Linezolid for drug-susceptible tuberculosis

Abstract

We would like to thank Jung-Kyu Lee and colleagues1Lee J-K Lee JY Kim DK et al.Substitution of ethambutol with linezolid during the intensive phase of treatment of pulmonary tuberculosis: a prospective, multicentre, randomised, open-label, phase 2 trial.Lancet Infect Dis. 2019; 19: 46-55Summary Full Text Full Text PDF PubMed Scopus (24) Google Scholar for the impressive work they have executed. This prospective, multicentre, randomised trial reports the short-term treatment outcomes of linezolid compared with standard treatment in drug-susceptible tuberculosis. However, we would like to point out several important aspects regarding the time to culture conversion and culture conversion rates after 8 weeks of treatment in patients with cavitary and non-cavitary tuberculosis. Lee and colleagues randomly assigned 428 patients and detected cavitary lesions in 159 (40%) patients. It is regrettable that the authors did not analyse patients with cavitary lesions for the primary outcome. Treatment of cavitary tuberculosis is troublesome since the starting bacilli burden is high and the time to culture conversion is longer than with non-cavitary tuberculosis.2Perrin FMR Woodward N Phillips PPJ et al.Radiological cavitation, sputum mycobacterial load and treatment response in pulmonary tuberculosis.Int J Tuberc Lung Dis. 2010; 14: 1596-1602PubMed Google Scholar, 3Matsuoka S Uchiyama K Shima H et al.Relationship between CT findings of pulmonary tuberculosis and the number of acid-fast bacilli on sputum smears.Clin Imaging. 2004; 28: 119-123Summary Full Text Full Text PDF PubMed Scopus (64) Google Scholar, 4Palaci M Dietze R Hadad DJ et al.Cavitary disease and quantitative sputum bacillary load in cases of pulmonary tuberculosis.J Clin Microbiol. 2007; 45: 4064-4066Crossref PubMed Scopus (119) Google Scholar In one study,5Telzak EE Fazal BA Pollard CL Turett GS Justman JE Blum S Factors influencing time to sputum conversion among patients with smear-positive pulmonary tuberculosis.Clin Infect Dis. 1997; 25: 666-670Crossref PubMed Scopus (115) Google Scholar the presence of cavitary lesions was an independent risk factor for the prolonged time to culture conversion. Su and colleagues6Su WJ Feng JY Chiu YC Huang SF Lee YC Role of 2-month sputum smears in predicting culture conversion in pulmonary tuberculosis.Eur Respir J. 2011; 37: 376-383Crossref PubMed Scopus (34) Google Scholar showed the association of directly observed therapy and non-cavitary disease with sputum culture conversion rates in multivariate analysis. We would like to encourage a subgroup analysis of the patients with cavitary lesions to find out whether the time to culture negativity and the proportion of patients with sputum culture conversion differs between the study groups. We believe this issue is of importance regarding infection prevention and control measures in the hospital and the community. Higher and faster culture conversion rates would affect the duration of patient isolation and would affect patient-to-patient and patient-to-health-care worker transmission of tuberculosis. We declare no competing interests. We express our gratitude to our chief of department Volkan Korten for his motivation and encouragement to submit this Correspondence. Substitution of ethambutol with linezolid during the intensive phase of treatment of pulmonary tuberculosis: a prospective, multicentre, randomised, open-label, phase 2 trialHigher rates of culture conversion at 8 weeks of treatment with short-term use of linezolid were not observed. However, safety analyses and the resistance profile suggested the potential role of linezolid in shortening of treatment for drug-susceptible tuberculosis. Full-Text PDF Linezolid for drug-susceptible tuberculosisWe question why linezolid would be included in a regimen for drug-susceptible tuberculosis, as described by Jung-Kyu Lee and colleagues,1 given its known toxicity profile. Regardless of the underlying premise, we have substantial concerns about the manner in which the data have been analysed and presented, and about the conclusions that have been drawn. Full-Text PDF Linezolid for drug-susceptible tuberculosisWe appreciate the interest in and comments on our trial by Hüseyin Bilgin and colleagues1 and Saiam Ahmed and colleagues,2 which was done to assess the substitution of ethambutol with linezolid during the intensive phase of treatment of pulmonary tuberculosis.3 Several concerns were raised regarding our analysis of the results. Full-Text PDF