Risk factors for linezolid-associated thrombocytopenia and negative effect of carbapenem combination

Linezolid is a synthetic antimicrobial agent with a broad spectrum of activity against virtually all Gram-positive bacteria. Although linezolid is generally well tolerated, the prolonged use of linezolid can lead to myelosuppression, including neutropenia, thrombocytopenia, and anemia. The aim of this study was investigating the risk factors for thrombocytopenia in patients who received linezolid therapy.

This retrospective study was performed on patients who received linezolid therapy between July 2007 and December 2017. Thrombocytopenia was defined as either a platelets count of < 100×109/L or a 25% reduction from the baseline platelet count.

A total of 371 patients, (198 (53%) male and 173(47%) female were included into the study. Mean duration of therapy was 12.81 ± 5.19 days. Linezolid-induced thrombocytopenia was detected in a total of 111 patients. Using the univariate analysis advanced sex, serum urea concentration, baseline platelet level and low eGFR value were found to be risk factors for linezolid associated thrombocytopenia (p < 0.05). According to a multivariate analysis, patients undergoing carbapenem treatment combination therapy (p = 0.003) and with a baseline platelet level of < 200×109/L (p = 0.00) were found to have a high risk of developing thrombocytopenia.

Several factors may influence of linezolid associated thrombocytopenia. Platelet count should be monitored during therapy and thrombocytopenia should be kept in mind in patients with baseline platelet level of < 200×109/L, low eGFR, linezolid-carbapenem combination therapy.