Determination by LC–MS/MS of Colistins A and B in Plasma and Ultrafiltrate From Critically Ill Patients Undergoing Continuous Venovenous Hemodiafiltration
- 1 April 2014
- journal article
- research article
- Published by Ovid Technologies (Wolters Kluwer Health) in Therapeutic Drug Monitoring
- Vol. 36 (2), 182-191
- https://doi.org/10.1097/ftd.0b013e3182a8997c
Abstract
Colistin is a 50-year-old antibiotic, the use of which was ceased in the 70s and recently resumed as a "salvage therapy" against multidrug-resistant gram-negative bacteria, such as Pseudomonas aeruginosa and Acinetobacter baumannii. The narrow therapeutic range of colistin makes the choice of its correct dosage crucial, and monitoring of blood concentration is occasionally necessary for critically ill patients, including intensive care patients subjected to continuous renal replacement therapy. Two LC-MS/MS methods were developed and fully validated for the quantitative determination of colistins A and B in plasma and dialysis ultrafiltrate (UF) samples, ultimately arising from 4 patients undergoing continuous venovenous hemodiafiltration (CVVHDF). The developed methods proved to be both specific and selective. They showed good fit and linearity over the entire range of interest. Trueness and accuracy proved satisfactory. Both methods have excellent intraassay precision (percent coefficient of variations were lower than 10%) and limit of detection values in the range 20-100 ng/mL, about 1-2 orders of magnitude below the concentrations commonly detected in real samples. The mean sieving coefficient (SC) values, measured after 10 minutes of CVVHDF, were 0.42 for colistin A and 0.48 for colistin B. SC values proved to be quite stable for 24 hours, but then declined to 0.24 for colistin A and 0.32 for colistin B, respectively, after 48 hours. At the median blood flow and effluent flow rate of 120 and 28 mL/min, clearance values for colistin B were higher than 15 mL/min. During the entire duration of CVVHDF sessions, the SC and clearance values for colistin A were significantly lower than colistin B. Two simple methods for the simultaneous determination of colistins A and B have been developed and validated. Their application in the clinical setting demonstrates that CVVHDF treatment lasting 48 hours produces a relatively constant and efficient removal of the drug.Keywords
This publication has 27 references indexed in Scilit:
- Assay of Colistin and Colistin Methanesulfonate in Plasma and Urine by Liquid Chromatography-Tandem Mass SpectrometryAntimicrobial Agents and Chemotherapy, 2010
- Colistin in the 21st centuryCurrent Opinion in Infectious Diseases, 2009
- Population Pharmacokinetic Analysis of Colistin Methanesulfonate and Colistin after Intravenous Administration in Critically Ill Patients with Infections Caused by Gram-Negative BacteriaAntimicrobial Agents and Chemotherapy, 2009
- Nephrotoxicity Associated with Intravenous Colistin (Colistimethate Sodium) Treatment at a Tertiary Care Medical CenterClinical Infectious Diseases, 2009
- Toxicity of polymyxins: a systematic review of the evidence from old and recent studiesCritical Care, 2006
- Antibiotic Dosing in Critically Ill Adult Patients Receiving Continuous Renal Replacement TherapyClinical Infectious Diseases, 2005
- Evaluation of colistin as an agent against multi-resistant Gram-negative bacteriaInternational Journal of Antimicrobial Agents, 2005
- The Pharmacokinetics of Colistin in Patients with Cystic FibrosisThe Journal of Clinical Pharmacology, 2001
- Polymyxin B Sulfate and Colistin: Old Antibiotics for Emerging Multiresistant Gram-Negative BacteriaAnnals of Pharmacotherapy, 1999
- Adverse Effects of Sodium ColistimethateAnnals of Internal Medicine, 1970