Huntington's Disease
From WikiGenetics
Contents |
[edit] Name of Condition
Huntingon's Disease (HD)
[edit] Definition
Huntington's Disease: a devastating, hereditary, degenerative brain disorder for which there is, at present, no effective treatment or cure. HD slowly diminishes the affected individual's ability to walk, think, talk and reason. Eventually, the person with HD becomes totally dependent upon others for his or her care. Huntington's Disease profoundly affects the lives of entire families -- emotionally, socially and economically.
[edit] Description, Signs and Symptoms
Early symptoms of Huntington's Disease may affect cognitive ability or mobility and include depression, mood swings, forgetfulness, clumsiness, involuntary twitching and lack of coordination. As the disease progresses, concentration and short-term memory diminish and involuntary movements of the head, trunk and limbs increase. Walking, speaking and swallowing abilities deteriorate. Eventually the person is unable to care for him or herself. Death follows from complications such as choking, infection or heart failure.
Symptoms usually evolve slowly vary from person to person, even within the same family. Some individuals may be affected first cognitively (depression, forgetfulness, impaired judgment). Others suffer with motor skill impairment (dystonia or involuntary movements, unsteady gait). Eventually, every person afflicted by HD requires full-time care.
Domains affected include: cognitive, motor and behavioral. Members of the same family may exhibit different symptoms. Some can show mild involuntary movements (chorea) and have more emotional/behavioral symptoms of HD or can have less emotional/behavioral symptoms with more difficulty with involuntary movements.
Some HD Symptoms:
Behavioral/emotional
Irritability
Depression
Anxiety
Aggressive outbursts
Mood swings
Social withdrawal
Motor
Fidgety behavior
Uncoordination
Involuntary movements (chorea, dystonia)
Difficulties with speech, swallowing, balance, walking
Cognitive
Problems with short-term memory, organizing, coping, concentrating
Stages of HD
Although symptoms of HD vary from person to person, even within the same family, the progression of the disease can be roughly divided into three stages.
Early Stage HD usually includes subtle changes in coordination, perhaps some involuntary movements (chorea), difficulty thinking through problems and often, a depressed or irritable mood. Medications are often effective in treating depression or other emotional problems. The effects of the disease may make the person less able to work at their customary level and less functional in their regular activities at home.
In the Middle Stage, the movement disorder may become more of a problem. Medication for chorea may be considered to provide relief from involuntary movement. Occupational and physical therapists may be needed to help maintain control of voluntary movements and to deal with changes in thinking and reasoning abilities. Diminished speech and difficulty swallowing may require help from a speech language pathologist. Ordinary activities will become harder to do.
In the Late Stage, the person with HD is totally dependent on others for their care. Choking becomes a major concern. Chorea may be severe or it may cease. At this stage, the person with HD can no longer walk and will be unable to speak. However, he or she is generally still able to comprehend language and retains an awareness of family and friends. When a person with HD dies, it is typically from complications of the disease, such as choking or infection and not from the disease itself.
In all stages of HD, weight loss can be an important complication that can correspond with worsening symptoms and should be countered by adjusting the diet and maintaining appetite.
[edit] Inheritance
Each child of a person with HD has a 50/50 chance of inheriting the fatal gene. Everyone who carries the gene will develop the disease.
[edit] Demographics
One out of every 10,000 Americans has HD. Yet the devastating effects of HD touch many more. HD does not skip generations.
Each child of a parent with HD has a 50/50 chance of inheriting the gene that causes HD.
If a child does not inherit the gene, he or she cannot pass it on. If the child does inherit the gene, he or she can pass it on and will develop the disease if that child lives long enough. More than a quarter of a million Americans have HD or are "at risk" of inheriting the disease from an affected parent. HD affects as many people as Hemophilia, Cystic Fibrosis or muscular dystrophy.
HD typically begins in mid-life, between the ages of 30 and 50, though onset may occur as early as the age of 2. Children who develop the juvenile form of the disease rarely live to adulthood. HD affects males and females equally and crosses all ethnic and racial boundaries.
[edit] Diagnosis
In 1993, the HD gene was isolated and a direct genetic test developed which can accurately determine whether a person carries the HD gene. The test cannot predict when symptoms will begin. However, in the absence of a cure, some individuals "at risk" elect not to take the test.
[edit] Treatment and Management
Research has yet to find a means of curing or even slowing the deadly progression of HD although some medications can relieve some of the symptoms in certain individuals.
Research efforts are currently exploring many new avenues and approaches including focus on way to delay onset of HD, development of effective therapies that may slow the progression of HD and ultimately, a cure for the disease.
[edit] Prognosis
At this time, there is no way to stop or reverse the course of HD. There is no treatment to halt the progression, which leads to death after ten to twenty-five years. However, now that the HD gene has been located, investigators are continuing to study the HD gene with an eye toward understanding how it causes disease in the human body.
[edit] Resources
AccessDNA.com - Huntington's Disease[1]
Hunginton's Disease Society of America
