Excessively increased CSF glutamate levels in GABA _B -receptor antibody associated encephalitis: A case report

Limbic encephalitis (LE) is a rare and rather variable disease associated in part with different antibodies. The most frequent antibodies found are directed against NMDA-receptors or proteins of the voltage-gated potassium channels (LGI1, CASPR2). Additionally, in those patients suffering from LE with early and predominant seizures GABAB-receptor (GABAB-R) antibodies could be identified in serum and cerebrospinal fluid (CSF) [1]. Since blockade of GABAB-R leads to disinhibition [2], the question was raised whether the CSF profile of excitatory and inhibitory neurotransmitters is reflecting pathophysiological mechanisms of the disease.