Effect of a serum lactate monitoring recommendation policy on patients treated with linezolid

Lactic acidosis is one of the most fatal adverse effects of linezolid, an antibiotic used to treat serious infections caused by antibiotic-resistant bacteria. However, the measures to prevent lactic acidosis have not been well established. We performed a retrospective study to analyze the impact of applying a serum lactate monitoring recommendation policy in patients treated with linezolid. Since September 2011, we have recommended inpatient monitoring of serum lactate levels in patients treated with linezolid at our hospital. Patients were divided into two groups according to whether they were seen during the non-recommendation or recommendation periods. The frequency of serum lactate monitoring, linezolid-induced lactatemia, lactic acidosis, critical illness, and death were compared between the two periods. After September 2011, adherence to the recommendation to monitor serum lactate increased from 6.1% to 60.1%. No difference was observed in the incidence of linezolid-induced lactatemia and lactic acidosis between the two periods. However, there was a significant difference in the incidence of linezolid-induced critical illness between the non-recommendation and recommendation periods (3 vs 0 cases, P = .044). In patients treated with linezolid, serum lactate monitoring led to early detection of lactatemia, thus enabling rapid rescue. We recommend regular monitoring of serum lactate in all patients treated with linezolid.