Difficulties in differential diagnosis of glial tumors and limbic encephalitis: literature data, clinical observations

   Temporal and parahippocampal glial tumors at early morphological stages of their development may mimic the clinical and neuroimaging picture of limbic encephalitis. Delayed diagnosis of glioblastoma can have a negative impact on the prognosis of the disease, which is why there is a need to find approaches for its earlier detection.

   The aim of this paper is to analyze possible difficulties and errors in the differential diagnosis of autoimmune encephalitis (AE) and glioblastoma based on literature data and our own clinical observations.

   Features such as onset of the disease at a young age, subacute development of symptoms, response to immunosuppressive therapy and the MRI imaging of bilateral T2 hyperintense changes in the limbic areas are typical for AE, but do not exclude the diagnosis of a primary tumor of the central nervous system. Therefore, caution should be exercised regarding the likelihood of a primary brain tumor when patients of any age group present with symptoms characteristic of AE, especially if no specific for AE antibodies are detected. To shorten the time to diagnosis, a multidisciplinary approach, critical analysis of clinical data, a shortening of the examination interval and an increase in the frequency of imaging follow-up examinations are required.

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