Diagnosis

Abbott Molecular diagnostic solution for tuberculosis (TB) has two nucleic acid amplification tests (NAATs), one for detection of Mycobacterium tuberculosis complex (MTBC) (RealTime MTB test) and one for detection of resistance to both rifampicin (RIF) and isoniazid (INH) (RealTime MTB RIF/INH) (1). TB detection is based on the IS6110 genetic element and the pab gene targets.

The political declaration at the first United Nations (UN) high-level meeting on tuberculosis (TB) held on 26 September 2018 included commitments by Member States to four new global targets ³ , which were subsequently renewed at the second UN high-level meeting on TB on 22 September 2023⁴ . One of these targets is that at least 90 per cent of the estimated number of people who develop TB are reached with quality-assured diagnosis and treatment in the 5-year period 2023–2027³ .

The 10 main areas in implementing a new test are listed in Box 4.1. The following sections describe the steps within each of the 10 areas.

QA: quality assurance; QC: quality control; TB: tuberculosis.

As with any diagnostic test, correct technique in administration and reading of the test is essential for accurate, reproducible and valid test results. Therefore, personnel require initial training, mentoring and ongoing supervision to maintain quality (42). Training for reading of tuberculin reactions is ideally done at a large centre where large numbers of people receive TB infection skin tests regularly. In this way, in a relatively short amount of time, trainees can practise the reading of indurations of different sizes and consistency.

To avoid barriers or delays created by TB infection testing, and to minimize associated losses in the TB infection care cascade, an integrated person-centred care model is preferred for TB infection diagnosis and treatment. Here, “integrated” means carrying out screening for TB disease and testing for TB infection in parallel, and “person-centred care” means coordination of multiple care activities during the same visits.

The recommendations included in these consolidated policy guidelines on tuberculosis (TB) are the result of a collaborative effort among professionals from a range of specialities. The World Health Organization (WHO) is grateful for their time and support.

TB antigen-based skin tests (TBSTs) for the diagnosis of TB infection

GDG meeting on use of TBSTs for the diagnosis of TB infection, Geneva, Switzerland, 31 January–3 February 2022

Guideline Development Group