Association of the predicted free blood concentration of teicoplanin with the development of renal dysfunction.

Purpose: In clinical practice, teicoplanin (TEIC) is typically administered at a trough concentration of 15-40 µg/mL. TEIC has a protein binding rate of approximately 90%, and its concentration rarely exceeds 40 µg/ml. Nevertheless, an increase in the free blood trough concentration may result in renal dysfunction. However, the relationship between the free blood trough concentration and the occurrence of renal dysfunction remains unclear. This study aimed to examine the impact of the predicted free blood concentration on the development of renal dysfunction.

Methods: This retrospective study included patients who underwent TEIC and had at least one trough concentration measurement. The association between the frequency of renal dysfunction occurrence and the predicted free blood concentration was evaluated using the following equation: free TEIC concentration = total TEIC concentration/(1 + 1.78 × serum albumin level).

Results: Of the 170 patients included in this study, 18% (31/170) developed renal dysfunction. The predicted free trough concentration was significantly higher in the renal dysfunction onset group than in the nononset group. However, the total trough concentration was not significantly associated with the development of renal dysfunction. The odds ratio for developing renal dysfunction was 4.5 (95% confidence interval, 1.9-10.5; P < 0.001) when the predicted free trough concentration was > 4.0 µg/mL.

Conclusion: Elevated free trough concentrations of TEIC were associated with an increased risk of renal dysfunction. Controlling the increase in the predicted free blood concentration may effectively prevent the development of renal dysfunction.