Juvenile-HD

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SECTION 1 - AT RISK
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SECTION 3 - JHD
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SECTION 4 - SYMPTOM RECOGNITION
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Chorea
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Denial of HD
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-Read If Your Child Is On Antidepressant
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-Seizures ~Special Populations
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SECTION 5 - COMMUNICATION
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Communication Strategies For HD~Jeff Searle
SECTION 6 - EATING/SWALLOWING/NUITRITION
Hints For Weight Loss in HD
HD & Diet~HSA Fact Sheet 7
Nutrients: Some Possible Deficiency Symptoms
Nutrition and HD~Anna Gaba (Recipes)
Nutrition Information In HD~Naomi Lundeen
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Swallowing & Nutrition Physician's Guide To HD
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5 Swallowing Problems
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-Feeding Tubes~Advanced Stages of HD
-Feeding Tube~Jean Miller
-Feeding Tubes: One More Word ~Jean Miller
-Feeding Tubes & Baby Foods
-Feeding Tube~Dental Care
-Feeding Tube Instructions~Jean Miller
-Feeding Tube Resources
SECTION 7 - THERAPIES
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SECTION 8 - MEDICATIONS
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-Adolescents Under 25
-Antidepressant Adverse Effects
-Anti-psychotic
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-Creatine
-EPA~Fish Oil
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-Haldol~Clinician Description
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-Neuroleptic Malignant Synd WARNING
-Olanzipine-Risperidone/blood tests
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-Psychiatric Drugs & Children
Sertraline ~Zoloft
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-Sites/Help the Medicine Go Down
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SECTION 9 - SURGERIES
Surgery-Movement Disorders
o Surgery Resources
SECTION 10 - PROCEDURES
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SECTION 11- ALCOHOL/DRUGS
Alcohol-Parent's Guide
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Drugs-Talking To Your Child
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SECTION 12- SUICIDE
Straight Talk On Suicide
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o Suicide Resources
SECTION 13 - DIVORCE
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SECTION 14 - DISABILITY ISSUES
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SECTION 15 - ASSISTIVE TECHNOLOGY
Child Assistive Technology
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Products
SECTION 16 - EMOTIONAL ISSUES
Signs of Unhealthy Self-Esteem
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o Emotional Support Resources
SECTION 17 - GRIEF
Helping Child Deal With Death
o Grief Addtional Resources
SECTION 18 - ADD/ADHD
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What Is AD/HD?
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SECTION 19 - HD SUPPORT GROUPS
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SECTION 20 - HD LINKS
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SECTION 21 - BENEFITS/INSURNACE
HD Disability
Benefits Check UP - See What You Can Get
Medical Insurance Bureau's Facts On You!
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No Insurance? Try This!
Prescription Drug Cards Part I
Prescription Drug Cards Part II
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SECTION 22 - ARTICLES/JHD
JHD and ADD
SECTION 23 - CAREGIVING
Articles-Resources
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"First Shift With A Person With HD"
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SECTION 24 - BIO
Our Personal Experience
Coping At The End
Kelly E. Miller
Song & Verse
Letter From My Heart
GUESTBOOK
Chorea-Physician's Guide

INDEX Page

 
HD~Chorea
 
The Physician's Guide to The Management of HD
http://hdlighthouse.org/see/index.html?pg2/0.htm

OVERVIEW The movement disorder is characterized both by the emergence of involuntary movements, or chorea, and by impairment of voluntary movements. This latter impairment often contributes more to disability than the chorea itself, resulting in reduced manual dexterity, slurred speech, swallowing difficulties, problems with balance, and falls.

Both chorea and impairment of voluntary movements progress in the middle stages of HD, but later, chorea often declines as patients become rigid and unable to initiate voluntary movements. Patients in this advanced state are unable to care for themselves.

INTRODUCTION - There are two parts to the movement disorder associated with Huntingtons disease: the presence of involuntary movements, and the impairment of voluntary movements. The involuntary movements are called chorea, or choreoathetosis, and consist of irregular jerking or writhing movements. Chorea is the most noticeable feature of HD.  In fact, the condition is often referred to as Huntington's Chorea , yet the impairment of voluntary movement is more highly corelated with functional disability.

