{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,4]],"date-time":"2026-06-04T12:23:00Z","timestamp":1780575780769,"version":"3.54.1"},"reference-count":21,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2024,12,14]],"date-time":"2024-12-14T00:00:00Z","timestamp":1734134400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"German Society for Geriatrics"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antibiotics"],"abstract":"<jats:p>Background: In hospital- and community-acquired central nervous system infections, resistant Gram-positive bacteria are an increasing therapeutic challenge. The present approach does not attempt to identify rapidly bactericidal therapies for susceptible pathogens but aims to improve methods to find antibiotic regimens for multi-resistant pathogens that are effective in vivo in spite of reduced in vitro susceptibility in culture media. Methods: Antibiotic susceptibility was tested in cerebrospinal fluid (CSF) and Mueller\u2013Hinton broth (Enterococcus faecalis, methicillin-resistant Staphylococcus aureus, Staphylococcus epidermidis) or brain\u2013heart infusion (Streptococcus pneumoniae). Results: Minimal inhibitory concentrations (MICs) and minimal bactericidal concentrations (MBCs) were either lower in CSF than in broth or equal in CSF and broth. The difference between MICs in CSF and broth was prominent with gentamicin, levofloxacin, linezolid (staphylococci), and vancomycin (staphylococci and pneumococcus), whereas it was absent with ampicillin (E. faecalis), penicillin G (S. pneumoniae), linezolid (enterococcus and pneumococcus), and vancomycin (enterococcus). In no case was the MIC or MBC higher in CSF than in broth. Conclusions: Several antibiotics possess an antibacterial effect in CSF at lower concentrations than the MICs determined in broth, i.e., MICs in broth underestimate in situ susceptibility in CSF.<\/jats:p>","DOI":"10.3390\/antibiotics13121215","type":"journal-article","created":{"date-parts":[[2024,12,16]],"date-time":"2024-12-16T04:14:52Z","timestamp":1734322492000},"page":"1215","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Increased Antibiotic Susceptibility of Gram-Positive Bacteria in Cerebrospinal Fluid Compared to Broth"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0009-0009-5738-3763","authenticated-orcid":false,"given":"Jennifer S.","family":"Wirth","sequence":"first","affiliation":[{"name":"Department of Geriatrics, Evangelisches Krankenhaus G\u00f6ttingen-Weende, 37075 G\u00f6ttingen, Germany"},{"name":"Department of Neuropathology, University Medical Center G\u00f6ttingen, 37073 G\u00f6ttingen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Marija","family":"Djukic","sequence":"additional","affiliation":[{"name":"Department of Geriatrics, Evangelisches Krankenhaus G\u00f6ttingen-Weende, 37075 G\u00f6ttingen, Germany"},{"name":"Department of Neuropathology, University Medical Center G\u00f6ttingen, 37073 G\u00f6ttingen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Katrin","family":"Biesner","sequence":"additional","affiliation":[{"name":"Department of Geriatrics, Evangelisches Krankenhaus G\u00f6ttingen-Weende, 37075 G\u00f6ttingen, Germany"},{"name":"Department of Neuropathology, University Medical Center G\u00f6ttingen, 37073 G\u00f6ttingen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Utz","family":"Reichard","sequence":"additional","affiliation":[{"name":"MVZ Wagnerstibbe, Amedes Group, 37081 G\u00f6ttingen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8316-995X","authenticated-orcid":false,"given":"Roland","family":"Nau","sequence":"additional","affiliation":[{"name":"Department of Geriatrics, Evangelisches Krankenhaus G\u00f6ttingen-Weende, 37075 G\u00f6ttingen, Germany"},{"name":"Department of Neuropathology, University Medical Center G\u00f6ttingen, 37073 G\u00f6ttingen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jana","family":"Seele","sequence":"additional","affiliation":[{"name":"Department of Geriatrics, Evangelisches Krankenhaus G\u00f6ttingen-Weende, 37075 G\u00f6ttingen, Germany"},{"name":"Department of Neuropathology, University Medical Center G\u00f6ttingen, 37073 G\u00f6ttingen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,12,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"691","DOI":"10.2165\/00003088-200241100-00001","article-title":"Considerations in the use of cerebrospinal fluid pharmacokinetics to predict brain target concentrations in the clinical setting: Implications of the barriers between blood and brain","volume":"41","author":"Danhof","year":"2002","journal-title":"Clin. 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