Impact of Anti-Tuberculosis Drug Use on Treatment Outcomes in Patients with Pulmonary Fluoroquinolone-Resistant Multidrug-Resistant Tuberculosis: A Nationwide Retrospective Cohort Study with Propensity Score Matching

Abstract

Background: Effective treatment of fluoroquinolone-resistant multidrug-resistant tuberculosis (FQr-MDR-TB) is difficult because of the limited number of available core anti-TB drugs and high rates of resistance to anti-TB drugs other than FQs. However, few studies have examined anti-TB drugs that are effective in treating patients with FQr-MDR-TB in a real-world setting.Methods: The impact of anti-TB drug use on treatment outcomes in patients with pulmonary FQr-MDR-TB was retrospectively evaluated using a nationwide integrated TB database (Korean Tuberculosis and Post-Tuberculosis). Data from 2011 to 2017 were included.Results: The study population consisted of 1,082 patients with FQr-MDR-TB. The overall treatment outcomes were as follows: treatment success (69.7%), death (13.7%), lost to follow-up or not evaluated (12.8%), and treatment failure (3.9%). On a propensity-score-matched multivariate logistic regression analysis, the use of bedaquiline (BDQ), linezolid (LZD), levofloxacin (LFX), cycloserine (CS), ethambutol (EMB), pyrazinamide, kanamycin (KM), prothionamide (PTO), and para-aminosalicylic acid against susceptible strains increased the treatment success rate (vs. unfavorable outcomes). The use of LFX, CS, EMB, and PTO against susceptible strains decreased the mortality (vs. treatment success).Conclusion: A therapeutic regimen guided by drug-susceptibility testing can improve the treatment of patients with pulmonary FQr-MDR-TB. In addition to core anti-TB drugs, such as BDQ and LZD, treatment of susceptible strains with later-generation FQs and KM may be beneficial for FQr-MDR-TB patients with limited treatment options.

Treatment Outcomes of Fluoroquinolone-Resistant Multidrug-Resistant Tuberculosis: An Implication for Delamanid

“…Those who were previously treated with antitubercular drugs and with lung cavities were risk factors for pre-XDR TB and XDR-TB [ 4 ]. As reported by Choi et al [ 1 ], more than 60% of DR-TB patients had a history of TB treatment.…”

“…We greatly appreciated a study by Choi et al [ 1 ] reporting treatment outcomes in pre-extensively drug-resistant tuberculosis (pre-XDR-TB) patients (fluoroquinolone resistance) with propensity score matching. The data of pre-XDR-TB patients were collected retrospectively over 7 years [ 1 ]. Drug-resistant tuberculosis (DR-TB) is one of the most infectious diseases, with a low rate of treatment success and high mortality rates.…”

“…However, the use of delamanid was not associated with treatment success. Overall, the treatment success rate was 69.7% among the pre-XDR TB patients [ 1 ]. Our previous study reported that in DR-TB patients who received regimens containing bedaquiline and delamanid, favorable outcomes (treatment success and treatment completion) at the end of treatment ranged from 67.5% to 91.4% [ 9 ].…”

Treatment Outcomes of Fluoroquinolone- Resistant Multidrug-Resistant Tuberculosis: An Implication for Delamanid - Authors’ Reply

“…In our study, the use of DLM did not significantly affect treatment success or reduce mortality in patients with FQr-MDR-TB [ 1 ]. This apparent lack of efficacy might be more attributable to the greater severity of TB in patients treated with DLM than to the reduced effectiveness of the drug itself.…”

“…We express our gratitude to Putra and Purnamasari for their comments on our article, which explored the impact of anti-tuberculosis (TB) drug use on treatment outcomes in patients with pulmonary fluoroquinolone-resistant multidrug-resistant tuberculosis (FQr-MDR-TB) [ 1 ]. Fluoroquinolones (FQs) have been core drugs in the treatment of MDR-TB for many years due to their superior bactericidal and sterilizing properties and their role in preventing resistance to other anti-TB drugs [ 2 ].…”