RESUMEN
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.
Asunto(s)
Anemia de Células Falciformes/sangre , Anemia de Células Falciformes/terapia , Antibacterianos/farmacocinética , Intercambio Plasmático/efectos adversos , Vancomicina/farmacocinética , Antibacterianos/uso terapéutico , Infecciones Bacterianas/tratamiento farmacológico , Infecciones Bacterianas/microbiología , Teorema de Bayes , Femenino , Humanos , Persona de Mediana Edad , Plasmaféresis , Vancomicina/uso terapéuticoRESUMEN
We conducted a post hoc pharmacoeconomic analysis of a multicenter, open-label, randomized, parallel-group, 8-week efficacy-safety comparison of five HMG-CoA reductase inhibitors-atorvastatin, fluvastatin, lovastatin, pravastatin, and simvastatin. The 534 patients requiring cholesterol-lowering therapy took the drugs for 8 weeks with 15 different regimens. Low-density lipoprotein (LDL) was measured after 6 weeks of diet (baseline) and after 8 weeks of treatment with a study drug. At dosages of 10, 20, and 40 mg/day, atorvastatin was associated with significantly greater reductions in LDL than equivalent dosages of the other agents. Cost-effectiveness calculated as the annual acquisition cost/percentage LDL reduction was greatest with atorvastatin 10 mg ($17.96), fluvastatin 40 mg ($19.83), atorvastatin 20 mg ($22.85), and atorvastatin 40 mg ($24.96). All other dosages were above $25.00/year/percentage LDL reduction. Atorvastatin was the most cost-effective HMG-CoA reductase inhibitor. Fluvastatin 40 mg/day also had a favorable cost:effectiveness ratio but lowered LDL only by 23%.