Case presentation
The patient was a 75-year-old woman (II-6). On her first visit to our hospital at the age of 75 years, Huntington’s disease was suspected because she exhibited chorea in the neck and upper limbs and her family history included Huntington’s disease. Therefore, with the patient’s consent, genetic testing was performed; the results revealed a repeat abnormality of the HTT gene; thus, she was diagnosed as Huntington’s disease. The psychological test results were as follows: 25 points on the Mini-Mental State Examination and 10 points on the Alzheimer’s Disease Assessment Scale-Cognitive Subscale. Tetrabenazine, the only drug capable of preventing chorea movement, was then administered, but nausea and fatigue necessitated the discontinuation of oral administration. The patient’s older brother (II-5) who developed the disease at the same age as her had chorea that rapidly progressed; 5 years later, he was almost immobile and bedridden (Fig1).
Magnetic resonance imaging of the head showed changes in the striatum. In a cerebral blood flow test (IMP-SPECT), decreased blood flow was observed in the precuneus (anterior wedge) and posterior cingulate gyrus (Fig. 2). Usually, such areas of decreased blood flow are observed in Alzheimer-type dementia patients. We suspected Alzheimer-type dementia complications based on SPECT results of patient.
Initially, donepezil administration was considered, but because the patient was irritable, a regimen of low-dose memantine (5 mg/day) was started. Thereafter, swallowing and oral symptoms improved. Five years since then, clinical symptoms have not worsened. Involuntary movements also have not worsened substantially, and we have recorded the patient’s gait videos at the age of 75 and 80 years (Video1A and 1B). The patient did not show progression in gait speed and balance. Also after 5years, IMP-SPECT revealed improved blood flow image in front-temporal lobe. Additionally, information provided by family members and medical examinations by physicians specializing in rehabilitation did not reveal deterioration in the swallowing function or a decrease in the activities of daily living.