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New Parasite Discovered In Some
CFS Patients |
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New Parasite Discovered In Some
CFS Patients
From Patricia Doyle labgal_5@yahoo.com 2- 15-2000
Hello Jeff,
I thought you might like to see the transcript of a CFS radio show that airs in
New York over WEVD about the discovery of a new parasite found in some CFS
patients.
Patty
CFS Radio Program 1-16-00
Host: Roger G. Mazlen, M.D. Guest Dr. Larry Klapow, PhD
Dr. Mazlen: To kick off the new millennium with a good show
that you'll find of
great interest and great importance, I'm talking today with Dr. Larry Klapow,
a Ph.D. in Invertebrate Biology who's in Burlingame, California near San
Francisco. Good morning Larry, welcome to our show.
Dr. Klapow Good morning, Roger, I'm glad to be here.
Dr. Mazlen Can you tell our audience something about the this
suspected new
parasite that you've found in a percentage of patients with Chronic Fatigue
Syndrome? How'd you find it?
Dr. Klapow Well, Roger, it came about as a result of a
conversation I was
having with an immunologist friend of mine, Dr. Vincent Marinkovich, here in
Redwood City, California. He was treating a CFS patient we thought might have
a roundworm infection. The patient had a low grade eosinophilia and some
unusual rashes on the torso that suggested the possibility of threadworm
disease. Antibody tests and stool tests were negative. I thought about this
for a while and I know that some chronic parasites migrate between the
digestive tract and the respiratory tract and some of them are coughed up in
sputum. So I looked at the sputum and that's where I found it. I called the
new parasite "Cryptostrongylus pulmoni", that's a provisional name and it
means "the hidden lung worm".
Dr. Mazlen That's pretty appropriate in terms of what you say.
Dr. Klapow It definitely is, Roger. It's very difficult to
find. And I hope
other people will start looking for it. In fact, I've put together some
material that I think can help them.
Dr. Mazlen You recently completed a small blinded study in
cooperation with a
small number of CFS doctors including Dr. Anthony Komaroff in Harvard. You're
now doing a larger blinded trial and you're also trying to develop a clinical
test for the parasite. But for these other investigators and clinicians, can
you tell us what does the parasite look like and how can they find it?
Dr. Klapow You can identify the parasite, the female by its
mouth parts and
the male by its very intricate reproductive structure. This parasite is very
small. The female is less than a millimeter long and the male is about a third
that length. So, in addition to being small there's also a lot of
difficulties. The specimens I usually pick up are naturally expelled in sputum
and they're usually very decayed and rare and because of this you need very
specialized imaging techniques to find them. They're not expensive techniques,
they're just specialized. In any case I wanted to help people look for this
parasite and so I put together a website which describes how to find it in
great detail. It also includes anatomical drawings. I can give you the website
address if you like.
Dr. Mazlen Yes, give us the address right now, that'll be
great.
Dr. Klapow OK, I'll give you my own email address and then I
can post the
other rather longer address for people who contact me. My email address is
lak123@gateway.net.
Dr. Mazlen Now, this is really important because this
introduces a whole new
dimension about Chronic Fatigue Syndrome and its possible relationship to
roundworm infestation. Can you tell us so far, at least, as you've been
looking, what percentages of Chronic Fatigue Syndrome patients are turning out
to be positive for this worm?
Dr. Klapow Yes, I find the parasites in about 40% of three-day
sputum samples
from CFS patients. However, I have to tell you that yields are very low. In
fact, they're so low that I think I'm probably missing as many positive
patients as I'm finding. The problem here is that over 80% of the positives I
get are represented by only one identifiable specimen. So just by chance it
looks like I'm missing a fairly high percentage.
Dr. Mazlen So, the prevalence can be a lot higher and this, of
course, stirs
some very great interest in terms of causation and etiology which we'll go
into later. Can you tell us anything about the blinded trials so far?
Dr. Klapow Yes, I did a small blinded trial in cooperation with
a number of
doctors including Dr. Anthony Komaroff at Harvard and here are the results. I
think they're interesting but you judge for yourself. 5 of the 11 patients
were positive while all 6 controls were negative. Now, it's a small trial but
if you were trying to do as well by guessing, say by just tossing a coin,
you'd only do as well as I report here in about 1 in a 100 tests, so it's a
very hard thing to do by just guessing. The results of this small trial can be
used to devise an experimental design for a large trial that could give a
statistically significant result and going through that exercise suggests that
between 50 and 80 samples will be needed. Now, it may take some time to
process these samples microscopically. It's now taking me somewhere between 50
and 100 hours to find a single positive patient so I think the progress will
be slow, that is unless we can get something more rapid going in the form of a
PCR test.
