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WEDNESDAY, Oct. 15 (HealthDayNews) -- Patients with
lupus develop antibodies for the disease up to nine years before
symptoms occur, researchers report.
Lupus, a disorder of the immune system, shows itself
in a variety of ways and produces antibodies that attack the immune
system.
"That self-destructive process is why the disease is called
an autoimmune disease," says Dr. John Harley, the lead researcher
and a professor of medicine at the Oklahoma Sciences Research Center
and the University of Oklahoma Health Sciences Center.
Fifty years ago, lupus had a mortality rate of 50 percent. Now
the mortality rate is less than 10 percent, Harley says. However,
lupus remains a life-threatening and life-altering disease, he adds.
Writing in the Oct. 16 issue of the New England Journal of Medicine,
Harley and his colleagues report for the first time that these antibodies
are present years before lupus becomes symptomatic.
The specific antibodies are antinuclear, anti-double-strand DNA,
anti-Ro, anti-La, anti-Sm, anti-nuclear ribonucleoprotein, and antiphospholipid.
The researchers looked for these antibodies in blood samples from
130 lupus patients. The blood samples were collected years before
symptoms of lupus appeared.
"The typical patient who gets lupus has positive antibodies
in their blood years before the diagnosis," Harley says. Of
the 130 patients, 115 had one or more of these antibodies up to
nine years before symptoms appeared, the investigators report.
"One of the surprising findings was that there appears to
be an order in which antibodies appear. Anti-nuclear ribonucleoprotein
and anti-Sm antibodies appeared just before diagnosis, while other
antibodies, like anti-Ro and anti-La, appear years and years before
diagnosis," Harley notes.
He adds that anti-double-strand DNA antibodies appear about two
years before diagnosis.
Harley believes that his findings indicate that patients who test
positive for any of these antibodies are the ones most likely to
develop lupus.
However, these results should not be taken as a recommendation
to test people for these antibodies, he adds. This is only preliminary
data, he says.
What is needed, according to Harley, is a clinical trial that
would treat people who have these antibodies with Plaquenil, a drug
that inhibits lupus in patients with mild disease, to see if this
treatment would prevent the onset of lupus.
The problem, Harley says, is that not all people with these antibodies
develop lupus.
"There are people with positive tests who go on for years
and years, if not decades and decades, without developing lupus.
Right now, you can't tell which patients are at high risk for lupus
and which are not, based on the test alone," he adds.
The latest findings move researchers closer to having better therapies
for lupus in the future. Right now, though, there is no implication
for treating patients with lupus or those who are at risk for lupus,
Harley says.
Harley's team continues to look into both genetic and environmental
causes of lupus. On the genetic side, they have collected data from
400 families in which at least two members have developed lupus.
So far, they have identified 12 genetic effects to the disease,
and they are now working to identify the specific genes involved.
The researchers have also been doing immunochemical studies of
the interaction of antibodies and antigens. Their findings have
shown that Epstein-Barr virus may play a role in the development
of lupus.
Dr. Robert Shmerling, an associate professor of medicine at Harvard
Medical School (news - web sites) and author of an accompanying
journal editorial, comments that the findings are "interesting
and intriguing."
However, Shmerling is not sure they are useful in treatment right
now. "I don't think we should be screening people, and I doubt
that if we did, that it would lead to an earlier diagnosis of lupus,"
he says.
"Even if the antibodies were absolutely perfect in predicting
lupus, there is no preventive therapy," he adds.
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