# name
Correlation of Xpert MTB/RIF with measures to assess
                Mycobacterium tuberculosis bacillary burden in high HIV burden
                areas of Southern Africa

# metadata.dc.description.abstract[].value
Traditionally, smear microscopy has been used as a point-of-care
                measure of bacillary burden in tuberculosis patients to inform
                infection control and contact tracing. Xpert MTB/RIF has the
                potential to replace smear. However, data to support the use of
                its quantitative output [cycle threshold (CT)] as an alternate
                point-of-care measure of bacillary burden are limited. This
                study assessed the correlation (Spearman's) between CT, smear,
                culture time-to-positivity (TTP), and clinical factors in
                patients with Xpert-positive sputum from Mozambique (n = 238)
                and South Africa (n = 462). Mean CT and smear grade correlated
                well (rho0.72); compared to TTP and smear (rho0.61); and mean CT
                and TTP (rho0.50). In multivariate analyses, lower CT (higher
                bacillary load) was associated with negative HIV serostatus and
                low BMI. A smear positivity rule-out (95% sensitivity) CT
                cut-off of 28.0 was identified, with 54.1% specificity, 2.07
                positive likelihood ratio, 0.09 negative likelihood ratio and
                79.0% correctly classified. Cut-offs were higher for HIV
                positive compared to HIV negative individuals for any set
                sensitivity level. This study suggests Xpert CT values correlate
                well with smear, both in HIV positive and negative individuals,
                and that CT cut-offs might be broadly applicable to multiple
                settings. Studies to directly assess the association of CT with
                infectiousness are needed.

# metadata.dc.relation.ispartof[].value
Scientific Reports, 2018, vol. 8, num. 5201

# metadata.dc.source[].value
Articles publicats en revistes (ISGlobal)

# metadata.dc.title[].value
Correlation of Xpert MTB/RIF with measures to assess
                Mycobacterium tuberculosis bacillary burden in high HIV burden
                areas of Southern Africa