Link to the University of Pittsburgh Homepage
Link to the University Library System Homepage Link to the Contact Us Form

A novel sample processing method for rapid detection of tuberculosis in the stool of pediatric patients using the Xpert MTB/RIF assay

Banada, PP and Naidoo, U and Deshpande, S and Karim, F and Flynn, JL and O'Malley, M and Jones, M and Nanassy, O and Jeena, P and Alland, D (2016) A novel sample processing method for rapid detection of tuberculosis in the stool of pediatric patients using the Xpert MTB/RIF assay. PLoS ONE, 11 (3).

[img]
Preview
PDF
Published Version
Available under License : See the attached license file.

Download (775kB)
[img] Plain Text (licence)
Available under License : See the attached license file.

Download (1kB)

Abstract

© 2016 Banada et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Background: Tuberculosis (TB) is difficult to diagnose in children using molecular tests, because children have difficulty providing respiratory samples. Stool could replace sputum for diagnostic TB testing if adequate sample processing techniques were available. Methods We developed a rapid method to process large volumes of stool for downstream testing by the Xpert MTB/RIF (Xpert) TB-detection assay. The method was tested and optimized on stool samples spiked with known numbers of M. tuberculosis colony forming units (CFU), and stools from M. tuberculosis-infected cynomolgus macaques (Macaca fascicularis). Performance was scored on number of positive Xpert tests, the cycle thresholds (Cts) of the Xpert sample-processing control (SPC), and the Cts of the M. tuberculosis-specific rpoB probes. The method was then validated on 20 confirmed TB cases and 20 controls in Durban, South Africa. Results: The assay's analytical limit of detection was 1,000 CFU/g of stool. As much as one gram of spiked stool could be tested without showing increased PCR inhibition. In analytical spiking experiments using human stool, 1 g samples provided the best sensitivity compared to smaller amounts of sample. However, in Macaques with TB, 0.6g stool samples performed better than either 0.2g or 1.2g samples. Testing the stool of pediatric TB suspects and controls suggested an assay sensitivity of 85% (95% CI 0.6-0.9) and 84% (95% CI 0.6-0.96) for 0.6g and 1.2g stool samples, respectively, and a specificity of 100% (95% CI 0.77-1) and 94% (95% CI 0.7-0.99), respectively. Conclusion: This novel approach may permit simple and rapid detection of TB using pediatric stool samples.


Share

Citation/Export:
Social Networking:
Share |

Details

Item Type: Article
Status: Published
Creators/Authors:
CreatorsEmailPitt UsernameORCID
Banada, PP
Naidoo, U
Deshpande, S
Karim, F
Flynn, JLjoanne@pitt.eduJOANNE
O'Malley, M
Jones, M
Nanassy, O
Jeena, P
Alland, D
Contributors:
ContributionContributors NameEmailPitt UsernameORCID
EditorRengarajan, JyothiUNSPECIFIEDUNSPECIFIEDUNSPECIFIED
Date: 1 March 2016
Date Type: Publication
Access Restriction: No restriction; Release the ETD for access worldwide immediately.
Journal or Publication Title: PLoS ONE
Volume: 11
Number: 3
DOI or Unique Handle: 10.1371/journal.pone.0151980
Institution: University of Pittsburgh
Schools and Programs: School of Medicine > Microbiology and Molecular Genetics
Refereed: Yes
Date Deposited: 25 Aug 2016 15:57
Last Modified: 04 Feb 2019 15:56
URI: http://d-scholarship.pitt.edu/id/eprint/28280

Metrics

Monthly Views for the past 3 years

Plum Analytics

Altmetric.com


Actions (login required)

View Item View Item