Inappropriate Antimicrobial Regimen Leading to Recurrent Listeria monocytogenes Meningitis: A PK/PD-Based Case Analysis and a Literature Review.

OBJECTIVE: To elucidate the pharmacokinetic/pharmacodynamic (PK/PD) characteristics of antimicrobial agents used in the treatment of Listeria monocytogenes (L. monocytogenes) meningitis and to provide evidence-based guidance for individualized dosing regimens in clinical practice. METHODS: A combined approach involving retrospective case analysis and a literature review was employed. The PK/PD characteristics of various antimicrobial agents applicable to the treatment of L. monocytogenes meningitis were comprehensively evaluated, and the rationality of different dosing regimens was assessed. RESULTS: Case analysis revealed that inappropriate antimicrobial selection and insufficient dosing contributed to early disease relapse during treatment. Furthermore, a review of 43 published case reports has demonstrated that ampicillin in combination with gentamicin remains the first-line therapy for L. monocytogenes meningitis. However, when penicillin-based agents are contraindicated, alternative antimicrobial agents should be selected according to cerebrospinal fluid (CSF) penetration and PK/PD characteristics, with optimized and standardized dosing regimens established accordingly. CONCLUSION: Selection of antimicrobial therapy for L. monocytogenes meningitis should be guided by pharmacokinetic principles. Individualized precision therapy based on lesion-site PK/PD characteristics is essential to improve treatment success and patient prognosis.