Multidrug-Resistant Acinetobacter Baumannii Meningitis: A Case Report

Healthcare-associated meningitis is an increasing challenge, especially in patients undergoing neurosurgical procedures or using intracranial devices. Among the causative agents, Acinetobacter baumannii stands out for its ability to form biofilms, survive on dry surfaces for prolonged periods, and present resistance to multiple antibiotic classes, including carbapenems. This resistance significantly limits therapeutic options, increasing morbidity and mortality. In cases of multidrug-resistant A. baumannii infections, intrathecal or intraventricular administration of polymyxins, particularly colistin, has emerged as an effective alternative. This route allows high drug concentrations in the cerebrospinal fluid, overcoming the blood–brain barrier and enhancing antimicrobial activity in the central nervous system. Although evidence remains limited and mainly based on observational studies, available data suggest that this approach may improve microbiological clearance of the CSF and reduce mortality in infections caused by highly resistant Gram-negative bacilli. Clinical data obtained from medical records and examinations during hospitalization were used. P.F.A., male, 72 years old, presented with fever, chills, and malaise for 30 days, progressing to back pain. Magnetic resonance imaging revealed thoracic spondylodiscitis. He underwent laminectomy followed by thoracic arthrodesis with external drainage. After 32 days of hospitalization, he developed meningitis caused by multidrug-resistant A. baumannii, with resistance to amikacin, tigecycline, and polymyxin. Treatment included intrathecal polymyxin B for 21 days, resulting in negative CSF cultures, clinical improvement, and hospital discharge. Multidrug-resistant A. baumannii meningitis is a condition that is difficult to manage, particularly in complex neurological settings. Limited antibiotic penetration into the central nervous system necessitates innovative therapeutic alternatives. Intrathecal administration of polymyxins emerges as a promising strategy, with the potential to increase treatment efficacy and reduce adverse outcomes. Despite limitations in available studies, the observed clinical results indicate significant benefits when this approach is applied judiciously and with appropriate monitoring, contributing to the management of nosocomial infections caused by multidrug-resistant pathogens.