{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,7]],"date-time":"2026-08-07T15:25:14Z","timestamp":1786116314093,"version":"build-2736575974"},"reference-count":35,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2026,8,6]],"date-time":"2026-08-06T00:00:00Z","timestamp":1785974400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Reports"],"abstract":"<jats:p>Background and Clinical Significance: Encephalitis is a rare neurological complication associated with Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection. In rare cases, focal neuroinflammation can manifest as a mass-like parenchymal lesion, creating profound diagnostic and treatment dilemmas by mimicking primary central nervous system neoplasms. Case Presentation: A 34-year-old female presented with cephalalgia, nausea, confusion, facial palsy, and a new onset of focal impaired awareness seizures (FIAS). Brain magnetic resonance imaging (MRI) revealed a prominent hyperintense lesion within the left temporal lobe with associated vasogenic edema and focal leptomeningeal enhancement highly suspicious of a low-grade glial neoplasm. Although nasopharyngeal RT-PCT was negative, the presence of serum anti-SARS-CoV-2 IgM and IgG suggested recent subclinical SARS-CoV-2 infection. To resolve diagnostic ambiguity and avoid empiric oncological overtreatment, a stereotactic brain biopsy was performed. Histopathology revealed acute neuroinflammation characterized by reactive gliosis, microglial hyperplasia, and perivascular lymphatic cuffing, with no evidence of neoplastic presence. Quantitative tissue RT-PCR confirmed the presence of SARS-CoV-2 (Ct33). Follow-up imaging demonstrated complete resolution of the abnormalities following conservative treatment with corticosteroids and antiepileptics, though mild clinical symptoms persisted for 12 months thereafter. Conclusions: Encephalitis presents a rare yet critical manifestation of SARS-CoV-2. Establishing definitive etiology remains challenging. Stereotactic biopsy is a valuable tool to guide appropriate treatment in cases of ambiguous imaging and clinical findings. Radiographic resolution may precede complete clinical recovery.<\/jats:p>","DOI":"10.3390\/reports9030258","type":"journal-article","created":{"date-parts":[[2026,8,6]],"date-time":"2026-08-06T08:08:02Z","timestamp":1786003682000},"page":"258","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Treatment and Diagnostic Challenges in a Patient with Atypical SARS-CoV-2-Associated Encephalitis Mimicking a Neoplasm: A Case Report"],"prefix":"10.3390","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6580-5382","authenticated-orcid":false,"given":"Marios","family":"Theologou","sequence":"first","affiliation":[{"name":"Department of Neurosurgery, General Hospital of Thessaloniki Georgios Papanikolaou, 57013 Thessaloniki, Greece"},{"name":"First Department of Neurosurgery, IASO General Clinic, 15123 Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Panagiotis","family":"Kyriakongonas","sequence":"additional","affiliation":[{"name":"First Department of Neurosurgery, IASO General Clinic, 15123 Athens, Greece"},{"name":"Department of Neurosurgery, 401 General Military Hospital of Athens, 11525 Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6703-8095","authenticated-orcid":false,"given":"Nikolaos","family":"Syrmos","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, General Hospital of Thessaloniki Georgios Papanikolaou, 57013 Thessaloniki, Greece"},{"name":"School of Medicine, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Theologos","family":"Theologou","sequence":"additional","affiliation":[{"name":"First Department of Neurosurgery, IASO General Clinic, 15123 Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"783","DOI":"10.1017\/S0950268810000725","article-title":"Causality in Acute Encephalitis: Defining Aetiologies","volume":"138","author":"Granerod","year":"2010","journal-title":"Epidemiol. 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