Pitfalls in diagnosing limbic encephalitis - a case report.Acta Neurol Scand. 2008 Nov; 118(5):339-42.AN
The syndrome of limbic encephalitis (LE) is characterized by subacute onset of temporal lobe epilepsy, loss of short-term memory, cognitive confusion and psychiatric symptoms.
We report a patient with pharmacoresistant epilepsy who underwent presurgical video-electroencephalogram (EEG)-monitoring with normal psychiatric and neuropsychological findings.
Magnetic resonance imaging (MRI) revealed a hyperintense lesion within the right amygdala but no contrast enhancement. Analysis of cerebrospinal fluid (CSF) showed pleocytosis and positive oligoclonal bands, but all tests for neurotropic viruses or borrelia antibodies were negative. Presurgical evaluation identified a right mesiotemporal focus.
As a tumour was the most likely differential diagnosis, we performed selective amygdalohippocampectomy of the right hemisphere. Subsequent histopathological examination revealed the surprising diagnosis of LE. As a consequence, tumour screening was initiated and a testicular carcinoma with high anti-Ma2-antibody titres was detected. Following surgical and chemotherapeutical treatment, the patient was seizure-free and Ma2-antibodies decreased below detection limits. Conclusion - This case report highlights that LE has to be considered even in patients with atypical clinical presentation, i.e. without neuropsychological deficits, if CSF analysis reveals an inflammatory response. When LE is diagnosed, extensive tumour search is mandatory to detect and treat the paraneoplastic origin of LE. Therapeutic strategies of LE include surgical treatment as well as early immunosuppression.