Abnormal eye movements (interrupted pursuit and slow, hypometric saccades), slow and uncoordinated fine movements, dysarthria, gait disturbance, and dysphagia can be largely independent of chorea and may limit a person's movement disorder, cognition, or mood. ability to work, care for himself, and communicate.

Although it is tempting to treat the highly noticeable chorea of Huntington's disease right away, it is important to remember that the drugs used to suppress chorea can have disadvantages of their own, including worsening of voluntary motor disturbance.

TABLE2: PRINCIPLES OF TREATMENT
OF THE MOVEMENT DISORDER

  • Consider non-drug interventions first.
  • Pharmacologic treatment of chorea
    may worsen other aspects of the
    movement disorder, cognition or mood.
  • Chorea may diminish over time,
    reducing the need fortreatment.

 

 

 

 

 

 

Chorea
Many patients are not bothered by their chorea and may not even be aware of most of the movements. The physician and patient first need to establish whether the chorea requires any treatment at all. Is the chorea severe enough to interfere with voluntary activities such as writing, cooking, or eating? Does severe chorea seem to be causing falls or accidents? Is highly visible chorea a significant source of distress for the patient?

Before beginning medication for chorea, non-pharmacologic interventions should be considered. Chorea, like most forms of involuntary movement, is worsened by stress, anxiety, or depression, is decreased during sleep, and often varies with posture or positioning. Treatment of underlying mood and anxiety disorders, and providing a calm, predictable environment are a first step.

Various assistive devices may be helpful. These include padded, reclining chairs, padding for the bed, and wrist and ankle weights to reduce the amplitude of the chorea. Sources for some of these devices are provided in Appendix 3.

Doctor and patient also need to have realistic expectations for pharmacotherapy. Medications will not alter the progression of the underlying illness. They will not improve speech or the ability to swallow, prevent falls, or improve fine motor control. In fact, drug-related side effects such as sedation and rigidity may increase the risk of falls and decrease the intelligibility of speech. However, reduction of severe chorea may improve gross motor control and may be of cosmetic value.

Akathisia is an extremely uncomfortable internal sense of restlessness, sometimes induced by neuroleptics, which may cause patients to pace, or be unable to sit still. It can be mistaken for agitation or anxiety, prompting the physician to increase the dose of the offending drug, creating a vicious cycle.

The movement disorder of HD changes over time. In most patients chorea eventually peaks and then begins to decline, while rigidity and bradykinesia become more significant. At this point, the drugs that helped to suppress chorea may no longer be needed, and in fact may worsen HD-related rigidity. Therefore it is important to assess the need for anti-chorea medication at regular intervals, and perhaps to make periodic trials of dose reduction or discontinuation.

TABLE 3: MEDICATIONS USED TO SUPRESS CHOREA
CLASS MEDICATION STARTING DOSE MAXIMUM DOSE ADVERSE EFFECTS
Neuroleptics
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Benzodiazepines
 
 
 
 
 
Dopamine Depleting
Agents
Haloperidol
 
 
 
 
 
 
 
Fluphenazine
 
Risperidone
 
Thiothixene
 
 
 
Thioridazme
 
 
Clonazepam
 
 
 
Diazepam
 
Reserpine
 
 
Tetrabenazine
0.5-lmg/day
 
 
 
 
 
 
 
0.5-lmg/day
 
0.5-lmg/day
 
l-2mg/day
 
 
 
l0mg/day
 
 
0.5mg/day
 
 
 
1.25mg/day
 
0.lmg/day
 
 
25mg/day
6-8mg/day
 
 
 
 
 
 
 
6-8mg/day
 
6mg/day
 
10-20mg/day
 

 
l00mg/day
 
 
4mg/day
 
 
 
 20mg/day
 
3mg/day
 
 
l00mg/day
sedation,
parkisonism,
dystonia, akathisia,
hypotension,
constipation,
dry mouth,
weight gain
 
same
 
less parkinsonism
 
less parkinsonism,
more sedation and
postural hypotension
 
similar to
thiothixene
 
sedation, ataxia,
apathy, withdrawal
seizures
 
same
 
hypotension,
sedation,depression
 
less hypotension

 

Three classes of medication are commonly used to suppress chorea in Huntington's disease: neuroleptics, such as haloperidol and fluphenazine; benzodiazepines, such as clonazepam and diazepam; and dopamine depleting agents, such as reserpine and tetrabenazine. Each class has its advantages and disadvantages.

