(HealthDay News) -- People with lupus have certain molecular biomarkers that aren't present in those without the disease, a small, preliminary study has found.
"There are currently no defined biomarkers for lupus," said lead researcher Dr. Nilamadhab Mishra, an assistant professor of rheumatology at the Wake Forest University School of Medicine, in Winston-Salem, N.C.
But, in their new study, Mishra and his colleagues found that people with lupus have changes in their micro-ribonucleic acids (microRNAs) that aren't found in people who don't have lupus. "We found 40 are differently expressed between lupus patients and controls," he said.
"RNA acts like a mold for proteins," to help determine what the form and function of genes' proteins will be, explained Dr. Joan Merrill, medical director of the Lupus Foundation of America.
Mishra presented the findings on Friday at the American College of Rheumatology meeting, in Washington, D.C.
Lupus is a chronic autoimmune disease that can damage the joints, kidneys, heart, lungs, brain, blood and skin, according to the Lupus Foundation of America (LFA). The LFA estimates that about 1.5 million Americans have the disease. It occurs 10 to 15 times more often in women than in men.
The disease can vary greatly in severity from person to person, and even for an individual. Some people with lupus have periods of time when no symptoms are present. Common symptoms include achy joints, frequent fevers, extreme and lasting fatigue, a skin rash and anemia.
There are no definitive diagnostic tests for lupus, and because symptoms can come and go, it often takes months, and possibly years, before a person can be diagnosed, according to LFA.
For the new study, the researchers compared the microRNA from five people with lupus to seven age- and sex-matched people without lupus. The people with lupus were not experiencing symptoms of the disease at the time of the study and were not taking commonly prescribed lupus medications during the study period.
The researchers found 40 microRNAs with a 1.5-fold difference in expression between the people with lupus and the control participants. Six microRNAs had a greater than 3-fold difference in expression.
"We hope we've found a biomarker that can be helpful for diagnosis and to help guide treatment," said Mishra, who added that it might also be possible to develop a new targeted treatment based on this and other research.
Said Merrill: "It looks like lupus patients are making funny RNA even when the disease isn't flaring."
Merrill cautioned that while this "novel research is very good research," it's a preliminary study done on a small group of people, and more work needs to be done.
Mishra said one of the next steps is to see if these microRNA changes are present in other autoimmune diseases, such as type 1 diabetes or rheumatoid arthritis, or if they are exclusive to lupus. He also agreed that the current work needed to be replicated in a larger trial.
"What's important is that there's a lot of research going on right now about the many tiny reactions that occur in lupus. Over the next few decades, we may develop medications that are strategic," said Merrill. "We're working on trying to fix a few small interactions between proteins, rather than wallop the whole immune system."
To learn more about lupus, visit the Lupus Foundation of America.