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. 2018 Jan;146(2):246-255.
doi: 10.1017/S0950268817002746. Epub 2017 Dec 6.

The impact of implementing a Xpert MTB/RIF algorithm on drug-sensitive pulmonary tuberculosis: a retrospective analysis

K Rees  1 , N Muditambi  1 , M Maswanganyi  2 , J Railton  1 , J A McIntyre  1 , H E Struthers  1 , P B Fourie  3 , R P H Peters  1
Affiliations

The impact of implementing a Xpert MTB/RIF algorithm on drug-sensitive pulmonary tuberculosis: a retrospective analysis

K Rees et al. Epidemiol Infect. 2018 Jan.

Abstract

Xpert MTB/RIF (Xpert) is the preferred first-line test for all persons with tuberculosis (TB) symptoms in South Africa in line with a diagnostic algorithm. This study evaluates pre- and post-implementation trends in diagnostic practices for drug-sensitive, pulmonary TB in adults in an operational setting, following the introduction of the Xpert-based algorithm. We retrospectively analysed data from the national TB database for Greater Tzaneen sub-district, Limpopo Province. Trends in a number of cases, diagnosis and outcome and characteristics associated with death are reported. A total of 8407 cases were treated from 2008 until 2015, with annual cases registered decreasing by 31·7% over that time period (from 1251 to 855 per year). After implementation of Xpert, 69·9% of cases were diagnosed by Xpert, 29·4% clinically, 0·6% by smear microscopy and 0·1% by culture. Cases with a recorded microbiological test increased from 76·2% to 96·4%. Cases started on treatment without confirmation, but with a negative microbiological test increased from 7·1% to 25·7%. Case fatality decreased from 15·0% to 9·8%, remaining consistently higher in empirically treated groups, regardless of HIV status. Implementation of the algorithm coincided with a reduced number of TB cases treated and improved coverage of microbiological testing; however, a substantial proportion of cases continued to start treatment empirically.

Keywords: Diagnostic trend; HIV; Xpert; tuberculosis.

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Conflict of interest statement

None.

Figures

Fig. 1.
Fig. 1.
Method of diagnosis of drug-sensitive, pulmonary TB cases started on treatment in Greater Tzaneen sub-district, 2008–2015. *Growth of ART programme: figures for the whole of Mopani District.
Fig. 2.
Fig. 2.
The proportion of confirmed or empirically treated drug-sensitive, pulmonary TB cases started on treatment in Greater Tzaneen sub-district, 2008–2015.
Fig. 3.
Fig. 3.
Population rates (per 100 000 people) of drug-sensitive, pulmonary TB cases started on treatment in Greater Tzaneen sub-district, 2011–2015 in (a) the total (b) HIV positive and (c) HIV negative populations.
Fig. 4.
Fig. 4.
A number of deaths and case fatality rate in drug-sensitive, pulmonary TB cases started on treatment, stratified into confirmed TB and unconfirmed TB, in Greater Tzaneen sub-district, 2008–2015.
See this image and copyright information in PMC

References

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