ENVIRONMENTAL CONNECTION TO LUPUS???

[Guest guest]

Environmental Reason for Lupus?

New Findings Show Environmental Influences Can Aggravate Disease

By Salynn Boyles

Aug. 5, 2002 -- Environmental factors have long been thought to help

trigger lupus in people who are genetically predisposed to get the

disease. Now researchers have identified just such an environmental

trigger in mice, and it may help them understand the causes of lupus

in humans.

The findings provide some of the best direct evidence yet that

environmental influences play a role in the onset and advancement of

lupus, an autoimmune disorder that causes the body's immune system

to attack healthy tissue, resulting in a wide range of symptoms

including kidney disease, arthritis, fatigue, joint pain, and

anemia.

In this study, reported by University of Florida researchers in the

August issue of the journal Arthritis and Rheumatism, mice

predisposed to develop the disease got sick and died much quicker

when they were injected with a component of mineral oil known as

pristane.

Although there is no evidence that pristane causes lupus in humans,

it has been shown to induce inflammatory disease when absorbed

through the respiratory or gastrointestinal tract. Researcher

Westley H. Reeves, MD, says the latest findings may help unravel the

mystery of why some genetically predisposed people get lupus while

others do not.

" We are not saying that mineral oil causes lupus in humans, " Reeves

tells WebMD. " That would be highly speculative. But if we are able

to identify the environmental components in humans that act the way

pristane does in mice, we may be able to reduce the probability that

someone who is prone to lupus will actually get it. " Reeves is chief

of rheumatology at the University of Florida College of Medicine.

In the study, mice genetically engineered to develop lupus were

injected with either pristane or salt water. As anticipated, all of

the predisposed mice developed lupus-specific antibodies, but the

mice injected with pristane developed more antibodies more quickly.

Disease symptoms were also dramatically accelerated in the pristane-

injected mice - 75% died within six months of injection, compared to

just 9% of mice injected with the saline solution.

The findings suggest that environmental factors play a bigger role

in the development of lupus than has generally been believed, says

researcher Hideo Yoshida. Isolating those environmental factors and

either avoiding them or treating for them may turn out to be a

relatively simple way to prevent or manage the autoimmune disorder.

" We know that the genetic components of lupus are pretty

complicated, and there is not much that we can do about them right

now, " Reeves says. " The environmental components, however, are

something that we might be able to change. "

It is not clear how many Americans have lupus. Estimates ranged from

240,000 to 4 million, but the Lupus Foundation of America puts the

figure at 1.4 million. Women are nine times more likely to develop

lupus than men. Autoimmune disease expert Helmick, MD, of

the CDC says a national registry is needed to get a better handle on

just who has lupus and whether more people are getting it than in

the past.

In a study published last May, Helmick and colleagues reported that

women are five times more likely to die of lupus than men, and that

the number of African American women who die from the disease has

increased by 70% over the last two decades.

But Helmick tells WebMD that it is unclear whether more women are

actually dying or whether the increase is due to better diagnosis.

" We need to develop a better understanding about just how many

people have lupus so that we will know what these figures mean, " he

says. " A population registry would help us figure out what is going

on throughout the United States. "

© 2002 WebMD Inc. All rights reserved.

---------------------------------------------------------------------

Our Credentials | Feedback

WebMD Privacy Statement | Read WebMD Terms & Conditions

© 1996-2002 WebMD Inc. All rights reserved.