Removal of linezolid by conventional intermittent hemodialysis, sustained low-efficiency dialysis, or continuous venovenous hemofiltration in patients with acute renal failure.

OBJECTIVE

To study the removal of linezolid, a new oxazolidinone antibiotic, by renal replacement therapy in patients with acute renal failure.

DESIGN

Prospective, single-dose pharmacokinetic study.

SETTING

Renal intensive care unit of a tertiary university hospital.

PATIENTS

Fifteen critically ill patients with oliguric acute renal failure on renal replacement therapy (seven males, mean age 72.3 yrs, range 60-94; Acute Physiology and Chronic Health Evaluation II score 24.9, range 18-36; mechanical ventilation ten of 15).

INTERVENTIONS

All patients received 600 mg of intravenous linezolid before starting renal replacement therapy, which consisted of intermittent hemodialysis lasting 3-4 hrs in eight patients, sustained low-efficiency dialysis lasting 8 hrs in five patients, and continuous venovenous hemofiltration lasting 10.5-12 hrs in two patients.

MEASUREMENTS AND MAIN RESULTS

Linezolid concentrations were measured by liquid chromatography/mass spectrometry methods on serum and dialysate/ultrafiltrate samples. At the start of renal replacement therapy, serum levels averaged 11.91 mg/L (range 5.49-21.52) and dropped at the end to levels <4 mg/dL (90% minimum inhibitory concentration values for Staphylococcus aureus) in three of eight patients on hemodialysis, three of five patients on sustained low-efficiency dialysis, and two of two patients on continuous venovenous hemofiltration. Mean removal of the drug was 193.7 mg with hemodialysis (32.3% of the dose administered), 205 mg with sustained low-efficiency dialysis (33.9%), and 74.8 mg (12.4%) and 105 (17.5%) mg following a continuous venovenous hemofiltration session lasting 10.5 and 12 hrs, respectively.

CONCLUSIONS

In patients with acute renal failure, serum levels of linezolid can be reduced to the subtherapeutic range following renal replacement therapy.