TDM of Antibiotics – when and how?
Therapeutic monitoring of antibiotics is particularly important for drugs with a narrow therapeutic concentration spectrum, or for those with a high risk of toxic side effects. More accurate, and individualized, monitoring can also optimize the therapeutic efficiency, while reducing the risk of any resistance developing. Consequently, labs are looking into introducing TDM for these drugs. The aim: an optimal patient care in collaboration with the treating physician.
Prof. Holdenrieder at the German Heart Centre (Munich) reported on an interdisciplinary program of physicians, pharmacy, hygienics, microbiology and laboratory medicine, which combines specialist knowledge from experts across all fields for optimal drug assessment and therapeutic counselling. Recent experiences in implementing HPLC methods for the quantification of antibiotics meropenem, linozelide, piperacillin, ampicillin, cefipim and ceftazidim were also presented and discussed.
Dr Heike Schneider from the Klinikum rechts der Isar (Munich) reported on a successful proficiency pilot test that was carried out in January 2018. It covered ampicillin, cefepime, ceftazidime, linezolid, meropenem, piperacillin, sulbactam and tazobactam. The study aimed to support a better standardization of monitoring of these drugs. “There are plans to establish a regular quality assessment scheme in the near future”, Schneider added.
Dr Oliver Midasch emphasized that, so far, there has been no commercially available method for these antibiotics. But he showcased the new Chromsystems assay for HPLC; that, with a simple sample preparation, combined with the chromatographic setup, a fast and secure determination of these important substances can be achieved without the requirement of highly sophisticated lab equipment. Two internal standards are used for a precise quantification and stable calibration. “Control materials are also available to ensure accuracy of results”, Midasch added.