PT  - JOURNAL ARTICLE
AU  - Belén Saavedra
AU  - Edson Mambuque
AU  - Dinis Nguenha
AU  - Neide Gomes
AU  - Shilzia Munguambe
AU  - Juan Ignacio García
AU  - Santiago Izco
AU  - Sozinho Acacio
AU  - Adrià Murias-Closas
AU  - Marta Cossa
AU  - Irene Losada
AU  - Hadrián Pernas-Pardavila
AU  - Laura Oliveras
AU  - Grant Theron
AU  - Alberto L. García-Basteiro
TI  - Performance of Xpert MTB/RIF Ultra for tuberculosis diagnosis in the context of passive and active case finding
AID  - 10.1183/13993003.00257-2021
DP  - 2021 Dec 01
TA  - European Respiratory Journal
PG  - 2100257
VI  - 58
IP  - 6
4099  - http://erj.ersjournals.com/content/58/6/2100257.short
4100  - http://erj.ersjournals.com/content/58/6/2100257.full
SO  - Eur Respir J2021 Dec 01; 58
AB  - Aims We present a field evaluation of the diagnostic accuracy of Xpert MTB/RIF (“Xpert”) and Xpert MTB/RIF Ultra (“Ultra”) using two cohorts in a high tuberculosis/HIV burden setting in Southern Mozambique.Methods Single respiratory specimens from symptomatic adults accessing healthcare services (passive case finding (PCF) cohort) and from household and community close contacts (active case finding (ACF) cohort) were tested by smear microscopy, culture, Xpert and Ultra. Liquid and solid culture served as a composite reference standard. We explored the impact of trace results on specificity via their recategorisation to negative (in all and just among those previously treated individuals).Results 1419 and 252 participants were enrolled in the PCF and ACF cohorts, respectively. For the PCF cohort, Ultra showed higher sensitivity than Xpert overall (0.95 (95% CI 0.90–0.98) versus 0.88 (96% CI 0.82–0.93); p<0.001) and among smear-negative patients (0.84 (96% CI 0.71–0.93) versus 0.63 (96% CI 0.48–0.76)). Ultra's specificity was lower than Xpert's (0.96 (96% CI 0.95–0.97) versus 0.98 (96% CI 0.97–0.99); p=0.008). For ACF, sensitivities were the same (0.67 (95% CI 0.22–0.96) for both tests), although Ultra detected a higher number of microbiologically confirmed samples than Xpert (4.7% (12 out of 252) versus 2.7% (seven out of 252)). Conditional recategorisation of trace results among previously treated participants maintained differences in specificity in the PCF cohort.Conclusion These results add evidence on the improved sensitivity of Ultra and support its use in different case finding scenarios.Ultra has higher sensitivity and lower specificity than Xpert for passive case finding. Lower specificity estimates do not seem to be driven by false-positive results among previously treated participants. https://bit.ly/3wcsg62