Chorea huntington

Huntington’s Chorus: description

Huntington’s is a very rare hereditary disorder of the brain. It is estimated that approximately seven to ten out of every 100,000 people in Western Europe and North America are affected. In Germany, approximately 8,000 people suffer from Huntington’s disease.

Huntington’s disease can break out at any age. The first symptoms of Huntington’s disease often appear between the ages of 35 and 45 years, but can also occur in early childhood or only in old age. This also depends on exactly where the disease-causing change (mutation) in the genome lies. Typical symptoms include movement disorders and changes in nature to dementia.

The influence on the course of Huntington’s disease is limited. A large number of substances have been tested to protect the nerve cells and stop the progressive neuronal degeneration. So far, however, none of these substances has been able to have a significant effect on the course of the disease. However, there are some medications available that can help reduce the chorea symptoms of Huntington’s disease.

There are support groups that help people with Huntington’s disease and their relatives.

Where the name “Chorea Huntington” comes from

The Huntington Hunt comes from the US doctor George Huntington, who first described the disease in 1872. He also recognized that Huntington’s disease is inherited. The name comes from the Greek – “choreia” = “dance”. The Huntington’s Chorus has several names: Huntington’s disease, Huntington’s disease or earlier also Veitstanz. The reason is that the patients gradually lose control of their movements – which remotely reminds of a dance.

Huntington’s disease: symptoms

Huntington’s chorea: early stage

Huntington’s disease often begins with nonspecific symptoms, such as mental abnormalities, which continue to progress. Many patients are increasingly irritable, aggressive, depressed or uninhibited; others feel a loss of spontaneity or an increasing anxiety.

The movement disorders in Huntington’s disease usually consist in sudden, involuntary movements of the head, hands, arms, legs or trunk. In extreme cases, this can lead to a disease-typical prancing course. Therefore, Huntington’s disease was formerly called “Veitstanz”.

People with Huntington’s disease can often incorporate these exaggerated and unwanted movements in their movements at first. For the observer, this creates the impression of an exaggerated gesture. In many cases, those affected do not initially notice their movement disorders as such.

Huntington’s Huntington: Later stages

As Huntington’s disease progresses, the tongue and throat muscles are also increasingly affected. The language seems choppy, sounds are expelled explosively. Also, swallowing disorders are possible – then there is a risk that those affected swallow food components and develops pneumonia.

As Huntington’s disease progresses, patients often lose their mental faculties inexorably. After about 15 years, dementia can be proven in nearly all affected persons.

In the final stages of Huntington’s disease, patients are usually bedridden and completely dependent on the help of others.

Huntington’s disease – similar diseases

Symptoms similar to those of Huntington’s chorea can also be caused by other non-hereditary causes. Examples are the consequences of infectious diseases or a hormone change in pregnancy (chorea gravidarum). Medications and hormonal contraceptives (like the pill) are rarer triggers. This also applies to strokes that affect certain regions of the brain. Due to circulatory disorders in the brain, a form of chorea can occur even in old age. It is believed that even diseases such as hyperthyroidism can lead to a chorea. The course is not progressing here, and the movement disorders usually recur. Severe mental symptoms are atypical in such cases.

Huntington’s disease: causes and risk factors

Huntington’s disease is caused by a genetic destruction of nerve cells in certain areas of the brain. The disease can affect both men and women, because the responsible gene is not inherited sex-linked – not on the sex chromosomes X and Y, but on the autosomes. These are those chromosomes that do not determine gender and are each available in two copies (one from the mother, one from the father).

Every child of a parent who carries the defective gene has a 50% risk of getting the defective gene and also suffering from Huntington’s disease. Experts speak of an autosomal dominant inheritance. Dominant means that the disease breaks out even if only on one of the two paired chromosomes the gene is altered.

Inheritance – Error on chromosome four

The molecular alphabet of the genetic material (deoxyribonucleic acid, DNA or DNA short) consists of four nucleic acids: adenine, thymine, guanine and cytosine. Always new combinations of these four letters form the entire genetic information, which is stored in the form of thread-like structures, the so-called chromosomes.

In Huntington’s disease, one gene on chromosome four is altered (also called Huntington’s gene). It was identified in 1993. The protein encoded by this gene does not function properly, eventually leading to the symptoms of Huntington’s disease.

In healthy people, the three nucleic acids cytosine-adenine-guanine are repeated 10 to 30 times in this region on chromosome four. With more than 36 cytosine-adenine-guanine repeats (CAG repeats or CAG triplets), chorea breaks out Huntington’s disease. 30 to 35 CAG repeats are considered gray areas.

In about one to three percent of sufferers, no blood relatives can be found with Huntington’s. Either it is a completely new gene change, a so-called new mutation. Or, a parent with Huntington’s disease has already had 30 to 35 repetitions and the disease did not break out with him. In the next generation, the number of repeats often increases. At more than 36, the children develop Huntington’s disease.

The more CAG repeats counted on chromosome four, the sooner does chorea break out and the disease progresses more quickly.

