Article Text
Abstract
Introduction Childhood pulmonary tuberculosis (TB) remains a diagnostic challenge. This study aimed to evaluate the performance of Xpert Ultra for the diagnosis of pulmonary TB in children in a low TB prevalence setting.
Methods Prospective, multicentre, diagnostic accuracy study. Children with clinical or radiological suspicion of pulmonary TB were recruited at 11 paediatric units in Spain. Up to three gastric or sputum specimens were taken on 3 consecutive days, and analysed by Xpert MTB/RIF, Xpert Ultra and culture in parallel.
Results 86 children were included (median age 4.9 years, IQR 2.0–10.0; 51.2% male). The final diagnosis was pulmonary TB in 75 patients (87.2%); 33 (44.0%) were microbiologically confirmed. A total of 219 specimens, comprising gastric aspirates (n=194; 88.6%) and sputum specimens (n=25; 11.4%), were analysed. Using culture as reference standard and comparing individual specimens, the sensitivity was 37.8% (14/37) for Xpert MTB/RIF and 81.1% (30/37) for Xpert Ultra (p<0.001); specificity was 98.4% (179/182) and 93.4% (170/182), respectively (p=0.02). In the per-patient analysis, considering positive results on any specimen, the sensitivity was 42.9% (9/21) for Xpert MTB/RIF and 81.0% for Xpert Ultra (17/21, p=0.01); specificity was 96.9% (63/65) and 87.7% (57/65, p=0.07), respectively.
Conclusions In children with pulmonary TB in a low burden setting, Xpert Ultra has significantly higher sensitivity than the previous generation of Xpert assay and only marginally lower specificity. Therefore, in children undergoing evaluation for suspected pulmonary TB, Xpert Ultra should be used in preference to Xpert MTB/RIF whenever possible.
- Tuberculosis
- Paediatric Lung Disaese
- Respiratory Infection
Data availability statement
Data are available upon reasonable request.
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Data availability statement
Data are available upon reasonable request.
Footnotes
DA-A and GS-G are joint first authors.
MT and BS-G are joint senior authors.
Twitter @DavidAguileraAl, @tonisoriano66
Contributors BS-G and MT conceived of the study. BS-G, MT, DA-A, and JS-L designed the study. GS-G, DA-A and BS-G cleaned and analysed the data, and constructed the figures and tables. DA-A, GS-G, BS-G, JS-L and MT wrote the first draft of the manuscript. BS-G and DA-A are responsible for the overall content as guarantors. All authors contributed data to the study, contributed to the data interpretation, critically reviewed the manuscript and approved the final manuscript for submission. MT and BS-G are joint last authors.
Funding This study did not receive any project-specific funding. DA-A was supported by the Spanish Ministry of Health – Instituto de Salud Carlos III (ISCIII) and cofunded by the European Union (FEDER) (Contrato Río Hortega CM18/00100). AN-J was supported by 'Subvencions per a la Intensificació de Facultatius Especialistes' (Departament de Salut de la Generalitat de Catalunya, Programa PERIS 2016-2020) (SLT008/18/00193). DBG was supported by the Spanish Ministry of Science and Innovation – Instituto de Salud Carlos III and Fondos FEDER by 'Contratos para la intensificación de la actividad investigadora en el Sistema Nacional de Salud, 2020 (INT20/00086)'. BS-G was supported by the Spanish Ministry of Health – Instituto de Salud Carlos III (ISCIII) and cofunded by the European Union (FEDER) (Contrato Juan Rodés JR16/00036). Xpert cartridges were kindly provided by Cepheid, Sunnyvale, CA, USA.
Competing interests MT has received support for conference attendance from Cepheid in the past. The remaining authors declare that they have no potential conflicts of interest.
Provenance and peer review Not commissioned; externally peer reviewed.
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