New Test May Revolutionize Endometriosis Diagnosis

Researchers are developing a new test that would allow diagnosing endometriosis without surgery.

Up to 10% of girls and women of reproductive age are affected by endometriosis, a condition where cells similar to those in the lining of the uterus grow in other parts of the body, particularly on and around the reproductive organs.

Endometriosis is often accompanied by chronic pain and infertility. However, despite causing debilitating symptoms, it usually takes four to 11 years after their onset to receive the diagnosis.

One of the reasons for the diagnostic delay is the dismissal of women's concerns about their pain, according to Dr. Katrina Moss, a research fellow at the University of Queensland. Period pain has been long normalized, which means that some women don't speak up about it.

When they do, many women are told that periods are meant to be painful. It's true that some discomfort can be expected, but if it gets in the way of normal everyday activities such as working, studying, or caring responsibilities, then it's not normal.

Moss

Moreover, the symptoms of endometriosis can be non-specific and can overlap with other conditions, like bladder infection or irritable bowel syndrome, which makes diagnosis harder.

Laparoscopy, a surgical procedure to examine pelvic organs, is the gold standard for endometriosis diagnosis and treatment. Moss says the procedure is expensive, invasive, and requires a long recovery time, which means that some women cannot access it due to high costs as well as work or caring commitments.

A new noninvasive test, which is being developed by Yale University researchers and DotLab, as spotted in a recent patent application, could become a breakthrough in diagnosing endometriosis.

The test promises high sensitivity

The new testing approach is based on microRNA (miRNA) biomarkers. MiRNAs are molecules that mainly exist inside the cell but are also detectable in the blood and play a role in regulating diverse biological processes.

These molecules possess specific characteristics, such as levels of specific miRNAs that may be increased in specific health conditions. They can be easily isolated from samples requiring minimally invasive techniques like blood and saliva, and their levels can be quantified with current diagnostic methods, making them promising biomarker candidates for diagnosing various diseases, including cancer and nervous system disorders.

Early research of DotEndo, the new endometriosis test, has shown promising results. A 2020 study published in the American Journal of Obstetrics & Gynecology examined six miRNAs isolated from the blood of women with suspected benign gynecological conditions who later underwent laparoscopy.

In women with endometriosis, the levels of four miRNAs were significantly increased, while the levels of two were significantly decreased.

The test yielded 96% specificity, the ability of the test to identify an individual without a disease as negative, and 83% sensitivity, the ability to designate an individual with a disease as positive.

The DotLab has begun enrollment into the larger study that will examine the effectiveness of DotEndo using blood and saliva samples. Researchers are looking for about 750 women of reproductive age across the United States who have been referred to an operative procedure for endometriosis diagnosis.

What would it mean to individuals with endometriosis?

Hugh Taylor, M.D., inventor of the test and chief of obstetrics and gynecology at Yale-New Haven Hospital, hopes that it will soon be available to patients.

"There is no noninvasive test currently available in the U.S. Right now, we use clinical diagnosis, but when that is unclear, surgery is the current definitive way to diagnose endometriosis," Taylor tells Healthnews.

Endotest, a salivary endometriosis test developed by French company Ziwig, is already commercially available in several European countries. The test, which is based on the analysis of salivary miRNAs, promises >95% sensitivity, specificity, and diagnostic accuracy in women aged 18 to 43.

The test is prescription-only and saliva collection must be done under the supervision of a healthcare professional, according to the Ziwig website.

In a recent communication published in the Australian and New Zealand Journal Obstetrics & Gynecology, doctors cautioned against using Endotest outside a research setting.

They noted that studies validating the test appear to refer to a single cohort of 200 individuals. As data was drawn from a limited population, questions arise about how applicable the test is to a broad, more diverse population outside of France.

Moss says noninvasive diagnostic tests could potentially revolutionize endometriosis diagnosis, but treatment of the condition might not change.

Moss explains, "It can be affirming and empowering for people to receive a diagnosis, as it validates their health experience and opens up pathways to treatment. However, treatment often needs to be surgical so that endometriosis can be excised and related problems, such as adhesions, can be fixed."

The DotEndo has yet to be approved by the Food and Drug Administration, and it can take months or even years. However, thanks to expanding research on miRNA biomarkers, we may see other noninvasive endometriosis tests in the future.