[Diagnosis of tuberculosis in developing countries: new perspectives]

Tuberculosis (TB) is still a major public health problem in the world despite the ambitious goals of the DOTS strategy, i.e., detection of 70% of new cases and successfully treatment of at least 85% of those cases. One of the main reasons for this relative failure is lack of a sensitive method for reliable diagnosis particularly in HIV-positive patients. Development of new diagnostic tools is a top priority in the WHO's "Global plan to stop TB, 2006-2015". Numerous avenues of research have been proposed including development of immunological tests to detect antigens and antibodies, cutaneous tests, respiratory tests, improved solid or liquid culture techniques, alternatives to culture techniques, molecular biology techniques, etc. Some of these techniques will require long-term development and others will probably never be suitable for routine diagnosis. However a few innovations such as optimization of direct microscopic examination using new lower-priced fluorescence microscopes are ready for rapid deployment. Another promising area of research involves immunoenzymatic testing on urine samples. In any event clinical trials will be necessary to demonstrate the efficacy of these new diagnostic tools. These trials must be conducted and controlled under field conditions in the geographical zones where they will be used, i.e. in low-income countries with high incidences of TB.