Journal Article > ResearchFull Text
Int J Tuberc Lung Dis. 2009 June 1; Volume 13 (Issue 6); 791-793.
Trollip AP, Albert H, Mole R, Marshall T, van Cutsem G, et al.
Int J Tuberc Lung Dis. 2009 June 1; Volume 13 (Issue 6); 791-793.
Modifications in the FASTPlaqueTB test protocol have resulted in an increase in the analytical limits of detection. This study investigated whether the performance of a modified prototype was able to increase the detection of smear-negative, culture-positive sputum samples as compared to the first generation FASTPlaqueTB test. Modifications to the FASTPlaqueTB did result in increased detection of smear-negative samples, but this was associated with a decrease in the specificity of the test. Before the FASTPlaqueTB can be considered as a viable replacement for smear microscopy and culture for the identification of tuberculosis, further work is required to resolve the performance issues identified in this study.
Journal Article > ResearchFull Text
Lancet. 2011 April 19; Volume 377 (Issue 9776); DOI:10.1016/S0140-6736(11)60438-8
Boehme CC, Nicol MP, Nabeta P, Michael JS, Gotuzzo E, et al.
Lancet. 2011 April 19; Volume 377 (Issue 9776); DOI:10.1016/S0140-6736(11)60438-8
BACKGROUND: The Xpert MTB/RIF test (Cepheid, Sunnyvale, CA, USA) can detect tuberculosis and its multidrug-resistant form with very high sensitivity and specificity in controlled studies, but no performance data exist from district and subdistrict health facilities in tuberculosis-endemic countries. We aimed to assess operational feasibility, accuracy, and effectiveness of implementation in such settings. METHODS: We assessed adults (≥18 years) with suspected tuberculosis or multidrug-resistant tuberculosis consecutively presenting with cough lasting at least 2 weeks to urban health centres in South Africa, Peru, and India, drug-resistance screening facilities in Azerbaijan and the Philippines, and an emergency room in Uganda. Patients were excluded from the main analyses if their second sputum sample was collected more than 1 week after the first sample, or if no valid reference standard or MTB/RIF test was available. We compared one-off direct MTB/RIF testing in nine microscopy laboratories adjacent to study sites with 2-3 sputum smears and 1-3 cultures, dependent on site, and drug-susceptibility testing. We assessed indicators of robustness including indeterminate rate and between-site performance, and compared time to detection, reporting, and treatment, and patient dropouts for the techniques used. FINDINGS: We enrolled 6648 participants between Aug 11, 2009, and June 26, 2010. One-off MTB/RIF testing detected 933 (90·3%) of 1033 culture-confirmed cases of tuberculosis, compared with 699 (67·1%) of 1041 for microscopy. MTB/RIF test sensitivity was 76·9% in smear-negative, culture-positive patients (296 of 385 samples), and 99·0% specific (2846 of 2876 non-tuberculosis samples). MTB/RIF test sensitivity for rifampicin resistance was 94·4% (236 of 250) and specificity was 98·3% (796 of 810). Unlike microscopy, MTB/RIF test sensitivity was not significantly lower in patients with HIV co-infection. Median time to detection of tuberculosis for the MTB/RIF test was 0 days (IQR 0-1), compared with 1 day (0-1) for microscopy, 30 days (23-43) for solid culture, and 16 days (13-21) for liquid culture. Median time to detection of resistance was 20 days (10-26) for line-probe assay and 106 days (30-124) for conventional drug-susceptibility testing. Use of the MTB/RIF test reduced median time to treatment for smear-negative tuberculosis from 56 days (39-81) to 5 days (2-8). The indeterminate rate of MTB/RIF testing was 2·4% (126 of 5321 samples) compared with 4·6% (441 of 9690) for cultures. INTERPRETATION: The MTB/RIF test can effectively be used in low-resource settings to simplify patients' access to early and accurate diagnosis, thereby potentially decreasing morbidity associated with diagnostic delay, dropout and mistreatment. FUNDING: Foundation for Innovative New Diagnostics, Bill & Melinda Gates Foundation, European and Developing Countries Clinical Trials Partnership (TA2007.40200.009), Wellcome Trust (085251/B/08/Z), and UK Department for International Development.
Journal Article > ResearchFull Text
Public Health Action. 2015 June 21; Volume 5 (Issue 2); 140-146.; DOI:10.5588/pha.15.0001
Sikhondze W, Dlamini T, Khumalo D, Maphalala G, Dlamini SV, et al.
Public Health Action. 2015 June 21; Volume 5 (Issue 2); 140-146.; DOI:10.5588/pha.15.0001
SETTING
All 19 public health laboratories in Swaziland that had Xpert(®) MTB/RIF machines installed as part of a countrywide roll-out between June 2011 and June 2014.
OBJECTIVE
To evaluate the utilisation and functionality of Xpert from 2011 to mid-2014.
DESIGN
Descriptive study of Xpert implementation using routinely collected data.
RESULTS
Of 48 829 Xpert tests conducted, 93% were successful: 14% detected Mycobacterium tuberculosis and 12% showed rifampicin resistance. The most common cause of unsuccessful tests was an 'Error' result (62%). Similar findings were obtained in government-supported and partner-supported laboratories. Annual utilisation of Xpert improved from 51% of maximum capacity in 2011 and 2012 to 74% in 2013 and 2014. A monitoring and supervision exercise of all Xpert testing sites in 2014 showed a generally good performance, with over 50% of laboratories achieving a ⩾80% score on most components. However, poor scores were obtained with equipment use and maintenance (6% achieving a score of ⩾80%), internal audit (19% achieving a score of ⩾80%) and process control (25% achieving a score of ⩾80%).
CONCLUSION
Countrywide roll-out of Xpert in Swaziland has been successful, although operational issues have been identified and need to be resolved.
All 19 public health laboratories in Swaziland that had Xpert(®) MTB/RIF machines installed as part of a countrywide roll-out between June 2011 and June 2014.
OBJECTIVE
To evaluate the utilisation and functionality of Xpert from 2011 to mid-2014.
DESIGN
Descriptive study of Xpert implementation using routinely collected data.
RESULTS
Of 48 829 Xpert tests conducted, 93% were successful: 14% detected Mycobacterium tuberculosis and 12% showed rifampicin resistance. The most common cause of unsuccessful tests was an 'Error' result (62%). Similar findings were obtained in government-supported and partner-supported laboratories. Annual utilisation of Xpert improved from 51% of maximum capacity in 2011 and 2012 to 74% in 2013 and 2014. A monitoring and supervision exercise of all Xpert testing sites in 2014 showed a generally good performance, with over 50% of laboratories achieving a ⩾80% score on most components. However, poor scores were obtained with equipment use and maintenance (6% achieving a score of ⩾80%), internal audit (19% achieving a score of ⩾80%) and process control (25% achieving a score of ⩾80%).
CONCLUSION
Countrywide roll-out of Xpert in Swaziland has been successful, although operational issues have been identified and need to be resolved.