Objective:

To describe a case of anti-leucine-rich glioma-inactivated 1 encephalitis (LGI1-E) presenting with trichotillomania and dermatillomania.

Background:

LGI1-E is a form of autoimmune encephalitis associated with antibodies targeting the LGI1 protein, a component of the voltage-gated potassium channel (VGKC) complex. It typically presents with faciobrachial dystonic seizures, subacute cognitive decline, and neurobehavioral disturbances. Early neuropsychiatric symptoms may be overlooked and attributed to a psychiatric disorder, leading to significant delay in diagnosis and treatment. We describe a case of LGI1-E presenting with trichotillomania and dermatillomania in the context of rapid cognitive changes.

Design/Methods:

Case Report

Results:

A 64-year-old left-handed man presented to the memory clinic with a 6-month history of short-term memory impairment, language difficulties, attentional deficits, and executive dysfunction. He also reported significant anxiety, new-onset compulsive behaviors including facial hair pulling and skin picking, as well as disrupted sleep. He also detailed some transient episodes of “weakness” with a prior inconclusive workup. He was independent primarily in IADLs. Neurological examination revealed intermittent, predominantly right-sided myoclonic-like movements and occasional transient speech disturbances, with rapid return to baseline.  Labs revealed mild hyponatremia (133). Multiple prolonged EEG recordings were negative for seizures. MRI of the brain demonstrated subtle asymmetry of the left mesial temporal lobe.  Serum anti-LGI1 antibodies were positive.

Early neuropsychiatric symptoms, particularly compulsive behaviors, are often underrecognized in LGI1-E. Recent evidence supports the concept of LGI1-E as a network disorder characterized by widespread disruption that extends beyond the limbic system, particularly affecting the frontoparietal and default mode networks. Cognitive and behavioral disturbances, such as compulsive behaviors, may serve as early clinical markers of the disease and should prompt consideration of autoimmune encephalitis to avoid delays in initiating immunotherapy.

Conclusions:

LGI1-E involves broad extra-limbic network dysfunction, and a high index of suspicion is warranted with new-onset compulsive behaviors accompanied by cognitive changes.