Background/Aims To compare the effect of levofloxacin and moxifloxacin about treatment results among individuals with multidrug-resistant tuberculosis (MDR-TB). group experienced a significantly higher number of resistant medicines (< 0.001) and a higher incidence of resistance to ofloxacin (= 0.005) in the drug sensitivity test. The treatment success rate was 78.9% in the levofloxacin group and 83.3% in the moxifloxacin group (= 0.42). Adverse reactions occurred at related rates in the organizations (= 0.44). Individuals in the moxifloxacin group were not more likely to have treatment success than those in the levofloxacin group (modified odds percentage, 0.76; 95% confidence interval, 0.24 to 2.43; = 0.65). Conclusions Both levofloxacin and moxifloxacin showed equal effectiveness for treating MDR-TB. resistance to at least isoniazid and rifampicins, is definitely a growing health concern. An estimated 440,000 (95% confidence interval [CI], 390,000 to 510,000) instances of MDR-TB, which is 3.6% of all incident TB cases, emerge each year, causing 150,000 deaths worldwide [1]. Only a few effective second-line anti-TB drugs are available, and those at the forefront are fluoroquinolones (FQNs). FQNs show an encouraging pharmacokinetic profile for treating TB [2-5], and current guidelines for managing MDR-TB recommend that all patients be treated with FQNs if the strain is usually susceptible or if the agent is usually thought to have efficacy [5]. In particular, the minimum inhibitory concentrations of moxifloxacin are lower than those of levofloxacin 477845-12-8 manufacture [3,6], and moxifloxacin exhibits activity [6], and early bactericidal activity [7] that is comparable to that of isoniazid. Although several studies [8-11] have compared levofloxacin with other FQNs, such as ciprofloxacin or ofloxacin, studies comparing levofloxacin and moxifloxacin are lacking. This led us to conduct a retrospective case-control study of patients with MDR-TB who were treated with either levofloxacin or moxifloxacin and to compare their treatment outcomes. METHODS Study populace Patients 477845-12-8 manufacture with MDR-TB 477845-12-8 manufacture receiving either levofloxacin or moxifloxacin along with other second-line anti-TB medication from January 2002 through December 2008 were included. Patients were treated in one of three hospitals affiliated with Seoul National University College of Medicine in Korea: Seoul National University Hospital, Seoul Metropolitan Government Seoul National University Boramae Medical Center, or Seoul National University Bundang Hospital. was recognized by sputum culture, and all patients showed resistance to at least isoniazid and rifampicins in drug-susceptibility screening. Patients < 18 years of age, those treated with both levofloxacin and moxifloxacin for TB, and patients who received less than 3 months of levofloxacin or moxifloxacin were excluded from analysis. This study was approved by the ethics review committees of all three hospitals. Previous studies by our group were also based on part of this populace of patients with MDR-TB [12-15]. The choice of FQNs was based on the Gfap preference of the attending physician, according to the drug-susceptibility test results. The other combined drugs included aminoglycosides, prothionamide, cycloserine, pyrazinamide, rifabutin, ethambutol, test for continuous variables. To understand the impact of choice between the levofloxacin and moxifloxacin group on treatment outcomes, we compared selected clinical variables between treatment success and failure through a univariate comparison and subsequent multiple logistic regression. All statistical analyses were performed with SPSS version 11.0 (SPSS Inc., Chicago, IL, USA). RESULTS Patient demographic and clinical characteristics 477845-12-8 manufacture Between January 2002 and December 2005, 171 patients received either levofloxacin or moxifloxacin to treat MDR-TB. In total, 123 patients (71.9%) were treated with levofloxacin and 48 patients (28.1%) received moxifloxacin. One-hundred nine patients were from Seoul National University Hospital, 26 were from Seoul Metropolitan Government Seoul National University Boramae Medical Center, and 36 patients were from Seoul National University Bundang Hospital. Except for one 38-year-old Chinese man, all 170 patients were Korean. All subjects experienced radiographic and bacteriologic evidence of pulmonary TB, and 20.5% had combined extrapulmonary involvement. The most common extrapulmonary TB.