Diagnosing pulmonary tuberculosis (TB) remains difficult, particularly in countries with limited resources. The WHO estimates that around a third of TB cases are not diagnosed due to a number of barriers such as:
- The geographical distance between inhabitants of rural areas and health centers, limiting access to high-quality consultations and additional examinations,
- The diagnostic tests currently in use, as well as having suboptimal performance, often require an energy source for storage or use and a supply chain that is complex to set up and sustain,
- Sputum, which is the main sample used for screening or diagnosing TB, is difficult to obtain from some sections of the population, especially children, people living with HIV and asymptomatic cases.
The Mérieux Foundation has set up a collaboration with the team working under Dr Jérôme Nigou at the Institute of Pharmacology and Structural Biology (IPBS), a CNRS research center at the University of Toulouse, which has recently presented and published some highly promising preliminary results on a biomarker found in the air, which will enable the diagnosis of pulmonary TB.
The EBC-LAM project sets out to improve the diagnosis of pulmonary TB in countries with limited resources using an innovative, non-invasive method that fulfills the WHO’s requirements, using a rapid test to analyze a sample of air.
This test is based on the identification of a component of the mycobacterial membrane (lipoarabinomannan or LAM) using a sample of exhaled breath condensate (EBC) or aerosol. This method offers several advantages:
- The sample is extremely easy and inexpensive to collect, which means that the test can be carried out by unqualified or low-qualified staff, and it does not require any specific infrastructure.
- The test does not require any logistics circuit or storage conditions with a controlled temperature.
- The test result is obtained within the hour, which means that patients can be looked after quickly without having to return to the health center.
This triage test will enable national programs for fighting the disease to achieve economies of scale by offering confirmation tests (more expensive and requiring more infrastructure and qualified staff) only to people who really need them.
With this project, the Mérieux Foundation and its partners aim to confirm the relevance of this new method as a triage tool for the diagnosis of TB on a larger scale. A clinical study for validating the concept has been designed and introduced with the support of Dr Nigou’s team, the International Center for Diarrheal Disease Research in Bangladesh (icddr,b), a member of the Mérieux Foundation’s GABRIEL research network, and FINDdx (affiliated with the WHO).
- IPBS-CNRS: Dr Jérôme Nigou
- Icddr,b, Bangladesh