Limbic encephalitis associated with anti-voltage-gated potassium channel complex antibodies as a cause of adult-onset mesial temporal lobe epilepsy.

Abstract

Recently, some reports have indicated that limbic encephalitis associated with anti-voltage-gated potassium channel complex antibodies (VGKC-Ab) is a cause of adult-onset mesial temporal lobe epilepsy (MTLE). We report a 53-year-old woman who had her first epileptic seizure at the age of 50 years old. Examination by 3-Tesla brain MRI revealed left hippocampal high signal intensity and swelling on fluid-attenuated inversion recovery (FLAIR) and T2-weighted imaging at 2 months after her first seizure. The patient received intravenous methylprednisolone and carbamazepine 300 mg/day. One month later, MRI revealed improvement of her left hippocampal abnormalities. Thereafter, she had no seizures, however, three years after her first seizure, EEG revealed a seizure pattern in the left temporal region. Brain MRI revealed left hippocampal high signal intensity and brain fluorodeoxyglucose positron emission tomography revealed hypermetabolism. Her serum VGKC-Ab levels were 118 pM(normal < 100 pM). Intravenous methylprednisolone therapy was reinitiated. Two months later, her hippocampal abnormalities had improved and 3 months later her VGKC-Ab levels decreased to 4.4 pM. Remission of the epileptic seizures was also observed. This MTLE in the middle age was considered as limbic encephalitis associated with anti- VGKC-Ab. In cases of unexplained adult-onset MTLE, limbic encephalitis associated with anti-VGKC-Ab, which responds well to immunotherapy, should be considered in the differential diagnosis.

• Authors: Tomoko Toyota, Naoki Akamatsu, Sadatoshi Tsuji, Shigeru Nishizawa
• Journal: Journal of UOEH (J UOEH) Vol. 36 Issue 2 Pg. 129-33 (Jun 01 2014) ISSN: 0387-821X [Print] Japan
• PMID: 24930877 (Publication Type: Case Reports, Journal Article)

Chemical References

• Autoantibodies
• Potassium Channels, Voltage-Gated

Topics

• Autoantibodies (immunology)
• Epilepsy, Temporal Lobe (etiology)
• Female
• Humans
• Limbic Encephalitis (complications, immunology)
• Middle Aged
• Potassium Channels, Voltage-Gated (immunology)