Gram-negative bacillary meningitis. New therapy and changing concepts.

Because the CSF is deficient in opsonic and phagocytic activity, optimal therapy for meningitis mandates the use of antibiotics that are bactericidal at achievable CSF concentrations. This therapeutic principles is satisfied for the common meningeal pathogens (Streptococcus pneumoniae, Haemophilus influenzae, Neisseria meningitidis) but is not readily achieved for the pathogens causing Gram-negative bacillary meningitis (GNBM), such as Klebsiella and Escherichia coli. The antibiotics used to treat GNBM, chloramphenicol and aminoglycosides, are not bactericidal against enteric pathogens at achievable CSF levels. Two new beta-lactam antibiotics, moxalactam disodium and cefotaxime sodium, are suitable agents for the treatment of GNBM. These antibiotics possess potent bactericidal activity against most enteric pathogens and achieve high levels in the CSF (15 to 35 micrograms/mL for moxalactam disodium and 2 to 10 micrograms/mL for cefotaxime sodium). Recent clinical studies document an 85% cure rate when these agents are used to treat GNBM.