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| An
Evasive Bacteria May Cause Fatigue "Syndromes" |
"Your friends, your colleagues, your boss, your
family all have to take on faith that you have an
illness, and that you are telling them the truth about
the way you feel," says Sophie Wilkinson, who
has suffered with chronic fatigue syndrome for 12
years.
Only in the last six months has a doctor finally
confirmed that Sophie has an illness. A tiny bacteria
called mycoplasma may play a role in such puzzling
conditions
that defy easy diagnosis and treatment, but persist
tenaciously over time. Patients with chronic fatigue
and Gulf War illness, and other chronic disorders
experience exhaustion, muscle and joint pain and
a lack of mental acuity dubbed "brain fog."Resistant
to treatment, the diseases cause some formerly active
people to become bedridden. Others can barely work
or attend school part time.
THREE MAIN SYMPTOMS
"It's not the kind of disease that you would
make up," says Sophie. "You have no life.
There's a whole constellation of symptoms that wax
and wane, depending on the particular episode. The
lack of stamina is a consistent feature."
The elusive array of complaints shared by chronic
illness patients generally comprise a triad of symptoms:
--lack of stamina
--muscle or joint aches
--neurologic problems like poor memory and concentration.
It's not clear how mycoplasma drive these symptoms,
but the tiny bacteria leave clues that researchers
are beginning to decipher. "We can now identify
the DNA of mycoplasma in the blood of some Gulf
War syndrome patients," says Sam Donta, M.D.,
specialist in infectious diseases at Boston University
School of Medicine. "But just finding the DNA
footprint doesn't tell us if that's the cause of
the disease."
Mycoplasma represent the tiniest free-living bacteria.
They can thrive on open surfaces of the body including
the mouth, respiratory system, the genital tract,
and the urinary tract. Unlike viruses that need
to reproduce themselves inside living cells, mycoplasma
can replicate on their own. "They have finger-like
projections that stick out, and researchers have
begun to identify the chemicals that make mycoplasma
sticky," says Donta. "That stickiness
helps them live on the open surfaces of the body."
Mycoplasma proved very difficult to grow in the
laboratory for research
purposes, and remained a mystery for years. "They
were first associated with
an unusual kind of pneumonia," says Donta.
"They're tricky, because if you didn't know
about mycoplasma, you might think a patient had
a viral form of pneumonia. There aren't very good
drugs for the treatment for viral pneumonia, but
antibiotics work against bacterial pneumonia."
Today's antibiotics kill active bacteria, but mycoplasma
grow too slowly, and
antibiotic treatment doesn't wipe them out. "Apparently,
mycoplasma go through very slow periods of growth
with low metabolic activity, kind of like hibernation,"
says Donta. Many antibiotics either interfere with
the metabolism of the bacteria, or destroy their
cell walls. Neither approach, however, works well
against the
ultra-slow-metabolizing mycoplasma, which have no
cell walls.
Donta explains that scientists recently identified
a few more mycoplasma, in
addition to the well-known mycoplasma pneumonii.
Some were renamed, like
ureaplasma, which is associated with the urinary
tract. Ureaplasmas have been
link to small birth weights and miscarriages as
well as genital-urinary diseases.
"There is strong evidence that mycoplasma
species are associated with many
illnesses including chronic fatigue syndrome, rheumatoid
arthritis, and other chronic infectious diseases,"
says Donta. "Researchers discovered that mycoplasma
get into the body's tissues and just sit for a while.
Periodically they become more active and take some
nutrition. Then they go into a resting phase again
with low metabolism. "That's why an antibiotic
doesn't kill them," says Donta. "Antibiotics
either target the cell wall, which mycoplasma lack,
or they block metabolic
pathways used to make new proteins."
LONGER TREATMENT NEEDED
"It could be that slow metabolic activity is
the mycoplasma's staying power," says Donta.
"Like a turtle, it may be slow, but it hangs
on." Researchers think prolonged antibiotic
treatment may improve symptoms for some chronic
sufferers of Gulf War illness. "We set up a
Gulf War illness study to track mycoplasma DNA,"
says Donta. "We're trying to see if the mycoplasma
disappear in patients whose illness improves after
taking the antibiotic doxycyclene. The purpose is
to learn what role, if any, mycoplasma play in the
illness."
In the study, which is being conducted at 30 Veterans
Affairs Medical Centers
around the country, patients take either the antibiotic,
or a placebo for one
year. During six months of follow-up care, doctors
will try to determine if patients taking the antibiotic
improved, and if they stayed better.
"DNA analysis will be done so researchers
can determine if the patients who got better showed
a decrease in mycoplasma DNA," says Donta,
who leads the study.
MULTIPLE SYMPTOM DISORDERS
There's a lot of controversy about chronic disorders
like chronic fatigue
syndrome and Gulf War illness. "Some doctors
think they are psychological,"
says Donta, "But I have long since given up
the "evil humor' theory of
disease. Patients are suffering from these diseases
even when physical exams
don't reveal anything of note." "I spent
thousands of dollars on medical tests," says
Sophie. "And I had doctors tell me that I was
healthy when I was sitting in their office feeling
miserable."
The National Institutes of Health recognize chronic
fatigue syndrome as a serious illness. Still, many
people with the disease fail to receive disability
or insurance benefits because doctors and employers
don't believe they suffer from a debilitating condition.
Research studies in immunology, endocrinology and
other fields keep probing the mysteries of chronic
illnesses in a search for urgently needed therapies.
"Wouldn't it be nice if we could wake up all
of the mycoplasma bacteria, and keep them from slowing
down. And then slam them with an antibiotic,"
says Donta. "We need more research to develop
drugs that work against mycoplasma."
Copyright 2000 The New York Times Syndicate. All
rights reserved.
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