Setting: A tertiary referral centre in Seoul, South Korea.
Objective: To investigate the effect of moxifloxacin (MFX) susceptibility and later-generation fluoroquinolone (FQ) use on the treatment outcomes of ofloxacin (OFX) resistant multidrug-resistant tuberculosis (MDR-TB).
Design: Of 223 patients diagnosed with MDR-TB between January 2006 and December 2012, 70 (31.4%) patients with OFX-resistant MDR-TB were enrolled in this retrospective cohort study. Their treatment outcomes were analysed.
Results: The mean age (standard deviation) of the 70 patients was 40.6 (12.9) years; 43 (61.4%) were male and 26 (37.1%) had extensively drug-resistant TB. Of the 70 patients, 22 (31.4%) had MFX-susceptible TB, while the remaining 48 (68.6%) were MFX-resistant. The MFX-susceptible and -resistant groups were comparable in terms of baseline characteristics (including age, sex and radiological severity), and respectively 90.9% (20/22) and 70.8% (34/48) were treated with later-generation FQ-containing regimens (P = 0.074; mainly MFX [40/54, 74.1%]). Treatment success was achieved in 72.7% (16/22) of the MFX-susceptible patients and in 41.7% (20/48) of the MFX-resistant patients (P = 0.021). Treatment failure was significantly higher in the MFX-resistant group (41.7% [20/48] vs. 9.1% [2/22]; P = 0.006).
Conclusion: Patients with OFX-resistant MDR-TB had significantly better treatment outcomes when susceptible to MFX. This probably reflects the effect of later-generation FQ treatment.