Fluoroquinolone antibiotics are an important part of regimens for multidrug-resistant tuberculosis (TB). Exposure to these agents prior to a TB diagnosis (for a different bacterial infection), however, may provoke drug resistance in Mycobacterium tuberculosis.
To assess whether the specific type of fluoroquinolone used before a TB diagnosis impacts the development of drug-resistant TB, Yuri van der Heijden, M.D., and colleagues performed a case-control study of TB patients reported to the Tennessee Department of Health from 2002-2009. Cases had fluoroquinolone-resistant M. tuberculosis isolates; controls had drug-susceptible isolates. The investigators found that the duration of exposure to newer fluoroquinolones (levofloxacin, moxifloxacin, gatifloxacin) – but not to older drugs (ciprofloxacin, ofloxacin) – was associated with the drug-sensitivity of M. tuberculosis and the frequency of drug-resistant mutations.
The findings, reported in the September International Journal of Antimicrobial Agents, support caution in prescribing newer fluoroquinolones to patients with TB risk factors – to avoid jeopardizing the use of these agents against TB.
This research was supported by National Institutes of Health grants AI063200, AI065298 and AI007474.
Send suggestions for articles to highlight in Aliquots and any other feedback about the column to aliquots@vanderbilt.edu