In vitro susceptibility testing and totally drug-resistant tuberculosis

To the Editor:

We find the article by Migliori et al. [1], on extensively drug-resistant tuberculosis (XDR-TB), very informative and would like to commend them for the excellent meta-analysis. Without any doubt, XDR-TB is an extensive global problem; the use of the lower susceptibility breaking points that we recently suggested [2] mean that the burden of XDR-TB could be even higher. Although there are recent reports of “totally drug-resistant (TDR)” TB, the World Health Organization does not recognise this term [3]. There is already a social stigma attached to having TB in many parts …