Cefamandole in the therapy of experimental pneumococcal meningitis

The cerebrospinal fluid penetration and bactericidal activity of cefamandole nafate, cephaloridine, cefazolin, cephalothin and penicillin G were compared in an animal model of pneumococcal meningitis. In the presence of serum levels considered therapeutic in man cephaloridine CSF concentrations were 15 % of those found in serum; cefamandole, cefazolin, and penicillin G were approximately 3%; and cephalothin was less than 1 %. In vitro all antibiotics killed at approximately the same rate. In vivo all cephalosporins except cephalothin attained CSF concentrations considerably greater than the minimum bactericidal concentration when administered at 30 mg/kg/h and produced a bactericidal effect equal to penicillin G. Cephalothin CSF concentrations were equal to or slightly greater than the MBC, but failed to kill the organisms in vivo.