LC-MS/MS for Therapeutic Drug Monitoring of anti-infective drugs

Therapeutic drug monitoring (TDM) is a tool used to integrate pharmacokinetic and pharmacodynamic knowledge to optimise and personalize drug therapy. TDM is of specific interest for anti-infectives: to assure adequate drug exposure and reduce adverse events, to increase patient compliance and to prevent antimicrobial resistance. For TDM, drug blood concentrations are determined to bring and keep the concentration within the targeted therapeutic range. Currently, LC-MS/MS is the primary analytical technique for fast and accurate quantification of anti-infective drug concentrations. In addition to blood, several alternative matrices (cerebrospinal fluid, inflammatory fluids, specific cells and tissue) and alternative sampling strategies (dried blood spot and saliva) are currently being explored and introduced to support TDM. Here, we review the current challenges in the bioanalysis of anti-infective drugs and give insight in the pre- and postanalytical issues surrounding TDM.