Background: The combination of cefotaxime and fosfomycin (CTX-FOS) has been proposed in France for the empirical treatment of postoperative nosocomial meningitis since the late 1980s. The purpose of this work was to evaluate this strategy today, as well as other possible treatments.
Methods: Each patient undergoing a neurosurgical procedure was prospectively included in a database designed for the surveillance of surgical site infection (SSI). For each meningitis detected, we analysed the in vitro susceptibility of the causative micro-organisms to cefotaxime alone (CTX), cefotaxime-fosfomycin (CTX-FOS), vancomycin (VAN) and cefotaxime-vancomycin (CTX-VAN) combinations. The patient population was divided into two groups according to the presence or absence of CSF shunting material.
Findings: 116 patients had had a postoperative meningitis/ventriculitis during the last 36 months, among 6447 patients undergoing neurosurgery in our department (1.8%). Ten patients had aseptic meningitis (8.6%). Overall sensitivity to CTX was 69.8%, as compared to 77.3% with CTX-FOS combination (NS). This result was due to a large proportion of fosfomycin resistant cocci in our population. The CTX-VAN combination increased the overall in vitro susceptibility up to 91.5%, but the benefit of this combination was only significant in CSF shunting material patients. In these latter patients, VAN was as effective as CTX-FOS combination.
Interpretation: CTX-FOS combination is no longer the best choice for empirical treatment of post neurosurgical meningitis. CTX alone can be safely used in patients without a CSF shunt; in those with either a ventriculostomy or a CSF shunt associated ventriculitis, a CTX-VAN combination could improve treatment efficacy, provided that high doses of vancomycin are used to ensure correct CSF diffusion.