Huntington's Disease

Huntington's disease or Huntington's chorea (HD) is an inherited disorder characterized by abnormal body movements called chorea, and loss of memory. It takes its name from the Ohio physician George Huntington who first described it precisely in 1872. The incidence is 5 to 8 per 100,000.

There is evidence that doctors as far back as the Middle Ages knew of this devastating disease.

Symptoms

Symptoms of the disorder include loss of cognitive ability (thinking, speaking), changes in personality, jerking movements of the face and body in general and unsteady walking. These symptoms develop into dementia and cognitive decline (not mental retardation which is an older term referring to the lack of development of mental ability rather than loss of it) and an advanced form of rapid jerking called chorea, the Greek word for dance.

The symptoms of Huntington’s disease begin insidiously. One-half to three-fourths of the patients present with abnormal movement or rigidity. The remainder of the patients present with mental status changes, such as irritability, moodiness, or antisocial behavior. Most of the patients eventually exhibit chorea, which is jerky, random, uncontrollable, rapid movements. Typically, the abnormal movements begin at the extremities and then later progress.

Diagnosis

Symptoms of Huntington's disease begin increasingly early the more glutamines a person carries within the repeating portion of his or her mutant huntingtin proteins. This number increases as the disease gene is passed on, so that the age of onset decreases with successive generations (although not infinitely early, since patients with childhood symptoms tend not to have children themselves).

The diagnosis is established by neurological examination findings and/or demonstration of cell loss, especially in the caudate nucleus, supported by a cranial CT or MRI scan findings