Pearls and Oy-sters: Huntington Disease Presenting as Primary Progressive Aphasia: A Case of Semantics.

We present a case of semantic variant primary progressive aphasia (PPA) as the presenting feature in a patient with Huntington disease (HD). The patient initially developed progressive language impairment including impaired naming, object knowledge and single word comprehension and then developed chorea and behavioural changes. Magnetic resonance imaging (MRI) of the brain showed left anterior temporal lobe and hippocampal atrophy. A neurological FDG PET/CT showed reduced metabolism in the head of the left caudate nucleus. Huntingtin gene testing revealed an expansion of 39 CAG repeats in one allele. This case outlines the substantial overlap between the clinical presentation of HD and frontotemporal lobar degeneration (FTLD) syndromes and provides commentary on the investigation of these neurodegenerative diseases.