The neuronal desease in Huntington’s disease affects the cerebral cortex and especially the so-called Stammganglien. These are large nerve cell groups inside the two halves of the brain, which play a role in the coordinated course of movements.

Huntington’s disease: examinations and diagnosis

If it is suspected that you have Huntington’s disease, it is best to visit a specialized Huntington’s Center with experienced neurologists. Because family doctors and sometimes even “normal” neurologists have never seen a patient with this disease.

At the beginning of the diagnosis of Huntington’s chorea is a detailed survey, including the family history (anamnesis). Interesting for the doctor is whether close relatives (parents, grandparents) are ill with Huntington’s Disease. Also important for the diagnosis are the symptoms of chorea-Huntington’s disease (in the initial stage they may also indicate other diseases), the course of the disease and abnormalities in the neurological examination.

The diagnosis is confirmed by a blood test. The excessive number of repetitions of the same base pairs (CAGs) in a given gene on chromosome four can be detected by molecular genetic analysis.

If no genetic change is found, blood will be drawn again to rule out any conditions that may initially show symptoms similar to those of Huntington’s disease. Among other things, thyroid levels and the concentration of certain autoantibodies (antibodies that are directed against the body’s own substances) are determined in the blood.

Determine nerve damage

To determine the extent of nerve damage, people with Huntington’s disease are also being examined neurologically, neuropsychologically and psychiatry. These examinations are carried out either by experienced doctors or specially trained neuropsychologists.

Imaging studies like a Computed tomography (CT) or magnetic Resonance Imaging (MRI) of the brain can show the breakdown of individual areas of the brain (for example, the so-called tail nucleus and the cerebral cortex). Also the electrophysiological diagnostics may in some cases provide important information in Huntington’s disease.

Gene test on Huntington’s Chorea

Even healthy people with an increased risk of Huntington’s disease can have a genetic test done. Doctors speak of predictive diagnostics or predictive diagnostics. This study clearly identifies whether someone will contract Huntington’s disease or not.

However, this knowledge of being the carrier of this gene change can have a massive impact on the psyche of those affected. Therefore, there are guidelines for conducting a genetic test for Huntington’s disease. Among other things, the persons concerned must be informed in advance about the risks. In the case of minors, no genetic examination may be carried out. Not even with persons at the request of third parties, for example physicians, insurance companies, adoption agencies or employers.

Huntington’s Hunting: treatment

Huntington’s Huntington – medicines

Huntington’s can not be treated causally and is not curable. Certain medications, however, relieve the symptoms. Thus, the active ingredients tiapride and tetrabenazine can limit the excessive and uncontrolled movements by counteracting the body’s own messenger dopamine. In depressive disorders, antidepressants from the group of selective serotonin reuptake inhibitors (SSRIs) or sulpiride may reduce the symptoms.

There is no official therapy recommendation against the development of dementia in Huntington’s disease. In some studies, the active ingredient memantine could slow down intellectual decline.

In addition to drug-based Huntington’s disease therapy, supportive measures such as physiotherapy, occupational therapy and speech therapy can also help alleviate the symptoms. For example, special exercises can improve speech or swallowing disorders. In addition, the activities of everyday life can be trained with occupational therapy. This allows people with Huntington’s disease to stay independent for longer. Psychotherapy helps many sufferers to better deal with the disease. Self-help groups also represent a great support for many.

Since many people with Huntington’s Disease decline sharply in the course of their illness, a high-calorie diet makes sense. In some cases, slight overweight improves the symptoms of Huntington’s disease.

Huntington’s Chorea – Research

Therapies that could stem the underlying degradation process in Huntington’s chorea are not yet known. Many new approaches to drug-based chorea-HD therapy are being pursued, but they are still in the experimental stage. High doses of CoEnzyme Q10 have been shown to have slightly positive effects in studies, but overall they do not affect the course of the disease. CoEnzyme Q10 is a protein that occurs naturally in the body and protects the cells from damage.

Another drug for the treatment of Huntington’s chorea is ethyl icosapent, a drug specially developed for Huntington’s disease, which is made from the fish oil ingredient eicosapentaenoic acid. Ethyl icosapent is said to prevent the damage of certain cell constituents, which play a role in cell death, and to increase the efficiency of diseased nerve cells. Also this drug could cause no improvement in movement disorders.

Huntington’s disease: disease progression and prognosis

Huntington’s disease is not curable. The patients die on average 19 years after the onset of Huntington’s disease. It is only an average, which means that individuals may die much later or earlier as a result of Huntington’s disease.

The symptoms that people develop and how well they respond to the various drugs vary widely. With the many peculiarities of the disease are only sufficiently familiar to specialists who deal with Huntington’s daily. Therefore, it is recommended for Huntington’s patients to have themselves regularly examined in one of the Huntington centers in Germany in order to adapt the individual therapy to the current course of the disease.

For relatives and life partners of people with Huntington’s disease, the disease is emotional, sometimes financially very stressful. The German Huntington Hilfe e.V. helps families of those affected with valuable advice and important addresses as needed.