Overall, nine cases with CNS infection were recorded aged from 22 to 74, all males. LP was performed between the second and 17th day (average 8.3 days) and the CSF analysis showed 40 to 6,000 cells - mainly PMNs, protein 161 mg% to 287 mg% and glucose from 3 to 58 mg/dl. They were all colonized with Acinetobacter baumannii sensitive only to colistin. CSF cultures were negative for all patients besides one, who grew A. baumannii. Of those, seven (77%) were receiving i.v. colistin, eight (88%) carbapenems, and eight (88%) glycopeptides, all in combination with other antibiotics. Median i.t. administration time was 9.1 days. All patients responded to i.v. and i.t. antibiotics but there was one case in which fever relapsed and increased number of cells in subsequent LP was observed which was attributed to colistin, which was withdrawn. All these patients survived, and were discharged to the ward.