Selective involvement of temporal regions in a case of flavivirus encephalitis

Clinical manifestations of flavivirus infection may be various, from unapparent to severe meningoencephalitis. Our patient, 2 weeks after returning home from a holiday at Elba Island, developed biphasic fever, later associated with nausea and vomiting and followed by incoming seizures responsive to thiopental sodium only. Brain MRI showed bilateral hyperintensity (T2) in amygdale, hippocampus, left insular and temporal inferior cortex. Standard and microbiological CSF examination was normal, but microbiological serum analysis showed seroconversion for flavivirus. The patient came to our observation 6 months after disease onset and at that time he was affected by frequent seizures and severe cognitive impairment with behavioural disturbances; the patient also showed distal weakness with footstepping. EEG showed bitemporal epileptic foci. During the following months, seizures greatly decreased and cognitive status improved in response to a complex antiepileptic therapy. Flavivirus encephalitis should be taken into account in the differential diagnosis of encephalitis selectively involving temporal lobes.