The suppression of movement, regarded as a side effect when neuroleptics are used to treat psychosis, is the desired effect when they are used to treat chorea. Therefore the most popular neuroleptic agents are the high potency drugs, which can also induce the most parkinsonism.

Haloperidol and fluphenazine are most commonly prescribed. They should be started at a low dose, 0.5 to lmg once or twice a day, and gradually increased to efficacy. Doses higher than 6-8mg per day have not generally been found helpful in treating chorea.

Risperidone is a newer neuroleptic which does not cause as much parkinsonism as the other high potency agents, but is still useful in suppressing chorea and may relieve agitation as well. It may be also be started at 0.5-lmg once or twice a day, with some patients tolerating doses as high as 6-8mg daily.

In some cases, patients who experience unacceptable rigidity, akathisia, or dystonia with high potency agents may benefit from a lower potency neuroleptic such as thiothixene or thioridazine. This may be preferable to adding an anticholinergic agent to the original drug to counteract the side effects.

Lower potency agents tend to be more sedating, however, and are more inherently anticholinergic, producing more tachycardia, postural hypotension, constipation, and delirium. Thiothixene can be started at l-2mg once or twice a day and increased to 10-20mg/day. Thioridazine, which is even lower potency, can be started at l0mg once or twice a day and increased to about l00mg/day.

Patients starting neuroleptics should be warned about two unlikely, but potentially serious adverse effects. The first is tardive dyskinesia, a syndrome of involuntary movements often first noted in the face and mouth, that develops in some patients taking neuroleptics. Tardive dyskinesia is of concern because the symptoms are usually permanent, and will likely be hard to recognize in someone with HD.

The other serious problem is neuroleptic malignant syndrome, a rare, but life threatening reaction characterized by acute onset of delirium, rigidity, and fever, often accompanied by leukocytocis, and elevated CPK. Families should know about this so that the patient can be given prompt medical attention if it develops.

Benzodiazepines, such as clonazepam and diazepam can also be useful in the treatment of chorea. Some clinicians prefer them to neuroleptics because they do not induce parkinsonism or tardive dyskinesia. Sedation and the increased risk of delirium are the main deleterious side effects, along with tolerance, withdrawal symptoms, and the potential for abuse.

Long acting varieties such as clonazepam and diazepam are favored because they require less frequent dosing, provide more even coverage of symptoms throughout the day, and are less likely to precipitate withdrawal symptoms if a dose is missed. Clonazepam may be started at 0.5mg per day, and may be raised as high as 4mg per day, in divided doses. Diazepam may be dosed from about 1.25mg to 20mg per day, also in divided doses.

Some clinicians favor dopamine depleting agents as a treatment for chorea. While these drugs do share some of the "neuroleptic" side effects, they may be milder at low doses, and they have not been shown to cause tardive dyskinesia. The class includes reserpine and tetrabenazine, which is not sold in the United States, but is used widely in Europe.

Reserpine was used in the past as an antihypertensive, and may cause hypotension. This can be minimized by giving the drug at bedtime. Parkinsonism, restlessness, dizziness, and sedation are other common side effects. The increased rate of depression in patients taking these agents is also of concern. Reserpine may be started at 0.lmg per day and increased weekly to a dose as great as 3mg per day.

Tetrabenazine is similar in action to reserpine, but is felt by some clinicians to be more effective and is less likely to cause hypotension. It can be started at 12.5mg bid or tid and increased over several weeks to a maximum of 75 or l00mg per day in divided doses. Tetrabenazine may be obtained from John Bell & Croyden in the UK by calling 011-44-171-935-5555 or faxing a prescription to 011-44-171-935-9605. The drug is costly and probably will not be covered by insurance.


