{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T01:46:15Z","timestamp":1760060775202,"version":"build-2065373602"},"reference-count":23,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2025,9,25]],"date-time":"2025-09-25T00:00:00Z","timestamp":1758758400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JoF"],"abstract":"<jats:p>A 47-year-old woman presented with a two-year history of progressive visual symptoms and headaches. Lumbar puncture revealed lymphocytic pleocytosis, elevated protein, low glucose, and a CSF CrAg titer of 1:256. She was treated empirically for cryptococcal meningitis with amphotericin B, flucytosine, and fluconazole for 15 months. Her symptoms persisted, and repeated CSF and serum CrAg, fungal cultures, and an extensive infectious workup were negative. CSF flow cytometry eventually demonstrated a monoclonal B-cell population suggestive of a lymphoproliferative process. Imaging, including MRI and PET scans, did not reveal systemic disease. A ventriculoperitoneal (VP) shunt was placed for symptom management. This case emphasizes the limitations of CrAg testing and the potential for false positives. It underscores the need for integrating clinical, laboratory, and imaging data when evaluating chronic meningitis.<\/jats:p>","DOI":"10.3390\/jof11100697","type":"journal-article","created":{"date-parts":[[2025,9,25]],"date-time":"2025-09-25T12:05:13Z","timestamp":1758801913000},"page":"697","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["The Diagnostic Challenge of a False-Positive Cryptococcal Antigen in Chronic Meningitis with Suspected Indolent CNS B-Cell Lymphoproliferative Neoplasm"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2410-6788","authenticated-orcid":false,"given":"MohammadReza Rahimi","family":"Shahmirzadi","sequence":"first","affiliation":[{"name":"Division of Infectious Diseases, Western University, London, ON N6A 4V2, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Melissa","family":"Fowler","sequence":"additional","affiliation":[{"name":"Division of Infectious Diseases, Western University, London, ON N6A 4V2, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1692-7217","authenticated-orcid":false,"given":"Lise","family":"Bondy","sequence":"additional","affiliation":[{"name":"Division of Infectious Diseases, Western University, London, ON N6A 4V2, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4961-237X","authenticated-orcid":false,"given":"Seth","family":"Climans","sequence":"additional","affiliation":[{"name":"Department of Clinical Neurological Sciences, Western University, London, ON N6A 5W9, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jonathan","family":"Lau","sequence":"additional","affiliation":[{"name":"Department of Clinical Neurological Sciences, Western University, London, ON N6A 5W9, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Eric","family":"To","sequence":"additional","affiliation":[{"name":"Division of Hematology and Oncology, Western University, London, ON N6A 5W9, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0001-2437-7676","authenticated-orcid":false,"given":"Yiannis","family":"Iordanous","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Western University, London, ON N6A 4V2, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1498-2220","authenticated-orcid":false,"given":"Marilyn","family":"Phung","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, Western University, London, ON N6A 5W9, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3978-1823","authenticated-orcid":false,"given":"Fatimah","family":"AlMutawa","sequence":"additional","affiliation":[{"name":"Department of Pathology and Laboratory Medicine, Western University, London, ON N6A 5W9, Canada"},{"name":"Department of Microbiology and Immunology, Western University, London, ON N6A 3K7, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jeff","family":"Fuller","sequence":"additional","affiliation":[{"name":"Department of Pathology and Laboratory Medicine, Western University, London, ON N6A 5W9, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Michael","family":"Silverman","sequence":"additional","affiliation":[{"name":"Division of Infectious Diseases, Western University, London, ON N6A 4V2, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,9,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1298","DOI":"10.1212\/CON.0000000000000664","article-title":"Chronic Meningitis","volume":"24","author":"Thakur","year":"2018","journal-title":"Continuum"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"930","DOI":"10.1056\/NEJMra2032996","article-title":"Chronic Meningitis","volume":"385","author":"Aksamit","year":"2021","journal-title":"N. 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