SLE is linked to an abnormal mix of bacteria in the gut. This is according to a new study led by scientists at NYU School of Medicine.
While bacterial imbalances have been tied to many immune-related diseases, including inflammatory bowel disease, arthritis, and some cancers, the authors of the current study say their experiments are the first detailed evidence of a link between bacterial imbalances in the gut and potentially life-threatening forms of SLE.
The new study, publishing in the Annals of Rheumatic Diseasesonline Feb. 19, showed that 61 women diagnosed with SLE had roughly five times more gut bacteria known as Ruminococcus gnavus, than 17 women of similar ages and racial backgrounds who did not have the disease and were healthy. Lupus is more common in women than in men.
Moreover, study results showed that disease "flares," which can range from instances of skin rash and joint pain to severe kidney dysfunction requiring dialysis, closely tracked major increases in R. gnavus bacterial growth in the gut, alongside the presence in blood samples of immune proteins called antibodies, specifically shaped to attach to the bacteria. Study participants with kidney flares had especially high levels of antibodies to R. gnavus.
The discovery may lead to better treatments for lupus, which can damage the skin, joints and organs, study author Dr. Gregg Silverman said.
"Current lupus therapies seek to dampen or destroy the immune system," said Silverman, a professor of medicine and pathology at NYU Langone Health in New York City.
"The idea that we might find in some patients that their disease is being worsened by bacteria in their intestine may mean we [find] much more benign therapeutic approaches," he added. "This is something I'm excited about because I think it really relates to the health and well-being of patients and people."