Vancomycin removal during a plasma exchange transfusion.

Objective: To report a case of clinically significant removal of vancomycin during a plasma exchange transfusion in a patient with sickle-cell anemia.

Case Summary: A 46-year-old African American woman with sickle-cell disease was admitted on three separate occasions and treated with vancomycin. Vancomycin serum drug concentrations were obtained on all three admissions. During one of the admissions, a plasma exchange transfusion was performed the same day vancomycin concentrations were obtained. The vancomycin serum drug concentrations were considerably lower than predicted, resulting in potentially subtherapeutic vancomycin concentrations. Bayesian pharmacokinetic forecasting was used in interpreting the vancomycin concentrations.

Discussion: Searches from MEDLINE (1966-September 2000) and Drugs and Pharmacology (1990-September 2000) were performed to obtain pertinent published literature.

Conclusions: Plasma exchange transfusions may result in clinically significant removal of vancomycin from the plasma. The potential exists of underdosing vancomycin in patients who are receiving frequent plasma exchange transfusions. Further research may be warranted to determine whether these patients may be candidates for more frequent and vigilant monitoring of vancomycin concentrations.