Performance of the Xpert MTB/RIF Ultra Assay for Determining Cause of Death by TB in Tissue Samples Obtained by Minimally Invasive Autopsies

Alberto L García‐Basteiro ,Cesaltina Lorenzoni,Mamudo R Ismail,Anélsio Cossa,Miguel J Martínez,Paola Castillo,Ariadna Sanz,Carla Carrilho,Juan Carlos Hurtado,Natalia Rakislova,Inácio Mandomando,Quique Bassat,Mireia Navarro,Llorenç Quintó,Frank Cobelens,Miriam J Álvarez-Martínez ,Jaume Ordï ,Fabíola Fernandes ,Áurea Mira ,Lucília Lovane ,Jordi Vilà ,Dércio Jordão ,Irene Casas ,Clara Menéndez

doi:10.1016/j.chest.2020.06.071

Abstract

Performance of the Xpert MTB/RIF Ultra Assay for Determining Cause of Death by TB in Tissue Samples Obtained by Minimally Invasive Autopsies

Highlights

To the Editor: An estimated 1.5 million deaths were attributable to TB in 2018.1 some uncertainty exists as to the exact global figures, given that approximately 30% of incident cases are not diagnosed, and because of the difficulties of ascertaining TB as cause of death (CoD).[2]
We evaluated the diagnostic accuracy of the molecular Xpert MTB/RIF Ultra assay in samples obtained by minimally invasive autopsy (MIA) to detect CoD by TB
This analysis shows that Xpert Ultra can be directly applied to specific MIA samples and achieve a reasonably high accuracy for confirming or ruling out TB as the CoD

Summary

Introduction

To the Editor: An estimated 1.5 million deaths were attributable to TB in 2018.1 some uncertainty exists as to the exact global figures, given that approximately 30% of incident cases are not diagnosed, and because of the difficulties of ascertaining TB as cause of death (CoD).[2]. An alternative minimally invasive autopsy (MIA), a procedure well accepted by the of kin, has been developed.[4,5] MIA can be conducted relatively rapidly with the use of biopsy needles for sampling key organs, which leave barely visible marks, which is more acceptable to relatives This method has shown good sensitivity for diagnosing TB as CoD.[6] MIA has far used standard histological and microbiological approaches for TB diagnosis (identification of granulomatous lesions, acid-fast bacilli smears, in-house polymerase chain reaction methods),[7] which remain time consuming, require specific expertise, and have limited sensitivity. We evaluated the diagnostic accuracy of the molecular Xpert MTB/RIF Ultra (hereafter referred to as Xpert Ultra) assay in samples obtained by MIA to detect CoD by TB

Methods

Results

Conclusion