Overview

In December 2010, WHO first recommended the use of the Xpert MTB/RIF assay. The WHO’s policy statement was supported by a rapid implementation document, which provided the technical “how-to” and operational considerations for rolling out the use of the assay. An unprecedented uptake of this new technology followed the release of WHO’s policy: by the end of March 2014, more than 2,300 GeneXpert instruments and more than 6 million Xpert MTB/RIF cartridges had been procured in the public sector in 104 countries eligible for concessional prices.

An Expert Group was convened by WHO in May 2013 to review the current body of evidence on use of Xpert MTB/RIF. The resulting recommendations from the Expert Group are included in the WHO Policy update, which widens the recommended use of Xpert MTB/RIF, including for the diagnosis of paediatric TB and on selected specimens for the diagnosis of extrapulmonary TB, and includes an additional recommendation on the use of Xpert MTB/RIF as the initial diagnostic test in all individuals presumed to have pulmonary TB.

The accompanying Xpert MTB/RIF implementation manual has been developed to replace the first edition and takes into consideration the current body of evidence and operational experiences available, in the context of the Policy update.

Contents

• Acknowledgements
• Abbreviations
• 1. Background
• 2. Policy development
  • 2.1 Procedure for developing policies
  • 2.2 Initial policy recommendations and follow up
  • 2.3 Policy update
  • 2.4 Summary of WHO's 2013 policy recommendations
• 3. Evidence base
  • 3.1 Evidence available at the end of 2010
  • 3.2 Evidence base as of February 2013
• 4. Positioning the test and selecting a site
• 5. Testing and managing patients
  • 5.1 Selecting individuals to be tested
  • 5.2 Test performance
  • 5.3 Interpreting results from Xpert MTB/RIF
  • 5.4 Diagnostic algorithms
  • 5.5 Monitoring patients during treatment
  • 5.6 Using Xpert MTB/RIF in drug resistance surveys
  • 5.7 Using Xpert MTB/RIF in TB prevalence surveys
• 6. Case definitions and patient registration
  • 6.1 TB case
  • 6.2 Classification based on type of drug resistance
  • 6.3 Registration of TB cases diagnosed using Xpert MTB/RIF
• 7. Practical considerations
  • 7.1 Operational considerations
  • 7.2 Preferential pricing and eligible countries
  • 7.3 Implementation costs
  • 7.4 Public health impact of Xpert MTB/RIF
• 8. Monitoring and evaluation
  • 8.1 Routine monitoring
  • 8.2 Measuring the impact
• 9. Collaboration and coordination
  • 9.1 Knowledge sharing
  • 9.2 Donors supporting the roll-out of Xpert MTB/RIF
• Annex 1 Countries eligible for preferential pricing on equipment and consumables
• Annex 2 Standard Operating Procedure (SOP) for processing extrapulmonary specimens (CSF, lymph nodes and other tissues) for Xpert MTB/RIF assay

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