_____________________________________________________________________
 
Other Information
 
HDL article http://hdlighthouse.org/see/care/chorea.htm
Conclusions:
Patients with Huntington disease have impaired subjective experience of chorea. Denial of symptoms is likely to have a physiological basis and is not a secondary consequence of patients' cognitive impairment or a psychological defense against a debilitating disease.
_____________________________________________________________________
 

Huntington's Chorea
Authored by J. Stephen Huff, MD, Associate Professor, Departments of Neurology and Emergency Medicine, University of Virginia Health Sciences Center CME
 
Question 2: What is the best treatment for symptoms of chorea in HD?

A: Haloperidol
B: Clonazepam
C: Beta-blockers
D: Carbamazepine
E: Reassurance

The correct answer is E: Chorea may be suppressed with drugs but is seldom worth the associated side-effects. Most patients are actually untroubled by the choreic movements. Suppression of the movements usually does not result in improved function.
_____________________________________________________________________
 

Subject: Tetrabenazine for Huntington's Disease (AAN 2001)
Date: 5/8/01
http://www.wemove.org/emove/article.asp?ID=319
Tetrabenazine can improve chorea in HD for up to a year, according to this study.

Adverse effects included akathisia, constipation, drooling, and insomnia, most of which resolved with dose adjustment.
_____________________________________________________________________
 

Subject:
Symptomatic Effect of Lamotrigine in HD
Date: 10/1/99
http://www.wemove.org/emove/article.asp?ID=116
Lamotrigine does not slow Huntington's disease progression, but can improve symptoms and may lessen chorea, according to this double-blind study.

Lamotrigine ABSTRACT
Influence of lamotrigine on progression of early Huntington disease
A randomized clinical trial

CONCLUSIONS: There was no clear evidence that lamotrigine retarded the
progression of early Huntington disease over a period of 30 months. However, more patients on lamotrigine reported symptomatic improvement (53.6 versus 14.8%; p = 0.006), and a trend toward decreased chorea was evident in the treated group (p = 0.08).

BRAND NAMES: Lamictal
FAQ: Lamotrigine for Depression and/or Mania.
http://chem-faculty.ucsd.edu/harvey/lamotrigineinfo.htm
FAQ: Lamotrigine for Depression and/or Mania.
http://www.psycom.net/depression.central.lamotrigine.html
Anticonvulsant Medication-Medscape users:
http://promini.medscape.com/drugdb/drug_class.asp?DrugCode=1%2D7378&DrugName=LAMOTRIGINE+ORAL&DrugType=1

WARNING: One Mom's JHD  son was put on this and had a severe increase in his myoclonus, to where he was completely unmanagable.  Very scary.
________________________________________________

Brain SPECT imaging in Huntington's disease before and after therapy with olanzapine. Case report.

Arq Neuropsiquiatr 1999 Sep;57(3B):863-6   (ISSN: 0004-282X)

Etchebehere EC; Lima MC; Passos W; Maciel Junior JA; Santos AO; Ramos CD; Camargo Department of Radiology, Faculdade de Ciencias Medicas (FCM) da Universidade Estadual de Campinas (UNICAMP), Brazil. elba@mn-d.com

Olanzapine, an atypical antipsychotic drug, was administered to a patient with Huntington's disease (HD) with marked choreiform movements. Brain SPECT with 99mTc-HMPAO was performed before and after treatment.

Brain SPECT imaging has been performed in patients with HD in order to determine the status of basal ganglia perfusion. The use of brain SPECT with 99mTc-HMPAO before and after treatment in patients with HD has not been yet reported.

The marked hypoperfusion of the basal ganglia on brain SPECT performed before therapy with olanzapine improved significantly after treatment.

