Objective:

To describe a case of Anti-LGI1 encephalitis presenting with a previously unassociated syndrome of taste impairment then loss of familiarity with routine flavors (jamais goûté) followed by epileptic amnesia and pilomotor seizures and review associated anatomy. 

Background:

Anti-LGI1 encephalitis is the most common cause of autoimmune limbic encephalitis. Previous cases report temporal lobe and faciobrachial dystonic seizures, SIADH, and progressive cognitive-behavioral changes with edema of the hippocampi and basal ganglia. Initial symptoms are poorly described, possibly due to delayed recognition of the condition. An often overlooked component of the limbic system is the gustatory system. Here we describe a case of early anti-LGI1 encephalitis with predominantly gustatory initial phenomenology with radiographic findings previously unreported in limbic encephalitis. 

Design/Methods:

Case report

Results:

A 64 y/o man developed acute alteration of taste and loss of familiarity with routine flavors (jamais goûté) then spells of piloerection with tachycardia and hypertension followed by absence of formation of new memories for 3 minutes. These spells evolved to include olfactory and musical hallucinations, déjà entendu, déjà vu, and jamais vu. After two weeks of spells he developed impaired topographic and autobiographical memory and increased emotional lability. MRI brain revealed focal edema of the left gustatory (VPM) thalamic nucleus with contrast enhancement, edema of the left primary gustatory cortex, and expected edema of the bilateral hippocampi with contrast enhancement. CSF analysis showed lymphocytic pleocytosis and hyperproteinorhachia. Treated with empiric acyclovir and pulse dose steroids with rapid and sustained resolution of spells. HSV1/2 PCR and other infectious testing returned negative. CSF antibody testing later returned positive for anti-LGI1 antibody.  

Conclusions:

The gustatory system is an important but often forgotten component of the limbic system with complex limbic reciprocal projections. Alteration in taste, not previously reported in limbic encephalitis, should be considered a possible early symptom to increase recognition/treatment and minimize deficit.