Tuberculosis (TB)

TB diagnostics and laboratory strengthening


Policy

Upcoming Guideline Development Group Meetings

When adequate data on the performance of new diagnostics are available, the WHO Global TB Programme follows a systematic process for policy development, involving synthesis of the available evidence through systematic reviews, assessment of the evidence by an external Guideline Development Group using the GRADE approach (http://www.gradeworkinggroup.org), and development of policy guidance for dissemination to Member States and other stakeholders.

Urine Lipoarabinomannan (LAM) - 1 June 2015

Tests based on the detection of mycobacterial lipoarabinomannan (LAM) antigen in urine have emerged as potential point-of-care tests for TB. Owing to suboptimal sensitivity, the urinary lateral-flow LAM (LF-LAM) assays are unsuitable as general screening tests for TB. However, unlike traditional diagnostic methods, they demonstrate improved sensitivity in HIV-TB co-infection which further increases with low CD4 counts. The urinary LF-LAM strip-test (Determine®-TB, Alere, USA) potentially can be used as a rule-in test for TB in patients with advanced HIV-induced immunosuppression, and facilitate the early initiation of anti-TB treatment in them.

The objectives and proposed membership of the Guideline Development Group meeting to be convened on 1 June 2015 are described herein:

Loop-mediated isothermal amplification (TB-LAMP) - 2 June 2015

The TB-LAMP technology (Eiken Chemical Co., Ltd) was initially evaluated by WHO in May 2013. The assay has potential as a rapid TB diagnostic tool, but the body of evidence presented in 2013 was insufficient for the Guideline Development Group to make a recommendation either in favour of, or against the use of TB-LAMP as a replacement test for sputum smear microscopy. Since 2013, additional demonstration studies have been conducted, generating data that may address the concerns raised by the previous Guideline Development Group.

The objectives and proposed membership of the Guideline Development Group to be convened on 2 June 2015 are described herein:

Framework for implementing TB diagnostics (updated)





Xpert MTB/RIF



Biosafety




Line probe assays (LPA)




Microscopy


Culture and drug susceptibility testing (DST)


Interferon-gamma release assays (IGRAs)



Commercial serodiagnostic tests

Commercial serodiagnostic tests for diagnosis of tuberculosis: policy statement




Loop-mediated Isothermal Amplification (LAMP) assay





Definitions and reporting




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