New standards on sensitivity testing
1: University Paris Cité
Antituberculous sensitivity testing was set as soon as antituberculous drugs were discovered because patients relapsing from streptomycin therapy were needed to be diagnosed wether they were infected with a Mycobacterium tuberculosis isolate with acquired streptomycin-resistance (R) (need to use another drug) or if the isolate remained streptomycin-susceptible (S) (can be retreated with streptomycin). At this time tuberculose was endemic over the world, so medical researchers and physicians invented and set up, in each country, a suitable method able to distinguish between R and S. This results in many different protocols used today without global standardization. Normative committees, such as CLSI and EUCAST, as well as WHO that is responsible for the elimination of tuberculosis, are trying to harmonize the way clinical microbiology laboratories are testing M. tuberculosis sensitivity to antituberculous drugs. Because new drugs were discovered (bedaquiline, delamanid and pretomanid) or brought up (fluroquinolones, linezolid, clofazimine) to the tuberculosis field, some standardization is needed in order to compare the in vitro activity of all these new compounds, and to screen for resistant isolates, which could be transmitted not only to the nearby population but also to the all world inhabitants. Although these standardization efforts are not new, this time it should work since this is worthwhile to speak the same language when fighting against an ennemy like tuberculosis. Of course industrials, able to provide robust and cheap commercial kits, and regulation bodies, able to bring together different countries and public health authorities, should help to follow the new standards.