|
Ray D’Alonzo, Ph.D., is an Associate Director of Research and Development
at Procter & Gamble Pharmaceuticals where he has worked for 29 years and led
research programs in bone metabolism, infectious disease, respiratory
disease, arthritis, and nutrition. He has published scientific papers on a
wide variety of topics from the chemical composition of fats and oils to the
pharmacoeconomics of osteoporosis. Dr. D’Alonzo is the recipient of the
Chancellor’s Medal from the University of Massachusetts, Amherst, in part,
for his contributions to the development of new pharmaceutical agents. As
both a patient and scientist, he has made a personal effort to increase the
awareness of Chiari in the health care sector and to assist others afflicted
with the syndrome. He has published the story of his personal struggle
with Chiari in a book,
Contents Under Pressure,
with 100% of royalties going towards Chiari education, awareness, and
research programs.
May 20, 2006 --
The
duck-billed platypus (Ornithorhynchus anatinus) is a primitive
animal that lives in Australia and has anatomical characteristics of several
creatures that are strikingly diverse in their nature. It lays eggs and has
a bill like a duck. It
suckles its young like a mammal. It has a broad flat tail like a beaver.
It resembles a reptile in that it has cervical ribs and uses the same
opening for reproduction and the elimination of waste products. Like a
scorpion it possesses a spur for injecting threatening invaders with
poison. And, perhaps most unusual, like certain bony fish and some frogs,
it possesses the ability to sense electric currents propagated by certain
creatures that it likes to eat.
In chemistry,
there is an analogy. It’s element number 81, thallium. Thallium is a
metallic chemical element that was discovered in 1861. Dumas once called it
the "Ornithorhynchus paradoxus of metals”. Its physical properties
resemble that of lead’s. However, chemically it behaves like aluminum to a
large extent but with exceptions like forming univalent compounds similar to
sodium and potassium but a weakly basic oxide similar to manganese.
At this point, the reader may see where I am going. I like to think of
Chiari as the Ornithorhynchus impersonatus of human diseases. We
already know that Chiari is often misdiagnosed as clinical depression,
multiple sclerosis, fibromyalgia and chronic fatigue syndrome because so
many of its symptoms are similar to those diseases. But, it is really a
much more sophisticated situation. Like Tony Curtis in the famous 1960
Hollywood movie. “The Great Imposter”, Chiari plays many strikingly
different roles.
_files/image004.jpg)
Tony Curtis as imposter-doctor Fred Demara operating on a wounded Korean
commando
Let’s take a closer look at Chiari in some of its lesser known but important
roles in facial neuralgia, cardiac arrest, respiratory failure,
hypertension, and orthostatic intolerance (fainting upon standing
accompanied with drop in blood pressure). Neuralgia is a term for pain that
occurs along the course of one or more nerves. There are two common facial
neuralgias, trigeminal neuralgia and glossopharyngeal neuralgia. The
cranial nerves involved are the fifth and ninth respectively. Of the two,
trigeminal neuralgia is more frequently encountered. Facial neuralgias are
extremely painful. Patients with these neuralgias find it difficult not to
think about them. As a result, they often obsess about them and commonly
digress into a state of clinical depression. The pain is so severe for some
men with this condition that they are unable to even shave. These
neuralgias are believed to be caused by a blood vessel or tumor compressing
a cranial nerve. Unfortunately, many doctors, including ENTs who usually
diagnose this condition, are not aware that our friendly Ornithorhynchus can
also compress the lower cranial nerves to give rise to facial neuralgias.
Thus, Chiari can sometimes present as a case of facial neuralgia complicated
by clinical depression. Chakraborty et al1, described a
38-year-old female presenting with trigeminal neuralgia along with headache,
numbness, weakness and gait abnormalities in which foramen magnum
decompression resulted in complete resolution
of her
symptoms. However, being the great imposter that Chiari can be, cases have
also been reported in the medical literature in which it has presented
solely as trigeminal neuralgia with no other symptoms both in adults2
by Rosetti et al and in children3 by Ivanez and Moreno.
Similarly, Chiari has been documented to present as glossopharyngeal
neuralgia by Kanpolat et al4 and Aguiar et al5 as well
as others. In my own case, the first diagnosis I received was mild
glossopharyngeal neuralgia. The diagnosis was derived after other problems
were ruled out. I underwent a CT scan to rule out tumors and a barium
swallow to rule out damage to the throat from silent GERD (gastroesophygeal
reflux disease). The ENT told me that he could not think of anything else
other than stress that could be causing my painful swallowing symptoms.
