growth delay and date of anti-TB
treatment initiation were recorded. Forty-six samples—29 sputum, 8 bronchial aspirates, 6 broncho-alveolar lavages, and 3
gastric aspirates—were selected. Among samples collected before treatment initiation (n = 33), sensitivity was 81.8% (95% CI
[64.5; 93.0]) and there was a significant correlation between the quantitative measurements (Ct) of Xpert MTB/RIF Ultra assay
and the time to growth detection in culture. Among samples collected after treatment initiation (n = 12), sensitivity was 100%,
without correlation with time to growth detection due to presence of afterglow DNA in samples. In high-resource settings, the
Xpert MTB/RIF Ultra test represents a useful tool for pulmonary TB diagnosis, notably for the paucibacillary forms. Moreover,
quantitative measurement of Xpert MTB/RIF Ultra could help to predict time to MTB culture positivity and be used as a quality
indicator of MTB culture process.
Keywords XpertMTB/RIF Ultra . Pulmonary tuberculosis . Diagnosis . High-resource setting . Smear-negative
Specific Detail Info
  Back To Previous