Major Subject Heading(s) Minor Subject Heading(s) CAS Registry / EC Numbers
  • Antipsychotic Agents [therapeutic use]
  • Brain [radionuclide imaging]
  • Huntington Disease [drug therapy]
  • Pirenzepine [analogs & derivatives]
  • Tomography, Emission-Computed, Single-Photon
  • Adult
  • Huntington Disease [radionuclide imaging]
  • Pirenzepine [therapeutic use]
  • Radiopharmaceuticals [diagnostic use]
  • Technetium Tc 99m Exametazime [diagnostic use]
  • 0 (Antipsychotic Agents)
  • 0 (Radiopharmaceuticals)
  • 0 (Technetium Tc 99m Exametazime)
  • 132539-06-1 (olanzapine)
  • 28797-61-7 (Pirenzepine
  • _____________________________________________________________________
    Chorea in Children
     
    See above site for full article.  Following specific on JHD:
     
    JUVENILE HUNTINGTON DISEASE  

    Introduction

    Huntington chorea is an autosomal-dominant, neurodegenerative disorder in which chorea is a primary clinical manifestation. Other prominent clinical features include progressive cognitive decline and an array of psychiatric disturbances.

    The average age of onset is at 35-40 years; however, the disease has been reported in children as young as 4 years.

    • The age of onset varies among families, with some showing consistently older age of onset than others.

    • Age of onset among individuals of the same family also can vary widely; children of an affected father may have a younger age of onset than children of an affected mother.

    The term "juvenile Huntington disease" designates patients whose clinical manifestations begin before the age of 20 years. This group also may be divided further into those with onset before the age of 10 years and those with onset in adolescence.

    Genetics

    Huntington disease (HD) is an autosomal-dominantly inherited disease with complete penetrance. The responsible gene, IT-15, is located on the p16.3 subband of chromosome 4. The genetic mutation is an unstable, expanded DNA trinucleotide (cytosine-adenosine-guanosine or CAG) repeat within the coding region for a 348-kD protein named huntingtin.

    • All individuals possess this repeat sequence; it is the number of triplet repeats that is significant. Patients with HD have 38 or more repeats. The earlier the age of onset, the greater the number of repeats for a given individual.

    • The correlation between repeat length and rate of disease progression is unclear. Approximately 10% of HD gene carriers develop signs of illness before age 20 years.

    • Between 70% and 80% of patients with childhood-onset HD have inherited the gene from an affected father.

    • Note that as many as 1% of individuals with HD may have a negative test result.

    Clinical features

    HD in childhood presents with a slightly different constellation of symptoms than the adult form. The former presents with rigidity, a conspicuous slowing of eye movements from loss of rapid saccadic eye movements, and occasionally seizures as early features. It can also present as difficulty in school, even before clinical signs relating to the movement disorder become apparent.

    • The patient may appear to be primarily clumsy, rather than either rigid or choreiform.

    • Reflexes are usually brisk, and pyramidal signs with extensor plantar responses are common.

    • Seizures occur in about 30-50% of patients; they usually appear late in the disease and are difficult to control.

    Diagnosis

    The availability of a DNA-based testing (to reliably identify the HD mutation) greatly facilitates diagnosis of the disease. Prior to direct DNA testing, clinical findings and family history were the cornerstones of diagnosis.

    Brain MRI in juvenile HD usually demonstrates striatal hyperintensity on T2-weighted images (a feature that is not present in most hyperkinetic patients with HD), indicating greater striatal damage.

    Presymptomatic testing should be executed only under rigid guidelines.

    • It should be performed only at the request of the patient.

    • Test results should be released only to the patient; if the result is to be released to another party, written consent is required from the patient.

    • Testing minors is considered inappropriate at this time, because results may have significant negative repercussions in raising the child.

    Treatment

    Presently, no specific therapy is available for HD. Management consists of symptomatic therapy and counseling.

    • Some patients benefit from antidepressants; carbamazepine may be useful for mood swings.

    • Agents used to treat symptoms of bradykinesia and rigidity, such as L-dopa or directly acting dopamine agonists, can be helpful but often exacerbate chorea and provoke hallucinations and psychosis.

    Experimental therapies (eg, agents that improve mitochondrial energy metabolism, agents that attenuate glutamate neurotransmission and free radical scavengers) have been ineffective.