“I got my period when I was 11 and it’s always been painful: my stomach hurt so much I couldn’t go to college; sometimes the pain made me vomit,” says Delphine, now 42. Attenuated by the pill, the pain returns when the young woman stops it to try to have a child. And it intensifies after her miscarriage in 2009.
The many doctors she consulted then contented themselves with prescribing anti-inflammatories. In 2014, one of them still gave him a laparoscopy which revealed adhesions. Nothing more. And it was not until 2016 that the diagnosis was made: endometriosis. “Finally putting a name to my pain has brought me a lot of relief. And that also legitimized her: I was no longer the sissy who listens to herself too much, who is too lazy to go to work, ”recalls Delphine.
The pain described by Delphine is due to the abnormal presence of the endometrium – the lining of the uterus – elsewhere than in the uterine cavity (in the ovaries, fallopian tubes, bladder, intestines, etc.). During menstruation, the endometrium breaks down, hence menstrual bleeding. But, in women with endometriosis, the misplaced mucosa also bleeds. As the blood cannot be evacuated, it creates hematomas and local inflammation.
Like Delphine, women suffering from endometriosis – 1.5 million in France and up to 190 million worldwide – often suffer long years of diagnostic wandering: between seven and ten years in France. A long journey strewn with multiple examinations, sometimes invasive: ultrasound, MRI, laparoscopy… In this context, the announcement of the development of a test capable of diagnosing the disease from a simple saliva sample arouses huge hopes.
To develop it, the team of Sofiane Bendifallah, gynecologist-obstetrician at the Tenon hospital in Paris, relied on micro-RNAs. “These are small pieces of RNA involved in the regulation of gene expression and which constitute biomarkers of many physiological mechanisms”, explains Sofiane Bendifallah. Thanks to an artificial intelligence algorithm, his team was able, among more than 2,600 microRNAs found in the saliva of his first patients, to discriminate between those which are characteristic of the disease and those which are not. “We identified 109 microRNAs that translate endometriosis-specific signaling pathways,” says Sofiane Bendifallah. The results of this first study were published last year in the Journal of Clinical Medicine.
A few days ago, a second study came to drive the point home. “In order to validate our test, we recruited a new cohort of more than 1,000 patients in 15 different centers. The results for all of these 1,000 patients are not yet available, but those obtained for the first 200 demonstrate that our test is more than 95% sensitive and specific. Obtaining such a precise performance to answer such a complex question is a spectacular step forward,” says Sofiane Bendifallah. Samir Hamamah, head of the reproductive biology department at Montpellier University Hospital, is equally enthusiastic: “This test, which has the immense advantage of being non-invasive, will help improve diagnosis and therefore management. »
Daniel Vaiman, head of the “From Gametes to Birth” research team at the Cochin Institute, is more measured: “The approach is promising but, to validate it definitively, it would have been necessary to carry out a randomized study double-blind, which is not the case here. Nevertheless, the researcher welcomes the idea of using microRNAs as a diagnostic tool. Especially since beyond the diagnosis they could also be used to personalize care. “In the future, we could identify the women who will respond best to treatment, those who are most at risk of recurrence… Genetics has made it possible to revolutionize the management of cancers. The same could be true for endometriosis,” says Sofiane Bendifallah.
In the meantime, the gynecologist hopes to convince “by the end of the year” the French health authorities to authorize the marketing, or even the reimbursement by Social Security, of his test called Ziwig Endotest®. A question that is far from trivial insofar as it still costs several hundred euros.