Diagnostic implications of inconsistent results obtained with the Xpert MTB/Rif assay in detection of Mycobacterium tuberculosis isolates with an rpoB mutation associated with low-level rifampin resistance

Akos Somoskovi; Vanessa Deggim; Diana Ciardo; Guido V Bloemberg

doi:10.1128/JCM.01377-13

Diagnostic implications of inconsistent results obtained with the Xpert MTB/Rif assay in detection of Mycobacterium tuberculosis isolates with an rpoB mutation associated with low-level rifampin resistance

J Clin Microbiol. 2013 Sep;51(9):3127-9. doi: 10.1128/JCM.01377-13. Epub 2013 Jul 12.

Authors

Akos Somoskovi¹, Vanessa Deggim, Diana Ciardo, Guido V Bloemberg

Affiliation

¹ Institut für Medizinische Mikrobiologie Universität Zürich, Zürich, Switzerland. asomoskoevi@imm.uzh.ch

Abstract

Xpert-MTB/Rif is one of the most frequently used molecular screening tests for multidrug-resistant tuberculosis worldwide. We report false-negative assay results in the presence of rpoB Leu533Pro, which is associated with low-level phenotypic rifampin resistance. Accurate and timely confirmation of rifampin susceptibility results obtained with Xpert-MTB/Rif is imperative.

Publication types

Case Reports

MeSH terms

Aged
Bacterial Proteins / genetics*
Bacteriological Techniques / methods
DNA-Directed RNA Polymerases
Drug Resistance, Bacterial*
False Negative Reactions*
Humans
Male
Molecular Diagnostic Techniques / methods*
Mutation, Missense*
Mycobacterium tuberculosis / drug effects
Mycobacterium tuberculosis / genetics
Mycobacterium tuberculosis / isolation & purification*
Tuberculosis, Multidrug-Resistant / diagnosis*
Tuberculosis, Multidrug-Resistant / microbiology

Substances

Bacterial Proteins
rpoB protein, Mycobacterium tuberculosis
DNA-Directed RNA Polymerases