Excerpt

Earlier and improved tuberculosis (TB) case detection - including smear-negative disease, often associated with HIV co-infection - as well as expanded capacity to diagnose multidrug-resistant tuberculosis (MDR-TB) are global priorities for TB control. Conventional laboratory methods are slow and cumbersome and novel technologies for rapid detection are therefore the focus of TB research and development. With support from NIH, the Foundation for Innovative New Diagnostics (FIND) has partnered with Cepheid, Inc. (Sunnyvale, CA) and the University of Medicine and Dentistry of New Jersey (UMDNJ, Newark, NY) to develop a TB-specific automated, cartridge-based nucleic amplification assay (Xpert MTB/RIF) based on the GeneXpert multi-disease platform, currently unique in its simplification of molecular testing with fully integrated and automated sample preparation, amplification and detection required for real-time polymerase chain reaction. Xpert MTB/RIF detects M. tuberculosis as well as rifampicin resistance-conferring mutations directly from sputum, in an assay providing results within two hours. Data from published papers, large multi-centre laboratory validation and demonstration studies coordinated by FIND, and unpublished data investigator-driven, single-centre studies were recently reviewed by WHO with the aim to develop policy guidance on Xpert MTB/RIF use.

Contents

• Executive summary
• Acknowledgements
• Declarations of Interest
• 1. Background
• 2. Methods
  • 2.1 Evidence synthesis
  • 2.2 Decision-making during the Expert Group meeting
• 3. Scope of the policy guidance
• 4. Evidence base for policy formulation
  • 4.1 Analytic studies
  • 4.2 Multi-centre clinical validation studies
  • 4.3 Demonstration studies
  • 4.4 Unpublished single-centre evaluation studies
  • 4.5 Operational and programmatic aspects
  • 4.6 Cost-effectiveness modeling
• 5. Policy recommendations
• 6. Implementation considerations
• 7. Research implications
• 8. Plans for supporting roll-out of Xpert MTB/RIF
• 9 References
• 10 GRADE tables
• Annexes
  • ANNEX 1 Xpert MTB/RIF Expert Group Members
  • ANNEX 2 WHO staff members
  • ANNEX 3 STAG-TB members

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