Criss-cross gait: A clue to glucose transporter type 1 deficiency syndrome.

Nearly 90% of patients with glucose transporter type 1 deficiency syndrome (Glut1 DS; figure) have paroxysmal or constant gait abnormalities, including ataxic, spastic, ataxic-spastic, and dystonic gait.1,2 We report 3 cases of genetically proven Glut1 DS (table) demonstrating a distinctive paroxysmal gait disorder triggered by exertion or fasting, herein named “criss-cross gait” (video 1). It is characterized by lower-body choreo-dyskinesia causing the legs to intersect repeatedly, producing irregular, random steps combined with some loss of balance. Compensatory upper-body movements help maintain balance. In the appropriate clinical context, criss-cross gait should prompt evaluation for the treatable Glut1 DS and not be misinterpreted as functional.