New Clues to Endometriosis

By Jane Farrell

Researchers have taken a step toward better diagnosis and treatment of endometriosis by discovering a pattern of molecules and cellular activity linked to the painful condition.

Endometriosis, the invasion of uterine tissue into surrounding organs, including the peritoneal cavity and the ovaries, affects an estimated 10 percent of women. It can cause severe pain and infertility. It’s also difficult to diagnose because symptoms may disappear for years at a time, and very little is known about its cause.

The discovery, by researchers from the Massachussetts Institute of Technology, was published in the journal Science Translational Medicine.

“Endometriosis patients report symptoms of infertility and pain, and beyond that, it’s just kind of a guessing game. There are few molecular mechanisms known,” says the study’s lead author, biological engineer Linda Griffith.

In the new study, the researchers analyzed peritoneal fluid from 77 patients who reported a wide range of symptom severity. For each sample, they measured 50 proteins, including inflammatory compounds known as cytokines. These substances regulate the body’s response to infectious agents but can also cause inflammation during endometriosis.

The investigators found a distinctive profile linked with certain symptoms, including lesions in the ovaries.  This pattern also affected fertility.

Robert Taylor, a professor of obstetrics and gynecology at Wake Forest School of Medicine who was not part of the research team, said that the “signature” of the cytokine would be useful if tests could be developed to detect them in urine or blood samples. Those samples are easier to obtain than peritoneal fluid.