Enlarging the clinical spectrum of chorea-acanthocytosis

Abstract Chorea-acanthocytosis (ChAc) is a rare neurodegenerative disorder characterized by basal ganglia degeneration, leading to hyperkinetic movements, cognitive impairment, and psychiatric symptoms. This case study presents a unique manifestation of ChAc, starting with bipolar II disorder as the initial symptom, an observation not previously documented. The patient, a 68-year-old woman, developed recurrent depressive episodes, hypomanic symptoms, and psychotic manifestations before exhibiting progressive orofacial dyskinesias, dysphagia, and gait instability. Neurological examination revealed classic ChAc features, including tongue protrusion, motor impersistence, and caudate atrophy on MRI. Peripheral blood smear confirmed acanthocytosis, and Western blot analysis detected absent chorein protein, confirming the diagnosis. Treatment with tetrabenazine and clonazepam resulted in significant symptom improvement. This case expands the neuropsychiatric spectrum of ChAc, highlighting the potential for bipolar disorder as an early indicator and emphasizing the need for early recognition and tailored management.