What is Huntington disease?
Huntington disease is an inherited neurologic disorder characterized by progressive neurodegeneration resulting in abnormal movements (chorea), sustained postures (dystonia), psychiatric symptoms, and dementia. The condition most frequently affects individuals during mid-life, but patients range from childhood to age 80. Symptoms are typically insidious – they come about slowly and progressively.
Chorea is described as a dance-like, rapid, involuntary, movement. Many patients often develop slow or rigid movements over time. They also typically have associated irritability, depression, and anxiety. In advances stages of the disease, patients eventually lose the ability to take care of themselves …show more content…
• How is Huntington disease diagnosed?
• How is Huntington disease treated?
What causes Huntington disease?
Huntington disease is typically acquired as a genetic disorder. The characteristic genetic abnormality is trinucleotide repeat expansion of CAG in the HTT gene. In other words, genetically acquired DNA mutations result in abnormal function of the HTT gene, resulting in progressive neurodegeneration.
Brain degeneration often affects a region called the caudate nucleus, which is part of the basal ganglia – this structure is critical for performing smooth motor movements. Injury to this region of the brain leads to motor abnormalities such as chorea, dystonia, and muscle rigidity.
How common is Huntington disease?
Huntington disease is a relatively uncommon disease that often requires referral to a neurology specialist, especially in atypical cases or if first-line treatment is ineffective.
Worldwide, the prevalence of Huntington disease is approximately 2.7 per 100,000 persons. Internationally, the incidence is about 0.38 per 100,000 persons per year. Huntington disease has a prevalence of 5.7 per 100,000 persons in Europe, North America, and Australia. Less than 10% of patients develop the disease prior to age …show more content…
Executive function such planning and organizing is frequently compromised. Patients with severe Huntington disease have a high rate of mortality.
How is Huntington disease diagnosed?
The diagnosis of Huntington disease depends on typical symptoms and clinical features, as well as a family history of the condition. Only a small percentage of patients have no family history of the disease.
Patients with a suspected diagnosis typically undergo confirmatory genetic testing for CAG trinucleotide repeats in a gene called HTT. Your doctor may also order an MRI of the brain, as well as laboratory tests to rule out other conditions that can mimic Huntington disease. A key characteristic finding on brain MRI is shrinkage or atrophy of the caudate – a region of the brain that is important for the pursuit of smooth, purposeful, movements.
Commonly ordered blood tests include a CMP (comprehensive metabolic panel), CBC (complete blood cell count), thyroid function studies (TSH, free T4), and vitamin B12 level. Your doctor may consider additional testing for HIV or syphilis based on you risk factors for sexually transmitted infection.
How is Huntington disease