Because the brain stem controls breathing, heart rate and blood pressure and
Chiari can result in compression to the brain stem, Chiari has also cast
itself in the role of cardiac arrest, respiratory failure, and blood
pressure abnormalities. At least four cases of cardiac arrest caused by
Chiari have been reported in the medical literature. A case of a
31-year-old man in Spain who suffered loss of consciousness and cardiac
arrest with ventricular fibrillation (irregular heart beat) upon moving his
head briskly was reported by Alegre et al6 in 1994. A similar
case in a Polish man was reported earlier by Araszkiewicz, Haftek and Zietra7.
Additionally, our platypus troublemaker, not apt to be type-cast in adult
roles, has also appeared in two fatal cases of sudden unprovoked
cardiorespiratory arrest in children as reported by Martinot et al8
in France.
Ornithorhynchus is also an accomplished
swimmer. He has to be in order to have appeared around the world in
documented cases of respiratory failure and insufficiency. Such cases have
occurred not only in the United States9 but in Spain10,11,
Belgium12, Saudi Arabia13, the Republic of China14,
and the United Kingdom15. It is particularly interesting to note
that in the Belgium case which involved a 45-year-old woman, respiratory
failure was the sole manifestation
with no neurological signs present.
Chiari is also well documented to cause
neurogenic arterial hypertension. Turkish investigators reported a case16
in which suboccipital decompression not only provided neurological
improvement but also led to resolution of the hypertension. More
interesting however is a case reported by Tubbs et al17 at the
University of Alabama at Birmingham involving a patient with a history of
idiopathic (unknown causation) hypertension in which Chiari was ultimately
determined to be the cause. Subsequent posterior fossa decompression of the
patient resulted in an absence of pathologically elevated blood pressure and
the patient remained normotensive at a 24-month follow-up evaluation. On
the other hand, Chiari as the cause of hypotension has been more
controversial. In 2001, reports in the media that decompression surgery
provided benefit to patients diagnosed with fibromyalgia/chronic fatigue
syndrome outraged much of the medical community as many believed there was
no basis for the surgery in patients without Chiari malformations.
Proponents of the treatment based their argument on a connection between
Chiari and fibromyalgia/chronic fatigue syndrome. To dispel this
connection, Garland and Robertson18 of the Vanderbilt University
Department of Medicine, reviewed the literature for reports of orthostatic
intolerance (fainting upon standing accompanied by a drop in blood pressure)
in Chiari patients as patients with fibromyalgia/chronic fatigue syndrome
often present with orthostatic intolerance.
The investigators found the connection between Chiari I malformation and
orthostatic intolerance to be almost entirely unsupported. That was in
2001. However, more recently (2005), Prilipko et al19 of the
University of Lausanne in Switzerland reported the first case of a Chiari I
malformation patient with frequent recurring orthostatic intolerance whose
symptoms resolved completely after surgical intervention. How could one
expect anything less from the great imposter, Ornithorhynchus? Such an
irresistible dramatic role simply could not be denied for long.
-- Ray D'Alonzo, Ph.D.
* pronounced:
Or`ni*tho*rhyn"chus
1Minim Invasive Neurosurg. 2003 Feb:46(1):47-9.
2Neurosurgery, 1999 May;44(5):1122-3.
3Rev Neurol. 1999 Mar 1-15;28(5):485-7.
4Neurosurgery, 2001 Jan;48(1):226-8.
5Neurosurg. Rev. 2002 Mar;25(1-2):99-102.
6Int J Cardiol. 1994 Oct;46(3):286-8.
7Neurol Neurochir Pol. 1973 Jan-Feb;7(1):125-8.
8Intensive Care Med. 1993:19(2):73-4.
9Clin Neurol. Neurosurg. 2001 Apr;103(1):43-5.
10Arch Bronconeumol. 1999 Dec;35(11):560-3.
11Eur Respir J. 1995 Apr;8(4):661-3.
12Rev Mal Respir. 1996;13(4):440-2.
13Eur Neurol. 1996;36(1):36-8.
14Chest. 1991 May;99(5):1294-5.
15J Neurol Neurosurg Psychiatry. 1988 May;51(5):714-6.
16J Neurosurg. 2005 Jun;102(6):1147-50.
17J Neurosurg. 2004 Feb;100(2 Suppl Pediatrics):194-6.
18Am J Med. 2001 Nov;111(7):546-52.
19J Neurol Neurosurg Psychiatry. 2005 Jul;76(7):1034-6.
** If you
would like to share your comments, thoughts, or ideas with Ray,
please send them to dalonzo.rp@fuse.net.
Due to the volume and nature of email received, individual responses are not
possible. **
[Ed. Note: The opinions expressed above are solely those of the
author. They do not represent the opinions of the editor, publisher,
or this publication. Mr. D'Alonzo is not a medical doctor and does not
give medical advice. Anyone with a medical problem is strongly
encouraged to seek professional medical care.]
Return To Table Of Contents
|