Empiric treatment of multidrug-resistant Burkholderia cepacia lung exacerbation in a patient with cystic fibrosis:: Application of pharmacodynamic concepts to meropenem therapy

A 31-year-old man with cystic fibrosis was diagnosed with multidrug-resistant Burkholderia cepacia pneumonia. Meropenem 2000 mg every 8 hours was administered as a 3-hour infusion to maximize pharmacodynamic exposure; oral minocycline 100 mg twice/day was also given. Blood samples were collected to confirm meropenem concentrations. Concentrations above the mimimum inhibitory concentration (MIC) of 8 mug/ml were achieved for 52% of the dosing interval, which is greater than what is required for a bactericidal effect. The patient's condition improved, he was discharged, and completed a 3-week course of the antibiotic regimen. After 6 months, he had remained at his baseline level of health. This case demonstrates that pharmacodynamic principles can be used to design an antibiotic dosing regimen that can achieve optimal exposures when the MIC is above that considered susceptible to conventional dosing strategies.