Multidrug-resistant Gram-negative post-neurosurgical meningitis and the role of intraventricular colistin: a case series

: The aim of this study was to report the clinical experience of intraventricular colistin for the treatment of multi-resistant Gram-negative post-surgical meningitis in a tertiary hospital. Post-neurosurgical meningitis (PNM) is one of the life-threatening complications of neurosurgical procedures, and is frequently sustained by Acinetobacter baumannii and Klebsiella pneumoniae. Here we describe our experience of five cases of PNM caused by gram-negative multi-drug resistant (MDR) bacteria, treated with intraventricular (IVT) colistin, admitted to the Neurosurgery Unit of A.R.N.A.S. Civico of Palermo, Italy, from January 2016 to June 2020. In four patients the cerebrospinal fluid (CSF) culture was positive for A. baumannii, while in one patient it was positive for K. pneumoniae. IVT colistin therapy was administered for a median time of 18 days (range 7-29). The median time to CSF negativization was seven days (range 5-29). IVT colistin administration was associated with intravenous administration of meropenem and colistin in all patients. As regards clinical outcome, four patients were successfully treated and were subsequently discharged, while one patient died following respiratory complications and subsequent brain death. IVT colistin administration is an effective therapy for MDR post-neurosurgical meningitis and its administration is also prescribed by guidelines. However, IVT therapy for Gram-negative ventriculitis is mostly understudied. Our paper adds evidence for such treatment that can actually be considered life-saving.