Dr. Mazlen Well, I certainly congratulate you though for the
effort that
you're making because this is totally important to patients for their
prognosis and recovery ultimately. There's a lot more to learn and, of course,
we're going to go into that and you mentioned the PCR test and that you have
some arrangements whereby this can be developed and hopefully you'll get some
funding to help this along soon. If anybody in the audience is interested in
helping in this regard they can reach me at rgm1@aol.com which is my email
address and I'll forward it on to Dr. Klapow. Larry where do you think these
parasites might be coming from?
Dr. Klapow Well, Roger, they have some specialized anatomical
structures that
suggest that they're related to parasites of animals that live in the jungles
of Southeast Asia. In fact, there's been somewhat of a history of hard to
diagnose parasites coming out of that area and being brought back to "Western"
countries after periods of warfare. It happened in the Victorian era when
French soldiers were returning from this area and brought back the chronic
parasite Strongyloides stercoralis to Europe where it was first diagnosed in
1894. It also happened again in World War II. This time British soldiers
became infected while they were imprisoned in Burma returned to England and 30
years later, in 1974 they were diagnosed with chronic parasites they had
gotten while they were in prison. It's kind of a testament to how difficult
some of these parasites are to find and treat. I would like to look at people
who've been to Southeast Asia and I think I plan to do that as soon as I
finish with the large trial I'm doing on CFS patients now.
Dr. Mazlen It's a natural sequitur because you're going to be
having a chance
to look at all of the veterans of the Viet Nam era who either served in Viet
Nam or Cambodia or neighboring areas. Dr. Klapow That will happen, I think, rather quickly if I can
get the PCR test
going.
Dr. Klapow That will happen, I think, rather quickly if I can
get the PCR test
going.
Dr. Mazlen You say it might be coming from this source and
that's a
possibility. How is it contracted? How do you get it then?
Dr. Klapow I'm really not sure. What I can tell you is this.
I've never seen a
fresh transmissible stage of the parasite in any sputum sample I've seen so
far. I've done a couple of hundred samples at this point. So I don't think
there's any evidence right now of casual transmission. But roundworm parasites
are typically acquired by eating contaminated food, but an outbreak of
Cryptostrongylus infection, if it were transmitted in this way, would look
very different then a typical food poisoning incident where people get sick
within a couple of hours after eating.
Dr. Mazlen That's due to the long latency that you mentioned.
Dr. Klapow Cryptostrongylus is very small but it produces a
larvae which is
very large so there's an implication here that it must be reproducing very
slowly and possibly has a very long latency time. Of course, we know that the
outbreak of Chronic Fatigue Syndrome usually take place over several months
and in some cases a couple of years and that I think would be consistent with
the possibility of a food borne infection with a very long latency period.
Dr. Mazlen Well, now we're going to turn to the clinical side.
Most of the
time that doctors are looking for parasitosis, they look to see elevated
eosinophil and serum IgE, or immunoglobulin E, levels in patients. Isn't this
usually the case?
Dr. Klapow Yes, but that's the first question that I get from
doctors when I
tell them that I found what I think is a new species of roundworm parasite.
Where's the elevated IgE? And the answer is elevated IgE is mainly apparent in
acute roundworm infections. With time, the chronic parasites are able to
suppress the IgE response and many of them produce a clinical picture where
the patients either have normal or lower than the normal average level of IgE
and, in fact, that's the picture you see in CFS and in all the studies I've
reviewed, IgE is lower in CFS patients than in healthy control populations.
Dr. Mazlen Here I want to interject that I'm part of the new
study looking
into C.pulmoni in CFS patients and one of the things that prompted me to call
you and talk to you about getting involved is the fact that I had been seeing
low IgE levels, low eosinophile counts in patients that I thought were
inappropriate.
Dr. Klapow In fact, there was a paper that's a few years old in
the Journal of
Chronic Fatigue Syndrome that indicates that if you correlate IgE and
eosinophil levels with the number of symptoms the patients report, the sicker
they are the lower the IgE and eosinophil counts and that's a statistically
significant relationship.
