NEW YORK – The World Health Organization on Wednesday issued a new standard for countries implementing rapid diagnostics to detect tuberculosis. The guidelines are the first-ever WHO has issued for rapid TB testing.
The document, called the "WHO standard: Universal Access to Rapid Tuberculosis Diagnostics," comprises 12 benchmarks to achieve universal access to WHO-recommended rapid diagnostics, or WRDs.
WRDs are highly accurate, cost-effective, reduce the time to treatment initiation, and impact patient outcomes, the WHO said in a statement. To achieve universal access to WRDs, the standard recommends increasing rates of bacteriologically confirmed TB and detection of drug resistance, and reducing the time to diagnosis.
The benchmarks aim to increase the number of people with presumptive TB in care and increase access to testing. For all facilities, the use of a WRD is required as an initial diagnostic test for all patients.
"Enabling universal access to rapid TB diagnostics recommended by WHO will ensure that people with TB get on the pathway to cure faster, cutting transmission and the impact of this debilitating disease on their lives and families," said Tereza Kasaeva, director of WHO's Global TB Program.
"We encourage countries to rapidly implement the standard and call for investments and support from partners, donors, and civil society to ensure universal access to WRDs," Kasaeva added.
The WHO's 2021 guidance recommends nucleic acid amplification or biomarker-based testing for TB, and currently guides countries to select from tests grouped by complexity rather than its prior product-specific recommendations.
The tests recommended for the initial detection of TB include Cepheid's Xpert MTB/RIF Ultra and Xpert MTB/RIF, MolBio Diagnostics' Truenat MTB, MTB Plus, and MTB-RIF Dx tests, Eiken Chemical's loop-mediated isothermal amplification TB-LAMP, Becton Dickinson's BD MAX MDR-TB assay, Bruker/Hain Lifescience's Hain FluoroType MTBDR assay, Roche's Cobas MTB and MTB-RIF/INH assays, and Abbott Laboratories' Abbott RealTime MTB and MTB RIF/INH assays as well as its Alere Determine TB LAM Ag biomarker-based assay.
If a primary TB assay does not also detect resistance, WHO also recommends follow-on assays for detection of resistance to certain treatments. The products in this category are the Bruker/Hain Lifescience GenoType MTBDRplus and GenoType MTBDRsl, Nipro's NTM+MDRTB Detection Kit and Genoscholar PZA-TB II, and Cepheid's Xpert MTB/XDR.
The WHO noted that although its End TB Strategy calls for all TB patients to be initially tested with a WRD by 2025, only 38 percent of patients received a WRD as an initial test in 2021, and access to diagnostics was identified as a critical underlying issue. A significant consequence of the insufficient use of WRDs is the large gap in detecting resistance to anti-TB drugs, the WHO said.