The first signs of the diseases in the neuroacanthocytosis (NA)
group are subtle and easily overlooked. Initial symptoms, which
often occur in the person’s mid 20’s, may include
grunts or tic noises made unconsciously in the throat, progressing
to drooling and problems in controlling the tongue from ejecting
food. Involuntary biting of the tongue, lips and/or cheeks may
At the beginning there can be a general, slight physical
awkwardness. Things on a shelf are knocked off for no apparent
reason. Difficulty with walking and balance can also be early
symptoms. Problems controlling trunk, leg and arm movements are
often barely noticeable at the beginning, but become increasingly
difficult as the disease progresses. Several patients find it
difficult to sleep at night and others report fatigue and weakness.
Personality change may also be an early indication. The carefree
young adult becomes obsessive-compulsive and uncharacteristically
forgetful or just loses confidence or drive. Fainting or epileptic
seizures may also occur. Mood changes may happen and a person often
becomes isolated, in part out of embarrassment.
There are several reports of the problems beginning after a
traumatic event including physical attack, unexpected failure of an
exam and birth of a child.
A defining symptom that is not apparent is the spiky red blood
cells, or acanthocytes, from which the NA disease group takes its
name. These unusual blood cells can be observed with a microscope
in some circumstances. Still more difficult to observe are the
alterations or mutations in patients’ genes. Each of the NA
group diseases has a different genetic characteristic that can be
determined only by blood tests.
A person showing some of this pattern of symptoms should see a
neurologist. Clinicians and patients can also visit www.naadvocacy.org
for links to further scientific reports. Full details are also
available on the free blood testing service offered by the Advocacy
for Neuroacanthocytosis Patients, aimed at helping determine a
definitive diagnosis for NA.
:: Useful NA
Neuroacanthocytosis Syndromes II, published December
2007, the book provides a profound insight into recent
developments within the field of neuroacanthocytosis syndromes.
Edited by Ruth H. Walker, Shinji Saiki and Adrian Danek.
Available at amazon.com
A Western blot test for the presence of chorein in the
membranes of red blood cells can be offered free of charge due to
support of the Advocacy for Neuroacanthocytosis Patients'.
Download instructions on the blood sampling and specimen shipment
as a PDF
or get more information on the method at PubMed
The entry for chorea acanthocytosis in GeneReviews
is the most complete, readily available report on ChAc. Published
by the University of Washington with the support of the National
Institutes of Health
A dedicated Patient & Families Support Group at Yahoo
Groups offers patients and families information, advice,
support or just an understanding ear
Visit PubMed for access to NA
research in English from the Medline database.
Visit the NA page on WeMove,
the Movement Disorder Societies charitable and educational
naadvocacy.org is the website of the The Institute
for Neuroacanthocytosis. It is the Advocacy's international
centre for supporting patients and promoting clinical and basic
research. The website provides access to resources found on
Orphan diseases aren't forgotten: a roadmap for rare diseases with EURORDIS
Maria Mavis & Glenn Irvine
Expertly managed by EURORDIS, the Paris-based European advocacy representing rare diseases, the summer school is based in Barcelona and aims to prepare patient organisations for their important role in initiating, encouraging and supporting drug development. The course is part of the wider work of EURORDIS, which provides a valuable link to the European Commission and the European Medicines Agency as well as national medical authorities.
Only 40 representatives of patient advocacy groups are chosen each year for the course, which offers all participants the opportunity to meet people intensely involved with "their" disease, who share insights and experiences as well as their shared empathy. The course also gives real focus and reason for hope to groups like the Advocacy, as it reveals the frameworks and commercial incentives that exist for the development of drugs for orphan diseases.
How are drugs and therapies for rare diseases tested and approved?
The course began with an introduction to medical research and the regulatory process that tests drugs and other therapies for safety and efficacy. The vital principle is that medicines will be approved only when sound clinical trials conducted according to ethical principles provide convincing, objective evidence of the positive effect of a drug.
The gold-standard for such trials is randomised, blind trials that include a large enough group of patients to give statistically significant results, but in rare diseases there may often be too few available patients to give statistically significant results. Trials of drugs for rare diseases with few patients available may use “cross-over” trials that compare a patient trial group taking the drug with a similar group taking a placebo, then after an agreed period the status of each group is exchanged.
When neuroacanthocytosis research produces drugs to be tested, the NA Patient Case Registry that we are building in conjunction with the European Huntington’s Disease Network will be a very important source of possible participants in the trials.
Special authorisations and incentives for the development of orphan drugs
The course also included valuable units on statistical analysis, especially as it relates to rare diseases. Risk is always present and preparations must be made to manage the element of risk contained in every trial. In some cases compassion may allow the use of drugs that have not been fully tested and approved when there is no alternative for a chronic rare disease sufferer. For diseases that are so rare that it cannot be expected that comprehensive evidence can be provided, short-term authorisation may be granted subject to certain obligations related to close monitoring of the safety of the drug. This may apply to the NA diseases.
The training went on to introduce the structure of drug approval and the collaboration between the European Medicine Agency and patient advocacy groups. Incentives for the development of orphan drugs exist.
EURORDIS – ongoing work to bring patient groups and drug development together
The EURORDIS Charter for Clinical Trials in Rare Diseases is in place to foster and control the collaboration of patient groups and the sponsors of new drugs.
The course was valuable training that arms the Advocacy with an insight into the path ahead, as our basic research identifies the causes of neurodegeneration in NA patients and seeks therapies to overcome or lessen causes.
Our thanks to the EURORDIS President, Yann Le Cam, Professor Josep Torrent-Farnel, the charismatic Catalonian organiser of the Summer School and Maria Mavris, the very effective administer of the event.