Dr. Mazlen And I see it and it seems to be borne out. Now, what
do you think
is suppressing IgE in this CFS or Chronic Fatigue Syndrome patients? What's
the mechanism?
Dr. Klapow Well, I think the mechanism may involve the cell
marker CD23 which
suppresses IgE. There are a couple of other things that activate CD23, the IgE
suppresser and those are active herpes viruses and some of the TH1 cytokines,
particularly interferon-gamma and the 2'-5'A, the activator of the latent
RNase enzyme. Both herpes viruses and 2'-5'A, as you know, are highly elevated
in CFS patients. In fact, it looks like some roundworms may be using chronic
viruses as cofactors to help perpetuate their own survival.
Dr. Mazlen That certainly rings true from what I've seen
clinically and that
leads us to another question. If a lot of Chronic Fatigue Syndrome patients
have allergies, they should have elevated IgE levels but a lot of them, as we
were just saying, don't. It seems to fit the model you propose of a
suppresser.
Dr. Klapow Yes, there are some doctors, in fact, that think
allergy is a risk
factor for getting a roundworm infection and that's because patients who tend
to produce too much IgE to non-specific stimuli, harmless things, may not have
enough reserves left over to fight off the parasites so they get a foothold,
and in fact, initially, you can even see patients who report increased
allergies, but later on when they're diagnosed with CFS and the presumptive
parasite, if we may go so far and speculate, has suppressed their IgE response
and the values come out clinically low.
Dr. Mazlen Now, this brings us to a leading question, which,
obviously is a
speculation, but that's all right because that's what this show is about. We
want to raise issues and have other people contribute to answering them as
well. There seem to be many infectious agents that have been proposed as being
possible etiological agents for Chronic Fatigue Syndrome. None of them have
held up specifically as a single causative agent. What do you think about this
roundworm infection, c.pulmoni, is it a primary infection or is it just
another opportunistic organism?
Dr. Klapow Well, I don't know if it's a primary cause of CFS.
We'll just have
to have to go through the rules of Koch's postulates and see how far we can
get. I think it's an interesting candidate for a possible primary agent. I
don't think it's an opportunistic infection. Opportunistic infections are
usually airborne and are present everywhere. They're just waiting for our
immune systems to be weakened before they establish a chronic infection.
Cryptostrongylus doesn't seem to be ubiquitous. If I'm right about the
taxonomy, it looks like it's coming out of a particular geographic area.
They're are also a number of things that I think can connect roundworm
infection to the major physiological systems that malfunction in CFS. And they
have to do with the wide variety of physiologically active agents roundworms
are able to secrete.
Dr. Mazlen We're going back now and talking about the hormones
that these
roundworms secrete, namely vasoactive intestinal polypeptide, which is known
as VIP, and hippocampal cholinergic neurostimulatory peptide which is known as
HCNP, and what they do and Larry, what do these hormones cause? What do they
do?
Dr. Klapow Well, VIP is involved in regulating blood pressure
and blood flow.
It's important in regulating blood flow to the brain. It's believed to be
implicated in orthostatic intolerance from which a number of CFS patients
suffer. And, it also controls hypothalmic CRH, a hormone that's ultimately
responsible for the level of cortisol in the blood which is suppressed in CFS
and it's also suppressed in chronic roundworm infections. And the other one,
HCNP, is a limbic system neuropeptide and it's believed to be involved in
memory and immune function. When it goes wrong in areas that have Alzheimer's
lesions, there are cognitive symptoms. In fact, some doctors have suggested
that CFS looks in some respects like a reversible form of Alzheimer's.
Dr. Mazlen It seems like that sometimes.
Dr. Klapow Well, the bad news is that it bares any resemblance
to that
disease. *What good news there is, is that the cognitive symptoms come and go,
without apparently doing permanent damage. I think it is a reasonable hope
that increasingly effective treatments for CFS will be found in time to
substantially help most of those who now suffer from this difficult and often
misunderstood disease.
*Added to transcript by Dr. Klapow after the show.
Transcribed by
Carolyn Viviani carolynv@inx.net
Permission is given to repost, copy and distribute this transcript as long as
my name is not removed from it.
© 2000 Roger G. Mazlen, M.D. |
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