CORRESPONDENCE

Fluoroquinolones: are they essential to treat multidrug-resistant tuberculosis? To the Editors: We read with interest the excellent letter by HOLTZ and CEGIELSKI [1] contributing to the current discussion on extensively drug-resistant (XDR)-tuberculosis (TB). Several publications have already demonstrated that resistance to fluoroquinolones (FQ) is independently associated with poor outcome and/or that the possibility of including FQ in regimens improves treatment outcomes of multidrug-resistant (MDR)-TB cases [2–4]. This happened before the (recent) description of XDR-TB [1, 5]. We do not know how many of the patients with MDR-TB strains were, in fact, infected with XDR Mycobacterium tuberculosis. We wanted to establish the role of the different XDR-definin