Efficacy and Tolerability of Linezolid for Treatment of Infectious Spondylitis

Background/Aims: Infectious spondylitis requires long-term antibiotic treatment; however, the use of intravenous antibiotics during this period has high social and monetary costs due to hospitalization. Linezolid has high oral bioavailability and is not affected by changes in renal or hepatic function. We investigated the clinical and microbiological effects of linezolid in infectious spondylitis caused by beta-lactam resistant gram-positive bacteria. Methods: Clinical data from patients who were treated with linezolid for at least four weeks were collected retrospectively from electronic medical records at the Seoul National University Hospital, Seoul National University Bundang Hospital, and Boramae Medical Center from 2006 to 2016. Results: Twenty Korean patients were treated with linezolid for at least four weeks during the study period. Of these, 14 patients were cured, four failed, and two cases of mortality occurred due to other causes than infectious spondylitis. Ten of 13 patients who had previously been assessed as vancomycin treatment failure were cured by linezolid. Bacteremia occurred in 14 patients, and 10 of these showed persistent bacteremia at the time of linezolid administration. Eight of these cases of persistent bacteremia were cured by linezolid. Median duration of linezolid treatment was 40.5 days (28-90 days). Severe cytopenia (grade II or more of National Cancer Institute criteria) was the most common adverse event, with incidences of 11.11% for neutropenia, 12.96% for anemia, and 20.37% for thrombocytopenia. Conclusions: Linezolid can be used as an effective antibiotic agent in patients with infectious spondylitis, especially when treatment failure of the first-line treatment is expected. (