Effective antimicrobial therapy depends on several factors including degree of activity against the pathogen, antibiotic resistance, and when relevant, optimal tissue penetration factors. Central nervous system (CNS) infections illustrate these points well. The pharmacokinetic (PK) parameters important in antibiotic blood cerebrospinal fluid barrier (BCB) penetration that is important in meningitis are different and do not predict blood brain barrier (BBB) penetration. Recently, we had a case of Mycoplasma pneumoniae encephalitis (MPE) which prompted a review of the antibiotic PK determinants of BBB penetration which differ markedly from those of BCB penetration important in encephalitis. Using MPE as an illustrative example, this article reviews host and drug factors of therapeutic importance in optimally treating MPE.
Keywords: Antibiotic lipid solubility; Antibiotic penetration across brain barrier (BPB); Blood brain barrier (BBB); CNS manifestations of Mycoplasma pneumoniae; Tissue penetration of hydrophilic and hydrophilic antibiotics.