Hippocampal damage after prolonged febrile seizure: One case in a consecutive prospective series

• Published in: Epilepsia (Copenhagen) Vol. 52; no. 4; pp. 837 - 840
• Main Authors: Tanabe, Takuya, Hara, Keita, Shimakawa, Shuichi, Fukui, Miho, Tamai, Hiroshi
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.04.2011; Wiley-Blackwell; Wiley Subscription Services, Inc
• Subjects: Amnesia; Biological and medical sciences; Brain Damage, Chronic - diagnosis; Brain Damage, Chronic - etiology; Brain Damage, Chronic - pathology; Cell death; Cell Death - physiology; Child, Preschool; Convulsions & seizures; Epilepsy; Eye; Febrile seizure; Female; Headache. Facial pains. Syncopes. Epilepsia. Intracranial hypertension. Brain oedema. Cerebral palsy; Hemispheric laterality; Hippocampal atrophy; Hippocampus; Hippocampus - pathology; Hospitals; Humans; Infant; Inversion; Magnetic resonance image; Magnetic resonance imaging; Male; Medical sciences; Nerve Degeneration - diagnosis; Nerve Degeneration - etiology; Nerve Degeneration - pathology; Nervous system (semeiology, syndromes); Neurology; Neuropharmacology; Neuroprotective agent; Pharmacology. Drug treatments; Prolonged seizure; Rhythms; Seizures; Seizures, Febrile - complications; Seizures, Febrile - diagnosis; Seizures, Febrile - pathology; Febrile seizure; Nervous system diseases; Prolonged seizure; Epilepsy; Central nervous system; Febrile convulsion; Encephalon; Cerebral disorder; Hippocampal atrophy; Prospective; Central nervous system disease; Neurological disorder; In series; Hippocampus; Magnetic resonance image
• ISSN: 0013-9580; 1528-1167
• DOI: 10.1111/j.1528-1167.2010.02958.x

Summary The factors that contribute to hippocampal damage as a sequela, and its frequency, in patients experiencing febrile status epilepticus, remain unknown. Of the 472 patients with febrile seizures admitted to our hospital between February 2004 and August 2008, 77 had prolonged seizures. Among them, 59 underwent magnetic resonance imaging (MRI). A 21‐month‐old girl showed hippocampal changes after her first episode of febrile status epilepticus. The seizure lasted about 35 min, with eye deviation to the right and ictal rhythmic discharges in the left hemisphere. MRI at 72 h after the seizure revealed high‐signal intensities in T2 and fluid‐attenuated inversion recovery (FLAIR) images of the left hippocampus. Left hippocampal volume diminished over the next several months suggesting the occurrence of neuronal cell death. In no other cases, not even those with longer seizure durations, did significant hippocampal changes develop. The frequency of hippocampal damage was 1.7% in this case series. The involvement of factors other than seizure duration merits further study.