Treatment outcome, recurrence and safety of multidrug-resistant TB treated with low-dose linezolid

BACKGROUND: Linezolid (LZD) is a key treatment option for patients with multidrug-resistant/rifampicin-resistant TB (MDR/RR-TB). We investigated the long-term treatment outcomes and safety of MDR/RR-TB treatment using low-dose LZD. METHODS: Medical records of patients with MDR/RR-TB treated with LZD ≥4 weeks between 2004 and 2018 at the Asan Medical Center, Seoul, Republic of Korea, were reviewed. Standard-dose and low-dose LZD groups were defined as patients initially administered LZD ≥600 mg/day or 300 mg/day, respectively. RESULTS: Among 94 patients, 65 were included in the low-dose LZD group; mean age was 43.1 ± 15.6 years, 53 (56.4%) were men and 77 (83.7%) were resistant to fluoroquinolone. The low-dose LZD group showed features of less severe disease, such as limited MDR-TB history and less severe radiological findings. There was no difference in treatment outcomes, relapse and safety between groups. In the low-dose LZD group, 54 (83.1%) succeeded treatment, of whom 48 (88.9%) were followed-up for a median of 38 months; there was no recurrence. Adverse drug reactions were reported in 41 (63.1%); peripheral neuropathy was most frequently reported ( n = 31, 47.7%), while myelosuppression was reported in 12 (18.5%). CONCLUSION: Low-dose LZD in selected patients with less severe disease is both effective in the long-term and safe for the treatment of MDR/RR-TB.