Evaluation of factors associated with the achievement of an optimal teicoplanin trough concentration

Because teicoplanin has a long serum half-life, a longer period of time is needed to achieve a steady-state concentration compared with vancomycin. The administration of an initial loading dose has been recommended to reach an effective teicoplanin serum concentration for the treatment of methicillin-resistant Staphylococcus aureus (MRSA). However, little is known regarding factors that affect teicoplanin concentration. This study aimed to retrospectively determine which factors are associated with achieving an optimal teicoplanin trough level.We analyzed patients with MRSA infections who were treated with teicoplanin intravenously between January 2010 and July 2014. The effect of loading dose administration was evaluated in patients treated with 1,200 mg or 1,600 mg of teicoplanin, respectively.Approximately 32% (31/97) of patients achieved the trough concentration target (≥ 15 µg/mL) on the 3rd or 4th day. Multivariate analysis showed that loading doses and body surface area (BSA) were associated with trough concentration > 15 µg/mL on the 3rd or 4th day. Moreover, patients treated with the 2-day loading dose (1,600 mg group: 800 mg/day on 2 days) promptly achieved a trough concentration > 15 µg/mL on the 3rd or 4th day compared with those receiving a 1-day loading dose (1,200 mg group: 800 mg/day on only 1 day). The receiver operating characteristic curve showed that the optimal cut-off point of estimated glomerular filtration rate (eGFR) was 56 mL/min with 1-day loading dose to achieve a trough concentration target > 15 µg/mL.These results suggested that patients with decreased renal function (eGFR < 56 mL/min) can safely achieve an optimal trough level with the 1-day loading dose. In patients with normal renal function (eGFR ≥ 56 mL/min), administration of a 2-day loading dose may be needed to rapidly achieve a trough concentration ≥ 15 µg/mL. .