Therapeutic drug monitoring for colistin therapy in severe multi-resistant Acinetobacter intracerebral abscess: A single case study with high-dose colistin and review of literature.

OBJECTIVES: Intracranial infections due to multidrug- resistant (MDR) gram-negative pathogens are associated with increased morbidity and mortality. As therapeutic options are limited and systemic drug penetration into the infection focus is difficult, intraventricular therapy has been described.

METHODS: We report on a patient with intracranial abscess caused by MDR Acinetobacter baumannii.

RESULTS: He was treated with high doses of intravenous and intraventricular colistin resulting in microbiological clearance and clinical cure. Therapy was controlled by therapeutic drug monitoring (TDM) of serum and liquor colistin levels. About 100 cases with intraventricular or intrathecal colistin are reported in literature but data on TDM are sparse.

CONCLUSIONS: This is one of the first cases providing data on TDM for locally administered high dose colistin therapy for the treatment of intracranial abscess formations. Based on these findings, increasing the intraventricular application interval paralleled with intravenous colistin could possibly be sufficient to achieve appropriate therapeutic drug levels. Further studies are needed to support alternative dosing strategies in similar cases.