Prolonged psychosis before onset of neurological symptoms; an atypical clinical manifestation of Huntington’s disease

Huntington's disease (HD) is a rare, autosomal dominant, progressive neurodegenerative disorder. HD manifests with a triad of progressive motor, cognitive, and psychiatric symptoms. Our patient, a 39-years-old married female with over a nine-year history of psychotic symptoms. The patient was diagnosed and treated for schizophrenia. Over the last 2-3 years, the patient had a progressive decline in her Activities of Daily Living, instrumental activities of daily living, and psychotic symptoms. She developed slurred speech, gait disturbances, frequent falls, involuntary movements of the trunk and distal extremities, bowel and bladder incontinence, and severe weight loss. Her genetic test for Huntington’s gene confirmed the diagnosis of HD. She was prescribed Olanzapine, fluoxetine, and clonazepam. Psychotic symptoms are rare in HD and usually appear well after the motor and cognitive symptoms. Our case highlights an unusual clinical presentation of HD, which can be diagnostically challenging and lead to diagnostic delays.