Acute psychosis in a verified Huntington disease gene carrier with subtle motor signs: psychiatric criteria should be considered for the diagnosis.

Huntington disease (HD) is an inherited, progressive, autosomal dominant disorder. Some patients develop severe chorea or cognitive symptoms. The genetic defect causes progressive atrophy of the striatum, the cortex and extrastriatal structures (Sheperd GM. Corticostriatal connectivity and its role in disease. Nat Rev Neurosci 2013;14:278-91). The precise timing of clinical diagnosis of HD is poorly characterized and is mainly based on motor symptoms (Huntington, Study and Group. Unified Huntington's Disease Rating Scale: reliability and consistency. Huntington Study Group. Mov Discord 1996:136-42). Patients suffering from HD frequently show cognitive or affective symptoms even before manifesting motor signs. Psychiatric symptoms like depression, apathy, aggression, and disinhibition are common, and suicide rates are over four times higher than in the general population (Di Maio L, Squitieri F, Napolitano G, Campanella G, Trofatter JA, Conneally PM. Suicide risk in Huntington's disease. J Med Genet 1993;30:293-5). This case report of a female patient with genetically proven HD is of special interest because motor or cognitive impairment were absent whereas she suffered from symptoms of an acute and severe psychosis likely to be symptomatic signs of HD.