{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,23]],"date-time":"2025-12-23T10:59:06Z","timestamp":1766487546997,"version":"3.48.0"},"reference-count":11,"publisher":"BMJ","issue":"12","content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["BMJ Case Rep"],"accepted":{"date-parts":[[2025,12,8]]},"published-print":{"date-parts":[[2025,12]]},"abstract":"<jats:p>Anti-\u03b1-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor limbic encephalitis is a rare neurological disorder often associated with malignancies. We present the case of a patient in her forties who initially presented with symptoms misattributed to migraine, later progressing to fever, confusion, declining consciousness and focal seizures. MRI findings were consistent with encephalitis, and cerebrospinal fluid (CSF) analysis revealed lymphocytic pleocytosis with negative infectious workup. Despite initial empiric treatment for infectious encephalitis, her condition deteriorated. CT of the chest, abdomen and pelvis showed suspicious nodules in the left breast; biopsy confirmed the presence of metastatic invasive ductal carcinoma. She made a marked improvement following plasma exchange. Subsequently, the CSF autoimmune encephalitis panel returned positive for AMPA receptor antibodies, confirming the diagnosis of paraneoplastic encephalitis. This case underscores the need for early consideration of autoimmune and paraneoplastic causes in atypical or refractory encephalitis presentations, even prior to the availability of confirmatory antibody testing.<\/jats:p>","DOI":"10.1136\/bcr-2025-268324","type":"journal-article","created":{"date-parts":[[2025,12,23]],"date-time":"2025-12-23T10:55:20Z","timestamp":1766487320000},"page":"e268324","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":0,"title":["Anti-AMPA receptor limbic encephalitis as the initial manifestation of metastatic breast cancer"],"prefix":"10.1136","volume":"18","author":[{"given":"Naveed Ullah","family":"Khan","sequence":"first","affiliation":[{"name":"Department of Neurology, Lancashire Teaching Hospitals NHS Foundation Trust, Preston, Lancashire, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0004-7012-8808","authenticated-orcid":false,"given":"Syed Mustafa","family":"Ali","sequence":"additional","affiliation":[{"name":"Department of Neurology, Lancashire Teaching Hospitals NHS Foundation Trust, Preston, Lancashire, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Deepa Gharpuray","family":"Pandit","sequence":"additional","affiliation":[{"name":"Department of Cellular Pathology, Lancashire Teaching Hospitals NHS Foundation Trust, Preston, Lancashire, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Suresh Kumar","family":"Chhetri","sequence":"additional","affiliation":[{"name":"Department of Neurology, Lancashire Teaching Hospitals NHS Foundation Trust, Preston, England, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"239","published-online":{"date-parts":[[2025,12,23]]},"reference":[{"key":"2025122302551007000_18.12.e268324.1","doi-asserted-by":"publisher","DOI":"10.1136\/practneurol-2020-002567"},{"key":"2025122302551007000_18.12.e268324.2","doi-asserted-by":"publisher","DOI":"10.31887\/DCNS.2013.15.1\/jhenley"},{"key":"2025122302551007000_18.12.e268324.3","doi-asserted-by":"crossref","first-page":"405","DOI":"10.1002\/acn3.52260","article-title":"Psychiatric manifestations of encephalitis","volume":"12","author":"Bean","year":"2025","journal-title":"Ann Clin Transl Neurol"},{"key":"2025122302551007000_18.12.e268324.4","doi-asserted-by":"crossref","first-page":"2403","DOI":"10.1212\/WNL.0000000000001682","article-title":"Encephalitis and AMPA receptor antibodies: Novel findings in a case series of 22 patients","volume":"84","author":"H\u00f6ftberger","year":"2015","journal-title":"Neurology (ECronicon)"},{"key":"2025122302551007000_18.12.e268324.5","doi-asserted-by":"publisher","DOI":"10.1007\/s13244-016-0481-x"},{"key":"2025122302551007000_18.12.e268324.6","doi-asserted-by":"crossref","first-page":"25","DOI":"10.3389\/fpsyt.2017.00025","article-title":"Red Flags: Clinical Signs for Identifying Autoimmune Encephalitis in Psychiatric Patients","volume":"8","author":"Herken","year":"2017","journal-title":"Front Psychiatry"},{"key":"2025122302551007000_18.12.e268324.7","doi-asserted-by":"publisher","DOI":"10.1093\/neuonc\/nou030"},{"key":"2025122302551007000_18.12.e268324.8","doi-asserted-by":"crossref","first-page":"459","DOI":"10.3949\/ccjm.88a.20122","article-title":"Antibody-mediated autoimmune encephalitis: A practical approach","volume":"88","author":"Abbatemarco","year":"2021","journal-title":"CCJM"},{"key":"2025122302551007000_18.12.e268324.9","doi-asserted-by":"crossref","first-page":"100552","DOI":"10.1016\/j.ejro.2024.100552","article-title":"Autoimmune encephalitis: Early and late findings on serial MR imaging and correlation to treatment timepoints","volume":"12","author":"Abunada","year":"2024","journal-title":"Eur J Radiol Open"},{"key":"2025122302551007000_18.12.e268324.10","doi-asserted-by":"crossref","first-page":"653","DOI":"10.1007\/s00234-024-03318-x","article-title":"Autoimmune encephalitis: what the radiologist needs to know","volume":"66","author":"Sanvito","year":"2024","journal-title":"Neuroradiology"},{"key":"2025122302551007000_18.12.e268324.11","unstructured":"Gole S , Anand A . Autoimmune encephalitis. In: StatPearls. StatPearls Publishing, 2025. Available: http:\/\/www.ncbi.nlm.nih.gov\/books\/NBK578203\/ [accessed 17 May 2025]."}],"container-title":["BMJ Case Reports"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/syndication.highwire.org\/content\/doi\/10.1136\/bcr-2025-268324","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,12,23]],"date-time":"2025-12-23T10:55:21Z","timestamp":1766487321000},"score":1,"resource":{"primary":{"URL":"https:\/\/casereports.bmj.com\/lookup\/doi\/10.1136\/bcr-2025-268324"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,12]]},"references-count":11,"journal-issue":{"issue":"12","published-online":{"date-parts":[[2025,12,23]]},"published-print":{"date-parts":[[2025,12]]}},"alternative-id":["10.1136\/bcr-2025-268324"],"URL":"https:\/\/doi.org\/10.1136\/bcr-2025-268324","relation":{},"ISSN":["1757-790X"],"issn-type":[{"value":"1757-790X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,12]]}}}